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RESEARCH ARTICLE

Adolescents’ first tobacco products:

Associations with current multiple tobacco

product use

Sarah D. KowittID 1*, Adam O. Goldstein1,2☯, Erin L. Sutfin3☯, Amira Osman1,4☯,

Clare Meernik 5☯

, Courtney Heck 6☯

, Leah M. Ranney 1☯

1 Department of Family Medicine, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill,

NC, United States of America, 2 Lineberger Comprehensive Cancer Center, Chapel Hill, NC, United States of

America, 3 Department of Social Sciences and Health Policy, Wake Forest School of Medicine, Winston-

Salem, NC, United States of America, 4 School of Nursing, Zefat Academic College, Zefat, Israel,

5 Department of Epidemiology, Gillings School of Global Public Health, University of North Carolina at Chapel

Hill, Chapel Hill, NC, United States of America, 6 North Carolina Department of Health and Human Services,

Tobacco Prevention and Control Branch, Raleigh, NC, United States of America

☯ These authors contributed equally to this work. * [email protected]

Abstract

Understanding which tobacco products adolescents use first can lead to insights for tobacco

prevention interventions and policies. We used cross-sectional data from high school stu-

dents who reported ever using a tobacco product from the 2017 North Carolina Youth

Tobacco Survey (n = 1,053). In multivariable regressions, we examined how demographic

and psychosocial factors were associated with adolescents’ first product tried and how first

product tried was associated with current tobacco use (i.e., no use, use of a single product,

use of multiple products) and frequency of tobacco use. Cigarettes (34.8%) and e-cigarettes

(33.7%) were the most frequently reported first products tried, followed by cigars (15.6%),

smokeless tobacco (10.7%), waterpipe (4.0%), and other tobacco products (i.e., pipe

tobacco or some other tobacco product) (1.2%). Demographic differences in adolescents’

first product tried existed, with Black adolescents having higher odds of initiating tobacco

use via cigars (aOR: 6.17, 95% CI: 3.75, 10.14). Adolescents who initiated tobacco use via

cigars (aOR: 2.33, 95% CI: 1.31, 4.13) or smokeless tobacco (aOR: 2.45, 95% CI: 1.18,

5.04) had higher odds of being a multiple current tobacco product user, whereas adoles-

cents who initiated tobacco use via e-cigarettes (aOR: 0.57, 95% CI: 0.34, 0.93) had lower

odds of being a multiple current tobacco product user. Additionally, adolescents who initi-

ated tobacco use via smokeless tobacco had higher odds of currently using at least one

tobacco product frequently (aOR: 1.90, 95% CI: 1.04, 3.48), while adolescents who initiated

tobacco use via e-cigarettes had lower odds of currently using at least one tobacco product

frequently (aOR: 0.40, 95% CI: 0.23, 0.70). These findings suggest that most adolescents

reported initiating tobacco use via cigarettes or e-cigarettes and that trying certain products

first (e.g., cigars, smokeless tobacco) was associated with higher odds of multiple current

tobacco product use.

PLOS ONE | https://doi.org/10.1371/journal.pone.0217244 May 23, 2019 1 / 16

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OPEN ACCESS

Citation: Kowitt SD, Goldstein AO, Sutfin EL,

Osman A, Meernik C, Heck C, et al. (2019)

Adolescents’ first tobacco products: Associations

with current multiple tobacco product use. PLoS

ONE 14(5): e0217244. https://doi.org/10.1371/

journal.pone.0217244

Editor: Michael Cummings, Medical University of

South Carolina, UNITED STATES

Received: January 29, 2019

Accepted: May 7, 2019

Published: May 23, 2019

Copyright: © 2019 Kowitt et al. This is an open access article distributed under the terms of the

Creative Commons Attribution License, which

permits unrestricted use, distribution, and

reproduction in any medium, provided the original

author and source are credited.

Data Availability Statement: All relevant data are

within the manuscript and its Supporting

Information files.

Funding: Grant number P50 CA180907 from the

National Cancer Institute and the FDA Center for

Tobacco Products (CTP) supported the authors’

time spent writing the paper. The content is solely

the responsibility of the authors and does not

necessarily represent the official views of the NIH

or the Food and Drug Administration. Data

collection for this article was supported by the

Introduction

Over the last decade, the tobacco product landscape has changed markedly. Given these

changes, data on how adolescents initiate tobacco use (i.e., which products they try first and

demographic factors associated with first products tried) is needed. These data are important

for several reasons. First, all tobacco products contain nicotine, which is highly addictive. Nic-

otine causes harm to adolescents’ developing brains and can lead to future tobacco use [1]. To

prevent adolescents’ exposure to nicotine and tobacco products, we need to know how adoles-

cents are initiating tobacco use (i.e., which products they are trying first). Second, in order to

effectively prevent tobacco product use, we need to know how demographic factors are associ-

ated with which products adolescents try first. For instance, if Black adolescents are typically

only trying cigars first, then interventions to prevent cigar use can be tailored to Black adoles-

cents. Finally, if data indicate that trying certain products first (e.g., cigarettes) is associated

with adolescents currently using multiple tobacco products, then tobacco prevention interven-

tions and policies can be targeted toward those products.

While historically tobacco use has begun with cigarettes [2–4], recent data suggest that the

landscape for tobacco product initiation may be changing. One paper, using national data

from 2014–2015, found that 18.6% of adolescents reported ever trying a tobacco product, and

while cigarettes were the most frequently reported first product tried, sizeable proportions of

adolescents reported trying e-cigarettes or smokeless tobacco (SLT) first [5]. This study also

found demographic differences in first product tried. Specifically, females (relative to males)

and Hispanic adolescents (relative to non-Hispanic adolescents) were more likely to initiate

tobacco use via cigarettes; White adolescents (relative to non-White adolescents) were more

likely to initiate tobacco use via SLT; and adolescents of higher socioeconomic status (SES)

were more likely to initiate tobacco use via waterpipe (relative to those of lower SES) [5].

