Smoking and the consumption of antidepressants, anxiolytics and hypnotic drugs: results of a large, French epidemiological study in 2005.

The aim of this study was to describe and analyse the links between the consumption of psychotropic drugs and smoking, based on data from individuals subscribing to a health insurance organisation (a mutuelle) in France in 2005. Data on smoking status, depression, anxiety and alcohol consumption from a large transversal epidemiological study carried out in 2005 were analysed in parallel to individual data concerning the reimbursement of medical prescriptions for psychotropic drugs. We compared reimbursement data for psychotropic drugs between individuals who had smoked for at least 15 years and continued to smoke and individuals who had stopped smoking after at least 15 years of smoking. This group of ex-smokers was subdivided into three subgroups on the basis of the number of years elapsed since the time point at which the individual had been smoking for 15 years: 1 to 9 years, 10 to 19 years and 20 years or more. "Ex-smoker" status was associated with a lower risk of psychotropic drug prescription than "current smoker" status (OR=0.81 for anxiolytics, OR=0.74 for antidepressants). Analysis of the subgroups of smokers and ex-smokers also showed that mean annual consumption of antidepressants and anxiolytics was significantly lower for individuals who had stopped smoking after at least 15 years of the habit than for those who continued to smoke (respectively 1.34 versus 0.65 for anxiolytics, and 1.17 versus 0.62 for antidepressants). Our findings suggest that stopping smoking is associated with a decrease in the consumption of psychotropic drugs. They highlight the need to evaluate the medium- and long-term effects of stopping smoking on psychotropic drug consumption in more detail, taking into account the anxious and depressive disorders to which smokers are particularly prone.