Exploring the intersectionality of stigma and substance use help-seeking behaviours among lesbian, gay, bisexual, transgender, queer, questioning or otherwise gender or sexuality minority (LGBTQ+) individuals in the United States: A scoping review

ABSTRACT

Problematic substance use (SU) is a significant issue among LGBTQ+ individuals, but rates of treatment/help-seeking in this population remain low. This review aimed to investigate literature about intersectional stigma of SU and LGBTQ+ identity and its impact on SU help-seeking behaviours in the U.S. Eligible studies from eight-database were included if peer-reviewed, in English, from the U.S., published between 2000 and 2022, focused on SU, stigma, SU help-seeking behaviours, among LGBTQ+ adults. Of 458 search results, 50 underwent full-text review, 12 were included in the final sample. Minority Stress Theory emerged as a relevant theoretical framework. Findings revealed that increased SU as a coping strategy was associated with minority stress. Intersectional stigma negatively impacted SU treatment experience among LGBTQ+ individuals, leading to avoidance of help-seeking or poor treatment outcomes. Patterns of SU and impact of stigma among LGBTQ+ individuals differ, wherein bisexual and transgender individuals reported significantly more treatment barriers and unique stressors. LGBTQ+ individuals reported earlier age of SU onset and were more likely to encounter opportunities for SU. This review highlights the impact of intersectional stigma on SU help-seeking behaviour among LGBTQ+ individuals in the U.S. Recommendations are provided for future clinical practice, research, and policy to better support LGBTQ+ individuals.

KEYWORDS:

• Gender/sexuality minority
• intersectionality
• LGBTQ+
• stigma
• substance use

Introduction

Substance misuse and mental health among LGBTQ+ population

Substance use (SU) issues are highly stigmatised and undertreated, especially when compared to other mental and physical problems (Batts et al., 2014; SAMHSA, 2015; Yang et al., 2017). However, there is a substantial treatment gap between individuals that perceive a need for SU treatment and those who receive treatment in a formal treatment setting in the United States (U.S.) (Wang et al., 2007), particularly among lesbian, gay, bisexual, transgender, queer, questioning or otherwise gender or sexuality minority (LGBTQ+) individuals (McCabe et al., 2013; Schuler et al., 2018). The lack of LGBTQ+ individuals seeking treatment for SU in the U.S. suggests a deficit in traditional health care services for this population.

Prior studies have consistently shown that LGBTQ+ individuals have higher rates of risky SU and greater severity of substance use disorders (SUDs) compared to their heterosexual and cisgender counterparts (Allen & Mowbray, 2016; Arterberry et al., 2019; Coulter et al., 2015; Drabble et al., 2013; Operario et al., 2014). Moreover, SU patterns vary significantly among LGBTQ+ individuals (Boyd et al., 2019; McCabe et al., 2019; Schuler et al., 2019) where bisexual women exhibit elevated rates of risky SU compared to heterosexual or lesbian women (Demant et al., 2018; Schuler et al., 2018) and bisexual men and women are associated with greater odds of lifetime use for cannabis, cocaine, inhalants and hallucinogens compared to their same-gendered, heterosexual counterparts (Demant et al., 2018). Additionally, SU disparities were highest among younger lesbian women and older bisexual individuals, when compared to their heterosexual counterparts (Schuler et al., 2019). These data underscore the need for understanding SU treatment utilisation and experiences within the LGBTQ+ population. One possible influence on help-seeking and treatment utilisation could be stigma about SU and one’s gender/sexual identity.

Stigma and discrimination against the LGBTQ+ community

Stigma refers to the devaluation of someone’s identity as less than others through social norms (Corrigan, 1998; Goffman, 1963), which may undermine one’s health through social exclusion, lessen one’s self-efficacy to cope positively, exacerbate existing mental health symptoms (Hatzenbuehler et al., 2013; Hendricks & Testa, 2012; Kuyper & Bos, 2016; Reisner et al., 2015). Stigma may exist individually, interpersonally, and structurally, demonstrated by impacts of stress on individuals (White Hughto et al., 2015).

Individually and interpersonally, stigma against LGBTQ+ individuals may contribute to numerous negative SU and SUD treatment outcomes, including negative stereotyping of oneself, delaying/avoiding initiation of services, early termination of SUD treatment, or treatment approaches aimed towards heterosexual individuals that do not meet their treatment needs (Kelly & Westerhoff, 2010; Kidd et al., 2019; Kulesza et al., 2013; Luoma et al., 2012; Pachankis et al., 2020; Phillips et al., 2020; Reisner et al., 2015; Smith et al., 2016). Structurally, stigma exists multidimensionally across overlapping identities and in treatment for SUDs. Racial and ethnic minorities, LGBTQ+, and individuals who hold multiple minority identities and have historically faced stigma and discrimination may experience additional challenges (e.g. oppression/racism in the LGBTQ+ community, heterosexism within communities of colour) resulting to be targeted simultaneously in sexist, racist, and homo/bi/trans-phobic discrimination (Balsam et al., 2013; Bowleg et al., 2003; Bridges et al., 2003; Chae et al., 2010; Giwa & Greensmith, 2012; Han, 2007; Pauly et al., 2016; Radcliffe & Stevens, 2008). The intersection of being a gender or sexuality minority (GSM) and having SU issues, two highly stigmatised groups, creates compounding barriers for LGBTQ+ individuals to access and successfully complete treatment for SU and SUDs (Benz et al., 2019; Luoma et al., 2012; Smith et al., 2016).

Additionally, discrimination and harassment are major challenges faced by LGBTQ+ community. Such experiences are associated with higher rates of anxiety, depression, stress, and SU as a coping mechanism (Casey et al., 2019; Ngamake et al., 2016; Ortiz-Hernández et al., 2009). For example, prior evidence examined the prevalence of hate crimes and stigma-related experiences among GSM adults in the U.S. and found a significant proportion of LGTBQ+ individuals experienced harassment, discrimination, and violence due to their GSM identity which negatively impacted their mental and physical health (Herek, 2009). These challenges can be amplified for transgender individuals, who may delay or avoid treatment due to discrimination against their gender identity and SU behaviours within healthcare settings and further exacerbate SU to cope with identity-related stressors (Clements-Nolle et al., 2001; Felner et al., 2020; Kattari et al., 2020; Powell et al., 2011; Reisner et al., 2015).

Minority stress theory & resilience

Minority Stress Theory (MST; Meyer, 2003) is a widely used theoretical framework that explains the relationship between identity-based stigma, mental health, and well-being among LGBTQ+ individuals (Lefevor et al., 2019; Tebbe & Moradi, 2016). MST has been instrumental in exploring the unique experiences of stress and adversity faced by LGBTQ+ individuals with regards to health and SUD treatment utilisation (Alessi, 2014; McConnell et al., 2018). Although stigma, discrimination, and other forms of minority stress are major challenges in the LGBTQ+ community, it is important to note that resilience has been identified as an important protective factor against sexual minority stressors, stigma, and discrimination (Kosciw et al., 2015; Lee et al., 2020).

Resilience, a strengths-based framework, examines one’s ability to persist and thrive during significant stressors (Knight et al., 2022; Masten, 2001). Particularly, LGBTQ+ individuals may find sources of resilience and strength to navigate minority stress in taking pride in their identity (e.g. who they are), creating chosen families who offer support/care beyond the traditional family structures, and connecting to others in the LGBTQ+ community for a sense of belonging (Bourguignon et al., 2020; Colpitts & Gahagan, 2016; Lee et al., 2020). While challenges still exist, recognising and building resilience are critical for LGBTQ+ community.

