Association of Flavored Tobacco Use With Tobacco Initiation and Subsequent Use Among US Youth and Adults, 2013-2015

Key Points Question What is the association between first flavored use of a given tobacco product and subsequent tobacco use, including progression of tobacco use, among US youth (aged 12-17 years), young adults (aged 18-24 years), and adults (aged ≥25 years)? Findings In this cohort study of 11 996 youth and 26 447 adults who participated in waves 1 and 2 of the Population Assessment of Tobacco and Health Study, most youth and young adult new tobacco users first tried a flavored product. First use of flavored tobacco products was positively associated with subsequent product use compared with first use of a nonflavored product. Meaning First use of flavored tobacco products may place youth and adults at risk of subsequent tobacco use.


Introduction
Children prefer sweet flavors more than adults do, 1 and tobacco industry documents [2][3][4][5] confirm that flavors in tobacco products can increase their appeal to young and inexperienced tobacco users.
Consistent with studies [6][7][8] on menthol cigarettes and flavored cigars, data from the first wave of the Population Assessment of Tobacco and Health (PATH) Study [9][10][11] revealed a strong inverse age gradient in the prevalence of flavored tobacco product use, with the highest use among youth aged 12 to 17 years, followed by young adults aged 18 to 24 years, and the lowest use among adults aged 25 years and older.These data 9,10 also show a strong association between first use of a flavored tobacco product and current tobacco use among youth and adults.
Few longitudinal studies to date have examined the association between flavored tobacco product use and initiation or continuation of tobacco use, and these studies [12][13][14] have largely been limited to menthol cigarettes.These studies highlight that menthol brand recognition is associated with smoking experimentation among youth, 12 that adolescents who initiate smoking with menthol cigarettes are more likely to progress to established smoking by the end of 3 years than those who initiated with nonmenthol cigarettes, 13 and that prior initiation with a menthol cigarette compared with a nonmenthol cigarette is associated with current cigarette smoking at follow-up among young adults. 14Five other cross-sectional studies 10,[15][16][17][18] support these findings.
The current study extends prior research by leveraging longitudinal data from waves 1 and 2 of the PATH Study to assess whether there is a prospective association between first flavored use of a given tobacco product and subsequent use of that specific product (eg, e-cigarettes).In addition, this study examines whether first use of a flavored tobacco product at wave 1 is associated with progression to greater frequency of tobacco use at wave 2. The primary aims of this study are to report the proportions of new tobacco users at wave 2 whose first use of a given tobacco product was flavored (ie, first flavored use) and to assess the association between first flavored use of a given tobacco product at wave 1 and subsequent tobacco use, including frequency of tobacco use, at wave 2 for youth (aged 12-17 years), young adults (aged 18-24 years), and adults (aged Ն25 years).

Methods
The National Institutes of Health, through the National Institute on Drug Abuse, is partnering with the adults.An in-person screener was used at wave 1 to select youth and adults from households for participation.
The PATH study was conducted by Westat and approved by the Westat institutional review board.All participants aged 18 years and older provided written informed consent, with youth participants aged 12 to 17 years providing assent while their parent or legal guardian provided written informed consent.This study follows the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) reporting guideline for observational studies. 19pulation and replicate weights using the balanced repeated replication method with the Fay adjustment (ρ = 0.3) were created that adjusted for the complex study design characteristics (eg, oversampling at wave 1) and nonresponse at waves 1 and 2. Combined with the use of a probability sample, the weights allow analyses of the PATH Study data to compute estimates that are robust and representative of the noninstitutionalized, civilian US population aged 12 years and older.The longitudinal sampling weights provided for wave 2 are adjusted for wave 2 nonresponse to ensure that the wave 1 sample is representative of the population in the longitudinal estimates.Further details regarding the PATH Study design and methods have been published elsewhere. 20Details on survey interview procedures, questionnaires, sampling, weighting, and information on accessing the data are available online. 21 wave 1, the weighted response rate for the household screener was 54.0%.Among households that were screened, the overall weighted response rate at wave 1 was 74.0% for the adult interview and 78.4% for the youth interview.At wave 2, the overall weighted response rate was 83.2% for the adult interview and 87.3% for the youth interview.
At wave 1, interviews were completed with 32 320 adults (aged Ն18 years) and 13 651 youth (aged 12-17 years).At wave 2, interviews were completed with 28 362 adults and 12 172 youth.The differences in number of completed interviews between wave 1 and wave 2 reflect attrition due to nonresponse, mortality, and other factors.The sample at wave 2 also includes 1915 youth aged 17 years at wave 1 who responded to the youth questionnaire in wave 1 and then turned 18 and responded to the adult questionnaire in wave 2. 21 Between waves 1 and 2, retention rates were 88.4% for continuing youth, 83.1% for continuing adults, and 85.7% for aged-up adults (

