Illness Perceptions, Cognitions, and Beliefs on COPD Patients’ Adherence to Treatment – A Systematic Review

Figures & data

Table 1 Illness Inclusion and Exclusion Criteria

Criterion	Inclusion	Exclusion
Time	From inception to 1st February 2023	Studies outside these dates
Language	English (the recognized language of international scientific debate)	Non-English
Type of Article	Original research, published in a peer review journal. Qualitative or quantitative studies (Randomized Control Trials, Case Control Studies, Cross-Sectional Studies, Longitudinal Studies);	Articles that were not peer-reviewed, only abstracts available; grey literature; review; systematic review; narrative review; scoping review; meta-analysis; commentaries, letter, editorial
Ethics Clearance	Studies with approved ethics notification	Studies without approved ethics notification
Study Focus	Adherence to therapies (pharmacological therapies/Non-Invasive Ventilation (NIV)/Long Term Oxygen Therapy (LTOT), Pulmonary Rehabilitation (PR), etc) and its relationship with illness perceptions	Studies that do not consider the outlined relationship
Literature Focus	Studies that discuss the patient’s point of view and his/her experience, beliefs, and perceptions, studies that present a clear theoretical framework on the patients’ experience, studies that focus on the experience of using the treatment, in the context of chronic pathologies considered	Articles that did not make a passing or token reference to illness perceptions about therapies. The caregiver’s and/or physicians’ point of view
Population and Sample	Chronic Obstructive Pulmonary Disease (COPD)	All the other chronic diseases

Table 2 Detailed Search Strategy

Database	Mesh Terms Combination	Filters
PubMed	“COPD” OR “Chronic Obstructive Pulmonary Disease*”) AND ‘Illness perception’ OR ‘Illness cognition’ OR ‘Illness belief’ AND (“adherence” OR “compliance”) AND (“NIV” OR “Non Invasive Ventilation” OR “Oxygen Therapy” OR “Long Term Oxygen Therapy” OR “pharmacological therapy” OR “medication*” OR “bronchodilator*” OR “inhalator*”	Humans; English; Full Text; Clinical Study; Clinical Trial; Controlled Clinical Trial; Meta Analysis; Observational Study; Randomized Controlled Trial; Review; Systematic Review; Comparative Study;
Medline	“COPD” OR “Chronic Obstructive Pulmonary Disease*”) AND ‘Illness perception’ OR ‘Illness cognition’ OR ‘Illness belief’ AND (“adherence” OR “compliance”) AND (“NIV” OR “Non Invasive Ventilation” OR “Oxygen” OR “Oxygen Therapy” OR “Long Term Oxygen Therapy” OR “LTOT” OR “therapy” OR “pharmacological therapy” OR “medication*” OR “bronchodilator*” OR “inhalator*”	N.A.
Scopus	“COPD” OR “Chronic Obstructive Pulmonary Disease*”) AND ‘Illness perception’ OR ‘Illness cognition’ OR ‘Illness belief’ AND (“adherence” OR “compliance”) AND (“NIV” OR “Non-Invasive Ventilation” OR “Oxygen” OR “Oxygen Therapy” OR “Long Term Oxygen Therapy” OR “LTOT” OR “therapy” OR “pharmacological therapy” OR “medication*” OR “bronchodilator*” OR “inhalator*”	Human/Humans; English; Article; Review; Journal; Psychology; Health Professions; Chronic Obstructive Lung Disease
ResearchGate	“COPD” OR “Chronic Obstructive Pulmonary Disease” AND ‘Illness perception’ OR ‘Illness cognition’ OR ‘Illness belief’ AND (“adherence” OR “compliance”) AND (“NIV” OR “Non-Invasive Ventilation” OR “Oxygen” OR “Oxygen Therapy” OR “Long Term Oxygen Therapy” OR “LTOT” OR “therapy” OR “pharmacological therapy” OR “medication*” OR “bronchodilator*” OR “inhalator*”	English; Article; Review
PsycINFO	“COPD” OR “Chronic Obstructive Pulmonary Disease*”) AND ‘Illness perception’ OR ‘Illness cognition’ OR ‘Illness belief’ AND (“adherence” OR “compliance”) AND (“NIV” OR “Non-Invasive Ventilation” OR “Oxygen” OR “Oxygen Therapy” OR “Long Term Oxygen Therapy” OR “LTOT” OR “therapy” OR “pharmacological therapy” OR “medication*” OR “bronchodilator*” OR “inhalator*”	Humans; English
Cochrane Library	“COPD” OR “Chronic Obstructive Pulmonary Disease*”) AND ‘Illness perception’ OR ‘Illness cognition’ OR ‘Illness belief’ AND (“NIV” OR “Non-Invasive Ventilation” OR “Oxygen Therapy” OR “Long Term Oxygen Therapy” OR “therapy” OR “pharmacological therapy” OR “medication*” OR “bronchodilator*” OR “inhalator*”	English; Trials; Review

Figure 1 Risk of bias.

Figure 2 Study selection process – eligibility graph.

