Center for Alcohol and Addiction Studies, Brown University, Box G-S121-4, Providence, RI, 02912, United States.
Center for Alcohol and Addiction Studies, Brown University, Box G-S121-4, Providence, RI, 02912, United States; University of Saint Joseph, 1678 Asylum Avenue, West Hartford, CT, 06117, United States.
Drug Alcohol Depend. 2020 Jul 1;212:107986. doi: 10.1016/j.drugalcdep.2020.107986. Epub 2020 Apr 26.
Alcohol and marijuana are frequently co-used with overlapping effects. However, the absence of consistent operational definitions delineating simultaneous alcohol and marijuana use (SAM) from concurrent use (CAM) challenges consistent inferences about these behaviors. This study first examined whether daily alcohol and marijuana co-use predicted substance-use related consequences and subjective intoxication; and then evaluated whether competing operationalizations of SAM and CAM were associated with differences in these outcomes on co-use days.
A sample of 341 young adult college students who reported past-month use of both alcohol and marijuana "at the same time so that their effects overlapped" completed a two-wave survey with paired 28-day daily experience sampling bursts examining alcohol and marijuana co-use. Outcomes were (a) daily substance-use related consequences; and (b) daily subjective intoxication. Focal predictors were daily drinks and marijuana uses; daily co-use versus single-substance use (Aim 1) or CAM versus SAM (Aim 2); and their interaction.
Participants reported more negative consequences on co-use days versus marijuana-only days and greater subjective intoxication relative to alcohol or marijuana-only days. Competing operationalizations of SAM, defined as daily co-use occurring within 1-240 min in increments of 1 min, found no difference in consequences or subjective intoxication regardless of operationalization.
Co-use days involve greater risk than alcohol-only or marijuana-only days. Although there was no evidence of additional daily risk from simultaneous use regardless of the timeframe used to operationalize it, investigating these effects remains challenging due to the generally small timeframe between substances on co-use days in this sample.
酒精和大麻经常同时使用，产生重叠的影响。然而，由于缺乏明确界定同时使用酒精和大麻（SAM）与并发使用（CAM）的一致操作定义，这给这些行为的一致推断带来了挑战。本研究首先考察了每日酒精和大麻共同使用是否预测了与物质使用相关的后果和主观醉酒；然后评估了 SAM 和 CAM 的竞争操作定义是否与这些共同使用日的结果差异相关。
本研究招募了 341 名报告过去一个月内同时使用过酒精和大麻的成年大学生，他们的使用方式是“同时使用，使它们的效果重叠”。研究采用了两波调查和配对的 28 天每日经验抽样爆发，调查了酒精和大麻的共同使用。结果包括：（a）每日与物质使用相关的后果；和（b）每日主观醉酒。焦点预测因素是每日饮酒和大麻使用量；每日共同使用与单一物质使用（目标 1）或 CAM 与 SAM（目标 2）；以及它们的交互作用。
与大麻单独使用日相比，参与者在共同使用日报告了更多的负面后果，并且与仅使用酒精或大麻相比，主观醉酒程度更高。SAM 的竞争操作定义为在 1-240 分钟内的每日共同使用，每隔 1 分钟进行一次递增，无论操作定义如何，在后果或主观醉酒方面均无差异。
共同使用日比仅使用酒精或大麻日风险更大。尽管无论使用何种时间框架来操作，同时使用都没有额外的每日风险证据，但由于在这个样本中，共同使用日之间的物质使用时间通常较短，因此调查这些影响仍然具有挑战性。
