Adjusting Mini-Mental State Examination scores for age and educational level to screen for dementia: correcting bias or reducing validity?

The question of whether Mini-Mental State Examination scores should be adjusted for age and educational levels to screen for dementia in clinical populations is reexamined in the results of a recent study supporting adjustment. If the criterion is to identify the most accurate screening procedure for each sociodemographic subgroup, the evidence indicates that the unadjusted scores are preferable. Other criteria might lead to different conclusions. The validities of some of these criteria are questionable because they have the flaw that they are easily satisfied by using random decision procedures.

The influence of spouse cognitive impairment on respondents' depressive symptoms: the moderating role of marital closeness

An earlier report documented that, in a community-dwelling sample of 317 older married couples, cognitive impairment in a wife was associated with depressive symptoms in her husband (Moritz, Kasl, and Berkman, 1989). No similar effects were found for wives. Here we examine the extent to which marital closeness moderates the impact of a spouse's cognitive impairment, the stability of influences over 3 years, and gender differences in the associations. Analyses of covariance, controlling for respondent risk factors and potential confounders in the spouse, showed that marital closeness moderated the impact of a wife's cognitive impairment, with husbands in close marriages affected more strongly than husbands in less close marriages. These effects held over 3 years. In addition, husbands became less depressed following the death of a severely impaired wife, whereas widowers whose wife had been unimpaired at baseline were more depressed. None of these effects were found for wives.

Neurological and psychiatric predictors of mortality in patients with Alzheimer disease in California

OBJECTIVE

To determine whether neurological and psychiatric symptoms predict survival time among patients with Alzheimer disease (AD) after adjusting for the influence of sociodemographic variables, health conditions, and dementia severity separately for men and women.

DESIGN

The sample consisted of 936 men and women diagnosed as having probable or possible AD at 1 of 7 Alzheimer's Disease Diagnostic and Treatment Centers throughout California from 1986 through 1990. Data on dementia severity, comorbid conditions, and demographic characteristics were collected at the time of AD diagnosis. Data on vital status and dates of death were obtained by linking the patient file to several administrative databases maintained by the California State and federal governments. The mean length of follow-up was 31 months. Data were analyzed with Kaplan-Meier survival curves and Cox proportional hazards models.

RESULTS

Men had shorter survival times than did women (log-rank test, 30.93, P < .001). Among men, but not women, survival times were negatively associated with selected neurological and psychiatric symptoms. Among women, but not men, a history of cardiovascular conditions was associated with poorer survival.

CONCLUSIONS

Patterns of survival and predictors of survival time among patients with AD differ by sex. Future studies of survival and progression of AD need to examine men and women separately.

Hospital controls versus community controls: differences in inferences regarding risk factors for hip fracture

In case-control studies using cases identified from persons admitted to hospitals, two types of controls are most often used: persons from the communities served by the hospitals and persons admitted to the same hospitals as those to which the cases were admitted. It is often unclear which is the more appropriate choice, and whether the use of one or the other type of control group will lead to biased conclusions. The purpose of the present analysis was to determine whether the choice of hospital controls versus community controls would influence conclusions regarding risk factors for hip fracture. Cases (n = 425), hospital controls (n = 312) and community controls (n = 454) were drawn from a case-control study of risk factors for hip fracture in women. Study participants were white and black women aged 45 years or older and living in New York City or Philadelphia, Pennsylvania, who were selected between September 1987 and July 1989. Using community controls but not hospital controls, investigators would have concluded that having a fall during the previous 6 months, current smoking, and moving during the previous year were associated with an increased risk of hip fracture. Associations of hip fracture risk with stroke and prior use of ambulatory aids were stronger using community controls, but associations with estrogen use and body mass index were not influenced by choice of control group. Community controls were quite similar to representative samples of community-dwelling elderly women, whereas hospital controls were somewhat sicker and more likely to be current smokers. The authors conclude that community controls comprise the more appropriate control group in case-control studies of hip fracture in the elderly.

Living arrangements, changes in living arrangements, and survival among community dwelling older adults

OBJECTIVES

This study examines whether living arrangements and changes in living arrangements are associated with survival among older community-dwelling adults, and whether differences in health status account for observed differences in survival.

METHODS

The sample consisted of 5085 persons aged 70 years or older who had participated in the Longitudinal Study of Aging in 1984 and 1986. Proportional hazards models were used to examine associations of survival time through 1990 with living arrangements in 1984 and with changes in living arrangements from 1984 to 1986.

