These findings confirm our prior report of an association between longitudinal AUDIT-C scores recorded in the VA EHR and a protective ADH1B variant in AAs (rs2066702) (8), and we extended this work in several ways. First, we demonstrated that longitudinal AUDIT-C metrics are also associated with a protective ADH1B variant in EAs (rs1229984). Second, in both populations, we showed that a computationally simpler longitudinal metric—age-adjusted mean AUDIT-C score—is more strongly associated with the ADH1B variants than AUDIT-C trajectories. This finding is likely due to the fact that drinking patterns are well established by middle age (23, 24). Nonetheless, adjusting the mean AUDIT-C score for age is important, because drinking decreases after middle age (25). In contrast, trajectories would likely perform better than age-adjusted means for behaviors that change non-linearly over time. Finally, by design, AUDIT-C metrics and AUD diagnostic codes measure different aspects of harmful alcohol use. AUDIT-C is a screening tool that uses a past-year timeframe while AUD diagnostic codes reflect established lifetime diagnoses. Although longitudinal AUDIT-C scores showed more protective associations with ADH1B variants, AUD codes added independent information.