Three other studies have examined adolescents’ first products tried [6–8] but only examined

certain tobacco products (i.e., cigars and cigarettes with data from 2003–2004 [7]); only exam-

ined first product tried in a limited sample (i.e., adolescent lifetime e-cigarette users in Con-

necticut [6]); or examined first product tried in a sample of both adolescents and young adults,

but did not differentiate results by age group [8].

Further, it is important to examine whether trying certain products first is associated with

higher risk of multiple tobacco product use (i.e., concurrent use of two or more tobacco products)

and higher risk of using tobacco products frequently. Over two million adolescents, almost half of

adolescent tobacco users, are multiple tobacco product users [9]. Multiple tobacco product use is

concerning because it is associated with increased symptoms of nicotine dependence [10], ele-

vated risk of health concerns (e.g., myocardial infarction) [11], and decreased likelihood of suc-

cessful quitting [12, 13]. While certain demographic and psychosocial factors are associated with

increased risk for multiple tobacco product use (e.g., being male, having a higher propensity for

sensation-seeking, having tried tobacco at a younger age) [8], little research has examined if trying certain tobacco products first is associated with multiple tobacco product use. If research shows

that initiating tobacco product use via certain products is associated with greater risk of multiple

tobacco product use, then interventions can be targeted toward those specific products. Although

some research has shown that initiating e-cigarette use is associated with future tobacco use [14–

18], research has not differentiated whether trying certain tobacco products first (relative to other

tobacco products) is associated with current multiple tobacco use. To our knowledge, no studies

have examined how first product tried is associated with past 30 day (current) multiple tobacco

product use or with frequency of tobacco product use in the past 30 days.

Our study had three aims: 1) examine how demographic and psychosocial factors are asso-

ciated with which tobacco products adolescents try first; 2) examine how first product tried is

Adolescents’ first tobacco products

PLOS ONE | https://doi.org/10.1371/journal.pone.0217244 May 23, 2019 2 / 16

grant or cooperative agreement no. DP005974

funded by the Centers for Disease Control and

Prevention. Its contents are solely the

responsibility of the authors and do not necessarily

represent the official views of the Centers for

Disease Control and Prevention or the US

Department of Health and Human Services.

Competing interests: The authors have declared

that no competing interests exist.

associated with current tobacco product use (e.g., no use, single tobacco product use, multiple

tobacco product use); and 3) examine how first product tried is associated with frequency of

tobacco product use (e.g., frequent or non-frequent tobacco product use). We hypothesized,

given recent data in rising prevalence of e-cigarettes [19], that many adolescents would report

trying e-cigarettes first. Consistent with previous research [5], we also hypothesized that demo-

graphic and psychosocial factors would be associated with which products adolescents try first.

Finally, given a lack of previous research, we had no a priori hypotheses on whether or not try-

ing certain products first would be associated with current tobacco product use or frequency

of tobacco product use.

Methods

Participants and procedures

We used data from the 2017 North Carolina Youth Tobacco Survey (NCYTS). The NCYTS is

a public and charter school-based survey of students in grades 6–12 and designed to provide

data on tobacco use and progress toward overall goals among youth. A multi-stage cluster

sampling design in three distinct regions of the state was used. School districts were first

selected within three geographic regions of the state; a school’s probability for selection was

proportional to its enrollment size for the survey year. Classes were then randomly selected

within each school. Participation was voluntary and anonymous. Passive consent forms were

utilized, unless an active consent form was required according to a specific school district pol-

icy. We focused our analyses on high school students given low rates of tobacco use among

middle school students. The overall response rate was 64.5% for high school students (75.2%

school response rate; 85.8% student response rate). With regard to ethical approval, our study

used secondary, de-identified data and did not constitute human subjects research as defined

under federal regulations 45 CFR 46.102 (d or f) and 21 CFR 56.102(c)(e)(l); hence, this study

did not require Institutional Review Board approval.

Measures

All measures described below can be seen in the 2017 NCYTS questionnaire, which is pub-

lished online and accessible using this website: https://www.tobaccopreventionandcontrol.

ncdhhs.gov/data/yts/docs/2017-NC-YTS-Questionnaire-FINAL.pdf.

First tobacco product tried. Our main outcome of interest was first tobacco product

tried, which the survey assessed by asking participants, “Which of the following tobacco prod-

ucts did you try first (choose only one answer).” Responses included: 1) cigarettes, 2) cigars

(including little cigars and cigarillos), 3) tobacco in a hookah or a waterpipe, 4) pipe tobacco,

5) electronic cigarettes, 6) chewing tobacco, snuff, or dip, 7) snus, and 8) dissolvable tobacco,

9) some other tobacco product, 10) not sure about the product I tried first, and 11) I have

never tried any tobacco products. We removed participants who responded that they were not

sure about the product that they tried first or reported never trying any tobacco products.

We collapsed responses of chewing tobacco, snuff, dip, snus, and dissolvable tobacco into

one category and labeled it SLT. Due to small sample sizes, we also collapsed responses of pipe

tobacco and “some other tobacco product” into one category and labeled it “other tobacco

products” (OTPs).

Current multiple tobacco product use. Our second outcome of interest was current mul-

tiple tobacco product use. The survey assessed past 30 days use of nine tobacco products,

including those mentioned above and bidis. Adolescents were then classified as 1) non-current

tobacco product users if they did not use any tobacco product within the past 30 days, 2) single

current tobacco product users if they used only one tobacco product within the past 30 days,

Adolescents’ first tobacco products

PLOS ONE | https://doi.org/10.1371/journal.pone.0217244 May 23, 2019 3 / 16

and 3) multiple current tobacco product users if they indicated using two or more tobacco

products within the past 30 days.

