The event-level rewards of high-intensity drinking may balance the risks
Background: Young adults reporting high intensity drinking (HID, 8+/10+ drinks for females/males) are more likely to experience negative alcohol consequences than those who do not, and drinking to HID levels on a given day may confer a higher risk for negative consequences than heavy episodic drinking (HED, 4+/5+ drinks for females/males). Data on positive consequences experienced at different drinking levels may provide insight into the positive reinforcement of HID. Moreover, identifying for whom (i.e., sex) and under what conditions (i.e., drinking duration) HID results in risk and reward (negative/positive consequences) may inform intervention approaches. We hypothesized that both males and females would report more negative consequences and more positive consequences on HID vs HED days, but the number of drinks consumed beyond HID thresholds would be more strongly associated with negative consequences for females than males. On HID days, we also expected shorter drinking durations would increase reports of negative consequences.
Methods: Young adults reporting HID (N=203, 57% female, Mage=22) completed a 28-day ecological momentary assessment protocol measuring alcohol use and consequences. Hierarchical linear modeling (HLM, days nested in person) tested event-level drinking levels as predictors of negative consequences, controlling for age, study day, and weekend/weekday. Parallel analyses were run on positive consequences, and sex was tested as a moderator.
Results: Of 2,468 drinking days, 666 (27%) involved HID and 939 (38%) involved HED. Descriptively, many specific negative consequences were at least twice as likely on HID days (e.g., memory loss: 36% HID vs. 14% HED days; hangover: 37% vs 16%). Differences in positive consequences were less extreme (e.g., improved mood: 60% vs. 54%; more sociable: 70% vs. 59%). In HLM models, HID (vs HED) increased reports of both negative and positive consequences, with no differences by sex. On HID days, the number of drinks consumed beyond the HID threshold was associated with a higher likelihood of negative (but not a greater number of positive) consequences. In contrast to hypotheses, this effect did not differ by sex. Also in contrast to hypotheses, drinking duration was not significantly related to negative or positive consequences on HID days.
Conclusions: At the event level, HID increased the likelihood of negative and positive consequences experienced. This suggests event-level rewards of HID may help explain why this risky behavior recurs. However, the positive consequences of drinking did not continue increasing at levels of drinking beyond HID. From a prevention and intervention perspective, young adults may benefit from understanding their personal drinking limit of diminishing returns (in this sample, 8-10 drinks).
