Changes in Sales of E-Cigarettes, Cigarettes, and Nicotine Replacement Therapy Products Before, During, and After the EVALI Outbreak

Xu Wang, PhD; Yoonsang Kim, PhD; Katrina F. Trivers, PhD, MSPH; Michael A. Tynan, MPH; Sundar S. Shrestha, PhD; Sherry Emery, PhD; Mateusz Borowiecki, BA; Karen Hacker, MD, MPH


Prev Chronic Dis. 2022;19(12):E86 

In This Article

Abstract and Introduction


Introduction: In 2019, an outbreak of e-cigarette, or vaping, product use–associated lung injury (EVALI) occurred in the US. We used Nielsen retail sales data to assess trends in sales of e-cigarettes, cigarettes, and nicotine replacement therapy (NRT) products before, during, and after the EVALI outbreak.

Methods: Monthly unit sales of e-cigarettes, cigarettes, and NRT products overall and by product type were assessed during January 2019 through June 2020 by using an interrupted time series model. Two time points were specified at the period ending July 13, 2019, and the period ending February 22, 2020, to partition before, during, and after the outbreak period. Sales trends by aggregated state-level EVALI case prevalence (low, medium, and high) were assessed to investigate interstate variations in changes of sales coinciding with the EVALI outbreak.

Results: Monthly e-cigarette sales increased 3.5% (P < .001) before the outbreak and decreased 3.1% (P < .001) during the outbreak, with no significant changes after the outbreak. Monthly cigarette sales increased 1.6% (P < .001) before the outbreak, decreased 1.8% (P < .001) during the outbreak, and increased 2.7% (P < .001) after the outbreak. NRT sales did not change significantly before or during the outbreak but decreased (2.8%, P = .01) after the outbreak. Sales trends by state-level EVALI case prevalence were similar to national-level sales trends.

Conclusion: Cigarette and e-cigarette sales decreased during the EVALI outbreak, but no changes in overall NRT sales were observed until after the outbreak. Continued monitoring of tobacco sales data can provide insight into potential changes in use patterns and inform tobacco prevention and control efforts.


Tobacco use remains the leading cause of preventable disease and death in the United States.[1,2] Disease and death from tobacco use is overwhelmingly caused by combusted tobacco products.[1] Since the first Surgeon General's Report on smoking and health, cigarette smoking among US adults declined from about 43% in 1964 to 14% in 2019.[2,3] While the prevalence of cigarette smoking continues to decline among US adults and youth, the prevalence of e-cigarette use increased since their introduction to the US market in 2007, reaching a prevalence of 4.5% among adults and 20% among youth by 2019.[3,4] Although current use of e-cigarettes decreased in 2020 to 3.3% among US adults and 13% among youth (middle- and high-school students),[5,6] e-cigarettes have been the most commonly used tobacco product among US middle (grades 6–8) and high school (grades 9–12) students since 2014.[7]

E-cigarette aerosol can contain harmful and potentially harmful substances.[8] Most e-cigarettes sold contain nicotine, a highly addictive drug that can harm brain development, which continues until about age 25.[9] E-cigarette use can also increase the risk of combustible cigarette use among youth and may cause sustained tobacco use among youth.[10,11] Many people may consider e-cigarette use as a way to quit cigarette smoking.[12,13] However, there is inadequate evidence to conclude that e-cigarettes, in general, increase smoking cessation, and e-cigarettes are not currently approved by the US Food and Drug Administration (FDA) as a smoking cessation aid.[2] Cessation medications approved by the FDA for use in adults aged older than 18 include bupropion, varenicline, and 5 forms of nicotine replacement therapy (NRT; nicotine patch, gum, lozenge, inhaler, and nasal spray). Because e-cigarettes can harm the developing brain, e-cigarettes should never be used by youth, young adults, and women who are pregnant.[8] Adults who do not use tobacco products should not start using e-cigarette, or vaping, products.[2]

In 2019, an outbreak of e-cigarette, or vaping, product use–associated lung injury (EVALI) occurred in the US. Starting in August 2019, the Centers for Disease Control and Prevention (CDC), the FDA, and state and local health authorities investigated the nationwide EVALI outbreak. The number of EVALI cases reported to CDC peaked in September 2019 and then had a gradual and persistent decline.[14] As of February 18, 2020, a total of 2,807 hospitalized EVALI cases were reported to CDC from all 50 states, the District of Columbia, the US Virgin Islands, and Puerto Rico. Investigative results indicate that tetrahydrocannabinol (THC)-containing e-cigarette, or vaping, products — particularly those obtained from informal sources like family, friends, or in-person or online dealers — were linked to most EVALI cases, and vitamin E acetate, an additive in THC devices, played a major role in the outbreak.[14,15] While most EVALI patients (82%) reported using THC-containing products and more than half (57%) reported also using nicotine-containing products, about 1 in 7 patients (14%) reported exclusive use of nicotine-containing products.[14]

Because of the initial uncertainty around the cause of EVALI,[16] the outbreak may have prompted changes in tobacco use and cessation behaviors. Although not necessarily reflective of use patterns, retail sales data may provide a useful barometer to provide insight into changes in e-cigarette use, cigarette smoking, and tobacco use cessation patterns. Some studies have assessed trends in sales or use of cigarettes and e-cigarettes.[15,17–19] However, these studies did not cover the period of the EVALI outbreak. One study did assess the e-cigarette unit sales in the US during September 2014 through May 2020, which covered the EVALI period,[20] but like other studies,[15,17–19] it did not assess the trends in sales or use of NRT around the EVALI outbreak. Our study used 4-week aggregate retail sales data to identify emerging trends in sales of e-cigarettes, cigarettes, and NRT products before, during, and after the outbreak. Sales trends by states with low, medium, and high EVALI case prevalence were also assessed to investigate variations in changes of sales coincident with the EVALI outbreak at the state level.