Frequency of tobacco product use. Our third outcome of interest was frequency of

tobacco product use among current users. The survey assessed frequency of tobacco use of five

different tobacco products: cigarettes, cigars, e-cigarettes, SLT, and waterpipe. The question

stem was “During the past 30 days, on how many days did you smoke. . .? Responses included

“0 days,” “1 or 2 days,” “3 to 5 days,” “6 to 9 days,” “10–19 days,” “20 to 29 days,” and “all 30

days.” In line with previous research [20], if participants chose “20 to 29 days” or “all 30 days,”

they were coded as frequent users. Otherwise, participants were coded as non-frequent users if

they chose any other response option.

Psychosocial variables. Psychosocial variables included: exposure to tobacco advertising

via the Internet and retail locations, perceived risks of tobacco use, exposure to secondhand

smoke, and living with tobacco product users. The survey assessed exposure to tobacco advertis-

ing via the Internet by asking participants, “When you are using the Internet, how often do you

see ads for tobacco products, including electronic cigarettes?” In line with previous research

[21], we dichotomized exposure as “yes” for responses “always,” “most of the time,” and “some-

times” and “no” for “I do not use the Internet,” “never,” and “rarely.” The survey assessed expo-

sure to tobacco advertising via retail locations by asking participants, “When you go to a

convenience store, supermarket, or gas station, how often do you see ads for tobacco products,

including electronic cigarettes?” We dichotomized exposure to tobacco advertising via retail

locations in the same way as we dichotomized exposure to tobacco advertising via the Internet.

The survey assessed perceived risks of tobacco use by asking participants two questions.

First, participants were asked, “How strongly do you agree with the statement ‘All tobacco

products are dangerous’?” In line with previous research [21], we dichotomized perceived risk

as “yes” for the response “strongly agree” and “no” for the responses “agree,” “disagree,” and

“strongly disagree.” Second, participants were asked, “Do you think that breathing smoke

from other people’s cigarettes or other tobacco products is . . .” We dichotomized perceived

risk as “yes” for the response “very harmful to one’s health” and “no” for the responses “some-

what harmful to one’s health,” “not very harmful to one’s health,” and “not harmful at all to

one’s health.”

The survey assessed secondhand smoke exposure by asking participants, “During the past 7

days, on how many days did you breathe the smoke from someone who was smoking tobacco

products in an indoor or outdoor public place? Examples of indoor public places are school

buildings, stores, restaurants, and sports arenas. Examples of outdoor public places are school

grounds, parking lots, stadiums and parks.” We dichotomized exposure as “yes” for the

responses “1 day,” “2 days,” “3 days,” “4 days,” “5 days,” or “6 days” and “no for the response

“0 days.”

The survey assessed living with a tobacco user by asking participants, “Does anyone who

live with you now. . .” Response options included, “smoke cigarettes,” “smoke cigars, cigarillos,

or little cigars,” “use chewing tobacco, snuff, or dip,” “use e-cigarettes,” “smoke tobacco in a

hookah or waterpipe,” “smoke pipes filled with tobacco (not waterpipe),” “use snus,” “use dis-

solvable tobacco products,” “smoke bidis,” and “no one who lives with me now uses any form

of tobacco.” We dichotomized living with a tobacco user as “yes” if participants chose any of

the 9 listed tobacco products and “no” if participants chose “no one who lives with me now

uses any form of tobacco.”

Demographics. Demographic variables included sex (female or male), grade (9 th

, 10 th

,

11 th

, or 12 th

), race/ethnicity (non-Hispanic White, non-Hispanic Black, Hispanic, or non-His-

panic other race), and adolescent socioeconomic status (SES). We measured adolescent SES by

asking, “Do you get free or reduced-price lunch at school?” (yes or no) [22].

Adolescents’ first tobacco products

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Study analytic sample

Since we were interested in what factors were associated with adolescents’ first product tried, we

restricted analyses to adolescents who had ever tried one of the nine listed tobacco products

(“ever tobacco product users”). Of the 3,133 high school students in the 2017 NCYTS, we

dropped participants who had never tried a tobacco product (n = 1,528), did not report their first

product tried (n = 422), or who had missing data on any of the other study variables (n = 163),

resulting in a final analytic sample of 1,020 participants (see S1 Table for an attrition analysis).

Data analysis

To answer our first research question, we examined demographic and psychosocial correlates

of first product tried using bivariate logistic regressions. Given the number of demographic

and psychosocial correlates we were examining, we only entered correlates that were statisti-

cally significant (p <0.10) into a multivariable logistic regression model. For each tobacco

product, adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for using that prod-

uct first versus any of the other tobacco products are presented.

To answer our second research question (whether first product tried is associated with cur-

rent tobacco use), we examined which products adolescents were currently using by calculat-

ing weighted percentages of current tobacco product use stratified by first product tried. We

then used a multivariable, multinomial logistic regression model and controlled for demo-

graphic correlates. Although our outcome, current tobacco use, was ordinal in nature, we spec-

ified a multinomial model with non-current tobacco users as the reference category because 1)

the proportional odds assumption failed, which indicates that the effects of the covariates

across the current tobacco use categories are not the same [23] and 2) it was of interest to com-

pare multiple current tobacco product users to non-current tobacco product users and single

current tobacco product users to non-current tobacco product users which has been done in

previous studies [24]. Finally,

To answer our third research question (whether first product tried is associated with fre-

quency of tobacco use among current users of any tobacco product), we used bivariate logistic

regressions and a multivariable logistic regression model that controlled for demographic cor-

relates. The outcome was whether participants frequently used any tobacco product vs.

whether participants did not frequently use any tobacco products. All analyses used SAS ver-

sion 9.4 survey procedures (SAS Inc., Cary, NC, USA). We set critical α = .05 (except as noted above) and used 2-tailed statistical tests.

