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Article
Smoke-Free Ordinances and Policies Protect Youth,
but Ordinances Appear to Have Little Impact on
Non-Combustible Tobacco Use
Nell Valentine 1, Emily McClelland 1and Robert McMillen 1, 2, *
1Mississippi State University, Mississippi State, MS 39759, USA; nell.valentine@ssrc.msstate.edu (N.V.);
emily.mcclelland@ssrc.msstate.edu (E.M.)
2
American Academy of Pediatrics Julius B. Richmond Center of Excellence, Elk Grove Village, IL 60143, USA
*Correspondence: robert.mcmillen@ssrc.msstate.edu; Tel.: +01-662-325-2742
Received: 18 January 2019; Accepted: 7 March 2019; Published: 11 March 2019
Abstract:
Smoke-free ordinances and policies protect youth from exposure to secondhand smoke
(SHS) and cigarette use. This study investigated whether smoke-free ordinances also protect youth
from the use of other tobacco products. We compared the prevalence of SHS exposure, cigarette
smoking, cigar smoking, smokeless tobacco use, and e-cigarette use among high school students
living in a municipality with or without a smoke-free ordinance and in homes with and without
smoke-free policies. Data were analyzed using the 2017 Mississippi Youth Tobacco Survey (n= 1923).
Smoke-free ordinances were found to be associated with lower prevalence of SHS exposure (41.9%
vs. 51.5%), cigarette smoking (5.1% vs. 11.4%), and cigar smoking (7.2% vs. 10.9%). There were no
differences in smokeless tobacco use (6.6% vs. 6.5%) or e-cigarette use (11.2% vs 12.1%). Smoke-free
homes were associated with lower prevalence of SHS exposure (38.0% vs 74.6%), cigarette smoking
(4.8% vs. 17.6%), cigar smoking (6.4% vs. 16.4%), smokeless tobacco use (4.9% vs. 13.2%), and
e-cigarette use (9.6% vs. 19.5%), p< 0.05 for all comparisons. The results suggest that smoke-free
ordinances and policies protect against exposure to tobacco smoke and use of combustible tobacco
products, but smoke-free ordinances do not protect from smokeless tobacco and e-cigarette use.
Tobacco-free, rather than smoke-free, ordinances might offer more protection.
Keywords: smoke-free; tobacco; youth; prevalence; combustible tobacco products; e-cigarette
1. Introduction
Tobacco is the leading cause of preventable death in the United States [
1
]. Although most of the
mortality attributable to tobacco occurs among adults, children’s passive tobacco smoke exposure
harms their health during childhood and adulthood. These harms include higher rates of sudden
infant death syndrome, asthma prevalence and severity, lower respiratory infections, otitis media, and
lung cancer as adults, as well as deleterious effects on behavior and cognition [2–5].
In recognition of these harms, 25 states, and the District of Columbia, have implemented statewide
smoke-free legislation for indoor public places, including restaurants, bars, and workplaces [
6
]. In
private domains, more than eight in ten U.S. households do not allow anyone to smoke inside the
home [
7
]. These restrictions were initially enacted to protect nonsmokers from the harms of secondhand
smoke (SHS) exposure. Subsequent research illustrated another impact, these restrictions were also
found to be associated with decreased prevalence of cigarette smoking, established smoking, and
lower daily cigarette consumption [8–24].
Restrictions on smoking appear to reduce smoking via two routes. First, smoke-free policies
interrupt and inconvenience smoking behaviors. Following the implementation of smoke-free policies,
Children 2019,6, 44; doi:10.3390/children6030044 www.mdpi.com/journal/children
Children 2019,6, 44 2 of 8
smokers may quit or reduce consumption due to the inconvenience of leaving a venue in order to
go to a place where smoking is permitted [
16
,
19
]. Second, smoke-free policies influence the social
climate impacting decisions about smoking. Restrictions that limit cigarette smoking and emphasize
the rights of nonsmokers may also change societal and community norms to be more unfavorable
towards smoking behaviors [25–28].