Measures Tobacco Product Use
Ever and current tobacco use was assessed at waves 1 and 2 among youth, young adults, and adults for cigarettes, e-cigarettes, traditional cigars, cigarillos, filtered cigars, hookah tobacco, pipe tobacco, smokeless tobacco (eg, moist snuff or chew), snus pouches, and dissolvable tobacco.Any cigar use was defined as using traditional cigars, cigarillos, or filtered cigars.Any smokeless tobacco use was defined as using smokeless tobacco or snus pouches.Youth, young adults, and adults who tried a tobacco product for the first time between waves 1 and 2 were defined as new users, with age at tobacco trial defined as their age at wave 1.Current use was defined in multiple ways as outlined in previous analyses 22 and in the eTable in the Supplement.Participants missing data on moderate, frequent, or daily use of a product because of an instrument skip pattern were coded as not having the outcome and were included in the denominator.

Wave 1 First Flavored Tobacco Product Use
At wave 1, ever cigarette users were asked whether, when they first used a cigarette (youth) or when they first started smoking cigarettes (adults), it was "flavored to taste like menthol or mint."Ever cigarette users who replied "no" to the menthol question were then asked whether their first users of other tobacco products were queried about whether, when they first used the product (youth) or when they first started using the product (adults), it was "flavored to taste like menthol, mint, clove, spice, candy, fruit, chocolate, alcohol (such as wine or cognac), or other sweets" (eTable in the Supplement).

Wave 1 Covariates
All covariates were assessed at wave 1 and were selected on the basis of previous work 10

Statistical Analysis
Data analysis was conducted from July 2016 to June 2019.Analyses were conducted using svy procedures in Stata/SE statistical software version 14.2 (StataCorp) to account for the complex study design.Analysis of new users focused on the prevalence of using a flavored product at first tobacco use at wave 2 (Figure).For all other analyses, the main outcome was current product-specific use at wave 2 as defined in the eTable in the Supplement.The prevalence of each outcome was estimated for youth, young adults, and adults aged 25 years and older according to age at wave 1. Estimates with denominators less than 50 or relative SE greater than 30% were suppressed. 24Missing data on age, sex, race or Hispanic ethnicity, and adult education were imputed at wave 1 as described elsewhere. 21Participants missing any response to a composite variable (eg, any past 30-day tobacco use) were treated as missing; missing data were handled with listwise deletion.Multivariable models were built separately for youth, young adults, and adults aged 25 years or older; all models included sex, race/ethnicity, education, past 30-day alcohol, marijuana, or other drug use, and the 3 Global Appraisal of Individual Needs-Short Screener subscales as covariates.Adult models also included age and income.Modified Poisson regression models 25 estimated the association between first flavored tobacco use among ever users at wave 1 and current tobacco use at wave 2, as well as moderate, frequent, and daily use at wave 2. For the 3 products for which there were sufficient sample sizes in each of the age groups (flavored cigarettes, menthol cigarettes, and flavored e-cigarettes), we conducted multivariable multinomial logistic regression models of increasing frequency of tobacco use compared with no use from the mutually exclusive categories of tobacco use frequency.For all analyses, α was set at P < .05using 2-sided tests.Stata's svy commands used a logit transformation to produce confidence intervals with limits between 0 and 1. 26

