Rationale: Alcohol-induced heart rate (HR) stimulation during the rising limb of the blood alcohol curve reliably discriminates between individuals at differential risk for alcoholism, and appears to be a potential psychophysiological index of psychomotor stimulation from alcohol.
Objectives: Three studies are presented which explore the reliability and convergent and discriminant validity of this alcohol response index.
Methods: Young men with and without a multigenerational family history of alcoholism were administered a 1.0 ml/kg dose of 95% USP alcohol. Resting baseline cardiac and subjective measures were assessed before and after alcohol consumption.
Results: Study 1 demonstrated that alcohol-induced HR stimulation was significantly and positively related to alcohol-induced changes in mood. Study 2 demonstrated that alcohol-induced HR stimulation was reliable across two alcohol administration sessions (r=0.33-0.66, P<0.01). Study 3 explored the relationship between the proposed index and measures of sensitivity to alcohol previously linked to genetic predisposition to alcoholism. Multiple regression analysis indicated that alcohol-induced HR increase and reduced subjective intoxication (measured using the Subjective High Assessment Scale) were both positively associated with alcohol-induced changes in mood states that have previously been shown to be sensitive to the effects of stimulant drugs and the reinforcing effects of alcohol.
Conclusions: Sensitivity to alcohol-induced heart-rate stimulation during the ascending limb of the blood alcohol curve may be a useful and informative marker for understanding susceptibility to alcoholism.