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Published on: April 28, 2022
[Early alcohol initiation and increased adult alcohol consumption: cause or indicator?]
L M Geels1, J M Vink, J H D A van Beek
1Vrije Universiteit, Amsterdam, The Netherlands. L.M.Geels@vu.nl
Background:
Early alcohol initiation is strongly associated with increased alcohol consumption and alcohol abuse/dependence in adulthood. The mechanisms that underlie this association are unclear.
Aim:
To examine whether there is a causal link between early alcohol initiation and later alcohol consumption.
Method:
Survey data were collected from twin pairs (age range 18-80) included in the Netherlands Twin Register (NTR). A discordant twin design was used to examine the origin of the link between early alcohol initiation and adult alcohol consumption. Within monozygotic pairs (82-143 pairs), twins who started drinking early were compared to their brother/sister who started drinking later, on frequency of alcohol use, weekly alcohol consumption, number of alcohol intoxications, excessive drinking, alcohol abuse/-dependence, and hazardous drinking. By drawing comparisons within monozygotic pairs, we were able to control for the effects of genes/shared environment. Additional analyses examined the effects of age, sex, and in-/exclusion of lifelong abstainers.
Results:
Within monozygotic twin pairs, the twin who had started drinking early did not differ significantly from his/her brother/sister with respect to future alcohol consumption. Results were independent of age, sex, and in-/exclusion of lifelong abstainers.
Conclusion:
Early alcohol initiation did not have significant causal effects on subsequent alcohol consumption in adulthood and may be an indicator of a predisposition for alcohol consumption. Campaigns aimed at raising the minimum age for alcohol initiation will possibly have only a limited effect on adult alcohol consumption.
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