If rational individuals pay the full costs of their decisions about food intake and exercise, economists, policy makers, and public health officials should treat the obesity epidemic as a matter of indifference. In this paper, we show that, as long as insurance premiums are not risk rated for obesity, health insurance coverage systematically shields those covered from the full costs of physical inactivity and overeating. Since the obese consume significantly more medical resources than the non-obese, but pay the same health insurance premiums, they impose a negative externality on normal weight individuals in their insurance pool.

To estimate the size of this externality, we develop a model of weight loss and health insurance under two regimes——(1) underwriting on weight is allowed, and (2) underwriting on weight is not allowed. We show that under regime (1), there is no obesity externality. Under regime (2), where there is an obesity externality, all plan participants face inefficient incentives to undertake unpleasant dieting and exercise. These reduced incentives lead to inefficient increases in body weight, and reduced social welfare.

Using data on medical expenditures and body weight from the National Health and Interview Survey and the Medical Expenditure Panel Survey, we estimate that, in a health plan with a coinsurance rate of 17.5%, the obesity externality imposes a welfare cost of about $150 per capita. Our results also indicate that the welfare loss can be reduced by technological change that lowers the pecuniary and non-pecuniary costs of losing weight, and also by increasing the coinsurance rate.

Objective: Relatively little is known about the intergenerational mechanisms that lead to social disparities in child health. We examined whether the association between low socioeconomic status (SES) and child behavior problems is mediated by maternal health conditions and behavior.

Methods: Prospective cohort data (1979-1998) on 2,677 children and their mothers were obtained from the National Longitudinal Survey of Youth. SES, the Child Behavior Problems Index (BPI), and maternal smoking, depressive symptoms, and alcohol use before, during, and after pregnancy were examined.

Results: Lower income and lower maternal education were associated with increased child BPI scores. Adjustment for maternal smoking, depressive symptoms, and alcohol use attenuated the associations between SES and child BPI by 26% to 49%. These maternal health conditions often occurred together, persisted over time, and were associated with the mother's own childhood SES and pre-pregnancy health.

Conclusions: Social disparities in women's health conditions may help shape the

likelihood of behavior problems in the subsequent generation. Improved public

health programs and services for disadvantaged women across the lifecourse may

not only address their own urgent health needs, but reduce social disparities in the health and well-being of their children.

We compared the cost-effectiveness of a free nicotine replacement therapy (NRT) program with a statewide smoke-free workplace policy in Minnesota. We conducted 1-year simulations of costs and benefits. The number of individuals who quit smoking and the quality-adjusted life years (QALYs) were the measures of benefits. After 1 year, a NRT program generated 18,500 quitters at a cost of 7020 dollars per quitter (4440 dollars per QALY), and a smoke-free workplace policy generated 10,400 quitters at a cost of 799 dollars per quitter (506 dollars per QALY). Smoke-free work-place policies are about 9 times more cost-effective per new nonsmoker than free NRT programs are. Smoke-free workplace policies should be a public health funding priority, even when the primary goal is to promote individual smoking cessation.

Background: An increase in the incidence of esophageal adenocarcinoma has coincided with a decrease in the prevalence of Helicobacter pylori infection. Whether these 2 phenomena are associated is unknown.

Methods: We conducted a nested case-control study of 128,992 members of an integrated health care system who had participated in a multiphasic health checkup (MHC) during 1964-1969. During follow-up, 52 patients developed esophageal adenocarcinoma. Three randomly chosen control subjects from the MHC cohort were matched to each case subject, on the basis of age at the MHC, sex, race, and the date and site of the MHC. Data on cigarette smoking, alcohol consumption, body mass index (BMI), and education level were obtained at the MHC. Serum samples collected at the MHC were tested for IgG antibodies to H. pylori and to the H. pylori CagA protein.

Results: Subjects with H. pylori infections were less likely than uninfected subjects to develop esophageal adenocarcinoma (odds ratio [OR], 0.37 [95% confidence interval (CI), 0.16-0.88]). This significant association was restricted to case subjects and control subjects 50 years old at the MHC (OR, 0.20 [95% CI, 0.06-0.68]). In patients with H. pylori infections, the OR for those who tested positive for IgG antibodies to the CagA protein was similar to that for those who tested negative for it. BMI >/=25 and cigarette smoking were strong independent risk factors for development of esophageal adenocarcinoma.

Conclusion: The absence of H. pylori infection, independent of cigarette smoking and BMI, is associated with a markedly increased risk of development of esophageal adenocarcinoma.

