Department of Family Medicine, University of Ottawa, Ottawa, Ontario, Canada.
Bruyère Research Institute, Ottawa, Ontario, Canada.
JAMA Netw Open. 2023 Sep 5;6(9):e2331551. doi: 10.1001/jamanetworkopen.2023.31551.
The impact of nonmedical cannabis legalization on traffic injuries and cannabis involvement in traffic injuries is unclear.
To examine changes in the number and characteristics of cannabis-involved traffic injury emergency department (ED) visits from before to after legalization and subsequent commercialization (ie, increased retail store and product availability) of cannabis in Ontario, Canada.
DESIGN, SETTING, AND PARTICIPANTS: This repeated cross-sectional study examined changes in cannabis- and alcohol-involved traffic injury ED visits in Ontario, Canada, during 3 time periods: prelegalization (January 2010-September 2018), legalization with product and retail store restrictions (October 2018-February 2020), and commercialization with new products and expanded number of stores, which coincided with the COVID-19 pandemic (March 2020-December 2021). All individuals aged 16 years and older eligible for Ontario's Universal Health Coverage were included. Season- and time-adjusted quasi-Poisson models were used to generate rate ratios with 95% CIs. Data were analyzed from March to April 2023.
Quarterly counts of cannabis-involved ED visits for traffic injury.
There were 947 604 traffic injury ED visits, of which 426 (0.04%) had documented cannabis involvement and 7564 (0.8%) had documented alcohol involvement. Of the 418 individuals with documented cannabis involvement, 330 (78.9%) were male, 109 (25.6%) were aged 16 to 21 years (mean [SD] age at visit, 30.6 [12.0] years), and 113 (27.0%) had an ED visit or hospitalization for substance use in the 2 years before their traffic injury ED visit. Annual rates of cannabis-involved traffic injury ED visits increased 475.3% over the study period (0.18 visits per 1000 total motor vehicle collisions in 2010 to 1.01 in 2021). Over the same period, alcohol-involved traffic injury ED visits increased by 9.4% (8.03 in 2010 to 8.79 per 1000 traffic injury ED visits in 2021). Legalization with restrictions was associated with a 94% increase in the quarterly rate of cannabis involvement in traffic injury ED visits relative to prelegalization (adjusted rate ratio [aRR], 1.94; 95% CI, 1.37-2.75). Commercialization/COVID-19 was associated with a greater increase of 223% in rates (aRR, 3.23; 95% CI, 2.42-4.33). After adjusting for time trends before legalization, only commercialization/COVID-19 was associated with increased rates. Male sex (adjusted odds ratio [aOR], 3.38; 95% CI, 2.66-4.29), living in the lowest-income neighborhood (aOR, 1.92; 95% CI, 1.39-2.67), being aged 19 to 21 years (aOR, 4.67; 95% CI, 3.27-6.67), and having a prior cannabis-related ED visit (aOR, 8.03; 95% CI, 5.85-11.02) were all positively associated with cannabis involvement during a traffic injury ED visit.
This cross-sectional study found large increases in cannabis involvement in ED visits for traffic injury over time, which may have accelerated following nonmedical cannabis commercialization. Although the frequency of visits was rare, they may reflect broader changes in cannabis-impaired driving. Greater prevention efforts, including targeted education and policy measures, in regions with legal cannabis are indicated.
非医用大麻合法化对交通伤害和大麻在交通伤害中的作用的影响尚不清楚。
研究在加拿大安大略省大麻非医用合法化和随后商业化（即增加零售商店和产品供应）前后，与大麻有关的交通伤害急诊（ED）就诊人数和特征的变化，在此期间恰逢 COVID-19 大流行。
设计、地点和参与者：这项重复的横断面研究在三个时间段内研究了安大略省与大麻和酒精有关的交通伤害 ED 就诊人数的变化：非医用合法化前（2010 年 1 月至 2018 年 9 月）、产品和零售商店限制的合法化后（2018 年 10 月至 2020 年 2 月）以及产品和零售商店限制的商业化后（新的产品和更多商店，恰逢 COVID-19 大流行）（2020 年 3 月至 2021 年 12 月）。所有符合安大略省全民医疗保险的 16 岁及以上的人都包括在内。使用季节和时间调整的拟泊松模型生成具有 95%置信区间的率比。数据于 2023 年 3 月至 4 月进行分析。
与交通伤害有关的大麻急诊就诊的季度数量。
有 947604 例交通伤害 ED 就诊，其中 426 例（0.04%）有记录的大麻参与，7564 例（0.8%）有记录的酒精参与。在有记录的大麻参与的 418 人中，330 人（78.9%）为男性，109 人（25.6%）年龄在 16 至 21 岁（就诊时的平均[SD]年龄为 30.6[12.0]岁），113 人（27.0%）在交通伤害 ED 就诊前的 2 年内有过物质使用的 ED 就诊或住院治疗。在研究期间，与大麻有关的交通伤害 ED 就诊的年度发生率增加了 475.3%（2010 年每 1000 次总机动车碰撞 0.18 次，2021 年增加到 1.01 次）。同期，与酒精有关的交通伤害 ED 就诊增加了 9.4%（2010 年每 1000 次交通伤害 ED 就诊 8.03 次，2021 年为 8.79 次）。有条件限制的合法化与交通伤害 ED 就诊中大麻参与的季度率增加了 94%（调整后的率比[ARR]，1.94；95%CI，1.37-2.75）。商业化/COVID-19 与增加了 223%的比率有关（ARR，3.23；95%CI，2.42-4.33）。在调整了合法化前的时间趋势后，只有商业化/COVID-19 与增加的比率有关。男性（调整后的优势比[aOR]，3.38；95%CI，2.66-4.29）、居住在收入最低的社区（aOR，1.92；95%CI，1.39-2.67）、年龄在 19 至 21 岁（aOR，4.67；95%CI，3.27-6.67）和之前有过与大麻有关的 ED 就诊（aOR，8.03；95%CI，5.85-11.02）都与交通伤害 ED 就诊中的大麻参与呈正相关。
这项横断面研究发现，随着时间的推移，与大麻有关的交通伤害 ED 就诊人数大幅增加，这可能在非医用大麻商业化后加速。尽管就诊频率很少，但它们可能反映了大麻影响驾驶行为的更广泛变化。在有合法大麻的地区，需要加强预防工作，包括有针对性的教育和政策措施。
