Smoking behaviour and mental health disorders--mutual influences and implications for therapy.

Tobacco use is strongly associated with a variety of psychiatric disorders. Smokers are more likely than non-smokers to meet current criteria for mental health conditions, such as mood disorders, anxiety disorders and psychosis. Evidence also suggest that smokers with psychiatric disorders may have more difficulty quitting, offering at least a partial explanation for why smoking rates are higher in this population. The mechanisms linking mental health conditions and cigarette smoking are complex and likely differ across each of the various disorders. The most commonly held view is that patients with mental health conditions smoke in an effort to regulate the symptoms associated with their disorder. However some recent evidence suggests that quitting smoking may actually improve mental health symptoms. This is particularly true if the tobacco cessation intervention is integrated into the context of ongoing mental health treatment. In this paper we reviewed and summarized the most relevant knowledge about the relationship between tobacco use and dependence and psychiatric disorders. We also reviewed the most effective smoking cessation strategies available for patients with psychiatric comorbidity and the impact of smoking behavior on psychiatric medication.