Cigarette smoking and psychotic symptoms in bipolar affective disorder

Background An association exists between smoking and schizophrenia, indepen dent of other factors and related to psychotic symptomatology. Aims To determine whether smoking is associated with psychosis in bipolar a ffective disorder. Method Smoking data were collected from 92 unrelated patients with bipolar affective disorder. An ordinal logistic regression analysis tested the rela tionship between smoking severity and psychotic symptomatology, allowing fo r potential confounders. Results A significant relationship was detected between smoking/heavy smoki ng and history of psychosis (68.7%, n=44). Smoking was less prevalent in pa tients who were less symptomatic (56.5%, n=13)than in patients with a more severe psychosis (75.7%, n=31). Prevalence and severity of smoking predicte d severity of psychotic symptoms (P=0.001), a relationship independent of o ther variables (P=0.0272). Conclusion A link between smoking and psychosis exists in bipolar affective disorder and may be independent of categorical diagnosis.