Mortality rates in the United States fell more rapidly during the late nineteenth and early twentieth centuries than in any other period in American history. This decline coincided with an epidemiological transition and the disappearance of a mortality "penalty" associated with living in urban areas. There is little empirical evidence and much unresolved debate about what caused these improvements, however. In this article, we report the causal influence of clean water technologies -- filtration and chlorination -- on mortality in major cities during the early twentieth century. Plausibly exogenous variation in the timing and location of technology adoption was used to identify these effects, and the validity of this identifying assumption is examined in detail. We found that clean water was responsible for nearly half the total mortality reduction in major cities, three quarters of the infant mortality reduction, and nearly two thirds of the child mortality reduction. Rough calculations suggest that the social rate of return to these technologies was greater than 23 to 1, with a cost per person-year saved by clean water of about $500 in 2003 dollars. Implications for developing countries are briefly considered.

Background:

The withdrawal of rofecoxib has highlighted concerns regarding the safety of cyclooxygenase-2 (COX-2) inhibitors. In some patients COX-2 inhibitors may be safer than nonselective nonsteroidal anti-inflammatory drugs (NSAIDs); however, the public health benefit of COX-2 inhibitors depends on their use in patients at higher than normal risk from NSAIDs. We examined trends in COX-2 inhibitor use based on risk for adverse events from NSAIDs.

Methods:

We analyzed data from the National Ambulatory Medical Care Survey (1999-2002) and National Hospital Ambulatory Medical Care Survey (1999-2001), nationally representative surveys of community and hospital-based outpatient practices. The main outcome measure was the proportion of patient visits in which COX-2 inhibitors were prescribed, stratified by risk of adverse gastrointestinal (GI) events from NSAIDs.

Results:

Of the visits in which either a COX-2 inhibitor or NSAID was prescribed, the frequency of COX-2 inhibitor use increased from 35% (1999) to 55% (2000) to 61% (2001 and 2002). Among patients with the lowest risk for adverse events from NSAIDs, the proportion receiving a COX-2 inhibitor increased from 12% in 1999 to 35% in 2002. Overall, increases in COX-2 inhibitor use among patients in whom NSAIDs could be used accounted for more than 63% of the growth in COX-2 inhibitor use during the period examined.

Conclusions:

Marked increases in COX-2 inhibitor use have occurred since their release, primarily among patients at low risk for adverse events from NSAIDs. These findings demonstrate the challenge of limiting innovative therapies to the settings in which they are initially targeted and maximally beneficial.

PURPOSE:

The cost-effectiveness of cardiopulmonary resuscitation (CPR) and defibrillation training for laypersons unselected for risk of encountering cases of cardiac arrest is not known. We compared the costs and health benefits of alternative resuscitation training strategies for adults without professional first-responder duties who are at average risk of encountering cases of out-of-hospital cardiac arrest.

METHODS:

We constructed a cost-effectiveness analytic model. Data on cardiac arrest epidemiology and the effectiveness of CPR/defibrillation training were obtained from the medical literature. Instructional costs were determined from a survey of training programs. Downstream cardiac arrest survivor quality-adjusted life expectancy and long-term health care costs were derived from prior studies. We compared three strategies for training unselected laypersons: CPR/defibrillation training alone, training combined with home defibrillator purchase, and no training. The main outcome measures were total instructional costs for trainees combined with health care costs for additional cardiac arrest survivors, and quality-adjusted survival for additional patients resuscitated by trainees.

RESULTS:

CPR/defibrillation training yielded 2.7 quality-adjusted hours of life at a cost of 62 US dollars per trainee (202,400 US dollars per quality-adjusted life-year [QALY] gained). Training laypersons in CPR/defibrillation with subsequent defibrillator purchase cost 2,489,700 US dollars per QALY. In contrast, CPR/defibrillation training cost less than 75,000 US dollars per QALY if trainees lived with persons older than 75 years or with persons who had cardiac disease, or if total training costs were less than 10 US dollars.

CONCLUSION:

Training unselected laypersons in CPR/defibrillation is costly compared with other public health initiatives. Conversely, training laypersons selected by occupation, low training costs, or having high-risk household companions is substantially more efficient.

Adolescent smokers (N = 211) were randomized to 1 of 2 groups: (a) nicotine patch plus bupropion SR (sustained release; 150 mg per day) or (b) nicotine patch plus placebo. Group skills training sessions were conducted each week by research staff. Abstinence rates at Weeks 10 and 26 were as follows: (a) patch plus bupropion, 23% and 8%, (b) patch plus placebo, 28% and 7%. Despite the lack of a treatment effect, a large majority of adolescents in both treatment groups reduced their consumption to a few cigarettes per day or less and maintained this reduction over time. Similarly, an examination of survival curves revealed that by the end of treatment many had managed to avoid a return to daily smoking. These findings are encouraging and suggest new avenues for research. For example, treatments of the kind examined in this report, augmented by extended maintenance therapies, may yield higher long-term success rates.