David Theodore Levy

Georgetown University | GU · Lombardi Comprehenisive Cancer Center

An analysis of 1771 Canadian adults who smoke or used to smoke cigarettes was conducted using data from the 2022 International Tobacco Control Four Country Smoking and Vaping Survey. Using weighted data, we estimated the prevalence of Canadian adults who tried to quit smoking between 2020 and 2022, and the use of a nicotine vaping product (NVP) and...

Nous avons mené une analyse portant sur 1 771 adultes canadiens qui fument ou fumaient des cigarettes en nous fondant sur les données de l’Enquête sur le tabagisme et le vapotage dans quatre pays menée en 2022 par le Projet international d’évaluation de la lutte antitabac. En utilisant des données pondérées, nous avons estimé la prévalence des tent...

Importance Research shows that Tobacco 21 (T21) policies with a minimum legal access age for tobacco products of 21 years reduce smoking, yet their impact varies across US states due to differences in smoking behaviors, mortality rates, and policy coverage. Objective To quantify potential reductions in smoking-attributable mortality associated wit...

Objective This study updates a previous paper that examined trends in the sale of cigarettes and heated tobacco products (HTPs) in Japan between 2011 and part way through 2019. The current study includes complete unit sales data through 2023. Methods Data on cigarette and HTP sales were obtained from public sources available from the websites and...

Objective This study estimated prevalence of current electronic nicotine delivery systems (ENDS) used by US adults who smoked cigarettes or formerly smoked in 2022 and assessed ENDS flavors, devices, and brands used most often. Methods Data are from the 2022 US ITC Smoking and Vaping Survey. Respondents were recruited from a web panel of a nationa...

Introduction The use of cigarettes and electronic nicotine delivery system (ENDS) has likely changed since 2019 with the rise of pods and disposables, the lung injuries outbreak, flavour bans, Tobacco 21 and the COVID-19 pandemic. Methods Using the Population Assessment of Tobacco and Health Study, we applied a multistate transition model to 28 06...

Background The health consequences of polytobacco use are not well understood. We evaluated prospective associations between exclusive, dual, and polytobacco use and diagnosed bronchitis, pneumonia, or chronic cough among US youth. Methods Data came from Waves 1–5 of the Population Assessment of Tobacco and Health Study. We categorized time-varyin...

Introduction Half of adult cigar users report flavored cigars as their usual brand. The FDA proposed prohibiting “all characterizing flavors in cigars” and “menthol… in cigarettes.” We provide evidence on cigar and cigarette transitions and a framework to assess the impact of a U.S. flavored cigar ban. Methods Using PATH Waves 1-4, we estimated us...

Introdution Studies have reported that the rapid rise in heated tobacco product (HTP) sales in Japan accompanied an accelerated decline in cigarette sales. However, these studies do not distinguish whether those who previously smoked cigarettes became dual users with HTPs (smoking fewer cigarettes) or instead switched completely to HTPs. If HTPs pr...

Introduction Oral nicotine pouches (ONPs) are a new class of nicotine products. This scoping review summarizes evidence on ONPs and explores their potential public health impact. Aims and Methods We conducted a structured literature search for empirical studies across three electronic databases through January 10, 2024. Outcomes included ONP produ...

Background We estimated the prevalence and mortality risks of preserved ratio impaired spirometry (PRISm) and chronic obstructive pulmonary disease (COPD) in the US adult population. Methods We linked three waves of pre-bronchodilator spirometry data from the US National Health and Nutritional Examination Survey (2007–2012) with the National Death...

Objective To develop the Mexico Smoking and Vaping Model (Mexico SAVM) to estimate cigarette and electronic nicotine delivery systems (ENDS) prevalence and the public health impact of legalizing ENDS use. Methods SAVM, a cohort-based discrete-time simulation model, compares two scenarios. The ENDS-Restricted Scenario estimates smoking prevalence an...

Introduction While retail sales and retailer inspection studies generally indicate high compliance with state sales restrictions on Nicotine Vaping Products (NVPs) within the restricted area, studies using survey data generally indicate that most users could readily continue gaining access to restricted NVPs. Our study bridges a gap in the current...

Background and Aims Nicotine vaping products (NVPs) can potentially help adult tobacco users quit smoking. This study evaluated how adult consumers compare the costs between NVPs and cigarettes. Method We used data from the US arm of the 2016–2020 International Tobacco Control Four Country Smoking and Vaping (ITC 4CV) surveys to perform a multinom...

Background While regular cigar smoking is believed to carry similar health risks as regular cigarette smoking, the impact of cigar use, alone or in combination with cigarettes, on obstructive pulmonary disease (COPD) has not been well characterized. The purpose of this study was to examine the prospective association between exclusive and dual ciga...