Table 3 Study Characteristics

ID	Citation (APA)	Author(s)	Publication Year	Journal	Search Engine	Key Words	Country	I/E Criteria	Sample (N, Gender, Age)	AIM -Research Question	Variables	Study Design	Main Outcome (Our Interest)	Secondary Outcome	Tool(s)	Analysis	Drop Out	Conclusion
1	Krauskopf, K., Federman, A. D., Kale, M. S., Sigel, K. M., Martynenko, M, O’Conor, R, and Wisnivesky, J. P. (2015). Chronic obstructive pulmonary disease illness and medication beliefs are associated with medication adherence. COPD: Journal of Chronic Obstructive Pulmonary Disease, 12(2), 151–164.	Krauskopf, K., Federman, A. D., Kale, M. S., Sigel, K. M., Martynenko, M, O’Conor, R, and Wisnivesky, J. P.	2015	COPD: Journal of Chronic Obstructive Pulmonary Disease	PubMed	Health beliefs, outcomes, self-management, vulnerable population	USA	Participants were excluded if they solely used as-needed bronchodilators, or did not use any COPD medication	188, 62 males (33%), 67 (62–74)	1) to further characterize illness and medication beliefs in patients with COPD; 2) to assess the association of these beliefs with self-reported adherence to medications.	1) Illness beliefs; 2) Medication beliefs; 3) self-reported adherence to medication;	Cross-Sectional Study	Non-adherent participants reported being more concerned about their COPD (p = 0.011; Cohen’s d = 0.43), more emotionally affected by the disease (p = 0.001; Cohen’s d = 0.54), and had greater concerns about COPD medications (p < 0.001, Cohen’s d = 0.81). In adjusted analyses, concerns about COPD medications independently predicted non-adherence (odds ratio: 0.52, 95% confidence interval: 0.36–0.75). In this cohort of urban minority adults, concerns about medications were associated with non-adherence.	n.a.	1) Brief Illness Perception Questionnaire (B-IPQ); 2) Beliefs about Medications Questionnaire (BMQ); 3) Medication Adherence Report Scale (MARS)	Logistic regression analysis	x	Identifying mechanisms that reinforce and improve medication adherence in patients with COPD will likely improve disease-related outcomes.
2	Brandstetter, S., Finger, T., Fischer, W., Brandl, M., Böhmer, M., Pfeifer, M., and Apfelbacher, C. (2017). Differences in medication adherence are associated with beliefs about medicines in asthma and COPD. Clinical and Translational Allergy, 7(1), 1–7.	Brandstetter, S., Finger, T., Fischer, W., Brandl, M., Böhmer, M., Pfeifer, M., and Apfelbacher, C.	2017	Clinical and Translational Allergy	Scopus	Medication adherence, Compliance, Beliefs about medicines, Asthma, COPD, Chronic obstructive lung diseases	Germany - EU	Patients were eligible for participation in the study if asthma or COPD had been diagnosed by a physician at least 3 months ago, if they were adults, if they had sufficient knowledge of German and if they had no mental disorder (except affective disorders or anxiety).	206, 125 males (60.7%), 65.3 (8.85)	1) to examine the associations between beliefs about medicines and self-reported medication adherence in people with chronic obstructive lung disease	1) Medication beliefs; 2) self-reported adherence to medication;	Cross-Sectional Study	34% of COPD patients were completely adherent to their prescribed medication: specific beliefs about the necessity of medicines were positively associated with medication adherence in patients	- health related quality of life, Short Form Health Survey (SF-12) - anxiety and depression, Hospital Anxiety and Depression Scale (HADS) -self-efficacy, Generalized Self-Efficacy Scale (GSE), - COPD control, COPD assessment test (CAT)	1) Beliefs about Medications Questionnaire (BMQ); 2) Medication Adherence Report Scale (MARS)	Multivariable logistic regression models were computed for all five BMQ-subscales.	x	This study demonstrated high rates in medication non-adherence in patients with chronic obstructive lung disease. Beliefs in the specific necessity of prescribed medications were found to be associated with medication adherence in patients with COPD and suggest a modifiable target for improving patient–doctor consultations when prescribing medicines
3	Duarte-de-Araújo, A., Teixeira, P., Hespanhol, V., and Correia-de-Sousa, J. (2018). COPD: understanding patients’ adherence to inhaled medications. International journal of chronic obstructive pulmonary disease, 13, 2767.	Duarte-de-Araújo, A., Teixeira, P., Hespanhol, V., and Correia-de-Sousa, J. (2018).	2018	International journal of chronic obstructive pulmonary disease	MedLine	COPD, adherence, inhaled medications, adherence behaviors, beliefs	Portugal - EU	Stable patients over 40 years old and diagnosed as suffering from COPD according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria were consecutively included.13 Exclusion criteria were refusal to participate and an inability to understand simple questionnaires.	319, 249 males (78.1), 67.7±10.26	1) to assess whether demographic variables, clinical and functional severity of COPD, and beliefs about inhaled medications are associated with patients’ adherence to inhaled medications.	1) Medication beliefs; 2) self-reported adherence to medication;	Cross-Sectional Study	The mean BMQ Necessity score was higher in adherent patients (P=0.000), but the mean Concern score was similar for both (P=0.877).	n.a.	1) the Beliefs about Medications Questionnaire (BMQ); 2) The Measure of Treatment Adherence (MTA),	Binary logistic regression	x	Adherence is related to need perception and to the functional severity of the disease. A non-adherent patient is usually a current smoker with lower degree of airflow limitation and lower perception of medication necessity. New information obtained was related to the patterns and reasons for different adherence behaviors, which are based on three major groups of patient related-determinants: health-related experiences, health-related behaviors and health-related beliefs.
