The role of hazardous drinking reductions in predicting depression and anxiety symptom improvement among psychiatry patients: A longitudinal study

Background: Co-occurrence of depression, anxiety, and hazardous drinking is high in clinical samples. Hazardous drinking can worsen depression and anxiety symptoms (and vice versa), yet less is known about whether reductions in hazardous drinking improve symptom outcomes. Methods: Three hundred and seven psychiatry outpatients were interviewed (baseline, 3-, 6-months) for hazardous drinking (drinking over recommended daily limits), depression (PHQ-9), and anxiety (GAD-7) as part of a hazardous drinking intervention trial. Longitudinal growth models tested associations between hazardous drinking and symptoms (and reciprocal effects between symptoms and hazardous drinking), adjusting for treatment effects. Results: At baseline, participants had moderate anxiety (M=10.81; SD=10.82) and depressive symptoms (M=13.91; SD=5.58); 60.0% consumed alcohol at hazardous drinking levels. Over 6-months, participants' anxiety (B=-3.03, p < .001) and depressive symptoms (B=-5.39, p < .001) improved. Continued hazardous drinking led to slower anxiety (B=0.09, p=.005) and depressive symptom (B=0.10, p=.004) improvement; reductions in hazardous drinking led to faster anxiety (B=-0.09, p=.010) and depressive (B=-0.10, p=.015) symptom improvement. Neither anxiety (B=0.07, p=.066) nor depressive (B=0.05, p=.071) symptoms were associated with hazardous drinking outcomes. Limitations: Participants were psychiatry outpatients, limiting generalizability. Conclusions: Reducing hazardous drinking can improve depression and anxiety symptoms but continued hazardous use slows recovery for psychiatry patients. Hazardous drinking-focused interventions may be helpful in promoting symptom improvement in clinical populations. (C) 2016 Elsevier B.V. All rights reserved.