Genetic influences on alcohol-related hangover.
AIMS
To quantify the relative contributions of genetic and environmental factors to alcohol hangover.


DESIGN
Biometric models were used to partition the variance in hangover phenotypes.


SETTING
A community-based sample of Australian twins.


PARTICIPANTS
Members of the Australian Twin Registry, Cohort II who reported consuming alcohol in the past year when surveyed in 2004-07 (n = 4496).


MEASUREMENTS
Telephone interviews assessed participants' frequency of drinking to intoxication and frequency of hangover the day after drinking. Analyses examined three phenotypes: hangover frequency, hangover susceptibility (i.e. residual variance in hangover frequency after accounting for intoxication frequency) and hangover resistance (a dichotomous variable defined as having been intoxicated at least once in the past year with no reported hangovers).


FINDINGS
Genetic factors accounted for 45% [95% confidence interval (CI) = 37-53%] and 40% (95% CI = 33-48%) of the variation in hangover frequency in men and women, respectively. Most of the genetic variation in hangover frequency overlapped with genetic contributions to intoxication frequency. Genetic influences accounted for 24% (95% CI = 14-35%) and 16% (95% CI = 8-25%) of the residual hangover susceptibility variance in men and women, respectively. Forty-three per cent (95% CI = 22-63%) of the variation in hangover resistance was explained by genetic influences, with no evidence for significant sex differences. There was no evidence for shared environmental influences for any of the hangover phenotypes.


CONCLUSIONS
Individual differences in the propensity to experience a hangover and of being resistant to hangover at a given level of alcohol use are genetically influenced.