Nicotine-enhancement of sweetened alcohol consumption: A behavioral economic evaluation

RPL Scott Barrett- "Nicotine-enhancement of sweetened alcohol consumption: A behavioral economic evaluation": Tobacco use is one of the greatest public health threats and largest contributors to the global burden of preventable death and disease, resulting in over 8 million global tobacco-related deaths annually. Nicotine is the primary addictive constituent of tobacco. Research demonstrates that nicotine produces reinforcer value-enhancing effects which may contribute to tobacco use above and beyond the primary reinforcing effects of nicotine. Although smoking rates have generally decreased over the past few decades, smoking rates among persons with alcohol use disorder (AUD) remain as high as 50 to 80%. Persons with AUD who smoke also exhibit greater alcohol consumption than nonsmoking persons with AUD. Alcohol is commonly consumed in mixed solution with other appetitive reinforcers— frequently sugar carbohydrates or noncaloric sweeteners that increase the palatability of alcohol. Sweetening alcohol leads to higher rates of alcohol consumption and intoxication and a growing body of research indicates the consuming alcohol mixed with noncaloric sweeteners results in even greater intoxication due to faster gastric emptying. For all these reasons, a comprehensive understanding of tobacco use, heavy alcohol use, and the comorbidity between nicotine and alcohol dependence must consider the value-enhancing effects of nicotine in conjunction with the various nonalcoholic sensory and appetitive reinforcers that commonly accompany alcohol consumption. Our long-term objective is to elucidate how the value-enhancing effects of nicotine may contribute to increased alcohol consumption and heightened risk of AUD in tobacco users, and thereby inform treatment strategies aimed at smoking cessation and curtailing problematic drinking. To that end, the proposed research will employ a behavioral economic demand methodology to characterize and compare the value-enhancing effects of nicotine on a range of caloric and noncaloric appetitive reinforcers, with or without alcohol, in male and female rats. An advantage of the reinforcer demand methodology is that it measures reinforcement value along multiple dimensions of behavior and thereby provides a rich characterization of differences in the motivational strength of a reinforcer under varying conditions. Aim 1 will comparatively evaluate the reinforcement value of sucrose, stevia, and sucralose—caloric and noncaloric sweeteners commonly found in mixed alcoholic beverages—as well as the value-enhancing effects of nicotine on each. Aim 2 will examine the effects of each sweetener on demand for alcohol and the effects of nicotine on alcohol consumption, with or without each sweetener. Though the proposed research is focused on nicotine and alcohol dependence, the methods and findings of this research may extend further in scope to drug addiction and polysubstance use generally, as well as provide a foundation for other basic and clinical scientists to develop more effective treatment strategies.