Results
The mean (SE) age of the participants at wave 2 was 14.5 (0.0) years for youth, 21.1 (0.0) years for young adults, and 50.Percentages are weighted to represent the US population, and 95% CIs (whiskers) are estimated using the balanced repeated replication method.New use is ascribed to the participants' age at wave 1. Respondents were categorized into age groups (youth aged 12-17 years, young adults aged 18-24 years, and adults aged Ն25 years) according to their ages at wave 1.New use of a tobacco product is defined as starting to use a product between waves 1 and 2. This can include never users at wave 1 who start tobacco use at wave 2 and ever users at wave 1 who report use of a new product or products at wave 2. Individuals who reported "don't know" or refused to answer any part of the definition of ever use or first flavored use were excluded from the denominator.Unweighted numbers and unweighted percentages are presented for each age group: Among 11 996 youth, 2136 (17.8%) reported new use of a tobacco product, 9622 (80.2%) reported no new initiation, and 238 (2.0%) did not provide information on initiation between wave 1 and wave 2. Among 7325 young adults, 2058 (24.9%) reported new use of a tobacco product, 5232 (74.7%) reported no new initiation, and 35 (0.4%) did not provide information on initiation between wave 1 and wave 2. Among 19 116 adults aged 25 years and older, 2580 (8.1%) reported new use of a tobacco product, 16 407 (91.4%) reported no new initiation, and 129 (0.5%) did not provide information on initiation between wave 1 and wave 2. First flavored use is defined as reporting that the first product used was "flavored to taste like menthol, mint, clove, spice, candy, fruit, chocolate, alcohol (such as wine or cognac), or other sweets."Individuals who did not report "yes," "no," or "I don't know" or refused to answer whether their first product was flavored were excluded from the denominator.Flavored pipe tobacco and dissolvable tobacco use was not assessed among youth.Unweighted numbers and unweighted percentages are presented for each age group.For 2136 youth new tobacco users, 95 (4.5%) did not report whether they had used any flavored product between wave 1 and wave 2. For 2058 young adult new tobacco users, 58 (2.8%) did not report whether they had used any flavored product between wave 1 and wave 2. For 2580 adult (aged Ն25 years) new tobacco users, 58 (2.3%) did not report whether they had used any flavored product between wave 1 and wave 2. Any tobacco product included cigarettes, e-cigarettes, traditional cigars, cigarillos, filtered cigars, hookah, pipe (for adults only), smokeless tobacco, and snus or dissolvable tobacco (for adults only); any cigar use reflects use of a traditional cigar, cigarillo, or filtered cigar.Data are from the Population Assessment of Tobacco and Health (PATH) Study, [9][10][11] Abbreviations: aPR, adjusted prevalence ratio; NA, not applicable.
c Moderate use was defined as having smoked or used the product on at least 6 of the past 30 days.Frequent product use was defined as having smoked or used the product on at least 20 of the past 30 days.Daily use among youth was defined as having smoked or used the product on 30 of the past 30 days.Individuals who responded "don't know" or refused to answer were excluded from the denominator.Unweighted numbers (percentages) of respondents excluded from the denominator for moderate, frequent, and daily use were as follows: cigarettes moderate or frequent use, 25  Abbreviations: aPR, adjusted prevalence ratio; NA, not applicable.
c Moderate use was defined as having smoked or used the product on at least 6 of the past 30 days.Frequent product use defined as having smoked or used the product on at least 20 of the past 30 days.Individuals who responded "don't know" or refused to answer were excluded from the denominator.Unweighted numbers (percentages) of respondents excluded from the denominator for moderate and frequent use were as follows:  Abbreviations: aPR, adjusted prevalence ratio; NA, not applicable.
c Moderate use was defined as having smoked or used the product on at least 6 of the past 30 days.Frequent product use was defined as having smoked or used the product on at least 20 of the past 30 days.Individuals who responded "don't know" or refused to answer were excluded from the denominator.Unweighted numbers (percentages) of respondents excluded from the denominator for moderate and frequent use were as follows: cigarettes

Discussion
The current study found that (1) youth and young adults who were new users of a tobacco product at wave 2 (over the 10-to 13-month follow-up period) were more likely to try flavored tobacco products than adults; (2) first use of a flavored cigarette documented at wave 1 was positively associated with past 12-month and past 30-day cigarette use among youth, young adults, and adults aged 25 years and older at wave 2; (3) first use of a menthol or mint flavored cigarette documented at wave 1 was positively associated with past 12-month and past 30-day cigarette use at wave 2 in all age groups; (4) first use of flavored e-cigarettes, cigars, hookah, and smokeless tobacco was associated with subsequent use of those products at wave 2 among young adults and adults aged 25 years and older; (5) first flavored use of a cigarette, e-cigarette, any cigar, cigarillo, filtered cigar, hookah, and any

US
Food and Drug Administration's Center for Tobacco Products to conduct the PATH Study under a contract with Westat.The PATH Study is an ongoing, nationally representative, longitudinal cohort study of adults and youth in the United States.The PATH Study uses audio computer-assisted selfinterviews available in English and Spanish to collect self-reported information on tobacco-use patterns and associated health behaviors.Wave 1 data collection was conducted from September 12, 2013, to December 14, 2014; wave 2 data were collected from October 23, 2014, to October 30, 2015.The PATH Study recruitment used a stratified, address-based, area-probability sampling design at wave 1 that oversampled adult tobacco users, young adults (aged 18-24 years), and African American JAMA Network Open | Public Health Association of Flavored Tobacco Use With Tobacco Initiation and Subsequent Use JAMA Network Open.2019;2(10):e1913804. doi:10.1001/jamanetworkopen.2019.13804(Reprinted) October 23, 2019 2/17 Downloaded From: https://jamanetwork.com/ on 09/16/2023

