Department of Health Policy & Management, Yale School of Public Health, New Haven, CT, USA.
Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA.
Drug Alcohol Depend. 2021 Nov 1;228:109086. doi: 10.1016/j.drugalcdep.2021.109086. Epub 2021 Sep 22.
The United States' 2019 outbreak of e-cigarette or vaping-associated lung injuries (EVALI) was linked to an additive most common in informally-sourced vaporizable marijuana concentrates. This study estimates how states' recreational and medical marijuana policies related to their 2019 EVALI incidence and residents' likelihood of vaping as their primary mode of marijuana use.
Multivariable negative binomial regressions estimated associations between states' total 2019 EVALI cases and marijuana policies: recreational legalization, medical legalization only, and whether medical-only policies allowed home cultivation, prohibited combustible use, or had operational dispensaries. Logistic regressions used survey data from the Behavioral Risk Factor Surveillance System's 2016-2019 marijuana supplements to assess how these policies related to past-30-day marijuana users' selection of vaping as their primary mode of use.
EVALI incidence was 42% lower in recreational marijuana states (95%CI=0.339,0.993), versus a positive but statistically insignificant association with medical legalization alone. Adjusting for policy attributes revealed heterogeneity: among medical-marijuana-only states, EVALI incidences were > 60% lower where laws allowed home cultivation (aIRR=0.374; 95%CI=0.196, 0.715). Similarly, among past-30-day marijuana users, odds of vaping as one's primary mode of use were > 40% lower in medical-only states where home cultivation was allowed versus prohibited (aOR=0.588; 95%CI=0.365,0.946).
Marijuana policy attributes linked to lower EVALI incidences were also associated with reduced likelihoods of vaping as one's primary mode of use. As additives in informally-sourced vaping concentrates could drive future EVALI cases, marijuana policy design should account for effects on mode of use in licit and illicit markets, to limit the scope of future outbreaks.
美国 2019 年电子烟或蒸气相关肺损伤（EVALI）的爆发与一种在非正式来源的可蒸发大麻浓缩物中最常见的添加剂有关。本研究估计各州的娱乐和医用大麻政策与 2019 年 EVALI 发病率以及居民将蒸气作为主要大麻使用方式的可能性之间的关系。
多变量负二项回归估计了各州 2019 年 EVALI 总病例数与大麻政策之间的关联：娱乐合法化、仅医疗合法化，以及医疗仅政策是否允许家庭种植、禁止可燃使用或拥有运营中的药房。使用来自行为风险因素监测系统 2016-2019 年大麻补充调查的数据的逻辑回归评估了这些政策与过去 30 天内使用大麻的人中选择蒸气作为主要使用方式之间的关系。
娱乐用大麻州的 EVALI 发病率降低了 42%（95%CI=0.339，0.993），而单独的医疗合法化则呈正相关但无统计学意义。调整政策属性后发现存在异质性：在仅医用大麻州，允许家庭种植的法律使 EVALI 发病率降低了>60%（调整后的发病率比[AIRR]=0.374；95%CI=0.196，0.715）。同样，在过去 30 天内使用大麻的人中，允许家庭种植的医用大麻州选择蒸气作为主要使用方式的可能性降低了>40%（调整后的优势比[aOR]=0.588；95%CI=0.365，0.946）。
与较低的 EVALI 发病率相关的大麻政策属性也与蒸气作为主要使用方式的可能性降低相关。由于非正式来源蒸气浓缩物中的添加剂可能导致未来 EVALI 病例增加，因此大麻政策设计应考虑到在合法和非法市场上对使用方式的影响，以限制未来疫情的范围。