4	Agarwal, P., Lin, J., Muellers, K., O’Conor, R., Wolf, M., Federman, A. D., and Wisnivesky, J. P. (2021). A structural equation model of relationships of health literacy, illness and medication beliefs with medication adherence among patients with chronic obstructive pulmonary disease. Patient education and counseling, 104(6), 1445–1450.	Agarwal, P., Lin, J., Muellers, K., O’Conor, R., Wolf, M., Federman, A. D, and Wisnivesky, J. P.	2021	Patient education and counseling	Scopus	COPD, Health literacy, Medication beliefs and adherence, Structural equation models, COPD illness	USA	We recruited community-dwelling, English or Spanish-speaking adults ≥55 years with physician-diagnosed COPD. Patients were excluded if they had asthma or another chronic respiratory illness, dementia, or other neurological and psychological conditions that would profoundly affect cognition (eg, stroke, advanced Parkinson’s disease, schizophrenia).	393, 114 males, 67.23 + 8.06	1) to examine the pathways linking Health Literacy, through medications and illness beliefs, with COPD medication adherence	1) Medication and illness beliefs; 2) self-reported adherence to medication; 3) health literacy	Cross-Sectional Study	Those with low medication adherence had higher BIPQ illness score (45 [39, 51] vs 42 [34, 50], p = 0.01) and medication concern score (14 [10,18] vs 11 [10,14], p < 0.0001) as compared to those who were adherent to the medications.	- No association was observed between HL and overall illness beliefs (p = 0.08). - there were differences among individual illness belief scores. Individuals with limited HL were more likely to report that COPD affected their life (7 [5,9] vs 6 [4,8], p < 0.001), they experience more symptoms from COPD (7 [5,10] vs 6 [4,8], p < 0.001), and they think that COPD affects them emotionally (7 [4,10] vs 6 [3,9], p = 0.03). - Low adherence to COPD medications was observed among 208 subjects (53%). Participants with limited HL were more likely to have low medication adherence than those with adequate HL (67% vs 49%, p < 0.0001; Table 3)	1) B-IPQ; B;MQ 2) Medication Adherence Rating Scale (MARS); 3) Short Test of Functional Health Literacy in Adults (S-TOFHLA)	Chi-squared tests and Wilcoxon rank sum tests	x	n.a.
5	Olszanecka-Glinianowicz, M., and Almgren-Rachtan, A. (2014). The adherence and illness perception of patients diagnosed with asthma or chronic obstructive pulmonary disease treated with polytherapy using new generation Cyclohaler. Advances in Dermatology and Allergology/Postępy Dermatologii i Alergologii, 31(4), 235–246.	Olszanecka-Glinianowicz, M., and Almgren-Rachtan, A.	2014	Advances in Dermatology and Allergology/Postępy Dermatologii i Alergologii	Research Gate	Asthma; chronic obstructive pulmonary disease; adherence; polytherapy; new generation C	Poland (EU)	The inclusion criteria were age ≥ 18 years, diagnosis of asthma or COPD, current polytherapy with fluticasone propionate and formoterol fumarate using the Fantasmino inhaler at least 14 days prior to enrollment. The exclusion criteria included age below 18 years, inability to obtain the patient’s answers to the questions included in the survey, patient’s refusal	2602, 1491 males (52.3%), 60.0 ±13.5	1. To assess the adherence in patients diagnosed with asthma and COPD treated with polytherapy with fluticasone propionate and formoterol fumarate using the Fantasmino inhaler in relation to primary diagnosis and illness perception. 2. To assess patients’ and doctors’ opinion about this form of therapy.	1) Adherence to medication; 2) Illness perception	Observational study	During the observation, the adherence rate increased significantly in the COPD group (61.5% vs.73.0%; p < 0.01). A negative correlation between total MMAS-8 and BIPQ scores was observed (R = –0.15; p < 0.001).	During the observation, a percentage of patients who believed that the administration of the two drugs in a single inhaler considerably facilitates their use increased significantly in both study groups. In addition, an increased percentage of doctors believed that this therapeutic option facilitated education of patients and decreased the number of errors made by the patients.	1) MMAS-8; 2) B-IPQ	Separate groups were compared using the χ2 test and χ2 test for trend and T-test. The assessment of associations between variables was done with Spearman correlation	x	The illness perception, younger age, disease duration and severity are predictors of adherence to treatment with fluticasone propionate and formoterol fumarate using the Fantasmino inhaler among patients with asthma and COPD. The positive opinion of patients and doctors about administration of fluticasone propionate and formoterol fumarate using the Fantasmino inhaler increased during observation.
6	Khdour, M. R., Hawwa, A. F., Kidney, J. C., Smyth, B. M., and McElnay, J. C. (2012). Potential risk factors for medication non-adherence in patients with chronic obstructive pulmonary disease (COPD). European journal of clinical pharmacology, 68(10), 1365–1373.	Khdour, M. R., Hawwa, A. F., Kidney, J. C., Smyth, B. M., and McElnay, J. C.	2012	European journal of clinical pharmacology	MedLine	Adherence; COPD; Health beliefs; Depression; Self-efficacy; Disease knowledge	Ireland	IC: confirmed diagnosis of COPD for at least 1 year, having an FEV1 value of 30–80% of the predicted normal value and being over 45 y.o. Patients who had a hf, moderate to severe learning difficulties, severe mobility problems, terminal illness or who had attended a pulmonary rehabilitation programme in the last 6 months were excluded from the study.	173, 75 males (43.4%), 66.6 (9.7)	1) To investigate the effect of a range of demographic and psychosocial variables on medication adherence in chronic obstructive pulmonary disease (COPD) patients managed in a secondary care setting.	1) self-reported adherence to medication; 2) Depression; 3) COPD knowledge; 4) Health beliefs; 5) COPD self-efficacy; 6) Medication effectiveness	Cross-Sectional Study	Participants were aged 67±9.7 (mean ± SD) years, 56% female and took a mean (SD) of 8.2±3.4 drugs. Low adherence with medications was present in 29.5% of the patients. Demographic variables (gender, age, marital status, living arrangements and occupation) were not associated with adherence. A range of clinical and psychosocial variables, on the other hand, were found to be associated with medication adherence, ie beliefs regarding medication effectiveness, severity of COPD, smoking status, presence of co-morbid illness, depressed mood, self-efficacy, perceived susceptibility and perceived barriers within the HBM (p<0.05).	n.a.	1) Morisky scale; 2) Hads-D; 3) COPD knowledge questionnaire; 4) Health beliefs model questionnaire; 5) COPD self-efficacy questionnaire; 6) Medication effectiveness (interview)	Binary stepwise conditional logistic regression analysis	x	Adherence in COPD patients is influenced more by patients’ perception of their health and medication effectiveness, the presence of depressed mood and co-morbid illness than by demographic factors or disease severity.