Smoke-free local ordinances [
10
] and household policies [
29
–
31
] protect youth from exposure
to tobacco smoke and cigarette use. This study investigated whether they were also protected from
the use of other tobacco products. We compared the prevalence of cigarette smoking, cigar smoking,
smokeless tobacco (SLT) use, and e-cigarette use among Mississippi high school students living in
a municipality with or without a smoke-free ordinance; and in homes with and without smoke-free
policies. Overall, the use of these tobacco/nicotine products in Mississippi youth were found to be
similar. There was a statistical difference in past 30-day prevalence of cigarette smoking (7.2%), cigar
smoking (8.4%), smokeless tobacco (6.6%), and e-cigarette use (11.5%) [
32
]. This study investigated
how smoke-free ordinances and policies impact the use of each of these products.
2. Materials and Methods
2.1. Design
Data from the 2017 Mississippi Youth Tobacco Survey (YTS) were used in this study. The Center
for Disease Control’s Office on Smoking and Health developed the methodology and the core content
of the Mississippi Youth Tobacco Survey. The authors developed the supplemental survey items.
The Mississippi YTS was administered to public high school students in the fall of 2017 (n= 1923).
All regular public schools in Mississippi containing at least one grade between 9th and 12th were
included in the sampling frame obtained from the Mississippi State Department of Education. The
Research Triangle Institute (RTI) applied a dual-stage cluster sample design to produce a representative
sample of students. In the first stage, public high schools were selected with a probability proportional
to the enrollment size. In the second stage, classrooms were chosen based on systematic equal
probability sampling within each school and all students in selected classes were eligible to participate.
Each participating school received student surveys, an administration guide, pencils, and parental
waiver of consent forms. Teachers administered the anonymous surveys to students during class time.
The Institutional Review Board for the Protection of Human Subjects in Research (IRB) at Mississippi
State University approved the current study; Approval number 16-176.
2.2. Sample Processing and Weights
•
All completed surveys were sent to RTI for processing and weighting of data. A weighting factor
was applied to each student record to adjust for non-response at the school, class, and student
level. Weight = W1×W2×f1×f2×f3×f4
•W1= inverse of the probability of selecting the school
•W2= inverse of the probability of selecting the classroom within the school
•
f
1
= a school-level non-response adjustment factor calculated by school size (small, medium, large)
•f2= a class adjustment factor calculated by school
•f3= a student-level non-response adjustment factor calculated by class
•f4= a post stratification adjustment factor calculated by gender and grade
2.3. Measures
2.3.1. Smoke-Free Ordinances and Household Rules
Although Mississippi has not enacted a statewide smoke-free ordinance, 151 municipalities had
implemented local smoke-free ordinances at the time of data collection. Mississippi Tobacco Data
provides a summary of Mississippi municipalities with smoke-free ordinances [
33
]. Students who
Children 2019,6, 44 3 of 8
attended high school in a municipality with a smoke-free ordinance were compared to those whose
high school was not in a municipality with a smoke-free ordinance in the fall of 2017.
Students were asked, “Inside your home (not including decks, garages, or porches) is smoking
always allowed, allowed only at certain times or in some places, or never allowed”? Those who
reported “never allowed” were considered to live in a smoke-free home.
2.3.2. Demographic Characteristics and Covariates
Students self-reported gender, age, grade in school, and race. Three categories for race were
applied: white, African-American, and other. Students also responded to “Does anyone who lives
with you now smoke cigarettes?” Those who reported yes were categorized as living with a smoker.
We included this variable as a covariate, given that prior research illustrated that living with a smoker
was a strong predictor of youth smoking initiation and past 30-day use [34].
2.3.3. Secondhand Smoke Exposure and Tobacco Use
Students were asked, “In the past 7 days, did someone smoke tobacco products in your home
while you were there?”, “did you ride in a vehicle where someone was smoking?”, “did you breathe
the smoke from someone who was smoking tobacco in an indoor public place?”, “did you breathe in
the smoke from someone who was smoking tobacco in the place where you work?”, and “did you
breathe the smoke from someone who was smoking tobacco at your school?” Students who reported
yes to any of these questions were considered to have past 7-day exposure to tobacco smoke.
Students were asked, “During the past 30 days, on how many days did you smoke cigarettes?”,
“did you smoke cigars, cigarillos, or little cigars?”, “did you use chewing tobacco, snuff, or dip”, and
“did you use e-cigarettes?” Students who did not report 0 days, were considered to be a past 30-day
user of that product.
2.4. Statistical Analyses
Statistical analyses were conducted using SPSS 22.0 with complex sampling procedures.
