1 table omitted
Each year in the United States, approximately 440,000 persons die of
a cigarette smoking-attributable illness, resulting in 5.6 million years of
potential life lost, $75 billion in direct medical costs, and $82 billion
in lost productivity.1 To assess smoking-attributable morbidity,
the Roswell Park Cancer Institute, Research Triangle Institute, and CDC analyzed
data from three sources: the Behavioral Risk Factor Surveillance System (BRFSS),
the National Health and Nutrition Examination Survey III (NHANES III), and
the U.S. Census. This report summarizes the results of that analysis, which
indicate that an estimated 8.6 million persons in the United States have serious
illnesses attributed to smoking; chronic bronchitis and emphysema account
for 59% of all smoking-attributable diseases. These findings underscore the
need to expand surveillance of the disease burden caused by smoking and to
establish comprehensive tobacco-use prevention and cessation efforts to reduce
the adverse health impact of smoking.
Data on the number of persons by sex, age group (18-34 years, 35-49
years, 50-64 years, and ≥65 years), and race (white or other race) for
each state and the District of Columbia were obtained from the 2000 U.S. Census.
National estimates of the prevalence of current, former, and never smokers*
were derived from the combined data from the 1999, 2000, and 2001 BRFSS surveys.
Estimates of the prevalence of smoking-related conditions were obtained
from the NHANES III survey for 1988-1994 for current, former, and never smokers
for each demographic group to estimate the smoking-attributable fractions
of morbid conditions. The smoking-related conditions for which data were collected
are those categorized by the U.S. Surgeon General as caused by smoking2 and addressed in NHANES III. Respondents reported whether a "doctor
ever told" them if they had any of the following conditions: stroke, heart
attack, emphysema, chronic bronchitis, and specific cancer types, including
lung, bladder, mouth/pharynx, esophagus, cervix, kidney, larynx, or pancreas.
Smoking-attributable morbidity estimates were obtained in two ways. For one
estimate, each person was considered as the unit of analysis, and persons
with at least one smoking-related condition were counted as having a condition.
For the second estimate, the condition was treated as the unit of analysis,
so persons with multiple conditions were counted more than once. Estimates
were derived separately for each condition, and the total of all conditions
The number of persons with a smoking-attributable morbid condition was
estimated by state and demographic subpopulations from the following five
steps: (1) BRFSS smoking status estimates by demographic group were applied
to census data to estimate the number of current, former, and never smokers
in each demographic group in each state; (2) NHANES III smoking-related disease
frequency data were applied to the numbers from the first step to estimate
the number of adults with a smoking-related condition; (3) attributable fractions
for current and former smokers in each demographic group were multiplied by
the number of persons with a smoking-related disease to yield an estimate
of the number of persons with a disease that is attributable to smoking (attributable
fraction = [disease prevalence rateexposed – disease prevalence
rateunexposed]/disease prevalence rateexposed); (4)
the numbers obtained from the third step were summed across all demographic
categories in each state to yield an estimate of persons with smoking-attributable
conditions in each state; and (5) the numbers of smoking-attributable morbid
conditions obtained in each state from step four were summed to yield an overall
U.S. estimate. Survey design-adjusted variance estimates were calculated for
each smoking and disease prevalence by using SUDAAN. The variance estimate
for the attributable fraction was calculated by using standard methodology,3 and a joint 95% confidence interval (CI) was obtained for each attributable
fraction by using Bonferroni's adjustment method.4
In 2000, an estimated 8.6 million (95% CI = 6.9-10.5 million) persons
in the United States had an estimated 12.7 million (95% CI = 10.8-15.0 million)
smoking-attributable conditions. For current smokers, chronic bronchitis was
the most prevalent (49%) condition, followed by emphysema (24%). For former
smokers, the three most prevalent conditions were chronic bronchitis (26%),
emphysema (24%), and previous heart attack (24%). Lung cancer accounted for
1% of all cigarette smoking-attributable illnesses.
A Hyland, PhD, C Vena, J Bauer, PhD, Q Li, MS, GA Giovino, PhD, J Yang,
PhD, KM Cummings, PhD, Dept of Cancer Prevention, Epidemiology, and Biostatistics,
Roswell Park Cancer Institute, Buffalo, New York. P Mowery, MS, Research Triangle
Institute, Research Triangle Park, North Carolina. J Fellows, PhD, T Pechacek,
PhD, L Pederson, PhD, Office on Smoking and Health, CDC.
This report provides the first national estimates of the number of persons
with serious chronic illnesses caused by smoking and the total number of their
smoking-attributable conditions. The findings indicate that more persons are
harmed by tobacco use than is indicated by mortality estimates. Examining
trends in tobacco-attributable morbidity provides another way to monitor the
progress of tobacco-control efforts.
Smoking-attributable mortality estimates published in 20021 differ
from the estimates described in this report. Mortality data indicate the number
of persons who die of a disease each year, and morbidity data from this study
are used to estimate the prevalence of persons living with diseases caused
by smoking at a point in time. In addition, mortality estimates are based
on official cause of death data and smoking-attributable fractions derived
from data from the Cancer Prevention Study II, and the smoking-attributable
morbidity fractions in this study are based solely on self-reported survey
data on diseases addressed in NHANES III.
The findings in this report are subject to at least three limitations.
First, the estimates do not adjust for potential confounders (e.g., diet,
exercise, or geography) other than age, sex, and race/ethnicity. The impact
of confounding was examined in a prospective cohort study of approximately
one million persons; findings indicated that adjusting for several demographic,
behavioral, medical, and occupational factors reduced the smoking attributable
mortality estimate by only 2.5%. However, no analyses have been performed
that examine smoking-attributable morbidity or that use a broader range of
potential confounders.5 Second, disease data are self-reported
and might not represent the true rate or type of disease. A Canadian study
found that the rate of underreporting of the chronic conditions cancer, stroke,
and hypertension was approximately two times greater than the rate of overreporting.6 In addition, 63% of NHANES III respondents with documented low-lung
function (forced expiratory volume in 1 second was <80% of the predicted
value) did not self-report any diagnosis of obstructive lung disease.7 Therefore, these self-reported data are probably substantial underestimates
of a true disease burden. Finally, the scope of diseases considered in this
report was limited to those diseases for which survey data were available
and those the U.S. Surgeon General implicated smoking as the cause. Various
additional chronic and acute conditions affect quality of life and are caused
by cigarette smoking. Inclusion of additional diseases would increase the
amount of morbidity attributable to smoking.
The findings in this report complement CDC mortality data and estimates
of the number of adults with chronic diseases caused by smoking. Approximately
10% of all current and former adult smokers have a smoking-attributable chronic
disease. Many of these persons are already experiencing decreased quality
of life, and society will likely bear substantial direct and indirect economic
costs from these diseases.1 More persons will experience serious
chronic diseases attributable to smoking if they continue to smoke.8 This report underscores the need to expand the implementation of proven
strategies to reduce tobacco use such as increasing the cost of cigarettes,
increasing clean indoor air regulations, and implementing comprehensive tobacco-use–prevention
and cessation programs.
REFERENCES: 8 available
*Current smokers were defined as persons who reported smoking ≥100
cigarettes during their lifetime and who now smoke some days or every day.
Former smokers were defined as persons who reported having smoked ≥100
cigarettes during their lifetime but did not smoke at the time of interview.
Never smokers were defined as persons who reported having smoked <100 cigarettes
during their lifetime.
Cigarette Smoking-Attributable Morbidity— United States, 2000. JAMA. 2003;290(15):1987-1988. doi:10.1001/jama.290.15.1987