Substance use treatment utilization & help-Seeking behaviors

Literature on SU help-seeking behaviours among LGBTQ+ individuals in the U.S. identified two themes that can impact their well-being: treatment utilisation and treatment experience (Allen & Mowbray, 2016; Clements-Nolle et al., 2001; Felner et al., 2020; McCabe et al., 2013; Reisner et al., 2015). For example, LGBTQ+ individuals who expect discriminatory treatment (anticipated/expected stigma) and unfriendly experience from healthcare professionals (e.g. structural stigma) are more likely to avoid seeking services, which may in turn lead to SU to cope with distress (Ashford et al., 2019; Bradford et al., 2013; Meyer, 2003; Reisner et al., 2015; SAMHSA, 2019; Seelman et al., 2017). Moreover, even if treatment is initiated, individuals who experience discrimination and harassment while in treatment have poorer treatment outcomes, lower odds of initiating services in the future, and less comfort with healthcare providers (Bradford et al., 2013; Seelman et al., 2017; Smalley et al., 2015). The lack of identity-affirming treatment within SU treatment for LGBTQ+ clients highlights the need to examine current treatment experiences, and adapt interventions for LGBTQ+ populations that go beyond only identifying barriers within treatment.

Study aim & significance

It is critical that the SU treatment and research profession address the impact of intersectional stigma on help-seeking behaviours among LGBTQ+ individuals in the U.S. in order to facilitate better intervention efforts in this at-risk population. To avoid perpetuating ignorance and harm towards LGBTQ+ individuals with SUDs and co-occurring disorders, a better understanding of the influences of intersectional stigma on help-seeking behaviours is an important step towards addressing this challenge. However, current research exploring relationships between stigma, treatment experience, and health outcomes among LGBTQ+ people in the U.S. has focused primarily on minority identity rather than considering the intersections of multiple stigmatised identities (e.g. minority status and a person with a SU behaviour).

To contribute to this gap, this scoping review aims to provide a comprehensive understanding of the impact of intersectional stigma on SU treatment utilisation and help-seeking experiences within the LGBTQ+ community in the U.S. treatment or study settings by reviewing and evaluating peer-reviewed English literature published between 2000 and 2022 focused on SU, stigma, SU help-seeking behaviours, among LGBTQ+ adults in the U.S. This review intends to identify research, policy, and practice directions that could improve the health outcomes in this population in the U.S.

Methods

Search strategy and information sources

This scoping review was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) checklist (Tricco et al., 2018) and managed through Covidence systematic review software to ensure accuracy and efficiency. Three search strategies were used: (1) electronic database searching; (2) reference harvesting; and (3) grey literature searching. To identify potentially relevant documents, eight bibliographic databases and Google Scholar were searched. Details regarding used databases and combination of keywords, see Supplementary Table S1. This scoping review does not involve direct interaction with human subjects or the collection of new data. Therefore, it does not require Institutional Review Board review and approval. This scoping review does not have a registered review protocol, which is a requirement for systematic reviews.

Eligibility criteria & study selection

A comprehensive review of these databases was conducted (date of last search: March 10, 2023) to identify up-to-date eligible studies if: (a) published between 2000 and 2022; (b) written in English language; (c) peer-reviewed; (d) focused on SU, stigma, SU help-seeking behaviours, and identify as LGBTQ+ populations; (e) sample of the participants are adults; (f) had a treatment or study setting in the U.S. Using the search strategies listed above, the initial literature search generated from eight databases a total of 458 studies. After removing duplicates (n = 41), 417 were left for title and abstract review. Two independent reviewers (YX, MRW) screened all 417 articles separately, n = 367 articles that did not meet the inclusion criteria were excluded. The title and abstract review produced 50 records deemed relevant and eligible for full-text review, 12 were included in this scoping review after full-text review (inclusion criteria see Table 1).

Table 1. Inclusion criteria.

Published between the period of 2000–2022; Written in English language; Peer-reviewed articles; Had a focus on SU^a, stigma, SU help-seeking behaviours, LGBTQ+^b populations; Had a treatment or study setting in the U.S.^c; Sample of the participants are adults (at least 18 years old).

^a SU: Substance Use.

^b LGBTQ+: lesbian, gay, bisexual, transgender, queer, questioning or otherwise gender or sexuality minority.

^c U.S.: United States of America.

Data extraction/charting and synthesis

Each included study was reviewed to extract descriptive information on demographic information and study participant characteristics (e.g. sample size, age, race, LGBTQ+ identity, SU type, age of onset of SU, SU treatment utilisation), design features (e.g. qualitative or quantitative study design, underlying theories and frameworks, study participant recruitment strategies), definitions and types of stigma, identified protective factors for health, outcome measured using measurements, overall findings on the impacts of intersectional stigma on LGBTQ+ community, and suggested implications for future research, practice, and policy. For each article, details were extracted and recorded into a standard Excel data extraction worksheet that has been previously tested and proven to be reliable in prior scoping reviews. Two reviewers (YX, CMS) independently extracted data into the worksheet and met to discuss and clarify the content included in the worksheet. To synthesise data, all the reviewers conducted an iterative review process of included studies to identify commonalities and discrepancies in the main results, conclusions, and implications that characterise the complex concept of intersectionality of stigma and SU among LGBTQ+ individuals seeking treatment in the U.S. All co-authors examined the data extracted from each article after reviewing all studies to approve the current evidence.

Methodological quality assessment

To improve rigour and reliability of our scoping review findings, we selected a 16-item quality assessment tool, Quality Assessment Tool for Studies with Diverse Designs (QATSDD; Sirriyeh et al., 2012) for quality assessment (more details of QATSDD see Supplementary Material). Our included twelve articles were assessed independently by raters to evaluate their quality and methodological characteristics. Each article was scored on a scale from 0 (Not at all) to 3 (Complete) for each quality characteristic, where higher scores indicated better quality (Sirriyeh et al., 2012). Two raters (YX, MRW) independently reviewed the same full-text and analysed the quality of articles by following the QATSDD steps (Sirriyeh et al., 2012). A third independent rater (CMS) was involved in the quality coding process without any prior exposure to the quality assessment coding process to resolve any major score discrepancies between the two original raters. Group discussion was also used to resolve any discrepancies to improve findings’ validity and inter-rater reliability. Our rated articles’ final scores ranged 23–35 points. Results of quality assessment are presented in Table 2.

Table 2. Summary of articles quality assessment.

Total score^a	Article	Explicit theoretical framework	Statement of aims in main body	Clear description of research setting	Sample size considered for analysis	sample representativeness	description of data collection procedure	rationale for data collection tools	detailed recruitment data	statistical assessment of reliability and validity of measurement tools^c	Fit between RQ^b and method of data collection^c	Fit between RQ and format and content of data collection tool^d	Fit between RQ and analysis methods	Justified analytic method	Assessment of reliability of analytical process^d	user involvement in design	Discussed Strengths and limitations
26	Allen and Mowbray (2016)	1	3	2	0	3	2	2	1	1	3	NA	3	3	NA	0	2
31	Operario et al. (2014)	3	3	3	1	2	3	3	2	2	3	NA	3	2	NA	0	3
26	Reisner et al. (2015)	3	3	1	1	3	1	1	1	2	3	NA	3	2	NA	0	3
30	Kidd et al. (2019)	3	3	3	2	3	2	2	2	2	3	NA	3	2	NA	1	2
31	Benz et al. (2019)	3	3	1	2	1	3	2	3	2	3	NA	3	2	NA	0	3
26	Felner et al. (2020)	3	3	2	0	1	3	1	2	NA	NA	3	3	2	3	1	3
32	Lee et al. (2020)	1	3	2	2	2	3	2	3	1	3	NA	3	3	NA	1	3
26	Matsuzaka (2018)	3	2	2	1	2	2	2	1	NA	NA	3	2	2	2	1	2
28	Penn et al. (2013)	1	3	2	2	2	3	3	2	NA	NA	3	2	2	1	0	2
23	Cochran et al. (2007)	1	2	2	1	2	2	2	1	1	2	NA	3	2	NA	0	2
32	Green (2011)	3	3	3	1	1	3	3	3	2	3	NA	3	1	NA	2	2
24	Lukowski et al. (2016)	2	3	2	1	2	2	1	2	0	2	NA	3	1	NA	0	3

^a Of the 16-item quality criteria, 14 apply to the qualitative studies, and 14 apply to quantitative studies, with 16 items applicable to mixed methods where both qualitative and quantitative have been employed. Scoring standard: 0 = Not at all; 1 = Very slightly; 2 = Moderately; 3 = Complete; NA = not applicable. Each item score is the average score of two rates scores.

