Stronger alcohol-violence association when adolescents drink less? Evidence from three Nordic countries.

BACKGROUND Since 2000, adolescents' alcohol use and heavy episodic drinking (HED) have declined in the Nordic countries. However, little is known about corresponding trends in alcohol-related harm and possible changes in the alcohol-harm association. The aims are to examine (i) whether the decline in HED was accompanied by a decline in alcohol-related violence (AV) and (ii) whether the strength of the HED-AV association changed concomitant with the decline. METHODS Analysis of data from the European School Survey Project on Alcohol and Other Drugs (ESPAD), conducted among 15-16-year-olds in Iceland, Norway and Sweden in 2007 and 2015 (n = 17 027). Changes in proportions of AV and alcohol use past 12 months, and mean frequency of HED past 30 days were examined using Pearsons χ2-test and F-test, respectively. The HED-AV associations were estimated using logistic regression analysis. RESULTS HED and AV proportions decreased from 2007 to 2015 in all countries. Among current drinkers (n = 8927), both HED frequency and AV proportion decreased in Norway (P < 0.001) and remained stable in Iceland. In Sweden, AV decreased (P < 0.001) whereas HED remained stable. The magnitude of the HED-AV association increased in Norway (Beta2015-2007 = 0.145, 95% CI 0.054-0.236), remained the same in Iceland and decreased in Sweden (Beta2015-2007 = -0.082, 95% CI -0.158 to -0.005). CONCLUSIONS Among youth in Iceland, Norway and Sweden, heavy episodic drinking and alcohol-related violence declined from 2007 to 2015. Among drinkers, the strength of the alcohol-violence association was moderated by the extent of heavy episodic drinking.