Results

Participant characteristics

Among the 1,020 participants who reported ever tobacco product use, the majority identified

as non-Hispanic White (64.0%) and almost half reported receiving free or reduced-price lunch

(45.9%) (see Table 1). In this sample of ever tobacco product users, almost two-thirds (64.6%)

reported they currently used a tobacco product, with 34.1% classified as single tobacco prod-

ucts users and 30.5% classified as multiple tobacco product users. Among current users of any

tobacco product, 26.9% reported frequently using at least one tobacco product, with the

remainder reporting non-frequent use (73.1%).

Almost as many adolescents reported e-cigarettes (33.7%) were their first tobacco product

tried as adolescents who reported cigarettes (34.8%) were their first tobacco product tried (Fig

1). This was followed by cigars (15.6%), SLT (10.7%), waterpipe (4.0%), and OTPs (including

pipe tobacco and other products not listed, 1.2%).

Adolescents’ first tobacco products

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Research Question 1—Bivariate results: Demographics and first product tried

Sex, race, free or reduced-price lunch, exposure to tobacco advertising via the Internet, per-

ceived risk of tobacco use (‘all tobacco products are dangerous’), secondhand smoke exposure,

Table 1. Characteristics of ever tobacco product users, n = 1020, North Carolina Youth Tobacco Survey, 2017.

Characteristic Total n (%)

Sex

Female 492 (49.2)

Male 528 (50.8)

Grade

9 th

253 (20.4)

10 th

261 (25.9)

11 th

211 (26.2)

12 th

295 (27.4)

Race

Non-Hispanic White 612 (64.0)

Non-Hispanic Black 190 (17.9)

Hispanic 163 (11.0)

Non-Hispanic other race 55 (7.1)

Free or reduced-price lunch

Yes 496 (45.9)

No 524 (54.1)

Exposure to tobacco advertising via the Internet

No 514 (50.8)

Yes 506 (49.2)

Exposure to tobacco advertising via retail locations

No 177 (15.9)

Yes 843 (84.1)

Perceived risk: Agreed that “all tobacco products are dangerous”

No 664 (65.3)

Yes 356 (34.7)

Perceived risk: Agreed that “breathing smoke from other people’s cigarettes or other tobacco products

is harmful”

No 541 (57.2)

Yes 479 (42.8)

Exposed to secondhand smoke exposure

No 525 (50.7)

Yes 495 (49.3)

Living with a tobacco product user

No 422 (39.8)

Yes 598 (60.2)

Current multiple tobacco product use�

No current use 380 (35.4)

Current single product use 312 (34.1)

Current multiple product use 328 (30.5)

Frequency of any tobacco product use among current users of any tobacco product

Non-frequent 450 (73.1)

Frequent 187 (26.9)

� When collapsed, 64.6% of the sample was classified as a current tobacco product user.

https://doi.org/10.1371/journal.pone.0217244.t001

Adolescents’ first tobacco products

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and living with a tobacco product user were all associated with first product tried (p < 0.10),

while grade, exposure to tobacco advertising via retail locations, and perceived risk of tobacco

use (‘breathing smoke from other people’s cigarettes or other tobacco products is harmful’)

were not significantly associated with first product tried. See S2 Table for full results from the

bivariate analyses.

Research Question 1—Multivariable logistic regression results:

Demographics and first product tried

Males versus females. Males, relative to females, had lower odds of initiating tobacco

use via cigarettes (aOR: 0.62, 95% CI: 0.42, 0.92) and e-cigarettes (aOR: 0.54, 95% CI: 0.41,

0.71), but greater odds of initiating tobacco use via SLT (aOR: 10.29, 95% CI: 4.02, 26.31)

(Table 2).

Race / Ethnicity. Non-Hispanic Black adolescents, relative to non-Hispanic White adoles-

cents had lower odds of initiating tobacco product use via cigarettes (aOR: 0.55, 95% CI: 0.33,

0.91), e-cigarettes (aOR: 0.52, 95% CI: 0.32, 0.83), and SLT (aOR: 0.14, 95% CI: 0.04, 0.44), but

greater odds of initiating tobacco product use via cigars (aOR: 6.17, 95% CI: 3.75, 10.14). In

addition, Hispanic adolescents, relative to non-Hispanic White adolescents, had lower odds of

initiating tobacco use via SLT (aOR: 0.41, 95% CI: 0.18, 0.92), but greater odds of initiating

tobacco product use via waterpipe (aOR: 3.46, 95% CI: 1.38, 8.68).

Free or reduced-price lunch. Adolescents on free or reduced-price lunch, relative to

those not on free or reduced-price lunch, had lower odds of initiating tobacco product use via

e-cigarettes (aOR: 0.39, 95% CI: 0.27, 0.58) but greater odds of initiating tobacco product use

via cigarettes (aOR: 2.36, 95% CI: 1.39, 4.01).

Tobacco advertising via the Internet. Adolescents who were exposed to tobacco advertis-

ing via the Internet, relative to those not exposed, had lower odds of initiating tobacco product

use via cigars (aOR: 0.57, 95% CI: 0.36, 0.99) but greater odds of initiating tobacco product use

via e-cigarettes (aOR: 1.28, 95% CI: 1.00, 1.65).