Chi-square analyses compared past 7-day exposure to SHS and past 30-day tobacco use among
students who lived in municipalities with a smoke-free ordinance and those that did not as well as
those who lived in homes with and without smoke-free policies. Logistic regression models examined
the relationship of SHS exposure and tobacco use with both smoke-free polices in multivariable
analyses, adjusting for living with a smoker, gender, race, and grade.
3. Results
3.1. Response Rate
Among the schools sampled, 42 out of 50 schools participated (84.0%). Among students in the
classes sampled, 1923 of 2174 students completed usable surveys (88.5%). The final response rate
was 74.3%.
3.2. Sample Characteristics
Unweighted and weighted sample characteristics are presented in Table 1. The sample comprised
of an almost equal number of males and females. Sample weights adjusted for under-representation of
11th graders and African-Americans. Approximately two-thirds of students attended a high school in
a municipality with a smoke-free ordinance, 80%of students lived in a home where smoking was not
allowed, and slightly less than half reported past 7-day exposure to secondhand smoke. Fewer than
one in 10 students reported past 30-day use of cigarettes, cigars, or smokeless tobacco; whereas more
than 10% reported past 30-day e-cigarette use.
Children 2019,6, 44 4 of 8
Table 1. Sample characteristics.
Characteristic Unweighted Sample
Size Unweighted Percent Weighted Percent
Gender: Male 967 50.90% 49.80%
Female 934 49.10% 50.20%
Age: 13 11 0.60% 0.50%
14 481 25.00% 19.40%
15 510 26.50% 26.90%
16 323 16.80% 22.80%
17 455 23.70% 24.10%
18 116 6.00% 5.60%
19+ 10 0.50% 0.40%
Grade: 9th 685 35.90% 27.20%
10th 436 22.80% 25.80%
11th 298 15.60% 24.00%
12th 491 25.70% 23.00%
Race: White 976 51.60% 41.80%
AA 715 37.80% 48.70%
Other 200 10.60% 9.50%
Past 7-day SHS exposure:
Yes 880 47.30% 45.20%
No 982 52.70% 54.80%
Past 30-day cigarette use:
Yes 146 8.10% 7.20%
No 1664 91.90% 92.80%
Past 30-day cigar use:
Yes 163 8.70% 8.40%
No 1704 91.30% 91.60%
Past 30-day SLT use: Yes 139 7.50% 6.60%
No 1721 92.50% 93.40%
Past 30-day e-cigarette
use: Yes 237 12.70% 11.50%
No 1629 87.30% 88.50%
Smoke-free ordinance:
Yes 1256 65.30% 66.40%
No 667 34.70% 33.60%
Home is smoke-free: Yes 1473 80.00% 80.70%
No 368 20.00% 19.30%
Smoker in the home: Yes 583 30.30% 29.20%
No 1340 69.70% 70.80%
3.3. Relationship of Smoke-Free Ordinances and Policies with Secondhand Smoke Exposure and Tobacco Use
Youth who lived in municipalities with smoke-free ordinances were less likely to report any
past 7-day exposure to second tobacco smoke than those who did not; and were also less likely to
report past 30-day cigarette smoking and cigar smoking (see Table 2). However, no association with
smoke-free ordinances and non-combustible tobacco use was detected. Youth were equally likely to
report past 30-day SLT and e-cigarette use.
Table 2. SHS exposure and tobacco use by smoke-free ordinance status.
Outcome Smoke-Free Ordinance No Ordinance p
Past 7-Day SHS Exposure 41.90% 51.50% 0.04
Past 30-Day Cigarette Use 5.10% 11.40% 0.003
Past 30-Day Cigar Use 7.20% 10.90% 0.04
Past 30-Day SLT Use 6.60% 6.50% ns
Past 30-Day E-Cigarette Use 11.20% 12.10% ns
Children 2019,6, 44 5 of 8
Youth who lived in homes with smoke-free policies were less likely to report any past 7-day
exposure to secondhand tobacco smoke than those who did not; and were also less likely to report
past 30-day use of both combustible and non-combustible tobacco products (see Table 3).
Table 3. SHS exposure and tobacco use by smoke-free home status.
