Dwight B. Brock

Driving Life Expectancy of Persons Aged 70 Years and Older in the United States

OBJECTIVES We estimated total life expectancy and driving life expectancy of US drivers aged 70 years and older. METHODS Life table methods were applied to 4699 elderly persons who were driving in 1993 and reassessed in a 1995 survey. RESULTS Drivers aged 70 to 74 years had a driving life expectancy of approximately 11 years. A higher risk of mortality among men as a cause of driving cessation offset a higher risk of driving cessation not related to mortality among women that resulted in similar driving life expectancies. CONCLUSIONS Nationwide, many elderly drivers quit driving each year and must seek alternative sources of transportation. Because of differences in life expectancy, women require more years of support for transportation, on average, than men after age 70.

Prescription and nonprescription drug use among black and white community-residing elderly.

OBJECTIVES To examine and compare concomitants of prescription and nonprescription drug use of Black and White community-dwelling elderly. METHODS Information on prescription and nonprescription drug use, demographic and health characteristics, and use of health services was obtained from a probability-based sample of Black (n = 2152) and White (n = 1821) community-resident elderly in the Piedmont area of North Carolina. Descriptive statistics were calculated. Linear regression, in which sample weights and design effects were taken into account, was used for the final models. RESULTS For prescription drug use, 37% and 32% of the variance was explained for Whites and Blacks, respectively (6% and 5% for nonprescription drugs). Health status and use of medical services were the strongest predictors of prescription drug use for both races (with Medigap insurance also important for Whites and Medicaid important for Blacks). Demographic characteristics and self-assessed health were significant factors in the use of nonprescription drugs. Race independently predicted use of both types of drugs but explained only a small proportion of the variance. CONCLUSIONS Health status and use of health services are importantly related to prescription drug use. Non-prescription drug use is difficult to explain.

Demography and epidemiology of dying in the U.S. with emphasis on deaths of older persons.

As chronic disease continues to be the major cause of death and as the elderly population grows, it is important to evaluate the adequacy and completeness of health care strategies for the elderly. Two studies, the National Mortality Followback Survey and the National Institute on Aging Survey of the Last Days of Life, were designed to examine the circumstances of death for representative samples of decedents. Four areas of focus are location of death, transitions among health care settings, circumstances at the time of death, and changes in physical and cognitive function in the last year of life. Although the data are helpful for family planning, they are limited by a lack of data on costs.

Effect of age and severity of disability on short-term variation in walking speed: The women's health and aging study

Standardized objective measures of human performance have been introduced in clinical and epidemiologic studies of older populations. Reliability of these measures has usually been estimated by comparing two measures obtained in the same person. However, no information is available on variability of multiple measures collected serially over short time intervals. This study uses data from the Weekly Disability Study, a component of the Womens Health and Aging Study, to describe fluctuations in physical performance over multiple, consecutive time intervals. Walking speed was measured weekly over a 6-month period in 99 older women affected by mild to severe disability. Overall, 2120 observations were explored using techniques developed for the analysis of repeated measures. Results showed that the correlations between observations in the same person were inversely related to their separation in time. The decay in the autocorrelation function was steeper in the least disabled. However, even with 20-week separations in assessments, correlations remained above 0.6 in all age and severity of disability subgroups. Changes over time in performance differed somewhat between disability subgroups, but the relative performance across subgroups remained stable over the entire course of the study. A clear learning effect was found only in those in the middle disability subgroup. Results support the utilization of repeated measures of physical performance in research that evaluates older persons over time.

Prevalence and distribution of hip and knee joint replacements and hip implants in older Americans by the end of life

Background and aims: Hip and knee replacements have become increasingly common in the older population but the prevalence of these procedures and the potential impact on functioning towards the end of life have not been previously described. The aim of this study was to estimate the rates and distribution of hip and knee joint replacements and hip implants (surgical pins, screws, rods, plates, etc.) in people aged 65 and over who died in the US in 1993, and to measure mobility outcomes during their last year of life. Methods: Data were drawn from the 1993 National Mortality Followback Survey; 7684 deaths in people aged 65 years or over were included. From these data full informant interviews were available for 6586 (86%). Three hundred and forty-four decedents had hip joint replacements, 357 had hip implants, and 102 had knee joint replacements. Replicate methods were used to obtain weighted estimates for all decedents in the 1993 US base population. Results: Of female and male decedents, 15.5% (95% CI: 14.3–16.7) and 6.1% (95% CI: 3.9–8.2), respectively, had received the studied devices. About 80% of these had been implanted more than a year before death. There were large differences in the risks of receiving a hip joint replacement or a hip implant depending on gender, education and race. About 60% of recipients either had no difficulty in getting around their own homes during the last year of life or had difficulty lasting less than 6 months. Conclusions: Implanted hip and knee devices were common in older people who died in the US in 1993. Large sociodemographic differences in those who received vs those who did not were present at the end of life. While difficulty in walking is the main indication for joint replacements, a majority of those receiving replacements experienced less than 6 months of mobility difficulties in their own homes during the last year of their lives.

Trends in dementia mortality from two National Mortality Followback Surveys

The National Center for Health Statistics conducted National Mortality Followback Surveys (NMFS) in 1986 and 1993. The next-of-kin’s report of a physician’s diagnosis of AD before death and a listing of AD or other dementia as the underlying cause increased significantly among women but remained stable among men. Currently, AD is among the top 10 leading causes of death in elderly white men and women in the United States.

High-Density Lipoprotein Cholesterol and Vascular Stiffness at Baseline in the Activity Counseling Trial

In a middle-aged patient population, age was associated with stiffer vessels and high-density lipoprotein cholesterol with more elastic vessels. High-density lipoprotein cholesterol may be an indirect indicator of aerobic capacity or of less atherosclerosis, suggesting mechanisms for preserving vascular integrity.