^b RQ: Research Question: ^c Quantitative; ^d Qualitative.

Results

Study selection outcome

A total of 12 studies were included: three qualitative studies (Felner et al., 2020; Matsuzaka, 2018; Penn et al., 2013) and nine quantitative studies (Allen & Mowbray, 2016; Benz et al., 2019; Cochran et al., 2007; Green, 2011; Kidd et al., 2019; Lee et al., 2020; Lukowski et al., 2016; Operario et al., 2014; Reisner et al., 2015). A summary of the study selection process is demonstrated in Figure 1.

Figure 1. Preferred reporting items for systematic reviews and meta-analyses extension for scoping reviews (PRISMA-ScR) flow diagram – summary of study selection process.

Age, sexual and gender identities, ethnicity, and other demographic information

All studies were conducted in the U.S. The sample size varied substantially (from 10–169,883). The ages of participants ranged from 18 to 96 (Mean Age is approximately 33). Target groups’ sexual and gender identities also varied between gay (67%), bisexual (67%), lesbian (58%), transgender (58%), queer or non-binary (33%), and GSM (8%). The majority of study participants were White/Caucasian, with small numbers of Hispanic/Latino, Asian/Pacific Islander, Black/African American, and Native American represented in the selected articles. Most study participants had GED/high-school or some college/tech-school education background, never married/being single, and reported an annual household income of more than $30, 000. Four studies mentioned some of their participants had completed sex reassignment/gender-affirming surgery (Kidd et al., 2019; Matsuzaka, 2018; Operario et al., 2014; Reisner et al., 2015). For more details of study participant characteristics, see Table 3.

Table 3. Study participant characteristics.

