Psychosis and smoking cessation: difficulties in quitting associated with sex and substance abuse.

No prospective studies of first psychotic episodes have explored sex differences in smoking cessation. The aim of this study was to determine the influence of sex and substance abuse on smoking cessation during an 8-year follow-up of patients after a first psychotic episode. Logistic regression modeling was used to identify factors associated with smoking cessation by sex. To examine for sex variable interactions, the following two methods were used: 1) for other clinical variables, mixed analyses were calculated; and 2) for use of other substances, logistic regression models were performed only in the substance users. At baseline, 79% of men and 84% of women were current smokers. Lower smoking cessation after 8 years was associated with female sex (odds ratio, OR=0.30; 95% confidence intervals, CIs=0.12-0.75) and treatment with typical antipsychotics (OR=0.30, CIs=0.10-0.93). In a logistic regression model of alcohol users, those who used alcohol continuously were less likely to stop smoking (adjusted OR=0.22, CI=0.05-1.0). Among patients who continued using cannabis, female sex was associated with significant lower smoking cessation (adjusted OR=0.03, CI=0.001-0.77). Sex may act as a moderator in smoking cessation after a first psychotic episode. Smoking cessation interventions in these patients should consider sex differences and comorbidity with alcohol and cannabis use.