Objective

To assess the burden of mortality attributable to Alzheimer disease (AD) dementia in the United States.

Methods

Data came from 2,566 persons aged 65 years and older (mean 78.1 years) without dementia at baseline from 2 cohort studies of aging with identical annual diagnostic assessments of dementia. Because both studies require organ donation, ascertainment of mortality was complete and dates of death accurate. Mortality hazard ratios (HRs) after incident AD dementia were estimated per 10-year age strata from proportional hazards models. Population attributable risk percentage was derived to estimate excess mortality after a diagnosis of AD dementia. The number of excess deaths attributable to AD dementia in the United States was then estimated.

Results

Over an average of 8 years, 559 participants (21.8%) without dementia at baseline developed AD dementia and 1,090 (42.4%) died. Median time from AD dementia diagnosis to death was 3.8 years. The mortality HR for AD dementia was 4.30 (confidence interval = 3.33, 5.58) for ages 75-84 years and 2.77 (confidence interval = 2.37, 3.23) for ages 85 years and older (too few deaths after AD dementia in ages 65-74 were available to estimate HR). Population attributable risk percentage was 37.0% for ages 75-84 and 35.8% for ages 85 and older. An estimated 503,400 deaths in Americans aged 75 years and older were attributable to AD dementia in 2010.

Conclusions

A larger number of deaths are attributable to AD dementia in the United States each year than the number (<84,000 in 2010) reported on death certificates.

Thiazide diuretic agents lower the urinary excretion of calcium. Their use has been associated with increased bone density, but their role in preventing hip fracture has not been established. We prospectively studied the effect of thiazide diuretic agents on the incidence of hip fracture among 9518 men and women 65 years of age or older residing in three communities. At base line, 24 to 30 percent of the subjects were thiazide users. In the subsequent four years, 242 subjects had hip fractures. The incidence rates of hip fracture were lower among thiazide users than nonusers in each community; the Mantel-Haenszel relative risk of hip fracture, adjusted for community and age, was 0.63 (95 percent confidence interval, 0.46 to 0.86). The protective effect of the use of thiazides was independent of sex, age, impaired mobility, body-mass index, and current and former smoking status; the multivariate adjusted relative risk of hip fracture was 0.68 (95 percent confidence interval, 0.49 to 0.94). Furthermore, the protective effect was specific to thiazide diuretic agents, since there was no association between the use of antihypertensive medications other than thiazides and the risk of hip fracture. These prospective data suggest that in older men and women the use of thiazide diuretic agents is associated with a reduction of approximately one third in the risk of hip fracture.

Although smoking has been shown to be associated with excess morbidity and mortality, most studies have focused on young and middle-aged rather than elderly smokers. We examined the demographic characteristics and physical and psychological health of elderly cigarette smokers in four population-based studies (N = 3,673, 3,811, 2,811, and 4,165) of persons 65 years of age and older. Although there was substantial geographic variation in the percentages of smokers, the demographic and health characteristics of smokers were similar across the sites. Most women had never smoked, but most men were former or current smokers. The percentage of never smokers was highest in the "oldest old." Among the elderly ever smokers, men were more likely to have quit than women, and the relative percentage of former smokers increased with age. Current smokers were generally more likely to consume alcohol than never smokers. In this age group, cigarette smoking was typically associated with higher rates of physical disease and symptoms, poorer self-perceived health status, and higher levels of depressive symptoms. Based on these four large geographically diverse population surveys, cigarette smoking remains an important health burden and public health challenge among the elderly.

Background

Although cigarette smoking is the leading avoidable cause of premature death in middle age, some have claimed that no association is present among older persons.

Methods

We prospectively examined the relation of cigarette-smoking habits with mortality from all causes, cardiovascular causes, and cancer among 7178 persons 65 years of age or older without a history of myocardial infarction, stroke, or cancer who lived in one of three communities: East Boston, Massachusetts; Iowa and Washington counties, Iowa; and New Haven, Connecticut. At the time of the initial interview, prevalence rates of smoking in the three communities ranged from 5.2 to 17.8 percent among women and from 14.2 to 25.8 percent among men. During five years of follow-up there were 1442 deaths, 729 due to cardiovascular disease and 316 due to cancer.

Results

In both sexes, rates of total mortality among current smokers were twice what they were among participants who had never smoked. Relative risks, as adjusted for age and community, were 2.1 among the men (95 percent confidence interval, 1.7 to 2.7) and 1.8 among the women (95 percent confidence interval, 1.4 to 2.4). Current smokers had higher rates of cardiovascular mortality than those who had never smoked (as adjusted for age and community, the relative risk was 2.0 [95 percent confidence interval, 1.4 to 2.9] among the men and 1.6 [95 percent confidence interval, 1.1 to 2.3] among the women), as well as increased rates of cancer mortality (relative risk, 2.4 [95 percent confidence interval, 1.4 to 4.1] among the men and 2.4 [95 percent confidence interval, 1.4 to 3.9] among the women). In both sexes, former smokers had rates of cardiovascular mortality similar to those of the participants who had never smoked, regardless of age at cessation, whereas the rates for all cancers, as well as smoking-related cancers, remained elevated among men who had once smoked.

Conclusions

Our prospective findings indicate that the mortality hazards of smoking extend well into later life, and suggest that cessation will continue to improve life expectancy in older people.