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.

Objectives

The study was designed to determine whether racial disparity in utilization of the implantable cardioverter-defibrillator (ICD) has improved over time, and whether small-area geographic variation in ICD utilization contributed to national levels of racial disparity.

Background

Although racial disparities in cardiac procedures have been well-documented, it is unknown whether there has been improvement over time. Low ICD utilization rates in predominantly black geographic areas may have exacerbated national levels of disparity.

Methods

Discharge abstracts from elderly black and white Medicare beneficiaries hospitalized with ventricular arrhythmias from 1990 to 2000 were analyzed to determine if ICD implantation occurred within 90 days of initial hospitalization. Multivariate logistic regression models were constructed to assess the relationship between ICD implantation, year of admission, and the percentage of black inhabitants in each patient's county of hospitalization while controlling for clinical, hospital, and demographic characteristics.

Results

There was improvement in ICD implantation racial disparity: In the period 1990 to 1992, black patients had an odds ratio of 0.52 (95% confidence interval [CI] 0.42 to 0.64) for receiving an ICD compared with whites. However, by 1999 to 2000, the odds ratio for blacks had risen to 0.69 (95% CI 0.61 to 0.78) (test-for-trend p = 0.01). Approximately 20% of this trend could be explained by reduction in geographic variation in ICD use between areas with larger black and predominantly white populations.

Conclusions

Rates of ICD implants became more equal among whites and blacks during the 1990s, although persistent disparity remained at the decade's end. Geographic equalization in cardiovascular procedure rates may be an essential mechanism in rectifying disparities in health care.

This issue of CHP/PCOR's quarterly newsletter covers news and developments from the fall 2004 quarter. It features articles about:

• the newly created Center on Advancing Decision Making for Aging (CADMA), a multidisciplinary research collaboration administered by CHP/PCOR that will explore how older Americans make decisions about their health and well-being;
• a roundtable discussion with healthcare and biotech industry leaders, sponsored by CHP/PCOR and led by Sean Tunis, MD, chief medical officer at the Centers for Medicare and Medicaid Services;
• groundbreaking research on the health needs and health status of China's elderly, conducted by trainees in CHP/PCOR's China-U.S. Health and Aging Research Fellowship;
• research by CHP/PCOR faculty and affiliates on racial disparities in the use of implantable cardioverter-defibrillators (ICDs), the drug industry's marketing of low-dose forms of hormone replacement therapy, and the long-term risks of surgery and anesthesia; and
• renewed funding and seed projects for CHP/PCOR's Center on the Demography and Economics of Health and Aging.

The traditional focus of disability research has been on the elderly, with good reason. Chronic disability is much more prevalent among the elderly, and it has a more direct impact on the demand for medical care. It is also important to understand trends in disability among the young, however, particularly if these trends diverge from those among the elderly. These trends could have serious implications for future health care spending because more disability at younger ages almost certainly translates into more disability among tomorrow's elderly, and disability is a key predictor of health care spending. Using data from the Medicare Current Beneficiary Survey (MCBS) and the National Health Interview Study (NHIS), we forecast that per-capita Medicare costs will decline for the next fifteen to twenty years, in accordance with recent projections of declining disability among the elderly. By 2020, however, the trend reverses. Per-capita costs begin to rise due to growth in disability among the younger elderly. Total costs may well remain relatively flat until 2010 and then begin to rise because per-capita costs will cease to decline rapidly enough to offset the influx of new elderly people. Overall, cost forecasts for the elderly that incorporate information about disability among today's younger generations yield more pessimistic scenarios than those based solely on elderly data sets, and this information should be incorporated into official Medicare forecasts.

Objective: To quantify the effects of informal caregiver availability and public funding on formal long-term care (LTC) expenditures in developed countries.

Data Source/Study Setting: Secondary data were acquired for 15 Organization for Economic Cooperation and Development (OECD) countries from 1970 to 2000. Study Design. Secondary data analysis, applying fixed- and random-effects models to time-series cross-sectional data. Outcome variables are inpatient or home heath LTC expenditures. Key explanatory variables are measures of the availability of informal caregivers, generosity in public funding for formal LTC, and the proportion of the elderly population in the total population.

