Foreword

Smoking kills an estimated 434,000 Americans each year, most of whom began smoking during their
adolescence. The key to reducing this enormous death toll and the health consequences that accompany
tobacco use, according to public health officials, is preventing young people from starting to use tobacco.
Very few people begin to use tobacco as adults; almost all first use has occurred by the time people graduate
from high school. By the age of 18, one in three persons is using tobacco.

The earlier young people begin using tobacco, the more heavily they are likey to use it as adults, and
the longer potential time they have to be users. Both the duration and the amount of tobacco use are
related to eventual chronic health problems.

This publication is adapted from Preventing Tobacco Use Among Young People: A Report of the Surgeon Gener-
al released by the U.S. Department of Health and Human Services in 1994. The excerpts presented here
provide important information for educators about the vulnerable ages of 10 through 18 when most users
start smoking, chewing, or dipping and become addicted to tobacco. It underscores the seriousness of
tobacco use and the relationship of tobacco use to other adolescent problem behaviors.

We appreciate the cooperation of the Office of the Surgeon General in making this report available for
distribution by the Department of Education. Copies of the complete document are available for sale by
the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C., 20402,
S/N 017-001-00491-0.
Chapter 1:
Chapter 2:
Chapter 3:

Chapter 4:
Chapter 5:

References

CONTENTS

Introduction .....-.----2+40- ee ee eee
Health Consequences of Tobacco Use by Young People ......

‘Epidemiology of Tobacco Use Among Young People in the
United States 2... et ee es

Psychosocial Risk Factors for Initiating Tobacco Use ........
Efforts to Prevent Tobacco Use Among Young People .......

Pe ee ee

11

39
89

115
183
Preventing Tobacco Use Among Young People

Chapter 1
Introduction

 

Previous Surgeon General's reports on tobacco use
and health have largely focused on the epidemiologic,
clinical, biologic, and pharmacologic aspects of adult use
of tobacco products. This report on Preventing Tobacco
Lse Among Young People provides a more detailed look at
adolescence, the time of life when most tobacco users
begin, develop, and establish their behavior. Because
regular use soon results in addiction to nicotine, this
behavior may persist through adulthood, significantly
increasing, through the extended years of use, the risk of
long-term, severe health consequences.

Despite three decades of explicit health warnings,
large numbers of young people continue to take up
tobacco; currently, over three million adolescents smoke
cigarettes, and over one million adolescent males cur-
rently use smokeless tobacco. Clearly, effective interven-
tions are needed to prevent more young people from
trying tobacco. To achieve significant long-term reduc-
tions in tobacco use and tobacco-related deaths in the
United States, we must examine the nature and scope of
adolescent tobacco use, consider the social, psychologi-
cal, and marketing factors that influence young people in
their decision to use tobacco products, and evaluate cur-
rent efforts to prevent young people from becoming
users. This report addresses the crucial problems of
adolescent tobacco use.

Development of the Report

This report of the Surgeon General was prepared
by the Office on Smoking and Health, National Center
for Chronic Disease Prevention and Health Promotion,
Centers for Disease Control and Prevention, Public Health
Service, U.S. Department of Health and Human Services,
as part of the department’s responsibility, under Public
Law 91-222 and Public Law 99-252, to report current
information on the health effects of cigarette smoking
and smokeless tobacco use to the United States Congress.
This report is the first to focus on the problem of tobacco
use among young people. Given the continuing onset of
use in adolescence and the growing evidence of health
consequences associated with early use, the report was
seen as both needed and timely.

The current report has been produced through the
efforts of experts in the medical, pharmacologic,
epidemiologic, developmental, economic, behavioral,
legal, and public health aspects of smoking and smoke-
less tobacco use among young people. Initial manu-
scripts for the report were prepared by 28 scientists who

were selected for their expertise in specific content areas.
This material was consolidated into chapters, each of
which underwent peer review. The entire document was
reviewed by a number of experts in the field, as wellas by
institutes and agencies within the U.S. Public Health
Service. The final draft of the report was reviewed by
the Assistant Secretary for Health and by the Secretary,
Department of Health and Human Services.

Several concerns guided the development of this
report. The first, which is addressed in Chapter 2, is
whether tobacco use is associated with health conse-
quences during the period of adolescence (broadly de-
fined as ages 10 through 18, although research cited in
this report varies somewhat in the ages considered ado-
lescent). The long-term health consequences—that is,
those that emerge in adulthood—have been the subject
of extensive review and are widely acknowledged in the
scientific and public literature. The chapter thus focuses
on the serious health consequences, as well as the in-
creased risk factors for subsequent health consequences,
that are evident early in life among young smokers and
smokeless tobacco users. Chapter 3 examines the
epidemiologic patterns of tobacco use among the young.
National data on trends in adolescent use are analyzed to
determine the extent of the current problem, as well as to
note changes in patterns of initiation and use. The factors
that influence adolescents in their decision to use tobacco
are examined in Chapter 4, which considers psychosocial
risk factors, and Chapter 5, which examines the influence
of tobacco advertising and promotion. The final concern,
the focus of Chapter 6, was to assess what has been
done—from the individual level to the legislative level—
to prevent tobacco use among young people.

Major Conclusions

1. Nearly all first use of tobacco occurs before high
school graduation; this finding suggests that if ado-
lescents can be kept tobacco-free, most will never
start using tobacco.

2. Most adolescent smokers are addicted to nicotine
and report that they want to quit but are unable to do
so; they experience relapse rates and withdrawal
symptoms similar to those reported by adults.

3. Tobacco is often the first drug used by those young
people who use alcohol, marijuana, and other drugs.

Introduction 5
4. Adolescents with lower levels of school achieve-
ment, with fewer skills to resist pervasive influences
to use tobacco, with friends who use tobacco, and
with lower self-images are more likely than their
peers to use tobacco.

5. Cigarette advertising appears to increase young
people’s risk of smoking by affecting their

Summary

Surgeon General's Repot

perceptions of the pervasiveness, image, and fur
tion of smoking.

6. Communitywide efforts that include tobacco tax
creases, enforcement of minors’ access laws, yout
oriented mass media campaigns, and school-bas
tobacco-use prevention programs are successful

- reducing adolescent use of tobacco.

 

Introduction

The health effects of cigarette smoking have been
the subject of intensive investigation since the 1950s. Ciga-
rette smoking is still considered the chief preventable
cause of premature disease and death in the United
States. As was documented extensively in previous Sur-
geon General's reports, cigarette smoking has been caus-
ally linked to lung cancer and other fatal malignancies,
atherosclerosis and coronary heart disease, chronic ob-
structive pulmonary disease, and other conditions that
constitute a wide array of serious health consequences
(USDHHS 1989). More recent studies have concluded
that passive (or involuntary) smoking can cause disease,
including lung cancer, in healthy nonsmokers. In 1986,
an advisory committee appointed by the Surgeon Gen-
eral released a special report on the health consequences
of smokeless tobacco, concluding that smokeless tobacco
use can cause cancer and can lead to nicotine addiction
(USDHHS 1986). In the 1988 report, nicotine was desig-
nated a highly addictive substance, comparable in its
physiological and psychological properties to other ad-
dictive substances of abuse (USDHHS 1988).

Considerable evidence indicates that the health
problems associated with smoking are a function of the
duration (years) and the intensity (amount) of use. The
younger one begins to smoke, the more likely one is to be
a current smoker as an adult. Earlier onset of cigarette
smoking and smokeless tobacco use provides more life-
years to use tobacco and thereby increases the potential
duration of use and the risk of a range of more serious
health consequences. Earlier onset is also associated
with heavier use; those who begin to use tobacco as
younger adolescents are among the heaviest users in
adolescence and adulthood. Heavier users are more
likely to experience tobacco-related health problems and
are the least likely to quit smoking cigarettes or using
smokeless tobacco. Preventing tobacco use among young
people is therefore likely to affect both duration and

6 Introduction

intensity of total use of tobacco, potentially reducing
long-term health consequences significantly.