7	López-Pintor, E., Grau, J., González, I., Bernal-Soriano, M. C., Quesada, J. A., and Lumbreras, B. (2021). Impact of patients’ perception of COPD and treatment on adherence and health-related quality of life in real-world: study in 53 community pharmacies. Respiratory Medicine, 176, 106,280.	López-Pintor, E., Grau, J., González, I., Bernal-Soriano, M. C., Quesada, J. A., and Lumbreras, B.	2021	Respiratory Medicine	Research Gate	Chronic obstructive pulmonary disease; Adherence; Persistence; Inhaler medication; Health-related quality of life	Spain (UE)	COPD patients, adult patients	318, 239 males, 71.32 (9.24)	1) We aimed to assess the impact of patients’ perception of their treatment and disease on adherence and Health-Related Quality of Life (HRQL) in patients attending a community pharmacy, where usually subjects have a better condition than those in clinical settings.	1) Adherence to inhaled medication; 2) persistence; 3) Health related quality of life; 4) treatment perception	Cross-Sectional Study	SGRQ score was significantly worse in patients with intermediate/poor adherence (p = 0.036) and in those who thought the inhaler’s effectiveness was fair/poor (p < 0.001).	Persistence was achieved by 78.6% of the patients and 58.5% had good adherence. Patients having a multidose DPI and those with MDI showed a 2.8-fold and 4.1-fold increased association, respectively, with intermediate/poor adherence in comparison with those having a single dose DPI. Those patients who did not have knowledge about COPD (aOR 2.106, p = 0.006) and those who thought that the inhaler effectiveness was fair/poor (aOR 2.361, p = 0.006) were more likely to have intermediate/poor adherence.	1) Test of Adherence to Inhalers test; 2) persistence interview; 3) St George’s Respiratory Questionnaire (SGRQ); 4) treatment perception interview	Logistic regression	x	The type of inhaler and patients’ knowledge and perceptions of their disease and treatment were associated with good adherence and higher HRQL. Clinicians should promote shared-decision making in the choice of inhaler depending on patients’ individual abilities and beliefs.
8	Koehorst-ter Huurne, K., Brusse-Keizer, M., Van Der Valk, P., Movig, K., Van Der Palen, J., and Bode, C. (2018). Patients with underuse or overuse of inhaled corticosteroids have different perceptions and beliefs regarding COPD and inhaled medication. Patient preference and adherence, 12, 1777.	Koehorst-ter Huurne, K., Brusse-Keizer, M., Van Der Valk, P., Movig, K., Van Der Palen, J., and Bode, C.	2018	Patient preference and adherence	PubMed	COPD; adherence; illness perceptions; medication beliefs; in-depth interviews	Netherlands (UE)	In order to study nonadherence, 10 patients who underused and 10 patients who overused their ICS were selected from the COMIC cohort and were invited for an in-depth interview.	20, 10 males (50%), 60.5	1) To study perceptions and beliefs regarding COPD and inhaled medication in COPD patients with poor adherence.	1) Adherence to medication; 2) Illness perception according to IRM- Leventhal	Cross-Sectional Study	Overusers and underusers showed a different pattern in perceptions and beliefs regarding inhaled medication and COPD.	(see the Illness representation Model −5 sections answers to the semi-structured interview)	1) patients’ pharmacy records; 2) semistructured in-depth interviews, about mental and physical health, illness perceptions, knowledge regarding COPD, and experience with, knowledge of, and acceptance of COPD medication and inhalation devices	x	x	Non-adherence in COPD is a multifactorial problem encompassing behavioral issues possibly caused by perceptions and knowledge of patients. Underusers and overusers showed a different pattern in perceptions and beliefs on inhaled medication.
9	Homętowska, H., Świątoniowska-Lonc, N., Klekowski, J., Chabowski, M., and Jankowska-Polańska, B. (2022). Treatment Adherence in Patients with Obstructive Pulmonary Diseases. International Journal of Environmental Research and Public Health, 19(18), 11,573.	Homętowska, H., Świątoniowska-Lonc, N., Klekowski, J., Chabowski, M., and Jankowska-Polańska, B	2022	International Journal of Environmental Research and Public Health	PubMed	Treatment adherence; compliance; chronic obstructive pulmonary disease; beliefs	Poland (EU)	The inclusion criteria were as follows: provision of informed written consent to take part in the study, diagnosis of an obstructive pulmonary disease, patients aged over 18, patients who had been using at least one inhaled medication for at least 6 months, cognitive status sufficient to understand the purpose and methods of the study and complete questionnaires	325, 166 males (51.08%), 63 ± 11	1) The aim of the study was to evaluate the level of treatment adherence to inhaled therapy in patients with obstructive pulmonary diseases.	1) beliefs about medications; 2) adherence to medication	Cross-Sectional Study	The patients were uncertain about the overuse of medicines by doctors (a mean of 3.19 points per question) and about the harmful effects of medicines (a mean of 2.82 points per question) and did not know if they were concerned about taking their medication (a mean of 3.33 points per question) (Table 2). The respondents tended to be convinced of the necessity of their medication (a mean of 3.87 points per question). king medications as prescribed (13.41 ± 4.44) and adherence to refills on schedule (7.74 ± 2.21). A total of 74.15% of patients demonstrated sporadic non-compliance, 59.69% exhibited deliberate non-compliance and 11.38% exhibited unconscious non-compliance with inhaled medications.	Belief that medicines are overused by doctors, belief that medicines are harmful and concerns about medicines were significantly (p < 0.05) and positively (r > 0) correlated with the total ARMS score and the two subscales of the ARMS. Therefore, the greater the belief that medicines are overused by doctors, the lower the level of adherence (the higher the score on the ARMS) in all dimensions (Table 2). Belief that medicines are overused by doctors was significantly (p < 0.05) and negatively (r < 0) correlated with the lack of sporadic, deliberate and unconscious non-compliance. Belief in the necessity of medication was significantly (p < 0.05) and positively (r > 0) correlated with the lack of sporadic and unconscious non-compliance and was significantly and negatively (r < 0) correlated with the total ARMS score and the two subscales of the ARMS. Therefore, the stronger the belief in the necessity of medication, the higher the level of adherence (the lower the score) in all dimensions. Belief that medicines are harmful and concerns about medicines were significantly (p < 0.05) and negatively (r < 0) correlated with the lack of sporadic, deliberate and unconscious non-compliance. Therefore, the greater the concerns about medicines, the poorer the adherence to inhaled medications.	1) Beliefs about Medicines Questionnaire, 2) Test of Adherence to Inhalers and Adherence to Refills and Medications Scale.	Linear regression	x	The number of hospital admissions due to exacerbations of the disease over the last year and belief that medicines are harmful are independent determinants of poorer medication adherence.
