Heterogeneity in the Co-occurrence of Substance Use and Posttraumatic Stress Disorder: A Latent Class Analysis Approach

Abstract

Objective: Posttraumatic stress disorder (PTSD) often co-occurs with substance use (SU). Although there has been independent research on subgroups of participants based on their PTSD or SU responses, rarely are PTSD-SU typologies examined consistent with a precision medicine approach (and corresponding person-centered statistical approaches). The current study examined the nature and construct validity (covariates of depression, physical aggression, verbal aggression, anger, hostility, reckless and self-destructive behaviors [RSDB]) of the best-fitting latent class solution in categorizing participants based on PTSD (PTSD Checklist for DSM-5) and alcohol/drug use responses (Alcohol Use and Disorders Identification Test Alcohol Consumption Questions, Drug Abuse Screening Test). Methods: The sample included 375 trauma-exposed participants recruited from Amazon’s Mechanical Turk online labor market. Results: Latent class analyses indicated an optimal three-class solution (low PTSD/SU, moderate PTSD/drug and high alcohol, and high PTSD/SU). Multinomial logistic regressions indicated that depression (OR = 1.22) and frequency of RSDBs (OR = 1.20) were significant predictors of the moderate PTSD/drug and high alcohol class versus the low PTSD/SU class. Depression (OR = 1.55) and frequency of RSDBs (OR = 1.19) were significant predictors of the high PTSD/SU class versus the low PTSD/SU class. Only depression (OR = 1.27) was a significant predictor of the high PTSD/SU class versus the moderate PTSD/drug and high alcohol class. Conclusions: Results provide construct validity support for three meaningful latent classes with unique relations with depression and RSDBs. These findings improve our understanding of heterogeneous PTSD-SU comorbidity patterns and highlight acknowledgment of such subtyping (subgrouping) in considering differential treatment options, treatment effectiveness, and resource allocation.

Keywords:

• PTSD
• alcohol use
• drug use
• latent class analyses
• depression
• reckless behaviors
• aggression

Acknowledgements

We thank Ms. Jackeline Marquez and Ms. Sara Koh for reviewing the literature on trauma, PTSD, and risky behaviors to aid in the development of PRBQ’s domains/subdomains and their items. We thank Drs. Jon D. Elhai, Tami P. Sullivan, Matthew T. Tull, Lily A. Brown, and Melanie S. Harned for their expert feedback on domains/subdomains and their items in the expert review panel stages of scale development.

Disclosures

Drs. Contractor, Weiss, and Blumenthal report no financial relationships with commercial interests. Dr. Dixon-Gordon receives compensation for professional services from the American Psychological Association and Behavioral Tech LLC.

Additional information

Funding

 The research described here was supported, in part, by grants from the National Institute on Drug Abuse [K23DA039327; L30DA038349] awarded to the second author. The research described here was supported, in part, by grants from the National Institute on Alcohol Abuse and Alcoholism [R15 AA026079-01] awarded to the last author.