Health Consequences of Tobacco Use
Among Young People

Active smoking by young people is associated
with significant health problems during childhood
and adolescence and with increased risk factors for
health problems in adulthood. Cigarette smoking
during adolescence appears to reduce the rate of lung
growth and the level of maximum lung function that
can be achieved. Young smokers are likely to be less
physically fit than young nonsmokers; fitness levels
are inversely related to the duration and the intensity
of smoking. Adolescent smokers report that they are
significantly more likely than their nonsmoking peers
to experience shortness of breath, coughing spells,
phlegm production, wheezing, and overall dimin-
ished physical health. Cigarette smoking during child-
hood and adolescence poses a clear risk for respiratory
symptoms and problems during adolescence; these
health problems are risk factors for other chronic con:
ditions in adulthood, including chronic obstructive
pulmonary disease.

Cardiovascular disease is the leading cause 0
death among adults in the United States. Atheroscle
rosis, however, may begin in childhood and becom«
clinically significant by young adulthood. Cigarett
smoking has been shown to be a primary risk facto
for coronary heart disease, arteriosclerotic periphera
vascular disease, and stroke. Smoking by childre:
and adolescents is associated with an increased risk o
early atherosclerotic lesions and increased risk factor
for cardiovascular diseases. These risk factors includ
increased levels of low-density lipoprotein cholestero!
increased very-low-density lipoprotein cholestero
increased triglycerides, and reduced levels a
Preventing Tobacco Use Among Young People

high-density lipoprotein cholesterol. If sustained into
adulthood, these patterns significantly increase the risk
for early development of cardiovascular disease.

Smokeless tobacco use is associated with health
consequences that range from halitosis to severe health

roblems such as various forms of oral cancer. Use of
smokeless tobacco by young people is associated with
early indicators of adult health consequences, including
periodontal degeneration, soft tissue lesions, and general
systemic alterations. Previous reports have documented
that smokeless tobacco use is as addictive for young
people as it is for adults. Another concern is that smoke-
less tobacco users are more likely than nonusers to be-
come cigarette smokers.

Among addictive behaviors suchas the use of alco-
hol and other drugs, cigarette smoking is most likely to
become established during adolescence. Young people
who begin to smoke at an earlier age are more likely than
later starters to develop long-term nicotine addiction.
Most young people who smoke regularly are already
addicted to nicotine, and they experience this addiction
in a manner and severity similar to what adult smokers
experience. Most adolescent smokers report that they
would like to quit smoking and that they have made
numerous, usually unsuccessful attempts to quit. Many
adolescents say that they intend to quit in the future and
yet prove unable to doso. Those who try to quit smoking
report withdrawal symptoms similar to those reported
by adults. Adolescents are difficult to recruit for formal
cessation programs, and when enrolled, are difficult to
retain in the programs. Success rates in adolescent cessa-
tion programs tend to be quite low, both in absolute
terms and relative to control conditions.

Tobacco use is associated with a range of problem
behaviors during adolescence. Smokeless tobacco or
cigarettes are generally the first drug used by young
people in a sequence that can include tobacco, alcohol,
marijuana, and hard drugs. This pattern does not imply
that tobacco use causes other drug use, but rather that
other drug use rarely occurs before the use of tobacco.
Still, there are a number of biological, behavioral, and
social mechanisms by which the use of one drug may
facilitate the use of other drugs, and adolescent tobacco
users are substantially more likely to use alcohol and
illegal drugs than are nonusers. Cigarette smokers are
also more likely to get into fights, carry weapons, attempt
suicide, and engage in high-risk sexual behaviors. These
problem behaviors can be considered a syndrome, since
involvement in one behavior increases the risk for in-
volvement in others. Delaying or preventing the use of
tobacco may have implications for delaying or prevent-
ing these other behaviors as well.

The Epidemiology of Tobacco Use Among
Young People .

Overall, about one-third of high-school-aged ado-
lescents in the United States smoke or use smokeless
tobacco. Smoking prevalence among U.S. adolescents
declined sharply in the 1970s, but this decline slowed
significantly in the 1980s, particularly among white males.
Although female adolescents during the 1980s were more
likely than male adolescents to smoke, female and male
adolescents are now equally likely to smoke. Male ado-
lescents are substantially more likely than females to use
smokeless. tobacco products; about 20 percent of high
school males report current use, whereas only about 1
percent of females do. White adolescents are more likely
to smoke and to use smokeless tobacco than are black
and Hispanic adolescents.

Sociodemographic, environmental, behavioral, and
personal factors can encourage the onset of tobacco use
among adolescents. Young people from families with
lower socioeconomic status, including those adolescents
living in single-parent homes, are at increased risk of
initiating smoking. Among environmental factors, peer
influence seems to be particularly potent in the early
stages of tobacco use; the first tries of cigarettes and
smokeless tobacco occur most often with peers, and the
peer group may subsequently provide expectations, re-
inforcement, and cues for experimentation. Parental
tobacco use does not appear to be as compelling a risk
factor as peer use; on the other hand, parents may exert a
positive influence by disapproving of smoking, being
involved in children’s free time, discussing health mat-
ters with children, and encouraging children’s academic
achievement and school involvement.

How adolescents perceive their social environment
may be a stronger influence on behavior than the actual
environment. For example, adolescents consistently over-
estimate the number of young people and adults who
smoke. Those with the highest overestimates are more
likely to become smokers than are those with more accu-
rate perceptions. Similarly, those who perceive that ciga-
rettes are easily accessible and generally available are
more likely to begin smoking than are those who per-
ceive more difficulty in obtaining cigarettes.

Behavioral factors figure heavily during adoles-
cence, a period of multiple transitions to physical matu-
ration, to a coherent sense of self, and to emotional
independence. Adolescents are thus particularly vulner-
able to a range of hazardous behaviors and activities,
including tobacco use, that may seem to assist in these
transitions. Young people who report that smoking serves
positive functions or is potentially useful are at increased
risk for smoking. These functions are associated with

Introduction 7
bonding with peers, being independent and mature, and
having a positive social image. Since reports from
adolescents who begin to smoke indicate that they have
lower self-esteem and lower self-images than their non-
smoking peers, smoking can become a self-enhancement
mechanism. Similarly, not having the confidence to be
able to resist peer offers of tobacco seems to be an impor-
tant risk factor for initiation. Intentions to use tobacco
and actual experimentation also strongly predict subse-
quent regular use.

The positive functions that many young people
attribute to smoking are the same functions advanced in
most cigarette advertising. Young people are a strategi-
cally important market for the tobacco industry. Since
most smokers try their first cigarette before age 18, young
people are the chief source of new consumers for the
tobacco industry, which each year must replace the many
‘consumers who quit smoking and the many who die
from smoking-related diseases. Despite restrictions on
tobacco marketing, children and adolescents continue to
be exposed to cigarette advertising and promotional ac-
tivities, and young people report considerable familiar-
ity with many cigarette advertisements. In the past, this
exposure was accomplished by radio and television pro-
grams sponsored by the cigarette industry. Barred since
1971 from using broadcast media, the tobacco industry
increasingly relies on promotional activities, including
sponsorship of sports events and public entertainment,
outdoor billboards, point-of-purchase displays, and the
distribution of specialty items that appeal to the young.
Cigarette advertisements in the print media persist; these
messages have become increasingly less informational,
replacing words with images to portray the attractive-
ness and function of smoking. Cigarette advertising fre-
quently uses human models or human-like cartoon
characters to display images of youthful activities, inde-
pendence, healthfulness, and adventure-seeking. In pre-
senting attractive images of smokers, cigarette
advertisements appear to stimulate some adolescents
who have relatively low self-images to adopt smoking as
a way to improve their own self-image. Cigarette adver-
tising also appears to affect adolescents’ perceptions of
the pervasiveness of smoking, images of smokers, and
the function of smoking. Since these perceptions are
psychosocial risk factors for the initiation of smoking,
cigarette advertising appears to increase young people’s
risk of smoking.

