Cannabis Vape Product Sales in California Following CDC's Initial Advisory About Lung Injuries

Introduction: The 2019 outbreak of e-cigarette or vaping product use-associated lung injury (EVALI) is believed to have been caused by vitamin E acetate, an additive used in some cannabis vaporizer products. Previous studies have primarily focused on changes in sales of electronic nicotine delivery systems following the initial advisory issued by the Centers for Disease Control (CDC) on August 17, 2019. The present study is intended to examine variation by age groups in sales of regulated cannabis vape products in the state of California before, during, and after the outbreak. Methods: Weekly sales revenue of cannabis vape products (from January 1, 2018, to December 31, 2020) was obtained from a sample of recreational cannabis retailers licensed in California. An interrupted time series analysis, using AutoRegressive, Integrated, Moving Average methods, was employed to estimate changes in the sales and market share of cannabis vape products in the weeks following the CDC advisory. Results: The total volume of regulated cannabis vape product sales increased substantially over the 3-year study period (2018-2020). Sales and market share of cannabis vape products, however, declined in both young and older adults immediately following the advisory, rebounding to pre-EVALI levels only for the young adults. For sales, the potential EVALI effect following the CDC's advisory equates to an 8.0% and 2.2% decline below expected levels in the older and young adults, respectively. Conclusions: The differential age effect on sales may reflect concerns regarding health effects of cannabis vaping products and greater awareness of the outbreak among older adults. Findings highlight the importance of informing consumers about health risks associated with using cannabis vape products acquired from regulated versus illicit sources.