E-cigarette or vaping product use–associated lung injury and state-level cannabis policies

Background: Multiple cases of e-cigarette or vaping product use–associated lung injury (EVALI) have been reported in the USA, which have been attributed to informally obtained cannabis oil vaping devices. This report estimated whether cumulative incidence of EVALI differed according to state-level cannabis policy. Methods: Publicly available information was used to estimate the cumulative incidence of EVALI. Odds of incident EVALI were calculated according to policy status (active, legal adult-use recreational policy vs. no legal access). Figures were statistically compared using chi-square tests. Results: Estimated cumulative incidence of EVALI was 5.19 per 100,000 cannabis users across all states with recreational cannabis policies (95% CI 4.70–5.72), and 15.89 per 100,000 cannabis users across all states with no legal access to cannabis (95% CI 14.88–16.96). Odds of EVALI were 3.06 times higher (95% CI 2.71–3.45) among users living in states with no legal access to cannabis compared to users in states with active recreational policies, with significant differences detected according to policy exposure (χ² = 385.57, p < 0.0001). Conclusions: Estimates suggest there may have been a protective effect of state-level, recreational adult-use cannabis policies on incident EVALI. Effects of specific state-level regulations (e.g., laboratory testing, product quality standards, tracking systems) should be considered alongside additional geographic indices in future assessments of EVALI causes.