Efforts to Prevent the Onset of Tobacco Use

Most of the U.S. public strongly favors policies that
might prevent tobacco use among young people. These
policies include mandated tobacco education in schools,
acomplete ban on smoking by anyone on school grounds,

8 Introduction

Surgeon General's Report

further restrictions on tobacco advertising and promo-
tional activities, stronger prohibitions on the sale of to-
bacco products to minors, and increases in earmarked
taxes on tobacco products. Interventions to prevent ini-
tiation among young people—even actions that involve
restrictions on adult smoking or increased taxes—have
received strong support among smoking and nonsmok-
ing adults.

Numerous research studies over the past 15 years
suggest that organized interventions can help prevent
the onset of smoking and smokeless tobacco use. School-
based smoking-prevention programs, based on a model -
of identifying social influences on smoking and provid-
ing skills to resist those influences, have demonstrated
consistent and significant reductions in adolescent smok-
ing prevalence; these program effects have lasted one to -
three years. Programs to prevent smokeless tobacco use ~
have used a similar model to achieve modest reductions
in initiation of use. The effectiveness of these school-—
based programs appears to be enhanced and sustained,
at least until high school graduation, by adding coordi-
nated communitywide programs that involve parents,
youth-oriented mass media and counteradvertising, com-
munity organizations, or other elements of adolescents’
social environments.

A crucial element of prevention is access: adoles-
cents should not be able to purchase tobacco products in
their communities. Active enforcement of age-at-sale —
policies by public officials and community members ap-
pears necessary to prevent minors’ access to tobacco.
Communities that have adopted tighter restrictions have
achieved reductions in purchases by minors. At the state
and national levels, price increases have significantly
reduced cigarette smoking; the young have been at least
as responsive as adults to these price changes. Maintain-
ing higher real prices of cigarettes provides a barrier to
adolescent tobacco use but depends on further tax in-
creases to offset the effects of inflation. The results of this
review thus suggest that a coordinated, multicomponent
campaign involving policy changes, taxation, mass me-
dia, and behavioral education can effectively reduce the
onset of tobacco use among adolescents.

Summary

Smoking and smokeless tobacco use are almost
always initiated and established in adolescence. Besides
its long-term effects on adults, tobacco use produces
specific health problems for adolescents. Since nicotine
addiction also occurs during adolescence, adolescent to-
bacco users are likely to become adult tobacco users.
Smoking and smokeless tobacco use are associated with
other problem behaviors and occur early in the sequence

-of these behaviors. The outcomes of adolescent smoking
Preventing Tobacco Use Among Young People

and smokeless tobacco use continue to be of great public
health importance, since one out of three U.S. adoles-
cents uses tobacco by age 18. The social environment of
adolescents, including the functions, meanings, and im-
ages of smoking that are conveyed through cigarette
advertising, sets the stage for adolescents to begin using
tobacco. As tobacco products are available and as peers
begin to try them, these factors become personalized and

References

relevant, and tobacco use may begin. This process most
affects adolescents who, compared with their peers, have
lower self-esteem and self-images, are less involved with
school and academic achievement, have fewer skills to
resist the offers of peers, and come from homes with
lower socioeconomic status. Tobacco-use prevention
programs that target the larger social environment of
adolescents are both efficacious and warranted.

 

US DEPARTMENT OF HEALTH AND HUMAN SERVICES.
The health consequences of using smokeless tobacco. A report of the
advisory committee to the Surgeon General. US Department of
Health and Human Services, Public Health Services, National
Institutes of Health. NIH Publication No. 86-2874, 1986.

US DEPARTMENT OF HEALTH AND HUMAN SERVICES.
The health consequences of smoking: nicotine addiction. A report of
the Surgeon General, 1988. US Department of Health and
Human Services, Public Health Service, Centers for Disease
Control, Center for Health Promotion and Education, Office
on Smoking and Health. DHHS Publication No. (CDC)
88-8406, 1988.

US DEPARTMENT OF HEALTH.AND HUMAN SERVICES.
Reducing the health consequences of smoking: 25 years of progress.
A report of the Surgeon General. US Department of Health and
Human Services, Public Health Service, Centers for Disease
Control, Center for Chronic Disease Prevention and Health
Promotion, Office on Smoking and Health. DHHS Publication
No. (CDC) 89-8411, 1989.
Preventing Tobacco Use Among Young People

Chapter 2: The Health Consequences of Tobacco Use by Young People

Introduction

 

The health consequences of tobacco use among
adults have been reviewed extensively in previous
Surgeon General’s reports (Public Health Service
[PHS] 1964; U.S. Department of Health and Human
Services [USDHHS] 1986b, 1989). Among young people,
the short-term health consequences of smoking include
respiratory and nonrespiratory effects, addiction to a
toxic substance (nicotine), and the associated risk of other

drug use. Long-term health consequences of adolescent
smoking may be seen in the association between early
onset of tobacco use and future (adult) smoking, with
concomitant health consequences. Passive (also called
“involuntary”) smoking during adolescence is also asso-
ciated with harmful respiratory and nonrespiratory
effects. Lastly, the use of smokeless tobacco poses seri-
ous health consequences to young people.

Health Consequences of Smoking Among Young People

 

Introduction

The health effects of cigarette smoking have been
the subject of intensive investigation since the 1950s.
Extensive evidence, documented in numerous reports of
the Surgeon General, has causally linked cigarette
smoking to a wide array of health outcomes that extend
from annoying symptoms to fatal malignancies
(USDHHS 1989). Until recently, this research was largely
directed at the effects of smoking on adults. As is
discussed in Chapter 3 (see “Age or Grade When Smok-
ing Begins”), the onset and development of cigarette
use occur primarily during adolescence (USDHHS 1989);
the health consequences of smoking among young
people thus have great public health significance. In
recent years, investigations of the health effects in school-
age youth have reported sufficient data to support
conclusions about adverse effects of smoking during
childhood and adolescence.

Most of the evidence reviewed here is gathered
from epidemiologic studies of young people ranging
from 10 through 20 years old. Selected studies that relate
to older age groups, yet are relevant to young people,
are also included. Emphasis is placed on the res-
piratory effects of smoking, for which the evidence is
abundant. Data on smoking and cardiovascular
risk factors and atherogenesis are also addressed, as
are the adult health implications of starting to smoke
during childhood.

Overview of the Toxicology of
Tobacco Smoke

Cigarette smoke is a complex mixture of organic
and inorganic compounds generated by the combustion
of tobacco and additives. Current knowledge about the

physicochemical nature of tobacco smoke is well de-
scribed in earlier Surgeon General’s reports (PHS 1964;
USDHHS 1981, 1989). Thousands of individual com-
pounds have been isolated in cigarette smoke, including
pharmacologically active agents (e.g., nicotine), toxic
agents (e.g., carbon monoxide, hydrogen cyanide, and
acrolein), and mutagens and carcinogens (e.g., polycy-
clic aromatic hydrocarbons).

Cigarette smoke is further classified as mainstream
smoke (MS), the smoke drawn through the mouthpiece
of the cigarette, and sidestream smoke (SS), the smoke
given off by smoldering tobacco between puffs and the
smoke diffusing through the cigarette paper and escap-
ing from the burning cone during puffing. Because of the
differing combustion conditions under which MS and SS
are generated, their chemical compositions differ; in par-
ticular, undiluted SS tends to have higher concentrations
of many toxic and tumorigenic agents (USDHHS 1986a,
1989). The quantitative yields of tar (the material depos-
ited ina filter as MS is being drawn), nicotine, and carbon
monoxide from cigarettes can be assessed by using a
smoking machine standardized to a particular pattern of
puffing (USDHHS 1989).