Table 1 .
Association Between First Tobacco Product Flavored Among Youth Ever Tobacco Users at Wave 1 and Product-Specific Tobacco Use at Wave 2 of the Population Assessment of Tobacco and Health Study (continued)

Table 2 .
Poisson regression models among youth were adjusted for sex, race/ethnicity, education, past 30-day alcohol, marijuana, or other drug use, and 3 Global Appraisal of Individual Needs-Short Screener subscales (internalizing problems, externalizing problems, and substance use problems).Individuals who reported "don't know" or refused to answer any of these items were treated as missing.Among youth ever tobacco users, data were missing for sex (0 participants [0.0%]), race/ethnicity (0 participants [0.0%]), education (128 participants [5.2%]), past 30-day alcohol, marijuana, or other drug use (64 participants [2.6%]), internalizing problems subscale (52 participants [2.1%]), externalizing problems subscale (93 participants [3.8%]), and substance use problems subscale (91 participants [3.7%]).Respondents who reported never alcohol, marijuana, or other drug use were categorized as non-past 30-day users.was made between wave 1 cigarette smokers who first smoked a menthol or mint flavored cigarette vs smokers who first smoked a nonflavored cigarette.Individuals who reported first other flavored cigarette use were excluded from the denominator.suppressed because it has low statistical precision.It is based on a sample size of less than 50, or the coefficient of variation of the estimate is larger than 30%.Association of Flavored Tobacco Use With Tobacco Initiation and Subsequent Use Association Between First Tobacco Product Flavored Among Young Adult Ever Tobacco Users at Wave 1 and Product-Specific Tobacco Use at Wave 2 of the Population Assessment of Tobacco and Health Study d Multivariable modified e A separate comparison f The estimate was g There were insufficient observations to compute balanced repeated replication SEs.h Any smokeless tobacco use was defined as smokeless and/or snus use.JAMA Network Open | Public Health JAMA Network Open.2019;2(10):e1913804. doi:10.1001/jamanetworkopen.2019.13804(Reprinted) October 23, 2019 7/17 Downloaded From: https://jamanetwork.com/ on 09/16/2023 JAMA Network Open.2019;2(10):e1913804. doi:10.1001/jamanetworkopen.2019.13804(Reprinted) October 23, 2019 8/17 Downloaded From: https://jamanetwork.com/ on 09/16/2023

Table 2 .
Association Between First Tobacco Product Flavored Among Young Adult Ever Tobacco Users at Wave 1 and Product-Specific Tobacco Use at Wave 2 of the Population Assessment of Tobacco and Health Study (continued) Poisson regression models among young adults were adjusted for age, sex, race/ethnicity, education, income, past 30-day alcohol, marijuana, or other drug use, and 3 Global Appraisal of Individual Needs-Short Screener subscales (internalizing problems, externalizing problems, and substance use problems).Individuals who reported "don't know" or refused to answer any of these items were treated as missing.Among was made between wave 1 cigarette smokers who first smoked a menthol or mint flavored cigarette vs smokers who first smoked a nonflavored cigarette.Individuals who reported first other flavored cigarette use were excluded from the denominator.suppressed because it has low statistical precision.It is based on a sample size of less than 50, or the coefficient of variation of the estimate is larger than 30%.
d Daily use among adults was defined as now smokes or uses product every day.Current regular use was defined for cigarettes as having smoked at least 100 cigarettes in lifetime and now smokes every day or some days; for all other products, regular use was defined as having ever used a product "fairly regularly" and now uses it every day or some days.Individuals who responded "don't know" or refused to answer were excluded from the e Multivariable modified f A separate comparison g The estimate was h There was insufficient observations to compute balanced repeated replication SEs.i Any smokeless tobacco use was defined as smokeless and/or snus use.

Table 3 .
Association Between First Tobacco Product Flavored Among Adults Aged 25 Years and Older Ever Tobacco Users at Wave 1 and Product-Specific Tobacco Use at Wave 2 of the Population Assessment of Tobacco and Health Study Association of Flavored Tobacco Use With Tobacco Initiation and Subsequent Use JAMA Network Open.2019;2(10):e1913804. doi:10.1001/jamanetworkopen.2019.13804(Reprinted) October 23, 2019 10/17 Downloaded From: https://jamanetwork.com/ on 09/16/2023

Table 3 .
Association Between First Tobacco Product Flavored Among Adults Aged 25 Years and Older Ever Tobacco Users at Wave 1 and Product-Specific Tobacco Use at Wave 2 of the Population Assessment of Tobacco and Health Study (continued)

Table 4 .
Multivariable Multinomial Logistic Regression Models of Frequency of Use at Wave 2 Among Ever Users of Specified Product at Wave 1 of the Population Assessment of Tobacco and Health Study, by Age Group