Article Authors	Sample Size	Age	Sexual & Gender Identity	Ethnicity	Other demographic information	Inclusion & Exclusion Criteria	Substance Type
Allen and Mowbray (2016)	Gay or lesbian N = 182; Bisexual N = 126	Gay or lesbian (n = 182): 18–24: 5.2%; 25–44: 57.5%; 45–64: 33.2%; 65 and over: 4.2%. Bisexual (n = 126): 18–24: 19.9%; 25–44: 46.3%; 45–64: 27.4%; 65 and over: 6.4%.	60.3% Gay or Lesbian; 32.3% bisexual.	Gay or lesbian (n = 182): White non-Hispanic: 73.2%; Hispanic = 10.8%. African American = 6.9%; American Indian/Alaskan Native = 5.7%; Asian/Pacific Islander = 3.5%; Bisexual (n = 126): White non-Hispanic: 76.8%; Hispanic = 7.9%; African American = 12.3%; American Indian/Alaskan Native = 2.0%; Asian/Pacific Islander = 0.9%	Gay or lesbian (n = 182): AUD^a status – alcohol abuse (38.3%); never married (65.9%), annual household income $70,000 or more (36%); drug use disorder (42.2%); generalised anxiety disorder (19.3%); mood disorder (47.1%). Bisexual (n = 126): AUD status – alcohol abuse (37.2%); never married (47.2%), annual household income $35,000-$69,999 (34.9%); drug use disorder (53.9%); generalised anxiety disorder (21.4%); mood disorder (58.9%).	Inclusion: Participants in the National Epidemiologic Survey on Alcohol Related Conditions (NESARC) Wave 1 and 2, must be 18+and live in non-institutionalized setting. Exclusion: Under 18, incarcerated and homeless individuals	alcohol drinking
Operario et al. (2014)	n = 191	Mean age = 37.9, SD^b = 11.65.	transgender women (male-to-female transgender; transgender women individuals assigned a male sex at birth and who identify as female)	racially/ethnically diverse: 21% Asian/Pacific Islander, 22% Black/African American, 21% Hispanic, 16% White (non-Hispanic), and 20%mixed race/other.	24% not completed high school, 61% unemployed, 61% earned <$500 in previous month, 28% unstable housing, 52% had a history of incarceration, 7% had completed sex reassignment surgery, 39% reported HIV-positive status (of which 92% were currently receiving antiretroviral treatment).	Inclusion: 18+, identifying as a transgender woman, living or working in the San Francisco Bay Area, having a male primary partner for >3 months. Exclusion: single, living outside the Bay Area, younger than 18, not identify as a transgender woman, do not have a primary male partner for at least 3 months.	no specific types of substances indicated
Reisner et al. (2015)	N = 2,578 Trans masculine respondents	Age 18–24 (27.19%); 25–44 (63.66%); 45+ (9.15%).	51.5% endorsed a binary gender identity; 48.5% indicated a non-binary gender identification (reported living part-time as one gender, part-time as another gender).	74.34% White (non-Hispanic); 25.66% POC^c; Black-3.83%; American Indian/Alaskan Native-3.62%; Hispanic/Latino-4.67%; Mixed Race-10.24%.	Income: low - 30.48%; middle – 34.76%; high – 34.76%. Education: 36.39% – some college or associate's degree; 32.44% – college degree. Health insurance: private – 70.22%; 49% were taking cross-sex hormones and one third (36%) had some form of gender affirmation surgery.	Inclusion: Participants were 18+, voluntarily agreed to complete the survey, and identified as transgender, cross-dressers, genderqueer, and gender nonconforming. Exclusion: Participants who did not agree to complete the survey and/or identify as cisgender.	no specific types of substances indicated
Kidd et al. (2019)	n = 286	non-risky drinkers (n = 180): Mean age = 35.9 (SD = 14.3); risky drinkers (n = 106): Mean Age = 32.3 (SD = 11.2)	transgender identified.	non-risky drinkers (n = 180): 43.9% white; 23.9% Hispanic; 12.2 African American; 20% other. Risky drinker (n = 106): 48.1% white; 14.2% Hispanic; 15.1% African American; 22.6% Other.	non-risky drinkers (n = 180): education attainment- some college or more (81.1%); Annual household income ≤2 × 2016 US^d DHHS^e poverty guideline (42.2%); In a relationship (56.1%); Time since changing gender role/expression (years) > 5 (55%); lifetime gender-affirming surgery (58.3%). Risky drinker (n = 106): education attainment- some college or more (84.9%); Annual household income ≤2 × 2016 US DHHS poverty guideline (45.3%); In a relationship (52.8%); Time since changing gender role/expression (years) > 5 (44.3%); lifetime gender-affirming surgery (48.1%).	Inclusion: Must be 16+, transgender-identifying, and fluent in English or Spanish. Exclusion: Under 16, participants who were cognitively impaired, unwilling/unable to provide contact information, or individuals who plan to leave the study area with 3 years.	Alcohol drinking
Benz et al. (2019)	n = 171 with history of SU^f recruited on a national scale; n = 67 identify as GSM.^g	Full sample (n = 171): Mean age = 22.84(SD = 1.30) GSM sample (n = 67): Mean age = 22.85(SD = 1.23) non-GSM (n = 104): Mean age = 22.84(SD = 1.35)	GSM sample (n = 67): lesbian/gay/queer (32.8%); bisexual (64.2%); something else not captured here (3.0%)	GSM sample (n = 67): 7.5% Hispanic/Latino; 62.7% White/Caucasian; 9% Black/African American; 11.9% Asian or pacific islander; 9% biracial or multiracial	GSM sample (n = 67): single (67.2%); income 30k–69k (47.8%); employed full or part time (74.6%); some college of bachelor’s degree (86.6%);	Inclusion: Being 18–24 years old, being a current U.S. resident, and endorsing current problems with SU. Exclusion: Participants outside of this age range, not a U.S. resident, and no endorsement of SU problems	no specific types of substances indicated
Felner et al. (2020)	n = 59	Mean age = 28 (SD = 3); Ages 21–28 (48%); 29–34 (53%).	lesbian or gay (58%), bisexual (36%), queer (7%). - Cisgender male (39%), Cisgender female (49%), transgender or other gender minority(12%).	non-Hispanic White: 78% (n = 46); Other: 12% (n = 7); Missing 10% (n = 6).	received SUD^h treatment – Yes (59%). (Other demographic information was not reported)	Inclusion: Participants were included in a larger longitudinal cohort study (the Growing Up Today Study) who met criteria for a probable SUD or reported a history of SU treatment, and identified as LGBTQ+^i	no specific types of substances indicated
Lee et al. (2020)	n = 453	Mean age  = 35.6 (SD = 14.0). [unweighted]	Lesbian or gay 59.8% (n = 273), Bisexual 38.9% (n = 176), Not specified 0.9% (n = 4).	White 67.5%, Black or African American 20.8%, American Indian or Alaska Native 1.3%, Asian 2.0%, Pacific Islander 0.2%, Other or unknown 8.2%.	Education-Bachelor’s degree 26.7%; never married 40.6%, US census region-south 51%, current cigarette smoking-nonsmoker 71.5%.	Inclusion: Must be 18+, national sample of English- or Spanish-speaking residents, can be reached by cell phone numbers to complete tobacco survey.	tobacco
Matsuzaka (2018)	n = 11 TGNC^j adults in AA.^k	28–66 (Mean age: 41.8)	3 transmale, 3 transfemale, 5 gender nonconforming.	9 of 11 identified as Caucasian/White; 2 identified as multiracial (i.e. Caucasian, Hispanic, African).	sex assigned at birth: 3 males; 8 females. (Other demographic information was not reported)	Inclusion: 18+, transgender or gender non-conforming identifying, reported a history of SU problems, were currently or formerly active members in AA, and had >90 days of sobriety. Exclusion: using substances, no involvement in AA, <18 years old, cisgender identifying.	alcohol
Penn et al. (2013)	n = 10	Age 22–51.	lesbian: 2, Gay: 3, Bisexual: 2, Transgendered: 1, Lesbian/bisexual: 1, gay/bisexual: 1.	White: 5, Hispanic: 2, Native American: 2, Black: 1.	n = 10 focus group on LGBTQ+ individuals with co-occurring SU and MH.^l (Other demographic information was not reported)	Inclusion: Participants identified as experiencing co-occurring mental health disorders & SUDs and enrolled in a therapeutic programme. Exclusion: Individuals not currently in therapy, with only SUDS or mental health concerns.	no specific types of substances indicated
Cochran et al. (2007)	Total sample n = 4,488. Men who identify as Gay/bisexual (n = 84); woman who identify as Lesbian/bisexual (n = 161).	Gay/bisexual (n = 84): 58.5% aged 18–34, 30.4% 35–49; 11.1% 50+; Lesbian/bisexual (n = 161): 51.3% aged 18–34, 29.3% 35–49; 19.4% 50+.	Lesbian, Gay, and Bisexual Adults	Gay/bisexual (n = 84): Latino = 57.5%, Asian American = 42.5%. Lesbian/bisexual (n = 161): Latino = 68%; Asian American = 32%.	Approximately 4.8% of total sample of people interviewed identified as lesbian, gay, bisexual, and/or reported recent same-gender sexual experiences. Majority of the LGB sample was 18–34 yrs old, some college, identify as Latino, married/cohabiting, interviewed in English, and reported a family income of $75,000 or more.	Inclusion: ages 18+, were administered an extensive face-to-face interview in one of five languages (English, Spanish, Tagalog, Vietnamese, or Chinese). Exclusion: Under 18, unable to speak one of five languages.	no specific types of substances indicated
Green (2011)	N = 218	Mean age = 30.61, SD = 11.91	14 (22%) men identified as gay, and 2 (3%) men identified as bisexual; 108 (70% of women) women identified as heterosexual, 34 (22%) women identified as lesbian, and 12 (8%) women identified as bisexual.	ethnically diverse: 76% White only, 10% Asian/Pacific Islander, 6% Hispanic/Latino, 3% African American/Black, 3% Other, 1% Native American, 1% missing data	employed (5% unemployed); 84% college educated; 70% in committed relationship, 25% reported they had children living in their home; 43% lived in urban area, 41% reported suburban living, and 15% reported country/rural living environments	Inclusion: Must be 18+ Exclusion: Under 18	Alcohol drinking
Lukowski et al. (2016)	Total Sample of all callers: N = 169,883. LGBT group: n = 8,012.	Ranging in age at intake from 18 to 96 years old (mean age = 45.9; SD = 14.0). LGBT group (n = 8012): Young adulthood (18–30): 34.1%; Adulthood (31–45): 34.7%; Middle adulthood (46–60): 25% Older adulthood (> = 61): 6.1%	LGBT (n = 8012): 62.4% identify as female; 37.6% identify as male	Approximately three-quarters of the Quitline callers self-identify as White/Caucasian (70.4% of the LGBT group), the second largest racial group is Black/African American (15.4% of the LGBT group). Nearly 8% of callers identify as ethnically Hispanic or Latino (9.8% of the LGBT group).	Data collected from callers within 14 states (Alabama, Colorado, Idaho, Kentucky, Michigan, Minnesota, Montana, Nevada, North Dakota, Ohio, Pennsylvania, Utah, Vermont, Wyoming). LGBT group (n = 8012): Education: 33.4% – GED/high-school diploma; 32.4% some college/tech school; Marital status: single (never married) – 69.4%; Living with tobacco user – yes- 48.4%; Children at home – 30.2%	Inclusion: Must have used National Jewish Health (NJH) quitline service between Jan 1, 2012 - Dec 31, 2014 Exclusion: If participants enrolled in quitline service more than once between 2012 and 2014, only their first enrolment was used	smoking (cigarettes, smokeless tobacco, e-cigarettes, other tobacco).

^a AUD: Alcohol Use Disorder.

^b SD: Standard Deviation.

^c POC: People of Color.

^d U.S.: United States of America.

^e DHHS: United States Department of Health and Human Services.

^f SU: Substance Use.

^g GSM: gender or sexuality minority.

^h SUD: Substance Use Disorder.

ⁱ LGBTQ+: lesbian, gay, bisexual, transgender, queer, questioning or otherwise gender or sexuality minority.

^j TGNC: transgender and gender nonconforming.

^k AA: Alcoholics Anonymous.

^l MH: Mental Health.

Study participant recruitment

A combination of community outreach strategies was employed in included studies to recruit participants, including advertisements/flyers on LGBTQ+ related websites/listservs/social media and community organisations, participant referral, purposive venue-based outreach, healthcare clinics, cooperated with key informants within existing projects and centres, and using data from national surveys. More information of study participant recruitment strategies, see supplemental document.