Passive smoking refers to nonsmokers’ inhalation
of tobacco smoke. The term “environmental tobacco
smoke” (ETS) is now widely used to refer to the mixture
of predominantly SS and exhaled MS that is inhaled by
the passive smoker. Passive smoking was the subject of
the 1986 Surgeon General's report (USDHHS 1986a); that
report reviews in detail the components of ETS, as did a
contemporaneously prepared report of the N ational Re-
search Council (1986). In 1991, the National Institute for
Occupational Safety and Health recommended that ETS
be regarded as a potential occupational carcinogen and

Health Consequences 11
that exposures to ETS be reduced to the lowest feasible
concentration (USDHHS 1991b). A recent monograph
by Guerin, Jenkins,.and Tomkins (1992) updates and
extends these earlier reviews. The U.S. Environmental
Protection Agency (USEPA) also recently reviewed the
evidence on involuntary smoking and respiratory health
(USEPA 1992). These and other health consequences of
passive smoking are discussed later in this chapter.

Many of the components of SS and MS have been
identified in ETS. On the other hand, ETS is an inherently
dynamic mixture that changes in physical and chemical
characteristics as it ages and reacts with other pollutants
in indoor air and with surfaces (USDHHS 1986a; Guerin,
Jenkins, Tomkins 1992). The 1986 Surgeon General’s
report concluded, however, that ETS was sufficiently
close to MS and SS to permit generalization of the evi-
dence on the health consequences of active smoking to
passive smoking (USDHHS 1986a). ,

The human body is most susceptible to these health
consequences along cigarette smoke’s path of ingress
through the respiratory tract. The respiratory tract in-
cludes the upper airway (nose, oropharynx, and larynx)
and the lung (airways and the parenchyma). The air-
ways are lined by an epithelium that varies in form and
function at different levels of the respiratory tract. The
parenchyma includes the alveoli pulmonis (the delicate
gas-exchanging surface of the lung) and the interstitium
(the location of the blood and lymphatic vessels and of
the lung’s supporting connective tissue).

The effects of active’ cigarette smoking on these
structures of the lung and on many physiological func-
tions of the lung have been extensively studied (USDHHS
1984, 1990; Bates 1989). Changes in lung physiology
attributable to smoking include the weakening of an
individual’s defenses against infectious organisms and
inhaled particles and gases, changes in the numbers and
types of cells present within the lung, and the activation
of potentially damaging proteolytic enzymes and the
inactivation of the proteins that inhibit them. Many of
these effects of smoking have been demonstrated in young
adult smokers who have served as volunteer research
subjects (USDHHS 1984).

The effects of smoking on lung structure and func-
tion have been demonstrated repeatedly in young adult
smokers (USDHHS 1984; Bates 1989).. Studies using
spirometry, tests of small airway function, and lung vol-
ume measurements have shown a higher frequency of
abnormalities in smokers than nonsmokers (USDHHS
1984; Bates 1989). Effects of smoking on lung structure,
particularly the small airways, have been found in smok-
ers in their mid-twenties. Niewoehner, Kleinerman, and

 

Unless otherwise indicated, "smoking" will hence refer to
active smoking.

12. Health Consequences

Surgeon General's Report

Rice (1974) examined peripheral airways of 20 nonsmok-
ers and 19 smokers who had died from nonrespiratory
causes at an average age of 25. A characteristic lesion,
termed “respiratory bronchiolitis,” was found in all 19 of
the smokers but in only 5 of the nonsmokers. The
affected small airways of the smokers demonstrated
an inflammatory process consisting of aggregates of
pigment-containing macrophages with edema, fibrosis,
and epithelial hyperplasia in adjacent bronchioles
and alveoli.

These observations on the effects of smoking in
young people are consistent with current concepts of
pathogenesis and natural history in adult smokers
(USDHHS 1984, 1990). Severe chronic airflow obstruc-
tion, sufficient to result in a clinical diagnosis of chronic
obstructive pulmonary disease (COPD), follows sustained
smoking and lung injury with progressive loss of respi.
ratory function through adulthood. In smokers whc
develop COPD, decline of lung function at a rate wel
beyond that associated with aging alone eventually lead:
to impairment. Changes in lung function can be demon
strated in young adult smokers; these losses are consis
tent with the histopathologic evidence that the smal
airways of young smokers are damaged (U! SDHHS 1984)

Epidemiologic Evidence of Respiratory

Effects
Respiratory Symptoms

The cardinal symptoms of respiratory tract injur
and disease are cough, sputum production, wheezing
and dyspnea (or shortness of breath). In epidemiologi
studies of respiratory diseases, symptoms are usualk
discovered through responses to a standardized ques
tionnaire (Samet 1978). In adults, the occurrence of coug!
and phlegm is causally associated with cigarette smok
ing; the frequency of the symptoms rises with the num
ber of cigarettes smoked per day (USDHHS 1984). I
some studies, wheezing is also more frequent in adu
smokers than in adults who have never smoke
(Schenker, Samet, Speizer 1982). The frequency ¢
dyspnea rises as the extent of smoking-related impait
ment of lung function increases (Samet 1978).

Questionnaire-based epidemiologic studies of chi
dren and adolescents document that smoking is also
cause of respiratory symptoms in preteen and teenag
regular smokers (those who smoke at least weekly
Studies conducted from the 1960s through the 198
involving thousands of children provide consistent ev
dence that smoking is associated with the occurrence |
cough and phlegm (Table 1; see Table 31 in Chapter 3 fe
additional data). In several studies, smoking also i
creased the frequency of wheezing and dyspnea. The:
associations have been found in studies conducted in tt
Preventing Tobacco Use Among Young People

United States, the United Kingdom, New Zealand, and
Scandinavia and at levels of smoking as low as one
cigarette per week.

In one of the first studies on smoking and respira-
tory symptoms in children, Holland and Elliott (1968)
administered a questionnaire concerning respiratory
symptoms and cigarette smoking to all children in
schools in four areas of southeast England. Smoking
education was then provided to half of the schools, and
the questionnaire was readministered one year later.
Although the intervention had no effect on the preva-
lence of smoking, the study documented that smoking in
childhood was associated with cough and phlegm and
that these symptoms were reduced in those who had
stopped smoking.

Many later studies continued to show that smok-
ing increased the frequency of respiratory symptoms in
children and adolescents. In the United States, research
with high school students (Addington et al. 1970; Seely,
Zuskin, Bouhuys 1971; Rush 1974) and college students
(Peters and Ferris 1967) provided early evidence of ad-
verse effects of smoking on young smokers. Large stud-
ies of schoolchildren (including preteens) in the United
Kingdom showed that symptom rates were increased by
smoking. Bewley, Halil, and Snaith (1973) reported that
the frequency of cough was increased in boys and girls
no older than 11.5 years who reported smoking at least
one cigarette per week. Other studies in the United
Kingdom and the United States found further evidence
of the effects of smoking on symptom frequency in chil-
dren of similar ages (Bewley and Bland 1976; Charlton
1984; see Table 31 in Chapter 3).

The health effects of smoking among adolescents
may be confounded by a history of passive smoking if
the parents of an adolescent smoker also smoke. How-
ever, in a study of 5,835 secondary schoolchildren in
Derbyshire (United Kingdom), students who smoked at
least one cigarette per week persisted in having an in-
creased risk for cough and dyspnea even after parental
smoking was taken into account (Bland et al. 1978).

Control for other potential confounding or mediat-
ing factors varies among the investigations. Residence
location, a surrogate for exposure to ambient air pollu-
tion, was considered in several of the studies (Bewley,
Halil, Snaith 1973; Bewley and Bland 1976), and a study
of 20-year-olds (Colley, Douglas, Reid 1973) controlled
for socioeconomic status.

