Predictors of smoking severity in patients with schizophrenia and alcohol use disorders.

The goal of the present study was to identify predictors of smoking severity in patients with schizophrenia and co-occurring alcohol use disorders (AUD). Our hypothesis was that negative symptoms of schizophrenia, severity of depression, male gender, drinking severity, and recreational drug use were associated with increased smoking. Clinical data, including demographic variables, alcohol and substance use severity, psychiatric medications, severity of depression, positive and negative symptoms of schizophrenia were analyzed in a cohort of 90 patients with schizophrenia or schizoaffective disorder and AUD. Eighty-eight percent of participants were smokers, they smoked an average of 15 cigarettes/day. Zero-inflated negative binomial (ZINB) regression analyses demonstrated that alcohol use severity, gender, and severity of negative symptoms were not predictive of the number of cigarettes smoked. Smoking severity was positively related to Caucasian race, psychosis severity (Positive and Negative Syndrome Scale [PANSS] general score), and medications (conventional antipsychotics). Subjects who used recreational drugs smoked less. In summary, severe, treatment resistant schizophrenia, and conventional antipsychotic treatment is associated with heavy smoking in patients with schizophrenia and AUD regardless of gender or alcohol use.