Effects of Cigarette Smoking and Clozapine Treatment on 20-Year All-Cause & Cardiovascular Mortality in Schizophrenia

To estimate 20-year mortality risk in people with schizophrenia treated with second-generation antipsychotics (SGA) and examine the effects of cigarette smoking on mortality. Of the 1199 individuals with schizophrenia in the study, estimated 20-year all-cause mortality risk by Kaplan Meier Curve was 30% and leading causes of death included 27% cardiovascular disease, 13% cancer, 12% non-HIV infection, 5% respiratory causes, 20% other causes and 18% had unknown cause of death. For all-cause mortality, we found that white race and male sex were significant risk factors (HR=1.5, p=0.002 and HR=1.33, p=0.033, respectively). For cardiovascular mortality risk, we showed that cigarette smokers and white race were at higher risk (HR=1.86, p=0.017 and HR=1.71, p=0.045, respectively). Cardiovascular mortality risk at 20-years is 11%. Kaplan-Meier Survival Curve showed a statistical difference for smokers and non-smokers in cardiovascular mortality over the 20-year follow-up (Log rank chi-square=5.35, df=1, p=0.02). 20-year all-cause mortality risk for individuals with schizophrenia was found to be 30% with cardiovascular disease as a leading cause. Cigarette smokers and white race were associated with an increased risk of death. Regarding cardiovascular mortality specifically, cigarette smoking increased risk by 86% over a 20-year period. Clozapine was neither a risk factor for all-neither cause nor cardiovascular mortality. This data suggests that long-term cardiovascular mortality continues to be increased in schizophrenia for those who are or have been cigarette smokers.