Lung Function

Numerous cross-sectional studies of adults have
shown that cigarette smokers have a lower level of lung
function, as assessed by tests of lung mechanics and gas
exchange, than persons who have never smoked

(USDHHS 1984; Bates 1989). Longitudinal studies show
that smoking speeds the age-related decline of lung func-
tion. The most abundant evidence describes changes in
lung function as assessed by spirometry, or the measure
of the volume of air entering and leaving the lungs. One
measure of scientific and clinical interest obtained through
spirometry is the forced expiratory volume in one se-
cond (FEV,), the volume of air blown out during the
first second of the forced vital capacity maneuver.
FEV, increases with lung growth and development dur-
ing childhood, and rises even more steeply with the
growth spurt of adolescence (Tager et al. 1988; Sherrill
et al. 1992). In persons who have never smoked,
FEV, begins to decline from a maximum at some time
during the third or fourth decades of life (Beck, Doyle,
Schachter 1982; Tager et al. 1988). In smokers, the age-
related decline commences at a younger age and pro-
ceeds at a steeper average rate (Beck, Doyle, Schachter
1982; USDHHS 1984; Tager et al. 1988). When people
stop smoking, their average decline gradually returns
to the rate observed in those who never smoked
(USDHHS 1990).

Cross-sectional and longitudinal data show that
smoking also adversely affects lung function in children
and adolescents (Table 2). The evidence comes princi-
pally from spirometry studies of high school students,
although one of the first studies to show reduced lung
function in young people involved college seniors (Pe-
ters and Ferris 1967). In these studies, impaired lung
function has been primarily indicated through reduced
flow rates after 50 percent or more of the vital capacity
has been exhaled. This effort-independent, latter portion
of the flow-volume loop is sensitive to abnormalities of
the lung’s small airways and the lung parenchyma (Bates
1989). Several studies have also found that smokers have
a reduced peak expiratory flow rate (PEFR) (Table 2).
This effort-dependent portion of the flow-volume loop is
more sensitive to abnormal function of the lung’s larger
airways than of its small airways (Bates 1989).

Among the first researchers to study smoking
among younger people were Peters and Ferris (1967), who
obtained spirometric and peak-flow data from 124 Harvard
College seniors. Smokers had lower (although not signifi-
cantly) FEV, than persons who had never smoked. Spiro-
metric flow rates and PEFR were significantly lower in the
smokers. In an early study involving high school students,
Seely, Zuskin, and Bouhuys (1971) found evidence of abnor-
mal function of the small airways in both boys and girls who
smoked. Subsequent cross-sectional studies of teenagers
have tended to confirm that smokers have reduced lung
function, as assessed by spirometry or PEFR measurement.

More recent, longitudinal data show that smoking
reduces the rate of lung growth, as would be anticipated

Health Consequences 13
Surgeon General's Report

Table1. Published studies of the effects of smoking on respiratory symptoms among young people,

various countries, 1965-1983

Reference* Location/year Study population

Massachusetts, 1965 124 Harvard College seniors

Peters and Ferris 1967

   

Addington et al. 1970 Oklahoma’

 

England, 1971

   
  
 

“ndiaba Do dey ie

Bewley, Halil, Snaith 1973

8,682 schoolchildren
aged 10 and 11 years

12,595 high school students aged

Rush 1974 New York, 1968
13-18 years

 

 

*Listed chronologically by publication date.
SYear not provided.

14. Health Consequences
Preventing Tobacco Use Among Young People

 

Prevalence (%) by smoking status

 

 

Symptoms

Never smoker Smoker*
Phlegm 2 3 months/yr 2.4 26.54
Breathlessness 2.4 20.5+
Wheezing (apart from colds) 7.3 31.3#
Colds go to chest 4.9 31.3¢

 

 

 

f ough
Never smoker Smoker’
Daily cough 2 3 months 4 10
Daily phlegm 2 3 months 3 9
Dyspnea when hurrying 16 30
Chest cold for 1 week 22 30
Wheezing or asthma 12 13

   

 

Never smoker Smoker*
Morning cough
Boys 5.4 18.2
Girls 5.9 19.8
Cough 3 months
Boys 3.8 15.4
3.5 12.1

 

 

 

 

 

Nonsmoker Ex-smoker Smoker
Number of cigarettes smoked per day
Cough 2 3 months/yr" $1-9 10-14 215
Boys 2.9 45 9.2 16.2 29.0
Girls 4.4 6.0 12.0 23.1 35.9

‘At least one cigarette daily for the past year.

tp < 0.01.

“Smoking at least one cigarette weekly. Percentages combine data reported separately in authors’ Table 4 for urban
and rural children.

For white children only.

Health Consequences 15
Surgeon General's Repor

Table 1. Continued
Reference Location/year Study population

Maori and European high school

Stanhope and Prior 1975 New Zealand, 1972
, ars

 
 
    
   
  
  

 

 

es ag TES

  

Spy egy tee eet oe oH

Bewley and Bland 1976 a England, 19

  

 

 
  

 

“he Le

fon de ee UL oe ilo

 

England, 1974 5,835 schoolchildren; first-year

Bland et al. 1978
level in secondary school

 

wr phe re

tts, 1975,

     
  
   
         

Massachuse

    

 

2 TOAD ates

Kujala 1981 Finland, 1976

 

Charlton 1984

 

Adams et al. 1984

Rimpela and Rimpela 1985.

 

iad Ibo ely Sek ime 1 Pe

Oechsili, Seltzer, California, 1977-1979 1,445 children in a cohort
van den Berg 1987 study

“Smoking at least one cigarette weekly. Percentages combine data reported separately in authors’ Table V for urban and rural children.
RR = Relative risk for children smoking > one cigarette weekly versus children who had never smoked, adjusted for parental smoking.

#Smoking at least one cigarette weekly.

16 Health Consequences
preventing Tobacco Use Among Young People

 

Symptoms Prevalence (%) by smoking status

 

General finding: Cough grade, phlegm grade, and loose cough sign significantly associated with smoking.

       
  
 

 
  

 

ee
¢

 

 

 

 

ote. Never smoke

Morning cough : vg tee

Boys ~~:

Girls © fs
Cough 3 months

Boys ao

Girls.

Never smoker Smoker RRS

Morning cough

Boys 3.1 19.2 5.9

Girls 1.8 13.5 6.8
Cough day or night

Boys 20.4 46.5 2.4

Girls 18.5 47.3 2.6
Breathlessness

Boys 11.8 34.9 2.9

Girls 16.5 39.2 2.3

 

 
 

    

 

 

 

 

difference not significant.

Nonsmoker“ Ex-smokert! Smoker***
Cough ail day 1 2 8
Phlegm all day 1 1 7
Wheezing 5 13 22

 

 

  
  
    

 

 

 

 

 

Morning phlegm
Morning cough

Phlegm day or night
Cough day or night

age,

 

   

 

General findings: Starting smoking associated with bronchitis and pneumonia.

 

*RR = Relative risk for children smoking at least one cigarette weekly versus children who had never smoked.
“Nonsmoker = Never smoking and smoking not more than one cigarette daily for < one year.
NEx-smoker = Smoking one month or more before date of the interview.
“Smoker = Smoking > 1g of tobacco daily; one cigarette was estimated to contain 1g of tobacco.
Smoking daily, cigarettes < 10mg of tar.
"Smoking daily, cigarettes 10-18mg of tar.
Health Consequences 17
Surgeon General's Repor

 

 

Table2. Published studies of the effects of smoking on lung function among young people, various
countries, 1965-1981 ,
; Study
Reference* Location/year population Findings' Comment
Peters and Ferris | Massachusetts, 124 Harvard ’ Significant reduction Age distribution
1967 1965 College seniors in spirometric flow not given, non-

klahomat?

