Mortality and morbidity at legal drinking age thresholds: Evidence from a nationwide quasi-experimental study in...

To examine the effect of the minimum legal drinking age (MLDA) on mortality and hospitalizations.

Exploiting sharp increases in legal alcohol access at ages 18 years (beer/wine, on-premises drinking and car driving) and 20 years (off-premises spirits) in a regression discontinuity (RD) design, we estimated local linear models of all-cause and cause-specific mortality and hospitalizations in monthly data 12 months before and after each threshold, separately by sex.

Finland.

Individuals born between 1955 and 1998 who were registered as living in Finland and observed reaching ages 18 years and 20 years in the administrative registers (n ≈ 3 000 000).

The outcomes were all-cause and cause-specific mortality and hospitalizations due to external, alcohol-related, traffic-accident and suicide-attempt causes, measured as monthly rates per 100 000 person-months.

Reaching the legal drinking threshold of 18 years old was associated with a substantial increase in all-cause mortality among men [RD estimate = 1.62 deaths per 100 000 person-months, 95% confidence interval (CI) = 0.86-2.38], corresponding to a 26.9% increase relative to the pre-threshold mean. This effect was driven by external causes (RD = 2.03, 95% CI = 1.25-2.82) and particularly accidental deaths (RD = 1.49, 95% CI = 0.79-2.18) and alcohol-contributed deaths (RD = 0.65, 95% CI = 0.13-1.18). Among women, the increase in all-cause mortality at age 18 years was smaller and not statistically significant (RD = 0.45, 95% CI = -0.02 to 0.92), although alcohol-contributed deaths increased from a low baseline (RD = 0.18, 95% CI = -0.02 to 0.39). At age 20 years, legal access to spirits was associated with increases in alcohol-contributed mortality among men (RD = 0.88, 95% CI = 0.19-1.56) and accidental deaths (RD = 0.54, 95% CI = 0.09-0.99), whereas among women the main effect was an increase in hospital-treated suicide attempts (RD = 1.11, 95% CI = 0.11-2.11).

In Finland, reaching legal drinking ages appears to be associated with substantial short-run increases in mortality and morbidity, concentrated among young men and linked to external and alcohol-related causes. These findings suggest that minimum legal drinking age policies carry important public health costs that should be considered when evaluating alcohol regulation. At age 18 years, where the drinking and driving-licence thresholds coincide, both mechanisms contribute: controlling for driving-licence status reduces hospitalization estimates by approximately one quarter, but a substantial alcohol-access effect remains.