10	Pierobon, A., Bottelli, E. S., Ranzini, L., Bruschi, C., Maestri, R., Bertolotti, G, and Giardini, A. (2017). COPD patients’ self-reported adherence, psychosocial factors and mild cognitive impairment in pulmonary rehabilitation. International journal of chronic obstructive pulmonary disease, 12, 2059.	Pierobon, A., Bottelli, E. S., Ranzini, L., Bruschi, C., Maestri, R., Bertolotti, G, and Giardini, A.	2017	International journal of chronic obstructive pulmonary disease	Scopus	Depression; anxiety; mild cognitive impairment; adherence; COPD; pulmonary rehabilitation	Italy (UE)	The exclusion criteria were severe medical conditions that did not allow assessment, no Italian education or relapse into illiteracy, severe visual-perceptive deficits, low subjective motivation or refusal to undergo the evaluation, severe psychiatric disorders and severe cognitive deterioration	117, 63 males (75%), 70.2 (7.0)	1) The aims of the study were to describe a COPD population in a rehabilitative setting as regards the patients depressive symptoms, anxiety, mild cognitive impairment (MCI) and self-reported adherence and to analyze their relationships; to compare the COPD sample MCI scores with normative data; and to investigate which factors might predict adherence to prescribed physical exercise	1) depression; 2) anxiety; 3) MCI; 4) self-reported adherence; 5) disease perception and self-efficacy in following medical prescriptions	Obstervational cross-sectional study	They struggled with disease acceptance (30.9%) and disease limitations acceptance (28.6%). Most of them received good family (89%) or social (53%) support. Non-pharmacological adherence, depression, anxiety and MCI showed significant relations with 6-minute walking test, body mass index (BMI) and GOLD.	Depression was related to autonomous long-term oxygen therapy modifications, disease perception, family support and MCI. In the multivariate logistic regression analysis, higher BMI, higher depression and lower anxiety predicted lower adherence to exercise prescriptions (P=0.0004, odds ratio =0.796, 95% CI =0.701, 0.903; P=0.009, odds ratio =0.356, 95% CI =0.165, 0.770; and P=0.05, odds ratio =2.361, 95% CI =0.995, 5.627 respectively).	1) HADS; 2) HADS;3) MMSE, MOCA 4) MGL adherence scale; 5)asicold-r	Linear regression	x	In COPD patients, focusing on pharmacological and non-pharmacological adherence enhance the possibility of tailored pulmonary rehabilitation programs.
11	Baiardini, I., Contoli, M., Corsico, A. G., Scognamillo, C., Ferri, F., Scichilone, N, and Braido, F. (2021). Exploring the relationship between disease awareness and outcomes in patients with chronic obstructive pulmonary disease. Respiration, 100(4), 291–297.	Baiardini, I., Contoli, M., Corsico, A. G., Scognamillo, C., Ferri, F., Scichilone, N, and Braido, F.	2021	Respiration	Research Gate	Awareness; Chronic obstructive pulmonary disease; Adherence; Patient-reported outcomes	Italy (UE)	COPD patients, adult patients	367, 74.2% males, 72.0 (67.0–77.0)	1) The aim of this analysis was to explore the association between COPD optimal and suboptimal awareness, clinical parameters, and the following patient-reported outcomes: modified Medical Research Council (mMRC), Treatment Satisfaction Questionnaire (TSQM-9), COPD Assessment Test (CAT), Morisky Medication-Taking Adherence Scale (MMAS-4), and Brief Illness Perception Questionnaire (B-IPQ).	1) Treatment satisfaction; 2) Medication adherence; 3) Illness perception	Cross-Sectional Study	At enrollment, no difference between the 2 groups was found in terms of age, age at COPD diagnosis, and MMAS scores. Overall, patients with suboptimal awareness, compared to those in which awareness was optimal, had a higher median CAT score (difference: 5.0 points; p value = 0.0001), a higher median mMRC score (difference: 1.0 point; p value = 0.0031), a lower median duration of COPD (difference: 1.4 years; p value = 0.0428), a lower median TSQM-9 effectiveness score (difference: 5.6 points; p value = 0.0002), a lower median TSQM-9 convenience score (difference: 11.1 points; p value < 0.0001), a lower median TSQM-9 global satisfaction score (difference: 14.3 points; p value < 0.0001), and a higher median B-IPQ total score (difference: 9.0 points; p value < 0.0001).	At enrollment, the proportion of patients who had exacerbations during the previous year was higher in patients with suboptimal COPD awareness (DACQ total score <80) than in those with an optimal level of awareness (42.8 vs.21.4%, p value = 0.0009). At the 12-month follow-up, the proportion of patients with an optimal awareness (DACQ total score ≥80) was significantly higher in the group of those with CAT <10 than in the group of those with CAT ≥10 (p = 0.0022)	1) Treatment satisfaction Questionnaire; 2)MMAS-4; 3)B-IPQ	Linear regression	x	The results of our post hoc analysis suggest that patients’ awareness of their COPD disease is related to both clinical outcomes and how they perceive and manage their condition.
12	Contoli, M., Rogliani, P., Di Marco, F., Braido, F., Corsico, A. G., Amici, C. A, and Santus, P. (2019). Satisfaction with chronic obstructive pulmonary disease treatment: results from a multicenter, observational study. Therapeutic advances in respiratory disease, 13, 1,753,466,619,888,128.	Contoli, M., Rogliani, P., Di Marco, F., Braido, F., Corsico, A. G., Amici, C. A., and Santus, P.	2019	Therapeutic advances in respiratory disease	Scopus	Adherence, COPD, treatment satisfaction	Italy (UE)	The main exclusion criteria included patients naïve/without chronic, inhaled treatment, concomitant diagnosis of asthma.	401, 299 males (74.6%), 71.7±7.6	1) The primary endpoint was to describe patients’ satisfaction with COPD medical treatments by means of the TSQM-9 during a 12-month observation period in a real-world setting 2) The secondary endpoints included: (a) disease perception, adherence to treatment, health status, and dyspnea over the 12-month observation period; and (b) identification of factors associated with patient satisfaction with COPD medical treatments.	