Grant: CIHR Fellowship

The majority of alcohol dependent individuals are also daily cigarette smokers, and smoking increases risk for tobacco-related disease and alcohol relapse. To improve patient outcomes, it is critical to incorporate smoking cessation interventions into outpatient alcohol dependence treatment. An effective cessation aid in the general population is nicotine replacement therapy (NRT), like the nicotine patch. Care must be taken to determine which alcohol dependent individuals would benefit from NRT. The effect of NRT on alcohol use likely differs for heavy drinkers because nicotine and alcohol are known to interact pharmacologically, through shared metabolic pathways, and psychologically, by influencing craving for and desirable effects of each substance when used together. The proposed research will examine how one's rate of nicotine metabolism, assessed by a biomarker called nicotine metabolic ratio (NMR), impacts the relation between NRT on alcohol relapse risk among heavy drinking daily smokers. Furthermore, the mechanisms by which NRT impacts alcohol administration will be explored, by examining if NRT primarily impacts alcohol relapse risk by reducing nicotine withdrawal or through direct pharmacological action on alcohol use, craving or reward. This is only the second study to evaluate the effect of NRT on alcohol relapse risk among heavy drinkers, and the first study to investigate the role of genetic differences in nicotine metabolism and nicotine and alcohol psychopharmacological interactions in explaining the effects of NRT on alcohol. If our hypothesis is supported, we will demonstrate that NRT can be safely used in a subset of heavy drinkers to reduce their smoking, particularly individuals who metabolize nicotine slowly and are actively reducing their smoking. These findings could have important implications for how smoking is treated among alcohol dependent individuals in outpatient settings.