RESULTS

Women who lived with someone other than a spouse at baseline or who changed from living with a spouse to living with someone other than a spouse were at greater risk of dying than women in other living arrangements, independent of health status or functioning. Among men, survival time was not generally associated with baseline living arrangements.

CONCLUSIONS

Older adults who live alone or who change from living with someone to living alone do not have an increased mortality risk. However, living with or changing to living with someone other than a spouse may be associated with increased mortality risk.

Evaluating Alzheimer's special care units: reviewing the evidence and identifying potential sources of study bias

Special Care Units (SCUs) for Alzheimer's disease have been proliferating in long-term care, but their effectiveness remains unproven. This review summarizes the published studies, presents and discusses the many potential sources of bias that pose special problems for SCU research, and proposes strategies for conducting and interpreting future outcome studies in this difficult research setting.

Cognitive functioning and the incidence of limitations in activities of daily living in an elderly community sample

Although it is well-known that cognitive impairment in the elderly is usually accompanied by limitations in activities of daily living (ADL), it is not known whether cognitive impairment predicts the onset of new ADL limitations. The purpose of this analysis was to determine whether poor scores on a brief measure of cognitive functioning at baseline (1982) would predict the onset of persistent limitations in ADL during the subsequent 3 years, in a probability sample of community-dwelling elderly persons living in New Haven, Connecticut, who were initially free of ADL limitations (n = 1,856). Cognitive functioning was assessed with Pfeiffer's Short Portable Mental Status Questionnaire. Persistent incident ADL limitations were defined as the onset of one or more ADL limitations after 1982, with no subsequent reports of zero ADL limitations. Compared with persons who scored zero to one errors on the Short Portable Mental Status Questionnaire at baseline, persistent, incident ADL limitations occurred more frequently in persons who scored four or more errors (odds ratio for males = 2.72, 95% confidence interval 1.36-5.43; odds ratio for females = 2.60, 95% confidence interval 1.52-4.44) after adjustment for the confounding effects of housing type, age, race, history of chronic health conditions, and incident health conditions. These results suggest that knowledge of scores on brief cognitive function tests can be used to forecast service needs and to develop intervention programs to prepare for the possible onset of ADL limitations.

Health behaviors and survival among middle-aged and older men and women in the NHANES I Epidemiologic Follow-up Study

BACKGROUND

Since the 1960s there has been a decline in mortality rates for older U.S. adults, suggesting the importance of examining the role of prevention and health promotion in improving the health and survival of older adults. Epidemiologic studies of age and gender differences in the impact of health behaviors on survival for older U.S. adults are needed to provide information for intervention and health promotion efforts for older Americans.

METHODS

We examined whether health behavior risk factors (smoking, drinking, physical activity, and body weight) for mortality vary by age and gender among 6,109 adults 45-74 years old in the National Health and Nutrition Examination Survey 1971-1975 (NHANES I) who were traced during the 1982-1984 NHANES I Follow-up Survey.

RESULTS

For middle-aged men (45-54 years old) and for older men (65-74 years old), both smoking and nonrecreational physical activity were predictors of survival time. Additionally, for older men, drinking and low body mass index were associated with shorter survival time. Among women, there was less consistency of associations across age groups. As with men, nonrecreational physical activity and low body mass index were associated with shorter survival among older women.

CONCLUSIONS

These findings suggest that health behaviors are associated with survival in older adults as well as in middle-aged adults, although the specific behavioral risk factors may vary by age and gender.

The health burden of diabetes for the elderly in four communities

Although diabetes is a common health problem of the elderly, the impact of diabetes on health and functioning in older persons is not well established. The purpose of this analysis was to identify health conditions accompanying diabetes in four samples of community dwelling elderly people. The study samples consisted of 13,601 persons ages 65 or older who participated in the Established Populations for Epidemiologic Studies in the Elderly (EPESE). Extensive interviews were conducted in respondents' homes to obtain information on diabetes and other health conditions, health behaviors, use of health services, and demographic characteristics. A lifetime history of diabetes was reported by 14 percent of respondents. The prevalence of the disease was higher in blacks than whites, especially among women. Persons with diabetes were more likely to report myocardial infarction, stroke, vision problems, physical disability, incontinence, and nursing home stays than persons without diabetes, but the diabetics were less likely to consume alcohol or tobacco. Those with diabetes were only slightly heavier than those without diabetes at the time of the interview. However, body mass at age 50 was substantially greater among persons with diabetes. Associations between diabetes and other health conditions and behaviors were similar for whites and blacks. These results show that aged persons with diabetes experience substantial comorbidity, which has important ramifications for functioning and survival.

