Historical variation in young adult binge drinking trajectories and its link to historical variation in social roles and minimum legal drinking age

This study examines historical variation in age 18 to 26 binge drinking trajectories, focusing on differences in both levels of use and rates of change (growth) across cohorts of young adults over 3 decades. As part of the national Monitoring the Future Study, over 64,000 youths from the high school classes of 1976 to 2004 were surveyed at biennial intervals between ages 18 and 26. We found that, relative to past cohorts, recent cohorts both enter the 18 to 26 age band engaging in lower levels and exit the 18 to 26 age band engaging in higher levels of binge drinking. The reason for this reversal is that, relative to past cohorts, binge drinking among recent cohorts accelerates more quickly across ages 18 to 22 and decelerates more slowly across ages 22 to 26. Moreover, we found that historical increases in minimum legal drinking age account for a portion of the historical decline in age 18 level, whereas historical variation in social role acquisition (e.g., marriage, parenthood, and employment) accounts for a portion of the historical acceleration in age 18 to 22 growth. We also found that historical variation in the age 18 to 22 and age 22 to 26 growth rates was strongly and positively connected, suggesting common mechanism(s) underlie historical variation of both growth rates. Findings were generally consistent across gender and indicate that historical time is an important source of individual differences in young adult binge drinking trajectories. Beyond binge drinking, historical time may also inform the developmental course of other young adult risk behaviors, highlighting the interplay of epidemiology and etiology.