Rhew Isaac C, Gilson Michael S, Fleming Charles B, Walukevich-Dienst Katherine, Guttmannova Katarina, Patrick Megan E, Lee Christine M
Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, Washington, USA.
Institute for Social Research, University of Michigan, Ann Arbor, Michigan, USA.
Alcohol Clin Exp Res (Hoboken). 2024 May;48(5):955-966. doi: 10.1111/acer.15307. Epub 2024 Apr 1.
An important life-course event with respect to alcohol and cannabis use is turning 21 years of age, which may be associated with increases in use of these substances due to celebrations during the month and easier access to them on and following this birthday. We examined the trajectories of alcohol and cannabis use behaviors in the months leading up to, during, and following the 21st birthday month. We also examined whether the use trajectories vary by college status and baseline levels of use.
We used data from 203 young adults recruited from the Greater Seattle region who turned 21 during the course of the study. Surveys were administered each month for 24 consecutive months. Measures included the typical number of drinks per week for the past month, the frequency of heavy episodic drinking, the number of cannabis use days, and any simultaneous alcohol and cannabis use. Multilevel spline models were run that estimated linear slopes over time at four intervals: (1) up to 1 month before the 21st birthday month; (2) from 1 month before to the month of the 21st birthday; (3) from the 21st birthday month to 1 month following; and (4) from 1 month following the 21st birthday month through all following months.
Alcohol use, generally, and simultaneous alcohol and cannabis use showed sharp increases from the month before the 21st birthday month to the 21st birthday month and decreases following the 21st birthday month. For cannabis use, there were significant increases in the months leading up to the 21st birthday and no other significant changes during other time intervals. Patterns differed by baseline substance use and college status.
Findings from the current study have implications for the timing and personalization of prevention and intervention efforts. Event-specific 21st birthday interventions may benefit from incorporating content targeting specific hazardous drinking behaviors in the month prior to the 21st birthday.
关于酒精和大麻使用，一个重要的人生阶段事件是年满21岁，这可能与这些物质的使用增加有关，原因是在该月有庆祝活动，且在生日当天及之后更容易获取这些物质。我们研究了在21岁生日当月之前、当月以及之后几个月里酒精和大麻使用行为的轨迹。我们还研究了使用轨迹是否因大学就读状况和基线使用水平而有所不同。
我们使用了从大西雅图地区招募的203名在研究过程中年满21岁的年轻成年人的数据。连续24个月每月进行调查。测量指标包括过去一个月每周饮酒的典型杯数、大量饮酒的频率、大麻使用天数以及任何同时使用酒精和大麻的情况。运行了多水平样条模型，该模型在四个时间段估计随时间变化的线性斜率：（1）21岁生日当月之前1个月；（2）从21岁生日当月之前1个月到21岁生日当月；（3）从21岁生日当月到之后1个月；（4）从21岁生日当月之后1个月到所有后续月份。
总体而言，酒精使用以及同时使用酒精和大麻的情况从21岁生日当月之前1个月到21岁生日当月急剧增加，在21岁生日当月之后减少。对于大麻使用，在21岁生日之前的几个月有显著增加，在其他时间段没有其他显著变化。模式因基线物质使用情况和大学就读状况而异。
本研究的结果对预防和干预措施的时机选择及个性化具有启示意义。针对21岁生日这一特定事件的干预措施可能受益于纳入针对21岁生日前一个月特定危险饮酒行为的内容。