Underlying theories and frameworks mentioned in the articles

Eight included articles discussed MST (Meyer, 2003) as their theoretical framework (Benz et al., 2019; Cochran et al., 2007; Felner et al., 2020; Kidd et al., 2019; Lee et al., 2020; Matsuzaka, 2018; Operario et al., 2014; Reisner et al., 2015) and four articles did not report theories as part of their study design (Allen & Mowbray, 2016; Green, 2011; Lukowski et al., 2016; Penn et al., 2013). Another four theories and frameworks were also mentioned in the included articles, including the intersectionality framework (Benz et al., 2019; Else-Quest & Hyde, 2016a, 2016b), the syndemic framework (Operario et al., 2014; Singer & Clair, 2003), the grounded theory (Corbin & Strauss, 2008; Matsuzaka, 2018), and the health equity promotion model (Fredriksen-Goldsen et al., 2014; Lee et al., 2020). Descriptions of these theories, see Supplementary Table S2.

Study research measures

Demographics, identities, self-reported SU-related outcomes, psychological conditions, treatment history/barriers, community participation, and intention for help-seeking were explored via measures in studies. Details of study research measures, see Supplementary Material.

Substance use type and age of onset of substance use

Half of the studies (n = 6) used the general term ‘alcohol and drug use’ or ‘substance use’ not otherwise specified, and the remaining studies focused on alcohol use (33%) (Allen & Mowbray, 2016; Green, 2011; Kidd et al., 2019; Matsuzaka, 2018) and tobacco smoking (17%) (Lee et al., 2020; Lukowski et al., 2016). There were only two articles out of twelve examined the age of onset of SU (Felner et al., 2020; Lukowski et al., 2016), finding that over half of participants (62.8%, n = 4,795) reported they began smoking between ages 13 and 18 years, nearly one fifth (18.4%, n = 1,406) reported onset of smoking <13 years, 16.9% (n = 1,289) reported onset between 19 and 30 years, and only 1.9% (n = 148) reported onset between 31 and 55 years. There was a slightly but statistically significant earlier age of smoking onset in the LGBTQ group (mean = 16.1 years) than the heterosexual group (mean = 16.7 years) (t = 9.53, p < .001) (Lukowski et al., 2016).

Substance use treatment utilization

All of the articles explored past SU help-seeking behaviours or treatment experiences, whereas seven articles examined professional SU treatment utilisation (Allen & Mowbray, 2016; Benz et al., 2019; Felner et al., 2020; Green, 2011; Kidd et al., 2019; Lukowski et al., 2016; Penn et al., 2013). Due to the limited space, details of SU treatment utilisation were presented in Supplementary Material.

Definitions of stigma

Among these included articles, stigma was primarily described as a negative attitude or disapproval attached to characteristics of an individual, and was closely related to unfair discrimination, prejudice, and exclusion. Only two studies (Benz et al., 2019; Matsuzaka, 2018) contained a specific definition of stigma in their articles. In these two studies, stigma was referred to as an attribute that is deeply discrediting a usual person to a discounted and marginalised one (Benz et al., 2019; Goffman, 1963); it could also be understood as a social process/dynamic within social-cultural, economic, and political context to limit resources, opportunities, and well-being of people by labelling a specific group (Link & Phelan, 2001; Matsuzaka, 2018; Poteat et al., 2013).

Types of stigma

In most of the articles, stigma was generally summarised as GSM identity-related stigma, such as anti-gay stigma (Cochran et al., 2007), transgender-related stigma (Operario et al., 2014), or SU-related stigma (Penn et al., 2013) without further discussing its various forms. In five of the reviewed studies (Benz et al., 2019; Felner et al., 2020; Kidd et al., 2019; Matsuzaka, 2018; Reisner et al., 2015), multi-level stigma was explored by discussing its subtypes (e.g. enacted stigma, anticipated/expected stigma, internalised stigma, interpersonal stigma, structural stigma) and examined using standardised measures or questions. Details of subtypes of stigma and stigma measures, see Table 4.

Table 4. Subtypes of stigma.

Article Authors	Subtypes of Stigma	Stigma Measures Used
Reisner et al. (2015)	Enacted stigma (e.g. whether or not had been refused healthcare by a provider due to gender identity) Anticipated stigma (e.g. delayed medical care due to fear of discrimination against their gender identity).	Enacted stigma was operationalised by answering (Yes/No) to the definition. Anticipated stigma was categorised by answering (Yes/No) to the definition.
Kidd et al. (2019)	Enacted stigma (refers to the actual discrimination experiences) Felt stigma (refers to the expectations/anticipations of being stereotyped or discriminated against due to their minority identity or SU behaviours)	Enacted stigma was measured by a 10-item revised Everyday Discrimination Scale (Williams et al., 1997), asking participants to rate how often they had experienced various types of discrimination. Felt stigma was measured by a 10-item revised Stigma Consciousness Questionnaire (Pinel, 1999).
Benz et al. (2019)	Stigma towards GSM identity (GSM^a stigma) Stigma towards SU (SU^b stigma) ○ enacted stigma (direct acts of discrimination and rejection by members of the larger society) ○ anticipated stigma (a belief that prejudice and stereotyping will happen in future interactions) ○ internalised stigma (a process where people identify with a stigmatised group adopt societal stereotypes and apply them to themselves)	The GSM stigma was measured by Everyday Discrimination Scale Experiences of SU stigma was measured by the 18-item Substance Use Stigma Mechanisms Scale (SU-SMS) (Smith et al., 2016) *The 18-item Substance Use Stigma Mechanisms Scale included three 6-item sub-scales: enacted stigma (e.g. ‘family members have thought I cannot be trusted’), anticipated stigma (e.g. ‘healthcare workers will give me poor care’), and internalised stigma (e.g. ‘I feel ashamed of having used alcohol and/or drugs’) (Smith et al., 2016).
Felner et al. (2020)	Proximal-level stigma (self-stigma, anticipated stigma) Distal-level stigma (structural discriminatory laws and policies, e.g. government policy ‘Don’t ask, don’t tell’).	Themes emerged based on qualitative study interviews on questions exploring LGBTQ+^c stressors.
Matsuzaka (2018)	Interpersonal stigma (refers to microaggression experiences within AA^d meetings or socialisation settings) Structural stigma (mainly based on the programmatic components, such as the AA text featuring the dominant perspectives of Caucasian, heterosexual, cisgender men)	Themes emerged based on qualitative study interviews on questions exploring experiences with gender-minority-based stigma in AA.

^a GSM: gender or sexuality minority.

^b SU: Substance Use.

^c LGBTQ+: lesbian, gay, bisexual, transgender, queer, questioning or otherwise gender or sexuality minority.

^d AA: Alcoholics Anonymous.

Protective factors for health

Half of the studies (n = 6) explored and discussed potential protective factors for health (Cochran et al., 2007; Felner et al., 2020; Kidd et al., 2019; Lee et al., 2020; Matsuzaka, 2018; Reisner et al., 2015), including being White/Non-Hispanic, being in the high-income bracket, having a college degree, having private insurance, having undergone surgical gender affirmation or joining affirming programmes (e.g. Gay-Straight Alliances), having had identity integration/sexual-orientation disclosure to friends/family members, and utilising universal resilience (e.g. advertising skepticism and having people to talk about being a GSM) could be potential protective factors for health.

Summary of findings

Overall, the study findings revealed that SU treatment barriers are more common for LGBTQ+ individuals in the U.S. due to the intersections of minority identities-related stigma (e.g. GSM, drug use minority behaviour, ethnicity minority). However, findings from Green’s (2011) and Cochran et al.’s (2007) studies suggested that GSM individuals did not endorse higher levels of SU severity compared to heterosexual individuals, which was inconsistent with other research findings (e.g. Allen & Mowbray, 2016; Benz et al., 2019). Moreover, bisexual, transgender, and gender nonconforming (TGNC) individuals among LGBTQ+ populations reported significantly more treatment barriers and unique stressors (e.g. patterns of SU, sexual risk behaviours, stigma associated with coming out) (Finlayson et al., 2011; Flentje et al., 2015; Lee, 2015; Reback et al., 2014), and lower odds of improvement in treatment outcome than heterosexual and gay/lesbian individuals (Allen & Mowbray, 2016; Felner et al., 2020; Kidd et al., 2019; Reisner et al., 2015).

