Anxiety and substance use comorbidity among inpatients with schizophrenia

OBJECTIVE: To determine the association between lifetime anxiety symptoms and anxiety disorders and substance use disorders among patients with schizophrenia. METHOD: Participants were 184 inpatients with schizophrenia at the Schizophrenia Research Unit (SRU) at the New York State Psychiatric Institute (NYSPI). Multivariate logistic regression analyses were used to determine the relationship between specific anxiety symptoms and anxiety disorders and substance use disorders among inpatients with schizophrenia. RESULTS: Anxiety symptoms and anxiety disorders were prevalent among 31.5% of the sample. Panic attacks were associated with a significantly increased odds (OR=7.4 (1.2, 47.1)) of comorbid alcohol or substance use disorders (lifetime). This association was specific to panic attacks and persisted after adjusting for differences in sociodemographic characteristics and comorbid anxiety symptoms and anxiety disorders. CONCLUSIONS: These findings are consistent with and extend previous data by providing evidence of an association between panic attacks and increased likelihood of substance use disorders among inpatients with schizophrenia. Future studies that determine the nature of this relationship, the sequence of symptom onsets, and examine whether treatment of anxiety can influence the onset or outcome associated with substance use are needed.