1) satisfaction with MT; 2) illness perception; 3) adherence to treatment; 4) health status; dyspnea 5) adherence	Multicenter, noninterventional (observational) cohort study	A significant negative association (β = 0.4709, p < 0.0001) emerged between the scores to all items of the TSQM-9 questionnaire recorded at the end of the study and the disease perception (B-IPQ) score COPD patients with poor/suboptimal adherence to treatment (MMAS-4 scores 0–3) had a lower mean convenience score (about 6.6 points less; p < 0.0001) and lower global satisfaction score (of about 4.6 points; β = 4,5608, p < 0.002) compared with patients with optimal adherence (MMAS-4 score = 4). Moreover adherence and satisfaction were positively correlated.	Similar levels of TSQM-9 scores were found during the 12-month follow-up period between patients who changed (switchers, n=73) and who did not change (nonswitchers, n=231) their pharmacological inhalatory regimens	1) TSQM-9 2) B-IPQ 3) MMAS-4 4) CAT 5) mMRC questionnaire	correlation	x	The results of this real-life study showed that the patients’ satisfaction with treatments is only moderate in COPD. A high grade of patients’ satisfaction is associated mainly with a low perception of the disease, high adherence to treatment and lower level of dyspnea.
13	Heerema-Poelman, A., Stuive, I., and Wempe, J. B. (2013). Adherence to a maintenance exercise program 1 year after pulmonary rehabilitation: what are the predictors of dropout? Journal of cardiopulmonary rehabilitation and prevention, 33(6), 419–426.	Heerema-Poelman, A., Stuive, I., and Wempe, J. B.	2013	Journal of cardiopulmonary rehabilitation and prevention	PubMed	Adherence maintenance program pulmonary rehabilitation	Netherlands (UE)	Excluded were patients with progressive diseases interfering with short-term life expectancy, such as malignancies and unstable heart disease.	70, 32 males (45.7%), 61.3 (10.2)	1) To evaluate adherence to a maintenance exercise program in patients with chronic obstructive pulmonary disease (COPD) and explore predictors for adherence.	1) exercise capacity (walking test) 2) exercise self-efficacy; 3) illness perception; 4) health related quality of life; 5) anxiety and depression; 6) duration of pR; 7) Exacerbations; 8) Patient-reported reasons for nonadherence 9) Adherence to programme	Longitudinal Study	Health-related quality of life, anxiety, self-efficacy, exacerbations, and illness perceptions were found not to be predictive for adherence, probably due in part to shared variance with other variables, for example, FEV 1.	The most frequently patient-reported reason for dropout was exacerbations. The logistic model showed that especially (1) worse disease (lower FEV 1), (2) more depressive symptoms, and (3) shorter duration of the rehabilitation program predicted dropout from our maintenance exercise program	1) shuttle walking test; 2) exercise self-regulatory efficacy scale; 3) IPQ 4) HRQL questionnaire 5)HADS 6) n of exacerbation 7) self report questionnaire 8) drop out	Logistic regression analysis	22	Adherence to a maintenance exercise program, after PR, is quite reasonable for patients with COPD. Nonetheless, about one-third of patients dropped out during the first year. Experiencing exacerbations was the most reported reason for dropout. Greater health impairments, that is, poorer lung function and more symptoms of depression, appeared to be predictive for dropout. Taking these factors into account may help in early identification of possible dropouts.
14	Fischer, M. J., Scharloo, M., Abbink, J. J., van‘t Hul, A. J., van Ranst, D., Rudolphus, A. and Kaptein, A. A. (2009). Drop-out and attendance in rehabilitation: the role of clinical and psychosocial variables. Respiratory medicine, 103(10), 1564–1571.	Fischer, M. J., Scharloo, M., Abbink, J. J., van‘t Hul, A. J., van Ranst, D., Rudolphus, A. and Kaptein, A. A.	2009	Respiratory medicine	PsycINFO	Attendance; Chronic obstructive pulmonary disease; Drop-out; Illness perceptions; Pulmonary rehabilitation	Netherlands (UE)	Patients who had already started rehabilitation or had primary lung conditions other than COPD were excluded from the study.	217, 122 males (56%), 63.4 (9.4)	1) The purpose of this prospective study is to investigate drop-out and attendance rates during rehabilitation programmes for patients with COPD and to provide an overview of reasons for drop-out and non-attendance. 2) A second aim of this study is to investigate whether patients’ illness perceptions add to the prediction of drop-out and non-attendance after controlling for sociodemographic and medical variables.	1) illness perception; 2) clinical parameters (BMI, FEV, BORG CR10, walking test); 3) medical Research Council (MRC) dyspnoea scale	Longitudinal Study	The present study showed that patients’ adherence to a pulmonary rehabilitation programme is high. More than 75% of the referred patients who participated in this study completed the rehabilitation course. The results of this study demonstrated a relationship between attendance during rehabilitation andpatients’ perceptions about the effectiveness of treatment. These perceptions are influenced by the patient-provider interaction, which suggest that communication between patient and healthcare provider may profit from an explora- tion and discussion of patients’ illness and treatment perceptions during the referral or intake phase. Although on average patients demonstrate high attendance, creating a positive yet realistic expectation of the rehabilitation appears to be an important objective if one aims to optimise patients’ adherence during rehabilitation.	Non-completion and non-attendance were often attributable to medical causes. Where the patient decided not to start or continue the rehabilitation programme, reasons were often practical (eg time constraints) or related to dissatisfaction with the organisation of care. Drop-out or decline was not related to medical and psychosocial variables. Patients’ attendance however, was related to their fat free mass and their perception of effectiveness of the treatment.	1) Drop out rehabilitation programme - attendance; 2) Illness perception;	Hierarchical logistic regres-sion analyses	50	In general, adherence in rehabilitation is high. However, paying attention to patients’ nutritional status and creating a positive expectation of treatment during referral and intake appear to be important if one aims to optimise patients’ attendance during rehabilitation.