Secondly, stigma related to SU and having been refused treatment in the past due to GSM identity (enacted stigma) were significantly associated with avoidance of help-seeking for healthcare and delayed or declined medical care when sick/injured or routine prevention care (anticipated stigma) compared to heterosexual individuals (Benz et al., 2019; Reisner et al., 2015). Higher levels of enacted SU stigma predicted a higher likelihood of having sought help in the past while a higher level of felt/internalised stigma was associated with a higher likelihood of improvement (Benz et al., 2019). These findings were consistent with existing research (e.g. Hatzenbuehler, 2009) which highlights the negative impact of stigma on stress and help-seeking behaviours among LGBTQ+ individuals, while inconsistent with some studies who found LGB individuals were more likely to utilise service for SU problems (Allen & Mowbray, 2016).

Thirdly, increased SU has been used as a coping strategy due to gender and sexuality minority stress (e.g. fear of being discriminated against during treatment; worried about being an outsider of the community; to suppress awareness, cognition and feelings related to gender identity) (Felner et al., 2020; Matsuzaka, 2018; Operario et al., 2014; Reisner et al., 2015). A greater level of enacted stigma by providers was associated with a higher level of self-reported SU to cope, and delays in both needed and preventive care (anticipated stigma) was highly related to increased SU which attenuated the effect of enacted stigma (Reisner et al., 2015). Additionally, sociocultural influences (e.g. gathering in gay bars) may increase the availability of SU to cope with interpersonal stressors (e.g. ‘being an outsider’) (Felner et al., 2020).

Moreover, when it related to mental health, GSM individuals reported higher rates of mental health issues (e.g. anxiety, depression, isolation/loneliness, low self-esteem, suicidal thoughts and attempts) compared to their heterosexual counterparts (Cochran et al., 2007; Lukowski et al., 2016; Penn et al., 2013), which further negatively impact their ability to successfully change substance misuse (Lukowski et al., 2016). More specifically, gay or bisexual men were more likely than heterosexual men to report a recent suicide attempt, and lesbian or bisexual women were more likely than heterosexual women to show evidence of depressive disorders (Cochran et al., 2007).

Furthermore, study findings highlighted that increased enacted stigma on GSM identity (e.g. others’ homophobic and transphobic comments/attitudes, being sexually assaulted and/or socially isolated in the treatment facility) was directly associated with lower improved treatment outcome, greater risk for overlapping health challenges, or early termination of SUD treatment (Kidd et al., 2019; Matsuzaka, 2018; Operario et al., 2014). In contrast, those who shared positive and holistic treatment experiences and who remained in the treatment programme, reported feeling respected and accepted by facility staff and other clients (Penn et al., 2013). These positive experiences helped participants integrate their identity into their treatment goals, leading to more beneficial and effective treatment experiences (Penn et al., 2013).

Lastly, LGBTQ+ individuals reported an earlier age of onset of using substances, suggesting they may be more vulnerable to developing SUDs at a younger age than heterosexual individuals (Lukowski et al., 2016). Additionally, study findings showed that LGBTQ+ individuals were more likely to report living with or hanging out with another substance user and being surrounded by SU-oriented occasions (e.g. drag show, pride parade) than heterosexual individuals, which may increase their risk of exposure to SU environments and hinder their ability to maintain sobriety (Lee et al., 2020; Lukowski et al., 2016). A summary of clinical findings, see Table 5.

Table 5. Summary of clinical findings of the scoping review.

LGBTQ+^a individuals experience more substance use treatment barriers due to the intersection of minority identities-related stigma (e.g. gender and sexuality minority, drug use minority behaviour, ethnicity minority). Gender and sexuality minority individuals reported higher levels of substance use severity and higher rates of SUDs^b compared to heterosexual individuals. Bisexual individuals and TGNC^c individuals among LGBTQ+ populations reported significantly more treatment barriers and unique stressors (e.g. patterns of substance use, sexual risk behaviours, stigma associated with coming out), and lower odds of improvement in treatment outcome than heterosexual and gay/lesbian individuals. Stigma related to substance use and having been refused for treatment in the past due to gender and sexual minority identity were significantly associated with avoidance of help-seeking for healthcare and delayed or declined medical care when sick/injured or routine prevention care among LGBTQ+individuals compared to heterosexual individuals. Higher levels of enacted substance use stigma predicted a higher likelihood of having sought help in the past while a higher level of felt/internalised stigma was associated with a higher likelihood of improvement. Increased enacted stigma on gender and sexual minority identity was directly associated with lower improved treatment outcome, greater risk for syndemic/overlapping health challenges, or early termination of SUD treatment. Increased substance use has been used as a coping strategy due to gender and sexuality minority stress (e.g. others’ homophobic and transphobic comments/attitudes, being sexually assaulted and/or socially isolated in the treatment facility). Gender/sexual minority individuals reported higher rates of mental health issues (e.g. anxiety, depression, isolation/loneliness, low-self-esteem, suicidal thoughts and attempts) compared to their heterosexual counterparts, which further negatively impacted their ability to successfully quit substance use. gay or bisexual men were more likely than heterosexual men to report a recent suicide attempt, and lesbian or bisexual women were more likely than heterosexual women to show evidence of depressive disorders There are significant differences in substance use patterns between LGBTQ+ individuals and heterosexual individuals in which LGBTQ+ individuals reported an earlier age of onset of using substances and being surrounded by substance use-oriented occasions (e.g. drag show, pride parade) than heterosexual individuals

^a LGBTQ+: lesbian, gay, bisexual, transgender, queer, questioning or otherwise gender or sexuality minority.

^b SUD: Substance Use Disorder.

^c TGNC: transgender and gender nonconforming.

Discussion

This scoping review discovered discrepancies and inconsistencies in research findings between studies regarding the impact of stigma on SU help-seeking behaviours among LGBTQ+ individuals in the U.S. While most studies suggested that LGBTQ+ individuals reported higher levels of SU and higher severity rates on SUDs than heterosexual individuals, some studies found GSM individuals do not have higher levels of SU severity compared to heterosexual individuals. Moreover, enacted stigma and anticipated stigma were found to be significantly associated with avoidance of help-seeking and delayed or declined medical care in most studies, while some studies indicated that LGB individuals were more likely to utilise SU treatment services. These discrepancies in findings may be attributed to various reasons, such as the differences in sampling strategies, the different layers and diverse intersectional minority identities, the difference of research settings, or the various of measures that used to assess SU severity and consequences in the studies (e.g. use well-established measures or DSM diagnostic criteria VS. study teams’ self-developed questions). Furthermore, our review suggested bisexual and TGNC individuals reported significantly more treatment barriers and unique stressors and lower odds of improvement in treatment outcome than heterosexual and gay/lesbian individuals (Allen & Mowbray, 2016), which may have contributed to these discrepancies. However, the discrepancy on utilisation of SU services among LGBTQ+ individuals also suggested the observed impact of stigma on help-seeking behaviours may not be universal across all GSM groups and/or all treatment or healthcare sectors (e.g. inpatient, outpatient, community-based healthcare), indicating an important research area for future study.

In conclusion, these discrepancies and inconsistencies in research findings underscored the need for additional study to better understand the complex intersections of GSM identities, SU patterns, and treatment barriers experienced by LGBTQ+ individuals in the U.S. These findings also highlighted the significance of providing culturally competent and affirming care that could address the unique challenges and stigma faced by LGBTQ+ individuals in the U.S.