Data Collection/Extraction Method: Aggregated macro data were obtained from OECD Health Data, United Nations Demographic Yearbooks, and U.S. Census Bureau International Data Base.

Principal Findings: Most of the 15 OECD countries experienced growth in LTC expenditures over the study period. The availability of a spouse caregiver, measured by male-to-female ratio among the elderly, is associated with a $28,840 (1995 U.S. dollars) annual reduction in formal LTC expenditure per additional elderly male. Availability of an adult child caregiver, measured by female labor force participation and full-time/part-time status shift, is associated with a reduction of $310 to $3,830 in LTC expenditures. These impacts on LTC expenditure vary across countries and across time within a country.

Conclusions: The availability of an informal caregiver, particularly a spouse caregiver, is among the most important factors explaining variation in LTC expenditure growth. Long-term care policies should take into account behavioral responses: decreased public funding in LTC may lead working women to leave the labor force to provide more informal care.

Objective: To determine whether health maintenance organizations (HMOs) attract enrollees who use relatively few medical resources and whether a simple risk-adjustment system could mitigate or eliminate the inefficiency associated with risk selection.

Data Sources: The first and second rounds of the Community Tracking Study Household Survey (CTSHS), a national panel data set of households in 60 different markets in the United States.

Study Design: We use regression analysis to examine medical expenditures in the first round of the survey between enrollees who switched plan types (i.e., from a non-HMO plan to an HMO plan, or vice versa) between the first and second rounds of the survey versus enrollees who remained in their original plan. The dependent variable is an enrollee's medical resource use, measured in dollars, and the independent variables include gender, age, self-reported health status, and other demographic variables.

Data Collection Methods: We restrict our analysis to the 6,235 non-elderly persons who were surveyed in both rounds of the CTSHS, received health insurance from their employer or the employer of a household member in both years of the survey, and were offered a choice of an HMO and a non-HMO plan in both years.

Principal Findings: We find that people who switched from a non-HMO to an HMO plan used 11 percent fewer medical services in the period prior to switching than people who remained in a non-HMO plan, and that this relatively low use persisted once they enrolled in an HMO. Furthermore, people who switched from an HMO to a non-HMO plan used 18 percent more medical services in the period prior to switching than those who remained in an HMO plan.

Conclusions: HMOs are experiencing favorable risk selection and would most likely continue to do so even if employers adjusted health plan payments based on enrollees' gender and age because the selection is based on enrollee characteristics that are difficult to observe, such as preferences for medical care and health status.

We all have a stake in the size of the physician workforce. With too few physicians, access to care will be compromised; with too many, there will be strong pressures to overconsume health services. Increasing the production of U.S.-trained physicians by expanding physical resources of medical schools and creating new residency and fellowship positions will be costly and will have delayed, long-lasting effects on the supply of physicians' services. According to those who believe that physicians increase the demand for their own services, every additional physician would generate added health care costs for the length of a career, which now averages about 30 years. These increased expenditures would dwarf the short-term costs of expanding our capacity to train physicians.

Because new graduates are a small fraction of the total physician workforce, the supply of physicians would change little in the short run, even if it were possible to expand the number of training positions instantly. In an article in this issue (1), Richard Cooper forcefully argues that this delay is an important reason to take immediate action to increase the production of physicians. He projects that the United States will have 200 000 fewer physicians than we need in 2020. We agree that demographic and economic trends could increase the demand for physician services in the coming years, but we also believe that his forecast contains far too many uncertainties to serve as the basis for taking immediate action. We think that Cooper's analysis does not take account of important factors that could change the need for large increases in physician supply. In this commentary, we discuss the potential roles of a healthier aging population, changes in government policy, new technology, physician-induced demand for health care, and changes in the price of health care.

OBJECTIVE: Although an increasing fraction of Medicare beneficiaries die outside the hospital, the proportion of total Medicare expenditures attributable to care in the last year of life has not dropped. We sought to determine whether disproportionate increases in hospital treatment intensity over time among decedents are responsible for the persistent growth in end-of-life expenditures.

