Smoking is the leading cause of preventable disease and death in the United States. The health consequences of smoking impose a substantial economic toll on persons, employers, and society. Smoking accounts for $50 billion to $73 billion in annual medical-care expenditures, or 6% to 12% of all US medical costs. The costs associated with lost productivity are also extensive.
In 1997, approximately 25% of male and 27% of female active-duty Air Force personnel aged 17 to 64 years were smokers. A 1997 retrospective cohort study was conducted among Air Force personnel to estimate the short-term medical and lost productivity costs of current smoking to the US Air Force. This report summarizes the results of the study, which indicate that current smoking costs the Air Force approximately $107.2 million per year: $20 million from medical-care expenditures and $87 million from lost workdays.
Self-Reported Demographic Data
Study participants completed a health assessment survey and were followed for 1 year; researchers then calculated participants use of medical care and health-related lost work time (ie, time spent on smoking breaks, days spent in the hospital, and time away from duty station for outpatient clinic visits). Total expenditures among current smokers and never smokers were used to compute population-attributable fractions (ie, the fraction of expenditures attributable to active-duty Air Force members who currently smoked). Data were collected from 5,164 active duty TRICARE Prime enrollees aged 17 to 64 years in Arkansas, Louisiana, Oklahoma, and Texas who completed the Health Enrollment Assessment Review (HEAR) survey from September to December 1996, and who remained enrolled in the health plan the year following the HEAR survey.
The HEAR instrument is a voluntary survey given to all TRICARE Prime enrollees. Self-reported demographic data were obtained by written questionnaires from the Air Force personnel system; smoking status, weekly alcohol(Drug information on alcohol) consumption, frequency of aerobic exercise, and body mass index data also were obtained through self-administered questionnaires from HEAR (Table 1). Respondents were classified as current, former, or never smokers.(1) Results for former smokers were not included in this study. Inpatient and outpatient visits, clinical diagnoses, bed days, and encounter costs were obtained from the Corporate Executive Information System (CEIS) and the TRICARE Management Activity.
Estimates Based on Linear Interpolation
Prevalence estimates of all currently smoking active-duty Air Force personnel during 1997 were based on a linear interpolation of results from the 1995 and 1998 US Department of Defense Survey of Health Related Behaviors Among Military Personnel.(2) Prevalence estimates in the Department of Defense survey were 22% and 49% higher than those in HEAR among men and women, respectively. The Department of Defense survey of risk behaviors is anonymous and is assumed to reflect current smoking in the active-duty Air Force population more accurately than the HEAR survey, which is not anonymous.
An empirical model was used to compare medical-care expenditures and lost work time among current smokers and never smokers. Men and women were modeled separately because of the influence of pregnancy-related events. A log-linear Poisson regression model was used to compare the rates of accumulating medical-care costs. Sex-specific rate ratios were adjusted for age, race, weekly alcohol consumption, frequency of aerobic exercise, and body mass index. Adjusted rate ratios from HEAR were combined with current smoking prevalence data from the Department of Defense survey to estimate population-attributable fractions of expenditures associated with current smoking for all active-duty Air Force personnel. The use of two distinct datasets in the population-attributable fractions formula precluded computing confidence intervals.
The average margin of error (one-half the width of the confidence interval around the mean) was ± 3.6% for the rate ratio estimates and ± 4.1% for the prevalence estimates. The rate ratio margins of error and smoking prevalence estimates indicate the overall stability of the population-attributable fractions. Smoking-attributable expenditures among men and women were calculated by multiplying the population-attributable fractions by total medical-care costs for each sex.
Total medical-care costs for Air Force personnel were $347 million and were estimated by using CEIS data to extrapolate the sex-specific medical-care costs for the study cohort to the entire active-duty Air Force population. Productivity costs were estimated using 1996 age-specific and sex-specific salary and benefit data among Air Force personnel. Hospital days, outpatient clinic visit time, and excess break time for current smokers were included; nonhospital sick days were excluded.
Smoking-attributable medical-care costs for active-duty Air Force personnel were approximately $20 million (Table 1), representing approximately 6% of the total annual Air Force medical system expenditures. In 1997, current smoking was associated with 893,128 lost workdays: 739,374 among men and 153,755 among women. Assuming 250 workdays per year, this lost work time represents a loss of approximately 3,573 full-time equivalent positions in 1997: 2,957 among men and 615 among women. Lost workdays represent approximately $87 million in annual productivity losses: $76 million among men and $11 million among women.
Editorial Note From the CDC
Current smoking among active-duty Air Force personnel is associated with large medical expenditures and lost productivity each year, particularly among men. The 6% smoking-attributable portion of Air Force medical expenditures is within the 6% to 12% range of recent smoking-attributable expenditures estimated for total US medical costs.
The Department of Defense estimated that current smoking among all US military health system beneficiaries cost an estimated $930 million in 1995: $584 million in annual health-care expenditures and $346 million in lost productivity. Among active-duty Air Force personnel, smoking-attributable productivity losses were more than four times the cost of medical care: 6.7 times among women and 4.1 times among men. The number of lost full-time equivalent positions is larger than the number of full-time equivalent positions on active duty at 35 (40%) of 87 Air Force installations.
The findings in this report differ from previous cost-of-smoking estimates because the study population in this report excludes persons aged ³ 65 years; the costs for former smokers were excluded. Consequently, medical costs among this younger population are a much smaller percentage of total smoking-attributable costs than in other studies.[2,3]
The exclusion of results for former smokers also lowers the costs of smoking estimates for women compared with men. Pregnancy-related events were a large portion of health-care use among female active-duty Air Force personnel. Because a substantial proportion of women quit smoking during pregnancy and many others conceal their smoking status during pregnancy, the smoking-attributable expenditures population-attributable factors among women who are classified as current smokers may be artificially low; this may account for the lower costs of smoking for women relative to men. In 1993, smoking-attributable medical costs for the United States were approximately 51% lower for women than men.
Limitations of Findings
The findings in this report are subject to at least four limitations. First, the study cohort may not be representative of all active-duty Air Force personnel. Second, study participants knew their HEAR survey responses would become part of their medical record. This might have reduced the rate of self-reported smoking and other risk behaviors when compared with anonymous Air Force surveys; however, anonymity may be only one factor influencing differences in reported risk behaviors.
Third, the medical-care costs and productivity losses of former smokers were not included. Finally, the study excluded lost productivity on days that Air Force personnel were on convalescent leave or confined to quarters; a large number of work days may have been missed because of less severe illnesses that did not require hospitalization. The second, third, and fourth limitations may underestimate the costs of smoking among active-duty Air Force personnel.
These results support Air Force and Department of Defense efforts to decrease the prevalence of smoking among active-duty Air Force personnel. Smoking-attributable lost work time is particularly important for Air Force operational commanders because it adversely affects military readiness; however, the impact of smoking on productivity also is relevant to civilian employers.
The prevalence of smoking among active-duty Air Force members is approximately the same as among the US population aged 18 to 64 years. However, because of physical training requirements, smokers in the active-duty Air Force population are probably healthier than smokers in the civilian population. If so, average productivity losses to civilian employers could be larger than those found in this military group.
Costs related to tobacco use are largely preventable. Implementing comprehensive tobacco-control programs remains an effective way to reduce associated medical and productivity losses.
This Commentary was reported by the Office for Prevention and Health Services Assessment, Air Force Medical Operations Agency, Brooks Air Force Base, Texas and the Office on Smoking and Health, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control. Adapted from Morbidity and Mortality Weekly Report 49(20):441-445, 2000.