Sixty-five percent of ever-drinkers had an alcohol problem, which occurred at a mean age of 17.5 (sd 2.56), with an average of 2.4 years elapsing from first drink to first problem. Maternal AUD, regardless of paternal AUD status, increased the hazard of transitioning from alcohol use to an AUD problem by 27%, but paternal AUD in the absence of maternal AUD did not. (Table 3). A violation of the proportional hazards assumption was observed, where the likelihood of transitioning to having an alcohol problem in the first year after starting to drink was increased by 39% among those with externalizing disorders, but not thereafter. Ever-use of cannabis, internalizing disorders in females only, and peer substance use were associated with 111%, 40% and 56% (respectively) increased hazards of transitioning to an alcohol problem, and these did not vary across the risk period. Those who experienced parental separation were significantly less likely to transition to having an alcohol problem. Neither nonassaultive nor assaultive trauma was significantly related to the transition to having an alcohol problem.