Fig 1. Prevalence of first product tried among ever tobacco product users, n = 1020, North Carolina Youth Tobacco Survey, 2017 Abbreviations:

Smokeless tobacco (SLT); Other tobacco products (OTPs), which refers to pipe tobacco or some other tobacco product not listed.

https://doi.org/10.1371/journal.pone.0217244.g001

Adolescents’ first tobacco products

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Perceived risk of tobacco products. Adolescents who agreed that all tobacco products are

dangerous, relative to those who did not agree, had lower odds of initiating tobacco product

use via cigars (aOR: 0.62, 95% CI: 0.39, 0.99) but greater odds of initiating tobacco product use

via cigarettes (aOR: 1.64, 95% CI: 1.13, 2.38).

Secondhand smoke exposure. Adolescents who were exposed to secondhand smoke, rel-

ative to those who were not exposed, had lower odds of initiating tobacco product use via e-

cigarettes (aOR: 0.54, 95% CI: 0.40, 0.75) but greater odds of initiating tobacco product use via

SLT (aOR: 2.71, 95% CI: 1.60, 4.59).

Living with a tobacco product user. Adolescents who lived with a tobacco product user,

relative to those who did not, had lower odds of initiating tobacco product use via e-cigarettes

(aOR: 0.54, 95% CI: 0.41, 0.71) but greater odds of initiating tobacco product use via cigarettes

(aOR: 1.94, 95% CI: 1.38, 2.71).

Research Question 2—Bivariate results: First product tried and current

tobacco product use

To answer our second research question, we descriptively examined what products adolescents

were currently using and stratified results by first product tried (Table 3). In the total sample,

64.6% of adolescents who reported ever trying a tobacco product reported past 30 days use of a

tobacco product, with prevalence estimates ranging from 36.7% to 80.4% for each product. In

addition, between 14.9% and 50.2% of adolescents first trying any tobacco product currently

used multiple tobacco products. The prevalence of current multiple tobacco product use was

lowest for adolescents who reported first trying waterpipe (14.9%) and highest for adolescents

who reported first trying SLT (50.2%).

Table 2. Adjusted logistic regression results—Demographics and first product tried, among ever tobacco users, n = 1020, North Carolina Youth Tobacco Survey,

2017.

First tried

cigarettes vs. all

other products

First tried e-

cigarettes vs. all

other products

First tried cigars

vs. all other

products

First tried SLT

vs. all other

products

First tried

waterpipe vs. all

other products

First tried OTPs (pipe

tobacco, other) vs. all

other products

aOR (95% CI) aOR (95% CI) aOR (95% CI) aOR (95% CI) aOR (95% CI) aOR (95% CI)

Male (ref = female) 0.62 (0.42, 0.92) 0.54 (0.41, 0.71) 1.58 (0.96, 2.60) 10.29 (4.02,

26.31)

1.28 (0.37, 4.36) 0.42 (0.11, 1.65)

Non-Hispanic Black

(ref = non-Hispanic White)

0.55 (0.33, 0.91) 0.52 (0.32, 0.83) 6.17 (3.75, 10.14) 0.14 (0.04, 0.44) 2.57 (0.90, 7.39) 1.43 (0.35, 5.93)

Hispanic (ref = non-Hispanic

White)

0.89 (0.63, 1.27) 1.18 (0.79, 1.77) 1.04 (0.55, 1.97) 0.41 (0.18, 0.92) 3.46 (1.38, 8.68) 1.17 (0.24, 5.74)

Non-Hispanic other race

(ref = non-Hispanic White)

0.89 (0.44, 1.82) 0.97 (0.39, 2.45) 0.87 (0.38, 2.02) 1.73 (0.55, 5.44) — 1.99 (0.30, 13.02)

Free or reduced-price lunch

(ref = no)

2.36 (1.39, 4.01) 0.39 (0.27, 0.58) 1.09 (0.62, 1.93) 1.15 (0.75, 1.76) 0.55 (0.22, 1.33) 2.88 (0.69, 11.99)

Exposed to tobacco advertising

via the Internet (ref = not

exposed)

0.97 (0.68, 1.37) 1.28 (1.00, 1.65) 0.57 (0.36, 0.90) 0.89 (0.60, 1.30) 2.63 (0.85, 8.11) 0.72 (0.21, 2.52)

Perceived risk: Agreed that “all

tobacco products are

dangerous” (ref = no)

1.64 (1.13, 2.38) 0.82 (0.60, 1.11) 0.62 (0.39, 0.99) 0.91 (0.48, 1.72) 1.15 (0.53, 2.48) 0.47 (0.12, 1.93)

Exposed to secondhand smoke

exposure (ref = not exposed)

1.01 (0.71, 1.43) 0.54 (0.40, 0.75) 1.23 (0.70, 2.18) 2.71 (1.60, 4.59) 2.35 (0.87, 6.34) 0.17 (0.05, 0.62)

Living with a tobacco product

user (ref = no)

1.94 (1.38, 2.71) 0.54 (0.41, 0.71) 1.22 (0.82, 1.82) 0.88 (0.51, 1.50) 0.73 (0.34, 1.58) 0.48 (0.19, 1.24)

Note: Boldface indicates p<0.05.

https://doi.org/10.1371/journal.pone.0217244.t002

Adolescents’ first tobacco products

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Research Question 2—Multivariable multinomial logistic regression

results: First product tried and current tobacco use

Controlling for demographics and relative to initiating tobacco product use via cigarettes, ado-

lescents who initiated tobacco product use via cigars had higher odds of being a single current

tobacco product user (aOR: 2.58, 95% CI: 1.57, 4.25) and higher odds of being a multiple cur-

rent tobacco product user (aOR: 2.33, 95% CI: 1.31, 4.13) (Table 4). In addition, relative to

Table 3. Patterns of Current tobacco product use stratified by first product tried, among ever tobacco users, n = 1020, North Carolina Youth Tobacco Survey a,b,c

,

2017.

