The possible synergistic effects of alcohol and tobacco
It has now been well established that tobacco and alcohol use is positively correlated. The reasoning behind the concurrent use of both substances is an area of much research because both substances have the potential for dependence, are associated with health risks, and the theory that both these substances serve as a gateway for the use of stronger illicit drugs. Moreover, both nicotine, the addictive substance in tobacco, and alcohol, like other psychoactive substances, cause pleasure production and positive reinforcement via the mesolimbic dopamine system in the brain. Current research has suggested a possible neurobiological synergy of alcohol and nicotine and potential simultaneous binding on a certain type of receptor, nicotinic acetylcholine receptors, that may be present in the mesolimbic system. In addition, the combined use of nicotine and alcohol may have psychological antecedents that include personality traits like impulsivity and sensation- seeking. Our study was designed to examine the relationship between alcohol and tobacco use through self-report measures. Participants from the spring 2007 UTExperience 21st birthday study were given a Tobacco Use Index Questionnaire (TUI). TUI questions asked about normal tobacco use, how often tobacco products and alcohol are used together, and how many standard drinks are consumed before initiation of tobacco use. In addition, subjective one to ten scales were used to see if feelings of intoxication changed when tobacco products were used while drinking, whether feelings of intoxication were more enjoyable when tobacco products were used, and whether tobacco use was more enjoyable when drinking alcohol. Along with the TUI data, previously collected information on participants’ values of sensation-seeking and impulsivity was analyzed to see if these values were associated with combined use. Individuals were classified based on normal tobacco usage into categories. It was found that among all participants higher impulsivity was associated with increased percentage of time tobacco products were used while drinking alcohol. In addition, there were differences in percentage of time that alcohol and 4 tobacco products are used concurrently based on typical tobacco use. It was also found that individuals who only used tobacco products while drinking reported needing a higher number of standard drinks to initiate tobacco use than other categories of tobacco users. Lastly, tobacco users, regardless of normal frequency of tobacco use, did not report high levels of feelings of intoxication, changes in enjoyment of feelings of intoxication, or changes in enjoyment of tobacco use when tobacco products and alcohol were used together. Due to the subjectivity of human based analysis, information from this study does not establish causality of neurobiological mechanisms, so more work done at the brain level needs to be done. Future areas of study include the characterization of the receptor types that bind both alcohol and nicotine in the brain as well as their location and effect on an individual’s behavior. Moreover, other factors, including the psychological personality variables of sensation-seeking and impulsivity, need to be studied and combined with biological data to truly understand the interaction of alcohol and nicotine.