Ethanol-induced autonomic responses and risk taking increase in young adults with a positive family history of alcohol problems.

The mechanisms that underlie the greater prevalence of alcohol use disorders in individuals with a positive family history (FH+) of alcohol abuse are still under investigation. These subjects may exhibit differential sensitivity to alcohol's effects on psychomotor stimulation and impulsivity. Alcohol-induced psychomotor stimulation, measured as the heart rate (HR) response, is a proxy for the positive rewarding effects of the drug. We analyzed alcohol-induced effects on time perception (Time Production Task), risk taking (Balloon Analogue Risk Task [BART]), and HR in FH+ and FH- participants. In the FH+ and FH- groups, women and men received 0.6 and 0.7g/kg alcohol, respectively. The alcohol dose yielded a breath alcohol concentration of 0.08% throughout the experiment. The control groups received placebo, and the subjective perception of alcohol intoxication was assessed. Alcohol intoxication significantly increased HR and the adjusted average number of pumps on the BART (a measure of risk taking) in FH+ men and women but not in FH- participants. Behavioral impulsivity was unaffected by alcohol or a FH of alcohol abuse. FH- but not FH+ participants who received alcohol reported significantly greater subjective perception of alcohol's effects than their placebo counterparts. These results indicate that FH+ individuals presented heightened sensitivity to alcohol-induced HR stimulation and alcohol-induced risk taking compared with their FH- counterparts. FH+ subjects, however, were insensitive to the subjective effects of alcohol. This idiosyncratic response pattern may be a likely pathway by which a FH of alcohol problems promotes alcohol drinking.