Exposure to adverse events in childhood, such as physical abuse, sexual abuse, neglect, and witnessing violence, has consistently been linked to an elevated risk of developing an AUD in adulthood (Afifi et al., 2012, Fergusson et al., 1996a, Kendler et al., 2000, Kessler et al., 1997a, Nelson et al., 2006, Schilling et al., 2007). Childhood adversity is among the most commonly studied environmental risk factors in gene by environment (GxE) studies of alcohol phenotypes. Stressful life events, defined more broadly and including primarily events in adulthood, have been studied as environmental modifiers of genetic liability to AUD as well (Bau et al., 2000, Dick et al., 2007, Madrid et al., 2001). However, we consider exposure to adverse childhood events to be a more informative environmental risk factor both because of the consistency of the literature on its association with alcohol outcomes and because, by definition, it precedes the period of peak risk for the initiation of alcohol use, that is adolescence. This allows for the interpretation that adverse events are contributors to – rather than consequences of – heavy or problem alcohol use.
