Acute Next-Day Effects of Alcohol Use on Daily Cognitive Functioning Among Young Adults: Protocol for a 21-Day Diary Study.

Background: Young adults exhibit the highest rates of binge drinking and heavy alcohol use of any age group. Blackout drinking, or alcohol-induced memory loss, is a negative consequence of heavy drinking and is common among young adults. Alcohol use has been found to affect postintoxication cognitive functioning, especially among those who have experienced blackout drinking. However, there have been a limited number of studies that have assessed alcohol use and cognitive functioning via ecological momentary assessment (EMA). This methodology allows researchers to have a better understanding of the association between alcohol use and next-day cognition as well as blackout drinking and potential moderators between these associations.

Objective: The primary objective of the current study is to examine the association between alcohol use and next-day cognitive functioning among young adults. Multiple indices of alcohol use including blackout drinking and cognitive functioning will be examined. Additionally, moderators of these associations (at the day- and person-levels) will be examined. Potential moderators include other substance use, sleep, mood, hangover symptoms, and participant characteristics (eg, baseline alcohol use severity).

Methods: Eligible participants had to be aged between 18-25 years, a current university or college student, residing in the Eastern time zone, endorsing heavy episodic drinking at least 2 times in a typical month, and reporting a blackout drinking episode at least once in the previous year. After completing a web-based screening survey, eligible participants were directed to a web-based baseline survey that asked about alcohol use, self-reported cognitive functioning, objective cognitive assessments, and demographic information. Participants were then sent 5 surveys a day for 21 consecutive days, which asked about substance use, sleep, mood, and self-reported and objective cognitive functioning. Multilevel models will be used to examine day-level associations between alcohol use and cognitive functioning.

Results: A total of 304 participants were eligible, with 297 participants completing at least 1 EMA survey and cognitive assessment during the 21-day period. Data were collected between November 2023 and May 2024.

Conclusions: The primary aim of this study is to examine the association between alcohol use (including blackout drinking) and next-day cognitive functioning, with a secondary objective of identifying potential day- and person-level moderators of these associations. Findings from the study may help inform momentary interventions and identify characteristics of young adults that may put them at higher risk for experiencing negative consequences.

International registered report identifier (irrid): RR1-10.2196/77584.