Total First tried

cigarettes

First tried e-

cigarettes

First tried

cigars

First tried

SLT

First tried

waterpipe

First tried OTPs (pipe

tobacco, other)

N (%) N (%) N (%) N (%) N (%) N (%) N (%)

No current tobacco product user, n = 380 380

(35.4)

145 (38.7) 145 (39.0) 47 (24.2) 22 (20.8) 16 (63.3) 5 (19.6)

Single current tobacco product user, n = 317

Currently using cigarettes only 40 (4.0) 29 (9.0) 6 (1.4) 1 (0.3) 2 (1.7) 1 (1.8) 1 (7.2)

Currently using cigars only 62 (7.7) 11 (2.5) 6 (3.4) 41 (35.4) 0 (0) 6 (9.9) 4 (20.5)

Currently using e-cigarettes only 182

(19.0)

33 (15.2) 120 (33.5) 10 (5.2) 12 (10.7) 0 (0) 1 (8.0)

Currently using SLT only 19 (2.5) 4 (1.2) 2 (0.5) 0 (0) 12 (16.5) 1 (3.0) 0 (0)

Currently using waterpipe only 9 (0.8) 3 (0.6) 2 (0.4) 1 (0.7) 0 (0) 2 (7.1) 1 (6.4)

Currently using OTPs only 0 (0) 0 (0) 0 (0) 0 (0) 0 (0) 0 (0) 0 (0)

Multiple current tobacco product user (using

2 products, n = 142)

142

(14.6)

52 (14.2) 44 (15.1) 24 (16.0) 18 (15.5) 3 (7.5) 1 (14.3)

Multiple current tobacco product user (using

3 or more products, n = 186)

186

(15.9)

77 (18.6) 24 (6.7) 34 (18.3) 44 (34.7) 4 (7.3) 3 (24.0)

Total 1020

(100)

354 (100) 349 (100) 158 (100) 110 (100) 33 (100) 16 (100)

a Cells with less than 50 participants should be interpreted with caution.

b Percentages provided are column percentages, i.e., the percentage in the cell included in the first column and first row indicates that 35.4% of adolescents who reported

first trying cigarettes currently do not use any tobacco products. c

Categories are mutually exclusive and all percentages add up to 100

https://doi.org/10.1371/journal.pone.0217244.t003

Table 4. Adjusted multinomial logistic regression results—First product tried and current tobacco product use,

among ever tobacco users, n = 1020, North Carolina Youth Tobacco Survey, 2017.

Single current tobacco product use

vs. no current use

Multiple current tobacco product use

vs. no current use

First tried cigars (ref. first tried

cigarettes)

2.58 (1.57, 4.25) 2.33 (1.31, 4.13)

First tried SLT (ref. first tried

cigarettes)

1.66 (0.51, 5.42) 2.45 (1.18, 5.04)

First tried e-cigarettes (ref. first

tried cigarettes)

1.25 (0.80, 1.95) 0.57 (0.34, 0.93)

First tried waterpipe (ref. first

tried cigarettes)

0.46 (0.11, 1.99) 0.29 (0.08, 1.02)

First tried OTP (ref. first tried

cigarettes)

3.56 (0.96, 13.17) 2.99 (0.70, 12.71)

Note: Boldface indicates p<0.05.

Analyses adjust for all demographic correlates.

https://doi.org/10.1371/journal.pone.0217244.t004

Adolescents’ first tobacco products

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initiating tobacco product use via cigarettes, adolescents who initiated tobacco product use via

SLT (aOR: 2.45, 95% CI: 1.18, 5.04) had higher odds of being a multiple current tobacco prod-

uct user, whereas adolescents who initiated tobacco product use via e-cigarettes (aOR: 0.57,

95% CI: 0.34, 0.93) had lower odds of being a multiple current tobacco product user.

Research Question 3—Bivariate results: First product tried and frequency

of tobacco product use

To answer our final research question, we descriptively examined adolescents’ first product

tried and frequency of tobacco product use among current tobacco product users (Table 5).

Among current tobacco product users, 26.6% (n = 187) currently used at least one product fre-

quently and 73.4% (n = 453) did not currently use any products frequently. The prevalence of

frequent tobacco use ranged from a low of 13.9% to a high of 52.0%. In other words, 13.9% of

participants who initiated tobacco product use via e-cigarettes currently used at least one

tobacco product frequently, while 52.0% of participants who initiated tobacco product use via

SLT currently used at least one tobacco product frequently. The prevalence of frequent tobacco

product use was higher among multiple current tobacco product users than single current

tobacco product users; specifically, among single tobacco product users, 12.7% used one prod-

uct frequently, whereas among multiple tobacco product users, 42.1% used at least one product

frequently (p<0.001) (See S3 Table for these results).

Research Question 3—Multivariable logistic regression results: First

product tried and frequency of tobacco product use

Controlling for demographics and relative to initiating tobacco product use via cigarettes

(Table 6), we found that adolescents who initiated tobacco product use via SLT had higher

odds of currently using at least one tobacco product frequently (aOR: 1.90, 95% CI: 1.04, 3.48)

while adolescents who initiated tobacco product use via e-cigarettes had lower odds of cur-

rently using at least one tobacco product frequently (aOR: 0.40, 95% CI: 0.23, 0.70).

Discussion

In this study, we found that many adolescents reported initiating tobacco use with emerging

tobacco products, such as e-cigarettes, alongside other more traditional tobacco products,

Table 5. Bivariate results—First product tried and frequency of tobacco product use, among ever tobacco users, n = 1020, North Carolina Youth Tobacco Survey,

2017 a,b

.

