Changing the minimum legal drinking age--its effect on a central city emergency department

To quantify the effect of a recent national law change on the presentation of ethanol intoxicated patients to a central city Emergency Department (ED).

All records of ethanol intoxicated patients presenting to the ED for twelve months before and after the change to the minimum legal drinking age were studied. Each patient was classified as having laboratory confirmed intoxication, clinical suspicion only, or no record of intoxication. Three age groups were identified, 15-17 year olds, eighteen and nineteen year olds and over 20 year olds. Within each age group the proportion of presentations with ethanol intoxication was compared across the two time periods.

The number of intoxicated 18 and 19 year olds increased in the twelve months after the national law change from 66 to 107 (52 to 80 for laboratory confirmed intoxication and fourteen to 27 for clinical suspicion only). This represented an increase in the proportion of presentations in this age group with intoxication (p=0.009) from 2.9% to 4.4%, a 50% increase (RR=1.51, 95%CI 1.11-2.03). There was no evidence of an increase in the proportion intoxicated for those over nineteen years (3.4% vs 3.3%, p=0.48, RR=0.97, 95%CI=0.89-1.06) although the numbers increased slightly (963 to 992). However there was a worrying trend for an increase in the 15-17 year olds, with numbers increasing from 72 to 95 and the proportion increasing from 5.0% to 6.7% (p=0.07, RR=1.35, 95%CI=0.98-1.88).

The recent lowering of the minimum legal drinking age from 20 to eighteen years has resulted in increased presentations to the ED of intoxicated eighteen and nineteen year olds. A similar trend was seen in the 15-17 year olds.