Background The health consequences of polytobacco use are still well not understand. We evaluated prospective associations between exclusive, dual, and polytobacco use and diagnosed bronchitis, pneumonia, or chronic cough among US youth. Methods Data came from Waves 1–5 of the Population Assessment of Tobacco and Health Study. We categorized time-...

Introduction Achieving cessation in people with established smoking patterns remains a challenge. Increasing cigarette prices has been one of the most effective strategies for lowering smoking rates. It remains unclear how effective it has been in encouraging cessation among adults in recent years and how the effectiveness varies by sociodemographi...

Importance President Biden recently prioritized the fight against smoking as key to reducing cancer mortality. Objective To assess trends in smoking and illuminate the association between smoking and reducing deaths due to cancer. Design, Setting, and Participants This cross-sectional study used responses to National Health Interview Surveys from...

Background Simulation models play an increasingly important role in tobacco control. Models examining the impact of nicotine vaping products (NVPs) and smoking tend to be highly specialized and inaccessible. We present the Smoking and Vaping Model (SAVM),a user-friendly cohort-based simulation model, adaptable to any country, that projects the publ...

INTRODUCTION We used a simulation model to assess the feasibility of reaching the tobacco endgame target (reducing the smoking prevalence to below 5% by 2050) and explored potential implementation strategies. METHODS The impact of strengthened tobacco-control policies on smoking prevalence was analyzed using Korea SimSmoke, a discrete-time Markov...

Introduction The use of cigarettes and electronic nicotine delivery system (ENDS) has likely changed since 2019 with the rise of pods and disposables, the outbreak of lung injuries related to vaping THC, flavor bans, and the COVID pandemic. We analyzed patterns of initiation, cessation, and transitions between cigarettes, ENDS, and dual use before...

Objectives: The public health impact of nicotine vaping products (NVPs) is subject to complex transitions between NVP and cigarette use. To circumvent the data limitations and parameter instability challenges in modeling transitions, we indirectly estimate NVPs' impact on smoking prevalence and resulting smoking-attributable deaths using the SimSm...

Philip Morris International’s recent purchase of Swedish Match may prove to be a vital tobacco industry development. We focus on PMIs potential progress in moving from primarily selling cigarettes toward primarily selling noncombustible nicotine delivery products (NCNDPs). We also consider the potential contribution of the acquisition to industry t...

Introduction: Tobacco companies frequently distribute coupons for their products. This marketing tactic may be particularly effective among young adults, who tend to be especially price-sensitive. Young adulthood is also a stage during which many individuals initiate established cigarette smoking and are especially vulnerable to the effects of tob...

Identifying determinants of smoking cessation is critical for developing optimal cessation treatments and interventions. Machine learning (ML) is becoming more prevalent for smoking cessation success prediction in treatment programs. However, only individuals with an intention to quit smoking cigarettes participate in such programs, which limits th...

Purpose: Electronic Nicotine Delivery Systems (ENDS) use among adolescents has increased greatly over the past decade, but its impact on chronic respiratory health conditions, like asthma, is not fully understood. Methods: We examined data from Waves 1-5 (2013-2019) of the Population Assessment of Tobacco and Health Study using discrete time haz...

Introduction: Cigarette smoking continues to pose a threat to public health. Identifying individual risk factors for smoking initiation is essential to further mitigate this epidemic. To our knowledge, no study today has used Machine Learning (ML) techniques to automatically uncover informative predictors of smoking onset among adults using the Po...

Objective Electronic nicotine delivery systems (ENDS) products have emerged as the most popular alternative to combustible cigarettes. However, ENDS products contain potentially dangerous toxicants and chemical compounds, and little is known about their health effects. The aim of the present study was to examine the prospective association between...

Importance: The prevalence of electronic nicotine delivery systems (ENDS) use has increased, leading to a concern about their respiratory health outcomes. It is unclear whether ENDS use increases the risk of wheezing, a common symptom of respiratory conditions. Objective: To provide an analysis of the longitudinal association between ENDS and ci...

The Cancer Intervention and Surveillance Modeling Network (CISNET) Lung Working Group age-period-cohort methodology to study smoking patterns can be applied to tackle important issues in tobacco control and public health. This paper summarizes the analyses of smoking patterns in the U.S. by race/ethnicity, educational attainment, and family income...

Little is known about the respiratory health effects of dual (two products) and polytobacco (three or more products) use among youth in the United States. Thus, we followed a longitudinal cohort of youth into adulthood using data from Waves 1-5 (2013-2019) of the Population Assessment of Tobacco and Health Study, examining incident asthma at each f...

Introduction It is unknown how recent changes in the tobacco product marketplace have impacted transitions in cigarette and electronic nicotine delivery system (ENDS) use. Methods A multistate transition model was applied to 24 242 adults and 12 067 youth in waves 2–4 (2015–2017) and 28 061 adults and 12 538 youth in waves 4 and 5 (2017–2019) of t...