Non-frequent tobacco product use Frequent tobacco product use Total P-value c

N (%) N (%) N (%)

First tried cigarettes 140 (67.9) 69 (32.1) 209 (100) p<0.001

First tried e-cigarettes 169 (86.1) 35 (13.9) 204 (100)

First tried cigars 84 (78.3) 27 (21.7) 111 (100)

First tried SLT 37 (48.0) 51 (52.0) 88 (100)

First tried waterpipe 14 (84.3) 3 (15.7) 17 (100)

First tried OTPs 9 (72.9) 2 (27.1) 11 (100)

a Cells with less than 50 participants should be interpreted with caution.

b Percentages provided are column percentages, i.e., the percentage in the cell included in the first column and first row indicates that 67.9% of adolescents who reported

first trying cigarettes currently do not use any tobacco products frequently.

c P-value is from an omnibus chi-square test.

https://doi.org/10.1371/journal.pone.0217244.t005

Adolescents’ first tobacco products

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such as cigarettes. We also found that trying certain products first, including cigars and SLT,

was associated with higher odds of current multiple tobacco product use, that trying SLT was

associated with higher odds of current frequent tobacco product use, and that trying e-ciga-

rettes first was associated with lower odds of current multiple tobacco product use. Finally, we

found several demographic and psychosocial characteristics, including race/ethnicity and ado-

lescent SES to be associated with first product tried. These results have important implications

for public health.

That as many adolescents reported initiating tobacco use with e-cigarettes as cigarettes is

novel, and suggests that the tobacco product landscape has markedly shifted, particularly

among adolescents. Tobacco prevention efforts need to incorporate increased messaging

about multiple emerging tobacco products, including e-cigarettes. While the US Food and

Drug Administration (FDA) has begun new communication campaigns about e-cigarettes

[25], other efforts to disseminate information about e-cigarettes are needed, especially with the

rise of new, popular brands, such as JUUL which contain large amounts of nicotine and have

increased exponentially among youth [26, 27].

Interestingly, despite the high number of adolescents who reported trying e-cigarettes first,

we found that adolescents who initiated tobacco use via e-cigarettes (relative to cigarettes) had

lower odds of current multiple tobacco product use and lower odds of frequently using at least

one tobacco product. This finding aligns with previous research showing that adolescents who

exclusively use e-cigarettes come from low-risk backgrounds (e.g., they are less likely to have

used alcohol, marijuana, or other drugs, they have a lower propensity for sensation seeking)

[28]. It is therefore, not surprising, that youth who first tried e-cigarettes had lower odds of

being a current multiple tobacco product user or of frequently using tobacco products. How-

ever, this does not mean that youth who try e-cigarettes are at low risk for smoking onset in

prospective analyses. Indeed, other studies have found that youth who try e-cigarettes are at

future risk for using other combustible tobacco products, compared to those who have not

tried e-cigarettes [14–18]. Moreover, it should be noted that in our study, one out of every five

adolescents in our study who first tried e-cigarettes reported using two or more products in

the past 30 days, which suggests that e-cigarettes are not without risks of multiple tobacco

product use. Our findings suggest that educational messages could be tailored to lower-risk

adolescents, in addition to higher-risk groups (such as adolescents from low SES backgrounds)

to avert an increase in adolescent smoking. In addition, longitudinal study designs and nation-

ally representative samples are needed to better understand how youth transition from

Table 6. Adjusted logistic regression results—First product tried and frequency of tobacco product use, among

current tobacco users, n = 640, North Carolina Youth Tobacco Survey, 2017.

Frequent current tobacco product use vs. non-frequent current

tobacco product use

First tried cigars (ref. first tried

cigarettes)

0.66 (0.29, 1.59)

First tried SLT (ref. first tried cigarettes) 1.90 (1.04, 3.48)

First tried e-cigarettes (ref. first tried

cigarettes)

0.40 (0.23, 0.70)

First tried waterpipe (ref. first tried

cigarettes)

0.44 (0.10, 2.02)

First tried OTP (ref. first tried cigarettes) 0.99 (0.18, 5.44)

Note: Boldface indicates p<0.05.

Analyses adjust for all demographic correlates.

https://doi.org/10.1371/journal.pone.0217244.t006

Adolescents’ first tobacco products

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experimenting with tobacco products to using multiple tobacco products over time and differ-

entiate risk factors for why some adolescent e-cigarette users transition to using multiple

tobacco products and others do not.

We also found that adolescents who initiated tobacco use via cigars and SLT (relative to cig-

arettes) had higher odds of current multiple tobacco product use and that adolescents who ini-

tiated tobacco use via SLT had higher odds of currently using at least one tobacco product

frequently. Both findings are novel. While fewer adolescents initiated tobacco use via cigars or

SLT compared to cigarettes or e-cigarettes, more than a quarter of adolescents in this sample

(26.3%) tried these products first, which translates into more than 122,000 high school stu-

dents in NC alone. Moreover, 34.3% and 50.2% of adolescents who had first tried cigars and

SLT, respectively, had transitioned to multiple tobacco product use and 52.0% of adolescents

who had first tried SLT transitioned to using at least one tobacco product frequently (i.e.,

using a product for at least 20 days in the past month). In a previous study of adolescents in

young adults, first use of a non-combustible tobacco product (i.e., SLT and e-cigarettes) was

associated with higher risk of multiple tobacco product use than a combustible tobacco prod-

uct (i.e., cigarettes, cigars, waterpipe) [8]. However, results were not differentiated by product

so it is impossible to determine whether SLT or e-cigarettes were responsible for increased risk

for multiple tobacco product use [8]. It is possible that youth who try cigars and SLT first are

more likely to experiment with other tobacco products and supplement their tobacco use com-

pared to youth who try cigarettes first. Future research should explore why youth who had ini-

tiated tobacco use via cigars and SLT were at greater risk for current multiple tobacco use and

why youth who initiated tobacco use via SLT were at greater risk for currently using at least

one tobacco product frequently.

