Is risk-taking propensity a familial vulnerability factor for alcohol use? An examination in two independent samples.

Research indicates that increased risk-taking propensity (RTP) is associated with higher alcohol use. There is also some evidence to suggest that it is not just a state factor or 'scar,' but instead a vulnerability factor. If this is the case, increased RTP should be evident in healthy individuals that are at risk for alcohol use. To date, few studies have examined whether RTP is a familial vulnerability factor and thus, the aim of the current study was to test whether RTP aggregates within families and if increased RTP is evident in biological family members at risk for alcohol use. Sample 1 included 87 biological, adult sibling pairs and Sample 2 included 111 biological mother and adolescent dyads (total N = 396). All participants completed a behavioral measure of RTP and were assessed for alcohol use. Results in both samples were strikingly consistent. In Sample 1, RTP was correlated among siblings and greater frequency of proband alcohol use predicted greater sibling RTP, over and above sibling alcohol use. In Sample 2, RTP was correlated among mothers and their offspring and greater maternal alcohol use problems predicted greater adolescent RTP over and above adolescent substance use. Together, these findings suggest that RTP may be a familial vulnerability factor for alcohol use as it aggregates within families and is increased in relatives of individuals with higher levels of alcohol use.