Introduction: Understanding the relationship between ENDS use and chronic obstructive pulmonary disease and other respiratory conditions is critical. However, most previous studies have not fully adjusted for cigarette smoking history. Methods: Using Waves 1-5 of the U.S. Population Assessment of Tobacco and Health study, the association between...

Background: Electronic nicotine delivery systems (ENDS) come in numerous flavors and may aid smoking cessation. This systematic review examines evidence on the role of ENDS flavors in smoking cessation. Methods: We searched EMBASE OVID, PsychInfo, and Medline databases for studies that: 1) examined cigarette cessation outcomes for persons using...

U.S. smoking-related disparities persist, but data evaluating how smoking patterns across diverse populations have changed by birth cohort are lacking. Worldwide, smoking continues to exact harm, especially to low- and middle-income nations with less historical data for smoking analyses. The Cancer Intervention and Surveillance Modeling Network (CI...

Introduction: Smoking prevalence has decreased considerably in Brazil from 34.8% in 1989 to 12.6% in 2019 owing to the implementation of strong tobacco control policies. However, recent data show that the downward trend may be stagnating. Detailed analyses of historical smoking patterns by birth cohort could guide tobacco control decision making i...

Background: Some cigarette companies have started to talk about replacing cigarettes with less harmful alternatives, which might include nicotine vaping products (NVPs), heated tobacco products (HTPs) and oral nicotine delivery products (ONDPs). We consider market competition as a primary driver of whether cigarette companies follow through on the...

Background: Electronic cigarettes (ECs) are often marketed as a safer alternative to combustible tobacco products. The global EC market has rapidly expanded since their introduction, creating an urgent need for research describing the toxicity and chemical composition of ECs. We conducted an umbrella review to summarize the evidence from existing...

Introduction Little is known about how U.S. smoking patterns of initiation, cessation, and intensity vary by birth cohort across education levels or how these patterns may be driven by other demographic characteristics. Methods Smoking data for adults aged ≥25 years was obtained from the National Health Interview Surveys 1966–2018. Age-period-coho...

Introduction In the U.S., low-income individuals generally smoke more than high-income individuals. However, detailed information about how smoking patterns differ by income, especially differences by birth cohort, is lacking. Methods Using the National Health Interview Survey 1983–2018 data, individual family income was calculated as a ratio of t...

Introduction Smoking rates across U.S. states have declined at different rates over time because some states have progressive tobacco control policies, whereas others have yet to adopt them. Therefore, each state has its own unique historical experience of smoking initiation, cessation, and prevalence. This study characterizes smoking histories for...

Introduction U.S. smoking prevalence varies greatly by race/ethnicity. However, little is known about how smoking initiation, cessation, and intensity vary by birth cohort and race/ethnicity. Methods Adult smoking data were obtained from the 1978–2018 National Health Interview Surveys. Age‒period‒cohort models with constrained natural splines were...

Introduction It is unknown how recent changes in the tobacco product marketplace have impacted transitions in cigarette and electronic nicotine delivery system (ENDS) use. Methods A multistate transition model was applied to 24,242 adults and 12,067 youth in Waves 2–4 (2015–2017) and 28,061 adults and 12,538 youth in Waves 4–5 (2017–2019) of the P...

Objective To synthesize the outcomes of policy evaluations of flavoured electronic nicotine delivery systems (ENDS) restrictions. Data sources PubMed, Scopus, Embase and Web of Science before May 3, 2022. Study selection Studies that report sales, behaviour, or compliance outcomes related to implemented or hypothetical ENDS flavour restrictions....

Identifying determinants of smoking cessation is critical for developing optimal cessation treatments and interventions. Machine learning (ML) is becoming more prevalent for smoking cessation success prediction in treatment programs. However, only individuals with an intention to quit participate in such programs, which limits the generalizability...

Introduction: To help offset the increased price of cigarettes and promote brand loyalty, tobacco companies distribute coupons, particularly to price-sensitive consumers. Few studies, however, have examined the longitudinal association between coupon receipt and smoking cessation. Methods: Using adult data from Waves 1-5 (2013-2019) of the Popul...

Aims: To estimate associations between e-cigarette flavour and smoking cessation and study product use at 6 months or longer. Methods: Secondary analysis of data from a living systematic review, with meta-analyses and narrative synthesis, incorporating data up to Jan 2022. Included studies provided people who smoked combustible cigarettes with n...

This study examined reasons why adults who currently smoke or formerly smoked cigarettes use nicotine vaping products (NVPs) by vaping frequency (daily vs. weekly) stratified by smoking status. This cross-sectional study included 3070 adults from the 2020 ITC Four Country Smoking and Vaping Survey (Australia, Canada, England, United States) who rep...

