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

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.