At the time of the baseline interview, 982/3286 subjects had an externalizing diagnosis (29.9%); 140/3286 subjects had an internalizing diagnosis (4.3%), 286 had both (8.7%) and 1878 had neither (57.2%) (Table 1). All covariates (sex, ethnicity, family type) had significant relationships to age of onset in subjects with either mild, moderate, or severe AUD (Table 2). The association of any comorbid disorder and presence of Alcohol Use Disorder was significant overall (chi-square p-value < 0.0001), and there was a significant effect of comorbidity on age of onset as well (p < 0.001 for each type of AUD, Figure 1a–c). Among subjects with an externalizing disorder only at baseline, 515/982 (52.4%) had some type of AUD during the follow-up period. Among subjects with an internalizing disorder only at baseline 66/140 (47.1%) had an AUD. Among subjects with both externalizing and internalizing, 182/286(63.6%) had an AUD. In comparison, subjects with neither type of disorder had an AUD rate of 34.7% (653/1878).