  

Addington et al.
1970 ~..:

  

   

spt

195 male and 170

 

Seely, Zuskin,

Connecticut?
Bouhuys 1971 female high
school students
aged 15-19 years

vik SSNs: if Pte tick
Comstock and Nationwide, 3,409 U.S. Navy
Rust 1973 1970-1971 recruits, median
age = 19 years

PEFR lower in

rates when compar-
ing NS with persons
smoking a pack a day
for four years during
college; dose response
with amount smoked.

   
   
    
   
    
  

From MEFV curves,
V,, and V,.. signifi-
cantly reduced in boys
smoking > 15 cigs/day
and girls smoking > 10
cigs/day, when
compared with NS.

smokers (99.5%
predicted) than in
nonsmokers (100.7%
predicted).

of spirometric data. *

significant reduc-
tion for FEV,.

mI oF

Age distribution -
not given; no -<-".
adjustment for <2.
height in analysis

  

 

  

fee RRR. -
Age distribution

not given, non-
significant reduc-
tion for FEV,.

   

No definition of

smoker, nonsmoker;
tests of statistical
significance not
provided. —

 

*Listed chronologically by publication date.

*NS = never smoker; FEV, = forced expiratory volume in one second; VC = vital capacity; MEFV = maximal expiratory flov

volume; V,,

= flow rate at 50% of vital capacity; V,, = flow rate after exhalation of 75% of vital capacity; FVC = forced vital

capacity; PEFR = peak expiratory flow rate; FEF,, ., = forced expiratory flow from 25% to 75% of FVC.

Year not provided.

18 Health Consequences
Preventing Tobacco Use Among Young People

 

 

Table 2. Continued
Study
Reference Location/year population Findings* Comment
Backhouse 1975 United 195 boys ata PEFR on arrival None
Kingdom? detention center, dropped significantly
mean age = 18 years with daily smoking

 

 

 

_ Collier 1979

Australia,
1971-1980

Woolcock et al.
1979

10,898 school
children, mean ages
= 8.9 years for
primary school and
12.6 years for high
school groups

amount; significant
improvement during
8-week stay while
unable to smoke

ery

  
 
 

No overall effect of
smoking on spiromet-
ric values in 1974
data; decreased lung
growth in smoking
boys who had had
bronchitis before age

See text for review

of longitudinal
findings.

 

Kujala 1981 Finland, 1976

1,075 male military
recruits, mean age =
20 years

Significantly reduced
FEV, and spirometric
flows when comparing
NS with smokers at
interview.

 

 

19

Health Consequences
from the findings from cross-sectional studies. Beck,
Doyle, and Schachter (1982) examined white residents
of Lebanon, Connecticut, in 1972 and 1978. Among
male and female subjects aged 15 through 24 in 1972,
smoking had reduced the increment of FEV, during the
six-year follow-up interval.

Ina 10-year study in Sydney, Australia, Woolcock
et al. (1984) periodically measured lung function in an
initial cohort of 11,497 schoolchildren. Two groups of
children were included: a younger cohort that was 8.9
years of age on average at enrollment and an older
cohort aged 12.6 years on average at enrollment. The
investigators followed up the cohort annually, measur-
ing respiratory function and assessing symptoms, ill-
nesses, and smoking. A small number of children were
studied more intensively with the single-breath nitro-
gen test. The effect of smoking was examined only in
the older cohort. Cross-sectional assessment of these
data showed that at 50 percent of vital capacity, smok-
ers tended to have lower maximal expiratory flow than
nonsmokers. For example, adolescents who smoked at
least 10 cigarettes per week had about a 5 percent lower
expiratory flow rate than nonsmokers. The investiga-
tors concluded that abnormalities attributable to smok-
ing were found in adolescents as young as age 14 and as
soon as one year after beginning to smoke at least 10
cigarettes per week. They also concluded that smoking
was more harmful for children and adolescents who
had a history of respiratory illness, particularly asthma.

A cohort study of children in East Boston, Massa-
chusetts, has been informative on the effects of passive
and active smoking on lung function (Tager et al. 1979,
1983, 1985, 1988). In 1974, the study enrolled a cohort of
children aged five through nine who were sampled
from schools in East Boston. The families of these
children were then invited to participate in the initial
survey and in periodic follow-up examinations that
included a respiratory questionnaire and spirometry.

Several relevant longitudinal analyses of the East
Boston data have been reported (Tager et al. 1985, 1987,
1988). Using data from the first seven follow-up ex-
aminations, Tager et al. (1985) described the effect of
smoking on the growth rates of FEV, and on forced
expiratory flow (FEF) from 25 to 75 percent of forced
vital capacity (FEF.,, ,.) in a group of 669 subjects aged 5
through 19 years at enrollment. Using a Markov-type
autoregressive model, researchers found significant ef-
fects of smoking on both measures of lung function.
The model predicted that a child’s smoking, beginning
at age 15 and continuing through age 20, would reduce
FEV, to 92 percent of the expected value and FEF,, ,. to
90 percent of the expected value. A subsequent analysis

20 Health Consequences

Surgeon General's Report

using a nonparametric curve-smoothing method on
these same data showed that male smokers had a smaller
increase of FEV, at the end of the growth phase (a
suggestion of a lower maximum lung function) than
males who had not smoked; those who continued to
smoke into early adulthood also showed no evidence of
the plateau observed in never smokers before lung func-
tion began to decline. Similar findings were reported
for females.

Relevant information is also available from a com-
munity population study in Tucson, Arizona (Lebowitz
and Holberg 1988). The Tucson cohort was derived
from a population sample of 325 non-Hispanic white
residents, originally sampled in 1972 when they were
an average age of 8.8 years. Like the East Boston study,
the Tucson study was directed primarily at passive
smoking but also gathered information on active smok-
ing by measuring FEV, and FEF.,, ... The Tucson study
found effects of comparable magnitude with those ob-
served in the East Boston study. Although these effects
did not reach statistical significance in the Tucson data,
they were in the same direction as those from East
Boston, and the sample population was only half the
size.

Sherrill et al. (1992) examined the longitudinal
effects of active and passive smoking on lung function
in a cohort of New Zealand children observed from
ages 9 through 15. Active smoking did not have statis-
tically significant effects on FEV,, vital capacity, or
FEV, /vital capacity (percent), but the numbers of regu-
lar smokers were small. By age 15, 43 percent reported
occasional smoking (during the last year but not every
day), but only 10 percent were daily smokers (smok-
ing any number of cigarettes on a daily basis).

Jaakkola et al. (1991) carried out an eight-year
longitudinal study of lung function ina cohort of young
adults aged 15 through 40 at enrollment. Of 1,044
enrolled, 391 were subsequently followed. Smoking
was found to havea significant effect on change in FEV,
during the study period, but the results were not re-
ported by age interval.

Respiratory Morbidity

In adults, smoking is associated with increased
morbidity, as indexed by such measures as use of out-
patient medical services and absenteeism from work,
and with increased respiratory morbidity, as indexed
by frequency or severity of respiratory infections
(USDHHS 1990). Because smoking has been shown to
alter immune and inflammatory responses (U.S. De-
partment of Health, Education, and Welfare [USDHEW]
1979b), these effects on an individual's defenses could
preventing Tobacco Use Among Young People

plausibly lead to increased frequency and severity of
respiratory infections in smokers.

Studies involving a wide age range of young

le indicate that smoking increases respiratory mor-
bidity (Table 3). A number of these studies compared
medical care by smokers and nonsmokers in settings
where all medical care was obtained at a single clinic. In
one of the earliest studies, Haynes, Krstulovic, and Bell
(1966) examined the numbers of diagnoses for respira-
torv tract illnesses among male students (aged 14-19
years) at a preparatory school. Nearly half of the stu-
dents were smokers. All respiratory illnesses were
more common in the smokers; the increase was greatest
for the illnesses considered “severe.” The findings of
studies involving student nurses (Parnell, Anderson,
Kinnis 1966) and military cadets (Finklea et al. 1971)
were similar.