Diversity & inclusion in substance use among LGBTQ+ studies

This review examined demographic characteristics of participants in the included studies, with substantially varied sample size ranging from 10 to 169,883. The findings suggested the review’s sample populations were diverse in terms of age, sexual and gender identities, ethnicity, and other demographic information (e.g. education, household income, relationship).

However, all the studies have a treatment or study setting in the U.S., and the data seems skewed towards those being White/Caucasian, single/never married, had GED or college education background, and with a middle-to-high income level, which may limit the generalizability of the overall findings of the review to a more diverse and global population both within the U.S. and in other countries. Therefore, it is critical that future research recruit more representative samples from varying countries, educational backgrounds, income levels, and relationship situations to ensure the relevance of these findings across a wider range of individuals and contexts. Additionally, future research should consider including more racial and ethnic minorities (e.g. Black, Indigenous, and People of Color (BIPOC) individuals) and people who have disabilities in their study to improve the diversity and generalizability of the findings to those with intersectional identities. Indeed, the various demographic characteristics of sample populations may play a role in the findings, which should be taken into account when interpreting and generalising the findings to other populations to avoid potential biases.

Implications for clinical practice

This scoping review recommended that professionals should engage in continued education/training to remain informed of current research findings and LGBTQ+ rights-related policies to better provide psychoeducation to LGBTQ+ clients, particularly TGNC clients, regarding the risks and benefits of participating in peer support groups (e.g. Alcoholics Anonymous) for recovery and gender transitions. Moreover, professionals should acknowledge the potential risks, microaggressions, harassment, and biases/prejudices against LGBTQ+ communities within treatment settings and take a more open stance in implementing appropriate solutions for a better treatment setting and an LGBTQ+ affirming space (e.g. gender-neutral restrooms).

Additionally, because LGBTQ+ youth initiate SU at a younger age than their heterosexual counterparts, professionals who work with young adults or youth in particular should give special consideration on exploring the process of ‘coming out’ both outside and within the therapeutic context and in relation to their SU behaviours. Healthcare professionals should also inquire about individuals’ barriers to receive treatment and past treatment experiences once in treatment (e.g. gender dysphoria) to gain a better understanding of the treatment process and client’s desired treatment outcomes.

Notably, the findings suggested that healthcare professionals should utilise diagnostic interviewing or motivational interviewing techniques and integrate two key themes from the research into their daily practice with the LGBTQ+ population: the pink elephant in the room (‘the role of sexual identity in therapy’), and searching for an authentic and holistic approach in treatment for clients to freely discuss their minority identities and how it intersects with their mental health, SU, or other issues to understand their unique experiences and tailor the treatment plans to meet their specific needs.

Furthermore, the continuity of care between primary health care providers and therapists in supporting LGBTQ+individuals’ mental health and physical well-being, was also a notable finding from this review. Healthcare professionals should also consider the role of Adverse Childhood Experiences (ACEs) and exposure to SU-oriented social environments in the treatment, which may be beneficial to understand these GSM individual’s relationship with substances, mental health disorders, and psychosocial distress (e.g. discrimination and harassment). Lastly, findings revealed that discussing current social support networks and the role of SU in social interactions is crucial for a better treatment outcome.

Overall, these implications on clinical practice emphasised the importance of providing individualised, inclusive, culturally humble (e.g. tailed treatment plants for BIPOC communities), and LGBTQ+ affirming care for GSM individuals seeking SU treatment to optimise treatment outcomes. A summary of implications for clinical practice, see Table 6.

Table 6. Implications for clinical practice, research, and policy.

Article Authors	Clinical Practice Implications	Research and Policy Implications
Allen and Mowbray (2016)	When working with clients, clinicians should be aware of biases towards a heterosexual orientation. Taking a more open stance, this will lead to improved communication, correct framing of social relationships, and correct clinical judgments for treatment planning.	Researched focused on specialised communities is pertinent to understand specific barriers associated with gender and sexual minorities and treatment utilisation for alcohol related problems. This research may identify specific barriers for particular GSM^a subgroups (i.e. bisexual individuals) with alcohol related problems and co-occurring disorders.
Operario et al. (2014)	Diagnostic interviewing is an informative tool to understand behavioural health risks for transgender women including sexual practices, SU^b, and co-occurring behavioural risks. Continuity of care between primary health care providers and therapists is paramount to support the person’s mental and physical wellbeing.	Associations between unprotected sex, alcohol, and drug use in this population require multicomponent interventions that address health disparities in this community. On a structural level, efforts to reduce stigma toward transgender populations are highly warranted and demand research and policy attention.
Reisner et al. (2015)	Social psychological mechanisms where stigma arises in health care utilisation and the treatment process is valuable information for clinicians to gather. These processes help understand the lived experiences and support treatment outcomes of trans-masculine people.	Expanding beyond anticipated and enacted stigma may provide researchers a better understanding of motivations and outcomes related to SU within a trans-masculine population. Uncover the social psychological mechanisms through which stigma influences healthcare utilisation for trans masculine people, researchers, practitioners and policymakers can intervene to increase cultural competence in clinical settings and healthcare delivery systems.
Kidd et al. (2019)	Persistent risky drinking for transgender individuals is associated with gender dysphoria. Clinicians may inquire about the relationship for these two aspects when working with transgender clients, as the direction between these subjects is unclear.	Future research is needed to further investigate the relationships between minority stress and identity development from a longitudinal lens. This work will inform the development of culturally-tailored therapeutic interventions for risky drinking among transgender people.
Benz et al. (2019)	In a nonjudgmental, LGBTQ+^c affirming space, clinicians may inquire about individuals’ barriers to receive treatment once in treatment in order to understand treatment process and client’s desired treatment outcomes.	Future researchers may conceptualise SU stigma as both a barrier and motivator for treatment. The role of SU stigma should be more finitely understood for specific LGBTQ+ individuals, as this stigma may not uniformly be associated with treatment utilisation across LGBTQ+ subgroups.
Felner et al. (2020)	Treatment providers should address clients’ SU and their LGBTQ+identities and experiences with related stressors and sociocultural contexts and adopt culturally humble and LGBTQ+ affirming treatment approaches. Providers should stay updated of current LGBTQ+ rights–related policies; providers should discuss with LGBTQ+ clients their current social support networks and the role of sub stance use in social interactions. Treatment environments should be welcoming to LGBTQ+ people (e.g. providing gender-neutral restrooms and LGBTQ+ specific reading materials).	Larger samples of gender-minority individuals with SUDs^d should be included in future studies to understand stressors in relation to one’s sociocultural context, SU, and coping. Nuances between gender identity and sexual orientation should be included in future studies as both groups may have unique experiences and outcomes.
Lee et al. (2020)	The role of ACEs^e and exposure to SU-oriented social environments may be beneficial for clinicians to understand GSM individual’s relationship with substances, mental health disorders, and psychosocial distress (e.g. discrimination and harassment).	Risks and resiliencies are universal (e.g. mental health) and GSM specific (e.g. GSM-targeted discrimination). Policy makers and future researchers may allocate attention to substance-free social environments to support GSM health.
Matsuzaka (2018)	Clinicians should provide psychoeducation around the risks and benefits of transgender and gender non-conforming individuals in the participation of AA^f for sobriety and gender transitions as this may be a beneficial treatment modality, however, there is risk of microaggressions and harassment within AA treatment.	Researchers, policies, and agencies may better serve TGNC^g adults with SUDs by promoting greater inclusivity through removal of procedures that marginalise TGNC individuals. Trans-affirmative care can be worked towards by updating screening and assessment forms, and professionals checking personal biases against TGNC individuals.
Penn et al. (2013)	Clinicians may integrate two themes from this research in their care with sexual minority clients: the pink elephant in the room (i.e. the role of sexual identity in therapy), and searching for an authentic, holistic, approach in treatment (i.e. a desire for mental health, substance misuse, and other issues to be interrelated in treatment).	Future research should identify national prevalence rates of LGBTQ+ substance misuse diagnosed with co-occurring mental health disorders and SUDs. Future research may focus on treatment utilisation for LGBTQ+ individuals to identify treatment needs of this group.
Cochran et al. (2007)	Empirical evidence from this study suggests Latino and Asian American individuals of gender and sexual minority status have been at risk for psychiatric morbidity. This information is relevant to culturally humble therapeutic care.	These findings underscore the emphasis on future quality research focused on dual minority status individuals (e.g. race and ethnicity / gender and sexual orientation) to inform future treatment interventions.
Green (2011)	Motivational interviewing techniques and knowledge of current research related to LGBT treatment utilisation may minimise potential risks and barriers to change. Therapists should spend time exploring previous treatment experiences and perceptions that could prevent an individual from engaging fully in treatment. Choosing goals for drinking patterns warrants a discussion within the treatment process.	Anecdotally, clients and therapists may prefer to match based on similar identities. The findings of the present study did not support this finding. Future research may explore this hypothesis further to identify motivations for client-therapist matching versus no preference. Public health campaigns should address motivation issues and drinking norms which could stimulate treatment seeking from individuals who minimise their drinking or experience specific motivational barriers to changing their drinking habits.
Lukowski et al. (2016)	Clinicians working with young adults and youth may explore the process of ‘coming out’ both outside and within the therapeutic context and in relation to their smoking behaviours, as LGBT youth begin smoking at a younger age than their heterosexual counterparts.	LGBT-targeted anti-smoking interventions should occur earlier in life than that of heterosexual counterparts. Future studies may focus on racial, sexual, and gender minorities by leveraging national data sets.

