How does young people's alcohol consumption change during the transition to early adulthood? A longitudinal study of changes at aggregate and individual level.

We have analysed data from a longitudinal representative study to explore aggregate and individual level changes in alcohol use from late adolescence to early adulthood. The sample, which consisted of 2000 Norwegians, was assessed at ages 19-22, 21-24 and 25-28 years. Only a bare majority of the respondents reduced their alcohol intake during the course of the study, whereas a substantial proportion showed an increase. The initial drinking level in individuals whose consumption declined was quite high, and the opposite was true for those who increased their consumption. The findings seemed to reflect true changes, implying that they only could be attributed to measurement errors to a limited extent. The stability in absolute alcohol intake was rather low, especially at the very high consumption levels. However, the respondents clearly tended to maintain their relative drinking position over time. Furthermore, the very high consumers were actually somewhat more apt than others to hold their position relative to the group. In contrast to previous research, these results thus suggest that there is a substantial stability in alcohol use over time. This in turn underscores the importance of implementing preventive programmes targeted towards factors that promote heavy drinking in adolescents.