Factors predicting stage of breast cancer at diagnosis in middle aged and elderly women: the role of living arrangements

We examined whether sociodemographic, health, and psychosocial factors predict stage at diagnosis in 444 women aged 55-84 with newly diagnosed, microscopically confirmed breast cancer. Stage was defined as local or advanced (regional or remote). One of the most interesting predictors of disease stage was living arrangement. The odds of being diagnosed with advanced disease were twice as great among women living with a spouse than among women living alone (95% CL = 1.16, 3.35), after adjusting for the effects of age, body mass index, income, comorbid conditions, smoking, and group membership. For those living with someone other than a spouse, the odds of advanced disease were 1.7 times greater than among those living alone (95% CL = 0.96, 3.06). Middle aged and older women who live alone may be more likely to monitor their own health and to use the health care system, and therefore have a greater chance of being diagnosed at an early stage of breast cancer.

Association of education with reported age of onset and severity of Alzheimer's disease at presentation: implications for the use of clinical samples

Clinical samples are commonly used to attempt to infer factors that are etiologically important in Alzheimer's disease. Use of clinical samples for these purposes is valid if and only if detection of Alzheimer's disease is unbiased with respect to the factors being studied. The issue of how education influences detection of Alzheimer's disease is controversial. The purpose of the present investigation was to shed light on the role of education in the detection of symptoms of Alzheimer's disease. To do so, we examined the association of education with age of symptom onset, severity of disease at diagnosis, and time from symptom onset until diagnosis in a large clinical sample of Alzheimer's disease patients from throughout California. The diagnoses of the 1,658 cases in the sample were made in 1985-1990. Age of onset was defined as the age at which symptoms first appeared, according to family members. Severity of dementia was measured with Blessed-Roth Dementia Rating Scale scores. The reported age at symptom onset was later in those with less education (p < 0.0001). However, decreasing education was associated with greater severity of disease at presentation (p < 0.008), suggesting that a lower educational level may lead to later detection of Alzheimer's disease and referral to clinical centers at a later stage of disease. This implies that using clinical samples of Alzheimer's disease patients to study factors correlated with age at onset may lead to biased conclusions, if these factors are also associated with education.

Living arrangements and survival among middle-aged and older adults in the NHANES I epidemiologic follow-up study

BACKGROUND

There is concern about but little information on how living alone affects the health and survival of older adults.

METHODS

We examined the association between living arrangements (living alone, with a spouse, or with someone other than a spouse) and survival among 7651 adults, aged 45 to 74 years in the National Health and Nutrition Examination Survey (NHANES I) (1971-1975) and traced at the NHANES I Follow-up Study (1982-1984), to see whether certain sociodemographic factors (race, education, income, and employment), health behaviors (alcohol, smoking, physical activity, and obesity), or chronic medical conditions were influential in the association.

RESULTS

We found a stronger association of living arrangements with survival for men than for women, and for middle-aged men than for older men. For men, those living alone and those living with someone other than a spouse were equally disadvantaged in terms of survival. Income, race, employment, and physical activity influenced the association of living arrangements and survival, but their impact varied by age, gender, and living arrangement.

CONCLUSION

Living arrangements had a weak impact on survival among men, but had no effect among women.

The health impact of living with a cognitively impaired elderly spouse: depressive symptoms and social functioning

The purpose of this study was to identify the social and psychological consequences of living with a cognitively impaired spouse among community-dwelling elderly individuals. The study sample consisted of 318 spouse pairs drawn from a representative sample of noninstitutionalized elderly individuals. Our principal findings were that: (a) Cognitive impairment in wives is significantly (p less than .05) associated with depressive symptomatology in husbands, whereas cognitive impairment in husbands is only weakly (p greater than .20) associated with depressive symptomatology in wives; (b) Decreased participation in social/leisure activities is selectively related to spouses' level of cognitive functioning among both men and women; (c) The relationship between wives' cognitive impairment and husbands' depressive symptoms is influenced by perceived availability of financial support from friends and relatives, but not by ADL limitations in wives, lack of emotional or instrumental support from wives, household responsibilities among husbands, or lack of participation in social/leisure activities in husbands.