Note: x means “not available”.

Table 4 List of Included Studies That Discussed Different Kinds of Adherence

Authors	Adherence Tool	Adherent vs Non-Adherent participants	Score
Agarwal, 2021^Citation36	MARS	134 vs 208	NA
Brandstetter, 2017^Citation38	MARS	70 vs 136	NA
Contoli, 2019^Citation40	MMAS-4	n.a.	3.4±0.9 (n=401) 95% CI 3.3–3.5
Duarte-de-Araùjo, 2018^Citation39	MTA	210 vs 90	NA
Fischer, 2009^Citation28	Drop-out numbers from pulmonary rehabilitation	80 vs 79	NA
Heerema- Poelman, 2013^Citation29	Maintenance program for 1 year after the pulmonary rehabilitation	38 vs 22	NA
Hom˛ Etowska, 2022^Citation35	ARMS	NA	21.15 ± 6.23–74%
	TAI	Sporadic non-compliance 74.15% Deliberate non-compliance 59.69% Unconscious non-compliance 11.38%	NA
Khdour, 2012^Citation14	MMAS	122 vs 51	NA
Huurne, 2018^Citation30	Patients’ pharmacy records	10 vs 10	This was expressed as a percentage and adherence was deemed good if it was 75%–125%, suboptimal between 50% and 75%, and poor below 50% (underuse) or above 125% (overuse)
Krauskopf, 2014^Citation37	MARS	79 vs 109	NA
López-Pintor, 2021^Citation12	TAI	143 vs 96	NA
Olszanecka-Glinianowicz, 2014^Citation34	MMAS-8	1600 vs 1002	Adherence: ≤4; Non-Adherence: ≥4
Pierobon, 2017^Citation33	MGL	70 vs 14	NA

Table 5 List of Included Studies That Discussed Different Kinds of Illness Beliefs and Cognition Tools

Authors	Beliefs-Cognitions Tool(s)	Score	Notes
Krauskopf et al, 2015^Citation37	BMQ	Necessity: 14.4±4 vs 14.1±4.7 p=0.54	Adherent vs Non-adherent
		Concerns: 11.4±3.2 vs 14.4±4.1 p<0.001
Brandstetter et al, 2017^Citation38	BM	Overuse: 3.2 (0.7)	Scores ranges from 1 to 5 for each scale, with higher values indicating stronger beliefs.
		Harm: 2.5 (0.7)
		Utility: 3.9 (0.7)
		Necessity: 2.6 (0.8)
		Concerns: 4.1 (0.7)
Duarte-de-Araújo et al, 2018^Citation39	BMQ	Necessity: 20.58±4.104 vs 15.75±5.777 p<0.001	Adherent vs Non-adherent
		Concerns: 10.76±4.265 vs 10.65±4.383 p=0.87
Agarwal et al, 2021^Citation36	BMQ	Necessity: 14 (10–18)
		Concerns: 12 (10–16)
Khdour et al, 2012^Citation15	Medication Effectiveness Belief questionnaire	Totally/mostly effective: 107 (63.7) Little/not effective: 61 (36.3)
López-Pintor et al, 2021^Citation12	Perception of ease of use of IT;	Easy: 307
		Difficult: 10
	Medication Effectiveness Belief questionnaire	Totally/mostly effective: 232 Little/not effective: 86
Hom ˛etowska et al, 2022^Citation35	BMQ	Overuse: 12.74 ± 3.18	Overuse: 4–20
		Harm: 11.29 ± 2.70	Harm: 4–20
		Necessity: 19.35 ± 2.97	Necessity: 5–25
		Concerns: 16.67 ± 3.25	Concerns: 5–25

Table 6 Relationship Between IP, Beliefs, and Cognitions and Adherence to Treatment in COPD Patients