Outcome Home is
Smoke-Free
Home is Not
Smoke-Free p
Past 7-Day SHS Exposure 38.00% 74.60% <0.001
Past 30-Day Cigarette Use 4.80% 17.60% <0.001
Past 30-Day Cigar Use 6.40% 16.40% <0.001
Past 30-Day SLT Use 4.90% 13.20% <0.001
Past 30-Day E-Cigarette Use 9.60% 19.50% <0.001
Although both local smoke-free ordinances and household policies influenced SHS exposure
and at least some forms of tobacco use, household policies appear to have a greater impact than
local ordinances in multivariable analyses (see Table 4). In logistic regression models including local
ordinances and household policies, as well as gender, race, and grade; youth who did not live in
smoke-free homes were more likely to be exposed to SHS and use tobacco products than those who
lived in smoke-free homes. Local smoke-free ordinances were not associated with these outcome
measures in multivariable analyses.
Table 4. Logistic regression of SHS exposure and tobacco use on smoke-free policies 1.
Outcome No Smoke-Free Ordinance Home is Not Smoke-Free
OR (95% CI) OR (95% CI)
Past 7-Day SHS Exposure 1.1 (0.9–1.3) 4.3 (3.1–6.1)
Past 30-Day Cigarette Use 1.2 (0.8–1.7) 3.7 (2.3–6.0)
Past 30-Day Cigar Use 1.4 (0.8–2.4) 2.6 (1.5–4.4)
Past 30-Day SLT Use 0.6 (0.4–1.0) 2.6 (1.6–4.2)
Past 30-Day E-Cigarette Use 0.7 (0.4–1.3) 2.1 (1.5–2.9)
1Adjusted for smoker in the home, gender, race, and grade.
4. Discussion
Local smoke-free ordinances and household policies were associated with lower rates of SHS
exposure and cigarette smoking among youth. These results are consistent with previous research
on youth and smoking policies [
29
–
31
]. To our knowledge, this was one of the first studies to
examine whether or not these restrictions also protected youth against other forms of tobacco use.
Household smoke-free policies were also protective against cigar, SLT, and e-cigarette use. Although,
local smoke-free ordinances were also protective against cigar use, they were not associated with
non-combustible use. Youth who lived in places with a smoke-free ordinance were no less likely to use
SLT or e-cigarettes than those who were not protected by a local ordinance.
The results also suggested that household policies had a stronger influence on SHS exposure
and tobacco use than for smoke-free ordinances. Associations in bivariate analyses were stronger and
more consistent for smoke-free home policies than local ordinances; and in multivariable analyses,
smoke-free home policies remained significant predictors of SHS exposure and tobacco use, whereas
local policies did not.
Our data cannot directly explain why household policies had a stronger association with SHS
exposure and tobacco use. Perhaps youth spent more time in their homes than in restaurants and
workplaces, or perhaps youth were more impacted by household norms than community norms.
Household members have more direct control over rules for their homes than for their
municipality, and thus decisions to prohibit smoking may have a greater impact on household youth
Children 2019,6, 44 6 of 8
than local ordinances. Results clearly demonstrated that both of these smoke-free policies were
protective against SHS exposure and combustible tobacco use. Future research should investigate why
local ordinances have a weaker impact on SHS exposure and combustible tobacco use, and why there
was no relationship with non-combustible tobacco use.
There are potential limitations to this study. The sample was limited to youth in Mississippi
public schools and may not be generalized to other populations. Furthermore, youth self-reported
SHS exposure and tobacco use, and these reports were not biologically verified.
5. Conclusions
The results suggested that smoke-free ordinances and policies offer protection against exposure
to tobacco smoke and the use of combustible tobacco products However, smoke-free ordinances
and policies did not appear to impact on non-combustible tobacco use such as through smokeless
tobacco and e-cigarettes. Tobacco-free, rather than smoke-free ordinances might offer more protection
for youth.
Author Contributions:
All authors participated in the conceptual development, the study design, the writing and
editing of the article. Conceptualization, R.M., N.V., and E.M.; methodology, R.M., N.V., and E.M; formal analysis,
R.M., N.V., E.M.; recruitment, N.V. and E.M; project administration, N.V.; writing—original draft preparation,
R.M. and N.V.; writing—review and editing, R.M., N.V., and E.M.; supervision, N.V.; funding acquisition, R.M.
Funding:
This publication was made possible by the Office of Tobacco control, Mississippi State Department of
Health and the Flight Attendant Medical Research Institute (FAMRI) under Award Number #052302_CoE to the
American Academy Pediatrics (AAP). The information, views, and opinions contained herein are those of the
authors and do not necessarily reflect the views and opinions of these organizations.
Conflicts of Interest: The authors declare no conflict of interest.
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2019 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access
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