Markets for nicotine vaping products (NVPs) and heated tobacco products (HTPs) have grown as these products became positioned as harm-reduction alternatives to combusted tobacco products. Herein, we present a public health decision-theoretic framework incorporating different patterns of HTP, NVP, and cigarette use to examine their impacts on popula...

Introduction: While many studies have examined the association between e-cigarette use and smoking cessation, fewer have considered the impact of e-cigarette flavors on cessation outcomes. This study extends previous studies by examining the effects of e-cigarette use and e-cigarette flavors on quit attempts and quit success of smoking. Methods:...

Cigarette smoking continues to pose a threat to public health. Identifying individual risk factors for smoking initiation is essential to further mitigate this epidemic. To our knowledge, no study today has used Machine Learning (ML) techniques to automatically uncover informative predictors of smoking onset among adults using the Population Assess...

Background We model the potential impact of relaxing current nicotine vaping product (NVP) restrictions on public health in Australia. Methods A Restricted NVP Scenario was first developed to project current smoking and vaping rates, where a US smoking model was calibrated to recent Australian trends. To model less restrictive NVP policies, a Perm...

Introduction There is mixed evidence as to whether nicotine vaping products (NVPs) can help adults who smoke transition away from cigarettes. This study investigated if self-reported attempts to quit smoking and smoking cessation, over a period of either 18 or 24 months, differed between respondents who initiated nicotine vaping versus those who di...

Aims: To estimate whether and to what extent extending indoor smoking restrictions to include electronic cigarettes (ECs) impact the use of ECs and cigarette smoking among adults in the US. Design: Observational study using a linear probability model and applying a difference-in-differences analysis SETTING: USA PARTICIPANTS: People aged 18 to 5...

Introduction The cardiovascular health effects of electronic nicotine delivery systems (ENDS) use are not well characterized, making it difficult to assess ENDS as a potential harm reduction tool for adults who use cigarettes. Methods Using waves 1-5 of the Population Assessment of Tobacco & Health Study (2013-2019), we analyzed the risk of self-r...

E-cigarettes are often marketed as a safer alternative to combustible cigarettes. However, their health effects, especially those associated with long-term use, remain largely uncertain. We conducted an umbrella review of the cardiopulmonary and carcinogenic risks of e-cigarette use, distinguishing between short-term and long-term health effects. T...

Background There are limited data on the cost-effectiveness of smoking cessation interventions in lung cancer screening settings. We conducted an economic analysis embedded in a national randomized trial of two telephone counseling cessation interventions. Methods We used a societal perspective to compare the short-term cost per 6-month bio-verifi...

Introduction With the US Food and Drug Administration recently proposing to implement a ban on menthol cigarettes, it is critical to estimate the potential public health effects of such a ban. With high rates of menthol cigarette use and important smoking-related health disparity implications, the impact of the ban on the non-Hispanic black (NHB) p...

Background: In May 2020, the European Union Tobacco Products Directive mandated that EU member states, including Poland, ban the sale of menthol cigarettes. With menthol making up 28% of cigarette sales before the ban, Poland is the country with likely the largest menthol cigarette sales share in the world to ban their sale. We analyze how this ba...

Introduction Definitions of current tobacco and nicotine delivery product use vary and depend on frequency of use, established use criteria, and the product type. Previous research has not considered how transition rates between current use of different products depend on the current use definition. Methods We applied a multistate transition model...

Introduction: Between 2015 and 2018, Canada banned menthol cigarettes. This study pooled data from two pre-post cohort studies (the Ontario Menthol Ban Study, and the International Tobacco Control Policy Evaluation (ITC) Canada Survey, conducted in seven provinces) to derive more precise estimates of the impact of Canada's menthol ban on quitting...

Objectives While many studies have examined the association between e-cigarette use and smoking cessation, fewer have considered the impact of e-cigarette flavors on cessation outcomes. This study extends previous studies by examining the effects of e-cigarette use and e-cigarette flavors on smoking quit attempts and quit success. Methods We used...

Background Understanding the relationship between electronic nicotine delivery systems (ENDS) use and chronic obstructive pulmonary disease (COPD) and other respiratory conditions is critical. However, previous studies have not adequately controlled for history of cigarette smoking. Research Question To examine the prospective association between...

The goal of our study is to understand the impact of Tobacco 21 (T21) laws on youth smoking and health equity. We conducted modified Poisson regression models using 2014-2019 Monitoring the Future data to measure the impact of attending school in a county 100% covered by a T21 law versus counties with <100% T21 coverage on past 30-day smoking parti...

Background Tobacco couponing continues to be part of contemporary tobacco marketing in the US. We performed a systematic review of the evidence of tobacco product coupon receipt and redemption to inform regulation. Methods We searched EMBASE OVID and Medline databases for observational (cross-sectional and longitudinal) studies that examined the p...