A series of studies have included military recruits
as subjects (Table 3); their ages ranged from 18 through
22. In the study of Pollard et al. (1975), the rates of
respiratory diagnoses were not significantly different
between smokers and nonsmokers. In the more recent
study of military recruits by Blake, Abell, and Stanley
(1988), self-report of smoking was associated with in-
creased risk for diagnosis of an upper respiratory tract
infection during a 13-week basic training period. Kark
and Lebiush (1981) and Kark, Lebiush, and Rannon
(1982) examined attack rates for influenza and influ-
enza-like illnesses in Israeli military recruits and found
that smoking was associated with an increased attack
rate in both male and female recruits.

Recently, in a study that examined’ adolescents
and young adults who had sickle cell anemia, Young et
al. (1992) found a strong relationship between cigarette
smoking and acute chest syndrome. In sickle cell ane-
mia patients, acute chest syndrome is characterized by
fever, cough, chest pain, leukocytosis, and pulmonary
infiltrates in the chest radiograph. All smokers in this
study had a history of acute chest syndrome, whereas
65 percent of the nonsmokers did. Smoking also ap-
peared to increase the frequency of sequelae of sickle
cell lung disease.

A study in the United Kingdom (Charlton and
Blair 1989) associated smoking with increased absen-
teeism from school among 2,885 children aged 12 and
13 years. Children who on an initial questionnaire
reported regular smoking were more likely than non-
smokers to be absent when a follow-up questionnaire
was administered four months later. The authors inter-
preted these findings as showing a higher rate of minor
ailments in children who smoked; however, the design
could not exclude other plausible explanations (such as
truancy) for the difference. In a survey of adolescents

invited for an overall evaluation in three general prac-
tices in the United Kingdom, smokers reported a higher
prevalence of health problems than nonsmokers (25
percent vs. 16 percent, p = .06) (Townsend et al. 1991).

Epidemiologic Evidence of Nonrespiratory
Effects

Cardiovascular Disease

In adults, cigarette smoking is a cause of coronary
heart disease, arteriosclerotic peripheral vascular dis-
ease, and stroke (USDHHS 1989). Although these
diseases rarely occur in children and adolescents, au-
topsy studies of young male victims of combat during
the Korean and Vietnam conflicts and community-based
autopsy studies of adolescents and young adults have
shown that atherosclerosis begins in childhood and
may become clinically significant in young adulthood
(McNamara etal. 1971; Enos, Holmes, Beyer 1986; Strong
1986).

Several autopsy-study series link cigarette smok-
ing to the occurrence and extent of atherosclerosis in
young adults. Strong and Richards (1976) described the
association of cigarette smoking with atherosclerosis in
1,320 men from the New Orleans area. In the youngest
group (aged 25 to 34 years), the development of athero-
sclerosis in the coronary arteries and the abdominal
aorta was consistently greater with higher levels of
smoking.

More recently, an eight-community study by the
Pathobiological Determinants of Atherosclerosis in
Youth (PDAY) Research Group (1990) found associa-
tions of smoking with atherosclerosis in 390 males aged
15 through 34 years who died of violent causes (e.g.,
accidents, homicides, suicides). In this study, lipids
were measured in postmortem serum, and smoking
was assessed by the level of serum thiocyanate. After
controlling for lipid levels, age, and race, a multiple
regression analysis revealed a significant association
between smoking and atherosclerosis (i.e., having raised
lesions greater than or equal to 5 percent of the intimal
surface area) in the abdominal aorta. A multiple logistic
analysis controlling for the same factors found that
smoking was a significant predictor of atherosclerosis
in both the abdominal aorta and the right coronary
artery.

The Bogalusa Heart Study is an epidemiologic
study of cardiovascular disease risk factors encountered
from birth through age 26. Among deceased subjects
whose average age was 18 years, cigarette smoking was
not associated with aortic fatty streaks or involvement of
the coronary arteries with atherosclerosis (Newman et
al. 1986; Freedman etal. 1988). However, in subjects who

Health Consequences 21
Surgeon General's Report

Table 3. Published studies of the effects of smoking on respiratory morbidity among young people,
various countries, 1963-1987

 

 

Reference* _ Location/year Study population
Haynes, Krstulovic, Bell 1966 New Jersey’ 191 male prep school students
aged 14-19 years

   
 

 

oe Boe eam gitg Lede REET

Parnell, Anderson, Kinnis 1966 a Canada, 1963-1964

  
  

 
 

 

Finklea et al. 1971 South Carolina, 1968-1969 1,900 college students

 

 

 

 

 

Israel, 1979 Female military recruits,
mean age = 18.5 years

 
  
    
    

arene

 

ade ~ Pies dnt ene

Blake, Abell, Stanley 1988 Georgia, 1982 1,230 Army recruits,
most aged < 22 years

Tee cae

   

ne ESO NE RE TEN AEE EIT EF

> Charlton and Blair 1989

sae

   
   

 

Schwartz and Zeger 1990 California’ 100 student nurses

 

*Listed chronologically by publication date.
tYear not provided.

22 Health Consequences
preventing Tobacco Use Among Young People

 

Health effect | Prevalence (%) by smoking status
Nonsmoker Occasional smoker* Regular smoker®

Annual illness rates*/ 10 students .
16.0 22.0

All respiratory 11.0 .
Severe respiratory 1.4 3.6 5.4

  

 

 

All respiratory ©.)
Upper respiratory .
Lower respiratory
Number of cigarettes smoked per day
0 <1 pack >I pack
Incidence rate** (per 100 school years)
Upper respiratory
Outpatient 52.5 59.9 67.0
Hospital 7.6 12.0 10.2
Lower respiratory
Outpatient 2.5 3.0 6.8
0.4 0.7 0.9

Hospital

  

 

- Leb cho neath

General Findings: Relative risk = 1.46 for upper respiratory infection for smokers versus nonsmokers. Illnesses
cc ieamiaa | by visits to clinics.

  
 
 

General Findings: Smoking associated with increased absence f
and 3.09 for regular smokers (compared w with never smokers). '

General Findings: Smoking significantly associated with incidence of cough and phlegm. Current amount smoked
significantly predicted duration of an episode of phlegm or chest discomfort.

*Smoked at least 1 cigarette or pipe per week. *Respiratory-related (similar symptoms) visits to dispensary,
with one week grouped.

HBased on self-administered questionnaire.

These categories were not defined.

4Tliness occurrence based on medical records and serology.

“Smoked at least 1 cigarette or pipe per day.

uiness rates based on infirmary visits during a school year.
[ness incidence based on records of the health service.

**Incidence rates based on self-administered questionnaire.

Health Consequences 23
died after age 20, smoking appears to have been related
to atherosclerosis (Berenson et al. 1992).

Smoking among young people has been associated
with serum lipid profiles in a pattern predictive of in-
creased risk for cardiovascular diseases. In a published
meta-analysis of studies on children who smoke, Craig
et al. (1990) found that among 8- through 19-year-olds,
smoking increased levels of low-density lipoprotein cho-
lesterol by 4 percent, triglycerides by 12 percent, and
very-low-density lipoprotein cholesterol by 12 percent.
Levels of high-density lipoprotein (HDL) cholesterol were
reduced by 9 percent. These changes were comparable
to—and of larger magnitude than—those observed in
smoking adults.

