2007 HSR&D National Meeting Abstract
3095 — Substance Use Disorders Interact with Depressive Symptoms to Predict Depressive Outcomes
Tiet QQ (VAPAHCS/Stanford University) , Schutte K
Research has documented unfavorable outcomes in dual diagnosis patients. However, no study has empirically examined the interaction effects between a substance use disorder and baseline depressive symptoms on depressive outcomes, and separately for male and female patients. This study tested this hypothesis in VA mental health patients.
The current analyses utilized baseline and 6-month follow-up (N=345) data on patients entering treatment at one of four specialty psychiatric or SUD clinics in California and Maryland. Participants completed the computerized Diagnostic Interview Schedule (C-DIS) at treatment initiation and a patient self-report survey at baseline and at 6-month follow-up, including a depressive symptom scale, and other patient psychiatric and substance use measures. Three-way interactions among gender (male/female), substance use disorders (Y/N: separately for alcohol versus drug disorders), and baseline depressive symptoms were examined. To de-compose the 3-way analyses, analyses were conducted separately for male and female patients to examine the interaction effects between SUD (alcohol or drug disorders) and baseline depressive symptoms on 6-month follow-up depressive outcomes.
Three-way interactions among gender, baseline depressive symptoms, and alcohol diagnosis (p=.015) or drug diagnosis (p=.043) were statistically significant. When male and female data were analyzed separately, depressive symptoms at follow-up were predicted by an interaction effect between an alcohol diagnosis and depressive symptoms at baseline (p=.009) for male patients (p=.065 for female patients), and significantly predicted by an interaction effect between having a drug use disorder and baseline depressive symptoms in women (p=.003), but not in men.
Baseline SUD and depressive symptoms had different effects on male and female patients’ depressive outcomes. Female patients with a drug disorder and male patients with an alcohol disorder, on average, had worse depressive outcomes than those who did not. Current findings warrant replication. If replicated, future studies should address systemic factors that differentially affect depressive outcomes in male and female dual diagnosis patients in the VA.
Clinicians need to routinely assess substance use problems in psychiatric patients because dually diagnosed patients may have worse psychiatric outcomes if not adequately addressed.