^a GSM: gender or sexuality minority.

^b SU: Substance Use.

^c LGBTQ+: lesbian, gay, bisexual, transgender, queer, questioning or otherwise gender or sexuality minority;

^d SUD: Substance Use Disorder;

^e ACE: Adverse Childhood Experiences;

^f AA: Alcoholics Anonymous;

^g TGNC: transgender and gender nonconforming.

Implications for research

Our comprehensive review findings, primarily focused on the U.S., have profound implications for supporting and tailoring future research funding strategies in the topic of LGBTQ+ and SU treatment to foster a more globally inclusive and diverse approach to understanding the complex intersectionality of stigma, SU, help-seeking behaviours, treatment disparities and needs among LGBTQ+ individuals in the U.S. This review suggested that future research should consider exploring the relationships between minority stress, identity development, and SU treatment utilisation longitudinally with larger samples from diverse backgrounds or leverage national datasets to better understand how intersectional stigma could long-term impact LGBTQ+ individuals’ SU and coping under minority stressors. It is important for future studies to help identify the ‘best timing’ and duration for interventions to reduce stigma, promote culturally tailored therapeutic interventions, and improve SU treatment outcomes for LGBTQ+ individuals.

Secondly, there is a need to investigate how the intersections of multiple minority identities (e.g. race, gender, sexuality, SU behaviours) may affect SU treatment outcomes. Especially, researchers should consider exploring SU treatment utilisation and treatment barriers among bisexual and transgender individuals within the LGBTQ+ communities, where stigma may not uniformly be associated with treatment utilisation across all LGBTQ+ subgroups. This review also highlighted that future research should consider conceptualising SU stigma as both a barrier and motivator in SU treatment, which may inform future treatment interventions to better serve those gender and sexuality minorities with SUDs and co-occurring disorders.

Further, research should consider exploring interventions that could promote greater inclusivity through the removal of procedures that marginalise GSM individuals (e.g. update screening and assessment forms). Additionally, future researchers should consider developing effective interventions (e.g. use inclusive languages) and innovative research designs (e.g. use photovoice, virtual reality simulations, collaborate with LGBTQ+ community members) to reduce stigma and increase access to culturally competent SU treatment to better serve LGBTQ+ individuals.

Moreover, future research should include discussions on positive experiences/factors that contribute to successful outcomes (e.g. universal resilience). As many studies have explored and discussed treatment barriers, identifying protective factors and their influences on positive outcomes could promote better practices in treatment and may potentially transform future training programmes’ development for healthcare professionals. Lastly, review findings also revealed that both clients and therapists may prefer to be matched based on similar identities which suggests an important area that could help identify potential motivations for client-therapist matching and influences on treatment outcomes. A summary of implications for research, see Table 6.

Implications for policy

This review suggested that policy makers should allocate attention to creating and supporting substance-free social environments to promote health and well-being of LGBTQ+ individuals by providing more funding to programmes recognise biases towards LGBTQ+ communities and address LGBTQ+ cultural competence topics. Supporting these programmes (e.g. sports, festivals, events that do not involve SU) will help enhance people’s awareness of social biases towards this minority group, foster a sense of community belonging, and reduce their minority stress.

Secondly, policy makers should consider implementing educational campaigns that promote public understanding of GSM identities. Clinical professional practice boards/organisations should provide regular free-of-charge training opportunities to healthcare professionals and organisations in order to improve their care for LGBTQ+ communities. Regulations that require this specialised training should be utilised as part of their licensure renewal requirements and government funding support. Moreover, policy makers should consider modifying their current polices to reduce stigma towards LGBTQ+ individuals and implement anti-discrimination laws to protect them from discrimination and unfair treatment in employment, housing, and public accommodations.

Additionally, policy makers should increase funding opportunities for research projects that explore the intersectional stigma on SU treatment among LGBTQ+ communities, which can help to build effective interventions and preventions of SUDs in this populations. In turn, government-funded research projects findings could be used to inform policy developments to address unique needs and challenges that LGTBQ+ faced in SU treatment. Furthermore, policy makers should consider utilising their power and influence to promote healthy behaviours through public advertisements (e.g. radio, billboards) to reduce cultural acceptance of SU and encourage mental health and SU treatment. Lastly, policy makers should consider improving current public insurance benefits coverage to allow more individuals who depend on public insurance (e.g. Medicaid, Medicare) to promote equitable access to SU treatment without increased financial burdens. A summary of implications for policy, see Table 6.

Limitations

Although this review has many strengths, it has limitations that should be considered. First, to be considered and included in this scoping review, articles must be published in a peer-reviewed journal and indexed in the eight databases that authors searched for this review. This limited search scope may lead to the overlook of some articles that was not able to have a chance for publications, especially those with non-significant findings which tend to be less published. As a result, the research team may not capture all relevant research studies on the topic.

Second, studies included in this scoping review must be published in English and have a study or treatment setting in the U.S. in order to be analysed for this review, which may result in a miss of valuable literature published in other languages or conducted outside of the U.S. Additionally, even though the authors conducted a quality assessment using QATSDD, this quality assessment tool heavily relies on the competency and expertise of each reviewer in evaluating all quality characteristics to enable fair and consistent assessment, which may vary within the study team. Lastly, findings from this scoping review may not be generalised to all LGBTQ+ individuals as our twelve included articles vary in their focused populations which may not apply to some specific subgroups.

Conclusion

Our scoping review provided a comprehensive analysis on the topic by looking at existing literature and provided suggestions on implications within the U.S. It is essential to acknowledge that the impact of intersectional stigma on SU treatment among LGTBQ+ individuals is a complex and important topic that requires attention from professionals, researchers, and policy makers to better understand the phenomenon and to develop effective interventions to reduce stigma and enhance treatment outcomes.

Acknowledgements

We extend our gratitude to Dr. Cecilia Mengo for providing feedback to improve the quality of this manuscript. Authors’ Contributions: YX and AKD designed and conceptualised the study topic. YX and MRW conducted article screening and quality assessment. YX and CMS summarised content into tables. All authors contributed to the writing of this manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).