Preloading, exit intoxication related to energy drink usage, and gender differences within night-time entertainment...

Governments frequently introduce legislation to reduce drunkenness and violence in night-time entertainment districts (NEDs). However, there is no study which has looked at inebriation of a large sample of young people exiting a NED. We investigated Breath Approximated Blood Alcohol Concentration (BrAC; grams per decilitre, g/dl) levels as people left Brisbane (Australia) NEDs and measured the effects of preloading, energy drink usage, time of night and gender differences on exit intoxication.

We systematically assessed patrons between November 2015 to March 2019 by administering surveys and breathalysing them as they exited the NEDs. We then analysed only those under the age of 26 years old (n = 3,211) as there was a natural break in the data on energy drink usage for those aged over 25 years old.

This study found that young drinkers leave the NED with an average BrAC of 0.094 g/dl. Consistent with hypotheses, the exit BrAC was significantly and meaningfully higher in preloaders (medium effect size). These preloaders also came into the NEDs later but stayed for the same length of time as non-preloaders. BrAC levels did not significantly differ for those who did or did not use energy drinks during the night. As predicted, gender was not associated with a meaningful difference in alcohol intoxication and consumption. The time of night that patrons were interviewed was positively associated with inebriation levels, however, this association was small (r ≈ 0.1).

With preloading being such a strong predictor for end of night intoxication, and length of time spent in the NED equal between those who do or do not preload, we suggest that to have people less inebriated, they should be encouraged into the NED earlier rather than focusing on their leaving time.