DATA SOURCE: The 1985-1999 Medicare Medical Provider Analysis and Review (MedPAR) and Denominator files.

STUDY DESIGN: We sampled inpatient claims for 20 percent of all elderly fee-for-service Medicare decedents and 5 percent of all survivors between 1985 and 1999 and calculated age-, race-, and gender-adjusted per-capita inpatient expenditures and rates of intensive care unit (ICU) and intensive procedure use. We used the decedent-to-survivor expenditure ratio to determine whether growth rates among decedents outpaced growth relative to survivors, using the growth rate among survivors to control for secular trends in treatment intensity. Data Collection. The data were collected by the Centers for Medicare and Medicaid Services.

PRINCIPAL FINDINGS: Real inpatient expenditures for the Medicare fee-for-service population increased by 60 percent, from $58 billion in 1985 to $90 billion in 1999, one-quarter of which were accrued by decedents. Between 1985 and 1999 the proportion of beneficiaries with one or more intensive care unit (ICU) admission increased from 30.5 percent to 35.0 percent among decedents and from 5.0 percent to 7.1 percent among survivors; those undergoing one or more intensive procedure increased from 20.9 percent to 31.0 percent among decedents and from 5.8 percent to 8.5 percent among survivors. The majority of intensive procedures in the United States were performed in the more numerous survivors, although in 1999 50 percent of feeding tube placements, 60 percent of intubations/tracheostomies, and 75 percent of cardiopulmonary resuscitations were in decedents. The proportion of beneficiaries dying in a hospital decreased from 44.4 percent to 39.3 percent, but the likelihood of being admitted to an ICU or undergoing an intensive procedure during the terminal hospitalization increased from 38.0 percent to 39.8 percent and from 17.8 percent to 30.3 percent, respectively. One in five Medicare beneficiaries who died in the hospital in 1999 received mechanical ventilation during their terminal admission.

CONCLUSIONS: Inpatient treatment intensity for all fee-for-service beneficiaries increased between 1985 and 1999 regardless of survivorship status. Absolute changes in per-capita hospital expenditures, ICU admissions, and intensive inpatient procedure use were much higher among decedents. Relative changes were similar except for ICU admissions, which grew faster among survivors. The secular decline in in-hospital deaths has not resulted in decreased per capita utilization of expensive inpatient services in the last year of life. This could imply that net hospital expenditures for the dying might have been even higher over this time period if the shift toward hospice had not occurred.

OBJECTIVES: This study seeks to further characterize the role of exercise testing in the elderly for prognosis and diagnosis of coronary artery disease. BACKGROUND: Recent exercise testing guidelines have recognized that statements regarding the elderly do not have an adequate evidence-based quality because the studies they are based on have limitations in sample size and design. The Duke Treadmill Score has been recommended for risk stratification, but recent evidence has suggested that it does not function in the elderly.

METHODS: The study population consisted of male veterans (1872 patients >or=65 years; 3798 patients <65 years) who underwent routine clinical exercise testing with a mean follow-up of six years. A subset who underwent coronary angiography as clinically indicated (elderly, n = 405; younger, n= 809) were included. The primary outcome for all subjects was cardiovascular mortality with coronary angiographic findings as the outcome in those selected for angiography.

RESULTS: In survival analysis, exercise-induced ST depression was prognostic in both age groups only when cardiovascular death was considered as the end point. Peak metabolic equivalents were the most significant predictor for both age groups only when all-cause death was considered as the end point. New age-specific prognostic scores were developed and found to be predictive for cardiovascular mortality in the elderly. Moreover, in the angiographic subset of the elderly, a specific diagnostic score provided significantly better discrimination than exercise ST measurements alone. For any new score, there is a need for validation in another elderly population.

CONCLUSIONS: The mortality end point affected the choice of prognostic variables. This study demonstrates that exercise test scores can be helpful for the diagnosis and prognosis of coronary disease in the elderly.