Drinking motives as mediators between PTSD symptom severity and alcohol consumption in persons with severe mental illnesses.

Research has consistently shown that drinking to alleviate negative emotional states predicts alcohol use and relapse among clients with co-occurring disorders including depressive and posttraumatic stress disorders. However, studies examining the mediating role of drinking motives in persons with severe mental illness (SMI) are few. The current survey of 116 community mental health clients (51.7% men; 47.4% women) diagnosed with either a schizophrenia spectrum disorder (41, 35.3%) or major mood disorder (75, 64.7%) tested the hypothesis that convivial drinking and drinking to cope with negative emotions would mediate posttraumatic stress symptoms (PSS-I) and alcohol consumption (QF). A series of path models revealed that convivial drinking fully mediated hyper-arousal symptoms and alcohol consumption, and negative coping fully mediated total posttraumatic stress symptoms, avoidance and hyper-arousal symptoms and alcohol consumption. The results support an emotional distress reduction model of alcohol use in people with severe mental illness, and highlight the need to assess specific drinking motives and target them in cognitive-behavioral treatment approaches. The cross sectional design employed limits cause-effect inferences regarding mediation, and highlights the need for longitudinal designs to sort out causal pathways among symptoms, drinking motives and alcohol consumption in clients with SMI.