Smoking prevalence and correlates among inpatients with schizophrenia or schizoaffective disorder

Many studies have shown that cigarette smoking prevalence rate is high in patients with schizophrenia. Despite the strong association between smoking and schizophrenia, findings on the relationships between smoking, psychiatric symptoms and cognitive functions remain mixed. Furthermore, the smoking rate among acute inpatients who need tertiary mental health care is still unknown. In this study we investigated the smoking rate in this patient population and examined connections between smoking and cognitive functions, psychiatric symptoms, and clinical and demographic characteristics. A retrospective chart review of patients admitted to a tertiary acute psychiatric facility over a 7-year period was conducted. Information such as patient smoking status, diagnosis, and psychiatric assessment scores, were retrieved. Independent samples t-tests and Chi-squared tests were used to compare variables between smoker and non-smoker groups. The smoking prevalence rate was 72%, approximately four times the smoking rate in the general population in Canada. Compared to the non-smoker group, the smoker group were significantly younger, more likely to be male, had less years of education, shorter illness duration, higher rate of concurrent substance use disorder, and less days of hospital stay. However, the two groups did not show differences in severity of illness, types/numbers of medication used, positive and negative symptoms, and cognitive impairment. Smoking status appeared to be associated with several demographic and clinical features. Smoking did not significantly relate to patients' illness severity, medication use, psychiatric symptoms, or cognitive functioning.