Physical Fitness

Even among young people trained as endurance

runners, smoking appears to compromise physical -

fitness in levels of both performance and endurance.
Cigarette smoking reduces the oxygen-carrying capacity
of the blood and increases both heart rate and basal
metabolic rate—changes that counter the benefits of physi-
cal activity in a direct relation to the duration of smoking
and the number of cigarettes regularly smoked (Royal
College of Physicians of London 1992). Ina study of 19-
year-old army conscripts (N = 6,500), those who smoked
ran a significantly shorter distance in 12 minutes and
took significantly longer to sprint 80 meters than their
nonsmoking counterparts (Marti et al. 1988). In the same

study, the smokers among 4,100 joggers ina 16-kilometer’

race were consistently slower than the nonsmokers.

Young adult smokers also have chronic, mild ad-
verse cardiovascular physiologic changes, including di-
minished exercise performance on standard treadmill
testing and blunted heart rate response to exercise (Sidney
et al. 1993). The left ventricular mass is increased in
young adult smokers, and their resting heart rates are
two to three beats per minute more rapid than nonsmok-
ers’ (Gidding et al. 1992).

Health Outcomes in Pregnancy

Cigarettesmoking during pregnancy has been linked
witha variety of adverse outcomes (USDHHS 1989, 1990).
Early reports of the Surgeon General (USDHEW 1971,
1973, 1979a) concluded that smoking by a mother during
pregnancy retards fetal growth and may cause fetal death
late in pregnancy as well as infant mortality. The 1977-
1978 report (USDHEW 1979a) further concluded that
smoking during pregnancy has dose-response relation-
ships with abruptio placenta, placenta previa, bleeding
during pregnancy, premature and prolonged rupture
of placental membranes, and preterm delivery. The

24 Health Consequences

Surgeon General's Report

comprehensive reviews of the 1979 and 1980 reports
(USDHEW 1979a; USDHHS 1980) concluded that the risk
of spontaneous abortion increases with the amount of
smoking and that therisk of sudden infant death syndrome
(SIDS) is increased by maternal smoking. A more recent
study confirms the increased risk of SIDS with maternal
smoking (Schoendorf and Kiely 1992). Impaired fertility
was linked to smoking in the 1980 report (USDHHS 1980).
These adverse health effects of smoking on reproduction
have not been specifically investigated in young women in
the 10- through 20-year age range.

Epidemiologic Evidence of the Health Effects
of Passive Smoking

The health effects of passive smoking were com-
prehensively addressed in the 1986 report of the Surgeon
General (USDHHS 1986a) and ina report of the National
Research Council (1986). These reviews and subsequent
reports (Samet, Cain, Leaderer 1991; USEPA 1992) have
demonstrated that exposure to parental smoking during
childhood significantly increases the occurrence of lower
respiratory illnesses during the first years of life, in-
creases the frequency of chronic respiratory symptoms,
and reduces the rate of lung growth during childhood
and adolescence. Evidence is accumulating to suggest
that smoking by parents increases the severity of child-
hood asthma (USDHHS 1991b; Samet, Cain, Leaderer
1991), as indicated by the need for medication and hospi-
tal treatment. SIDS, the most common cause of death in
the first year of life, has been linked to parental smoking
in several epidemiologic studies. Children of parents
who smoke have a twofold increased risk of dying of
SIDS; this relationship appears to be dose-related
(Schoendorf and Kiely 1992; Malloy et al. 1988).

The evidence on passive smoking and respiratory
health was recently reviewed by the USEPA (1992). This
review confirmed that ETS is causally linked to lung
cancer. Janerich et al. (1990) noted that approximately 17
percent of lung cancers among nonsmokers can be attrib-
uted to high levels of ETS during childhood and adoles-
cence. The USEPA report also concluded that exposure
to ETS causes lower respiratory illness in infants and
young children; this finding is stronger than that of the
1986 Surgeon General's report, which did not character-
ize this association as causal. The agency’s report also
inferred from its data that childhood exposure to ETS
reduced lung function, increased respiratory symptoms,
caused middle ear effusion, and exacerbated asthma.
For example, the report estimated that ETS exposure
exacerbates symptoms of asthma in about 20 percent of
the two million to five million asthmatic children in the
United States. The report also hypothesized that ETS
may be associated with the onset of asthma.
preventing Tobacco Use Among Young People

Many chronic changes in cardiovascular physiol-
ogy have been observed in children exposed to ETS.
These changes include lower HDL cholesterol, increased
carboxyhemoglobin concentration, and increased
red-cell 2.3-diphosphoglycerate, as well as physiologic
" response suggesting mild, chronic hypoxemia

(Moskowitz et al. 1990). ETS is also known to increase
platelet aggregation (Glantz and Parmley 1991).

The effect of peer smoking—as a source of ETS—
on nonsmoking children has not been studied but may
also be a health risk.

Adult Health Implications of Smoking Among Young People

 

Respiratory Diseases

As was discussed previously, sustained smoking
during adulthood is associated with the development of
COPD and the progressive loss of lung function
(USDHHS 1984, 1990). Evidence suggests that smoking
during childhood may increase the risk for developing
COPD in adulthood as well as at an earlier age. The
adult who smoked during childhood may have experi-
enced early inflammatory changes—childhood smoking
is known to reduce lung growth—and thereby not at-
tained the level of function achieved during the normal
growth and development of the lungs. Any age-related
decline in lung function during adulthood would thus
start from a lower level—and might begin at a younger
age—than declines observed in adults who have never
smoked. In fact, the proportionate impeding effect of
childhood smoking on lung growth greatly exceeds the
loss of lung function associated with smoking during
adulthood (Tager et al. 1985, 1988).

If one or both parents of an adolescent smoke, the
effects of parental smoking on early childhood respira-
tory illnesses and on the growth of lung function may
increase the risk of COPD. Illnesses in the lower respira-
tory region during childhood are a suspected risk factor
for COPD (Samet, Tager, Speizer 1983), and passive
smoking reduces the rate at which lung function
grows (USDHHS 1986a).

Cardiovascular Disease

In adults, cigarette smoking has been causally
associated with coronary heart disease, arteriosclerotic
peripheral vascular disease, and stroke (USDHHS 1983,
1989). Smoking contributes to increased risk for coro-
nary heart disease probably through at least five in-
terrelated processes, including the development of
atherosclerosis (USDHHS 1990). It is likely that the
earlier the age at which one starts to smoke, the earlier
the onset of coronary heart disease. The recent evidence

from the PDAY Research Group shows more athero-
sclerosis in young smokers than in young nonsmokers.
The unfavorable effects of smoking on lipid levels in
children may contribute to the development of athero-
sclerosis in young adulthood.

Cancer

The multistage concept of carcinogenesis implies
that the risk of smoking-related cancers is strongly de-
pendent on the duration and intensity of smoking
(Armitage and Doll 1954; Doll 1971; Taioli and Wynder
1991). The relevant epidemiologic data and mathemati-
cal analyses are most abundant for lung cancer. Both
epidemiologic and experimental evidence suggest that
the risk for lung cancer varies more strongly with the
duration of cigarette smoking than with the number of
cigarettes smoked (Peto 1977; Doll and Peto 1978). Analy-
sis of data from a cohort study of British doctors showed
that lung cancer incidence increased with the fourth or
fifth power of duration of smoking but with the second
power of number of cigarettes smoked daily (Doll and
Peto 1978). Although these data can be adequately de-
scribed by alternative mathematical models that give
lesser weight to duration (Moolgavkar, Dewanji, Luebeck
1989), the dependence of lung cancer risk on duration of
smoking implies that starting smoking at an earlier age
increases the potential number of life-years of smoking
and therefore increases lung cancer risk. If one assumes,
for example, that lung cancer risk rises exponentially as a
function of the duration of smoking, then the risk at age
50 for a person who began smoking regularly at age 13 is
350 percent greater than that for a 50-year-old who started
smoking at age 23.

Similar analyses have not been done for other
smoking-related sites of cancer. Nevertheless, for
most smoking-related cancers, the risk rises with the
duration of smoking (USDHHS 1982, 1989, 1990; Interna-
tional Agency for Research on Cancer 1985). One could

Health Consequences 25