Authors	Data Analysis Technique	Scores
Agarwal et al, 2021^Citation36	Chi squared test IPQ, BMQ - adherence	Those with low adherence had higher BIPQ scores [45 (39, 51) vs 42 (34, 50) p=0.001] and medication concern score [14 (10, 18) vs 11 (10, 14) p<0.001] as compared to those who were adherent
Brandstetter et al, 2017^Citation38	Logistic regression analyses of medication adherence on beliefs about medicines	Beliefs about the necessity of medicines were significantly associated with medication adherence (OR 2.46, CI 1.36–4.42), with stronger beliefs increasing the chance for adherence. Medication concern was not significantly associated with adherence.
Duarte-de-Araújo et al, 2018^Citation39	Chi squared test BMQ - adherence	Necessity: Adherent 20.58±4.104 vs non-adherent 15.75±5.777 p<0.001
		Concerns: Adherent 10.76±4.265 vs non-adherent 10.65±4.383 p=0.87
Fischer et al, 2009^Citation28	MANOVA	The poor and high attendance group differed in their illness perceptions (MANOVA F (8, 142) Z 2.47, p < 0.05). Treatment control was higher in the adherent group (16.3 vs 15.4 p=0.04).
Heerema-Poelman et al, 2013^Citation29	Descriptive statistics	IPQ-R personal control: adherent 20.7 (2.7) vs non-adherent 20.4 (4.4)
		IPQ-R treatment control: adherent 15.6 (2.2) vs non-adherent 16.2 (3.0)
Hom ˛etowska et al, 2022^Citation35	Correlation analysis between beliefs about medicines (BMQ) and treatment adherence (ARMS, TAI)	Belief that medicines are overused, harmful and concerns about medicines were significantly (p<0.05) and positively correlated with the total ARMS score. Therefore, the greater the belief that medicines are overused by doctors, the lower the level of adherence in all dimensions. Belief in the necessity of medication was significantly (p<0.05) and positively correlated with the lack of sporadic and unconscious non-compliance and was significantly and negatively correlated with the total ARMS score. Therefore, the stronger the belief in the necessity of medication, the higher the level of adherence in all dimensions. Belief that medicines are harmful and concerns about medicines were significantly (p<0.05) and negatively correlated with the lack of sporadic, deliberate and unconscious non-compliance. Therefore, the greater the concerns about medicines, the poorer the adherence to inhaled medications.
Khdour et al, 2012^Citation15	Student’s t-test	A significant association (p<0.01) was found between self-report of the effectiveness of medication and adherence behavior, ie those patients who felt that their medications were totally or mostly effective were more likely to report adherence to their medications.
Koehorst-ter Huurne et al, 2018^Citation30	Qualitative analysis – ATLAS.it	Most patients perceived their condition as stable, there was no difference between under- and over users in described symptoms or problems with everyday activities, in perceived causes or in perceived control. The majority of the non-adherent patients were not able to accept their disease and the accompanied treatment.
Krauskopf et al, 2015^Citation37	Unadjusted comparisons of beliefs according to self-reported adherence	Non-adherent participants reported being more concerned about their COPD (p=0.01; Cohen’s d=0.43). Non-adherent participants also had higher scores in the concerns subdomain of the BMQ, indicating increased worries about COPD medications (p<0.0001; Cohen’s d=0.81), adherent 11.4 (3.2) vs non-adherent 14.4 (4.1)
Lopez-Pintor et al, 2021^Citation12	Chi squared test	Patients who thought that inhaler’s effectiveness was good (145, 62.5% vs 41, 47.7%, p = 0.017) showed a good adherence rate.
Magdalena Olszanecka-Glinianowicz et al, 2014^Citation34	χ2 test	The mean total score of illness perception was significantly higher in adherence than non-adherence group. 55.4±10 vs 53.2±9.8 p<0.001
Pierobon et al, 2017^Citation33	Student’s t-test	No significant relations were found.

Table 7 Predictors of Adherence to Treatment in COPD Patients

Authors	Variable(s)	Tool(s)	Score
Agarwal et al, 2021^Citation36	Health Literacy	Short Test of Functional Health Literacy in Adults (S-TOFHLA)	β=−0.003, p=0.003
Brandstetter et al, 2017^Citation38	Depression;	HADS-D;	5.2 (4.1) vs 8.3 (4.6) p<0.01
	Disease severity;	COPD assessment test (CAT);	n.a.
	Health related quality of life	12-item Short Form Health Survey (SF-12);	Phy: 31.8 (9.7) p<0.01; Mental: 38.0 (14.3) p<0.01
	Self-efficacy	Generalized Self-Efficacy Scale (GSE)	28.2 (6.6) p<0.01
Contoli et al, 2019^Citation32	Treatment satisfaction	Treatment Satisfaction Questionnaire, 9 items (TSQM-9)	β=4,5608, p<0.002
Duarte-de-Araújo et al, 2018^Citation39	Smoking status		Odds ratio: 2.4–2.4 times more risk of non-adherence for current smokers
Fischer et al, 2009^Citation28	Body mass index (BMI)		p=0.04
Heerema-Poelman et al, 2013^Citation29	Forced Expiratory Volume in the 1st second (FEV1)		p=0.025
Hom ˛etowska et al, 2022^Citation35	Smoking status (non-smoker);		p=0.023
	Place of residence (rural area)		p=0.004
Khdour et al, 2012^Citation15	Co-morbid illness;		p<0.05
	Depression;	HADs-D	p<0.01
	Perceived barriers to taking medication	Health Belief Model (HBM) scale	p<0.05
	Knowledge of COPD		p<0.01
Krauskopf et al, 2015^Citation37	Education;		p=0.002
	Disease severity;	CAT	p=0.04
	Monthly income		p=0.02
Lopez-Pintor et al, 2021^Citation12	Physical activity;		p=0.035
	Smoking status;		p=0.049
	Knowledge of COPD;		p=0.003
	Receiving explanation about inhalers;		p=0.032
Pierobon et al, 2017^Citation33	BMI;		p<0.001
	Depression;	Beck Depression Inventory (BDI-II)	p<0.001

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