Previous research has documented disparities in tobacco use by race and SES, with African

American adolescents being more likely to use cigars [29] and lower SES adolescents being

more likely to use cigarettes [30]. Our results extend findings by showing that African Ameri-

can adolescents frequently try cigars and that adolescents of lower SES frequently try cigarettes

as their first products. Consequently, interventions and policies to reduce lower SES adoles-

cents’ and African American adolescents’ access to and availability of cigarettes and cigars,

respectively, are needed to lessen existing tobacco use disparities. For instance, FDA’s current

Fresh Empire campaign focuses on at-risk multicultural youth ages 12–17 who identify with hip-hop culture, specifically African American, Hispanic, and Asian American/ Pacific

Islander youth [31]. While campaign messages currently focus on cigarettes or highlight risks

of any tobacco use [31], opportunities exist for broadening message scope to specifically dis-

cuss other tobacco products, such as cigars or waterpipe which African American and His-

panic youth had odds of trying first in this study.

We also found a number of psychosocial correlates to be associated with first product tried.

For instance, adolescents who were exposed to secondhand smoke and lived with a tobacco

product user had lower odds of initiating tobacco use via e-cigarettes. These findings align

with previous research suggesting that youth who use e-cigarettes come from lower-risk back-

grounds [28]. In addition, adolescents exposed to secondhand smoke had higher odds of initi-

ating tobacco use via SLT; adolescents who lived with a tobacco product user had higher odds

of initiating tobacco use via cigarettes; and adolescents who were exposed to tobacco advertis-

ing via the Internet had higher odds of initiating tobacco use via e-cigarettes. These findings

suggest mechanisms through which tobacco interventions can prevent and reduce tobacco

use. For instance, interventions designed to reduce youth SLT use could focus on reducing

exposure to other tobacco product users by targeting regulations surrounding tobacco use in

public places or interventions designed to reduce youth cigarette use could provide smoking

cessation resources for family members. Moreover, interventions designed to reduce any

Adolescents’ first tobacco products

PLOS ONE | https://doi.org/10.1371/journal.pone.0217244 May 23, 2019 12 / 16

tobacco use could target all of these mechanisms (e.g., exposure to tobacco advertising, per-

ceived risk, exposure to secondhand smoke, and living with tobacco product users) using mul-

tilevel intervention designs.

Limitations

We acknowledge several limitations. First, the survey did not assess age at which high school

students first used tobacco products to verify which product adolescents tried first or reasons

for first trying products. It is possible, for instance, that students first tried a product within

the past 30 days or that they first tried a product several years ago. However, research from

2014–2016 suggests that most youth have tried tobacco products between the ages of 12–14

[32]. Given the age range of high school students in our study (typically between 13–18), it is

likely that for many students, their first product tried was not in the past 30 days. Future

research using additional measures to assess first product tried should be conducted. Second,

all data are self-reported, which may have produced biased results. Third, all data are cross-sec-

tional and we could not examine prospectively how first product tried was associated with

tobacco product use. Fourth, while the use of free or reduced-price lunch has been used previ-

ously as a marker of adolescent SES [22], many schools and districts are moving towards pro-

viding all students free lunch for their students regardless of income. Fifth, all results are from

high school students in North Carolina and findings may not generalize to other states or pop-

ulations. Finally, it is possible that students included in the final sample with complete data dif-

fered from those not included in the final sample. Indeed, in an attrition analysis (see S1

Table), we found that a higher proportion of males, non-white adolescents, and non-current

tobacco product users were not included in the final sample, either due to missing data or

inconsistent data across the different study questions.

Conclusions

In this study, most adolescents reported initiating tobacco use via cigarettes or e-cigarettes and

trying certain products first (e.g., smokeless tobacco) was associated with higher odds of multi-

ple current tobacco product use and higher odds of currently using at least one tobacco prod-

uct frequently. Examining how youth initiate and experiment with tobacco product use

suggest that new efforts focused on emerging tobacco products, such as e-cigarettes, are

needed, but that they should not replace existing efforts focused on preventing and reducing

use of traditional tobacco products, such as cigarettes, cigars, waterpipe, and smokeless

tobacco.

Supporting information

S1 Table. Attrition analysis.

(DOCX)

S2 Table. Bivariate results—Demographic and psychosocial correlates and first product

tried.

(DOCX)

S3 Table. Bivariate results—Frequency of tobacco product use and current tobacco prod-

uct use.

(DOCX)

S1 Data. Data (CSV File).

(CSV)

Adolescents’ first tobacco products

PLOS ONE | https://doi.org/10.1371/journal.pone.0217244 May 23, 2019 13 / 16

Author Contributions

Conceptualization: Sarah D. Kowitt, Adam O. Goldstein, Clare Meernik, Leah M. Ranney.

Data curation: Sarah D. Kowitt, Courtney Heck.

Formal analysis: Sarah D. Kowitt.

Funding acquisition: Adam O. Goldstein, Erin L. Sutfin.

Investigation: Sarah D. Kowitt.

Methodology: Sarah D. Kowitt.

Project administration: Sarah D. Kowitt.

Supervision: Adam O. Goldstein, Erin L. Sutfin, Leah M. Ranney.

Validation: Clare Meernik.

Visualization: Sarah D. Kowitt.

Writing – original draft: Sarah D. Kowitt.

Writing – review & editing: Sarah D. Kowitt, Adam O. Goldstein, Erin L. Sutfin, Amira

Osman, Clare Meernik, Courtney Heck, Leah M. Ranney.

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