Health and functioning among the elderly of Marin County, California: a glimpse of the future

Volunteerism and Mortality among the Community-dwelling Elderly

Older residents (N 5 1972) in California were investigated prospectively for association of volunteering service to others and all-cause mortality. Potential confounding factors were studied: demographics, health status, physical functioning, health habits, social support, religious involvement, and emotional states. Possible interaction effects of volunteering with religious involvement and social support were also explored. Results showed that 31 percent (n 5 630) of respondents volunteered, about half (n5289) for more than one organization. High volunteers ([.greaterequal]2 organizations) had 63 percent lower mortality than nonvolunteers (age and sex-adjusted) with relative hazard (RH) 5 0.37, confidence interval (CI) 5 0.24, 0.58. Multivariate adjustment moderately reduced difference to 44 percent (RH 5 0.56, CI 5 0.35, 0.89), mostly due to physical functioning, health habits, and social support. Unexpectedly, volunteering was slightly more protective for those with high religious involvement and perceived social support. After multivariate adjustment, any level of volunteering reduced mortality by 60 percent among weekly attenders at religious services (RH 5 0.40; CI 5 0.21,0.74). Lower mortality rates for community service volunteers were only partly explained by health habits, physical functioning, religious attendance, and social support.

Non-standard vision measures predict mortality in elders: the Smith-Kettlewell Institute (SKI) study

PURPOSE

To determine which vision tests predict mortality within 10 years in a community-based elderly sample.

METHODS

Nine hundred residents of Marin County, California 58 to 101 years of age (mean 75 years at baseline), underwent a battery of tests, including high contrast acuity, low contrast acuity, low contrast/low luminance acuity, acuity in glare, contrast sensitivity, color vision, stereopsis, standard and attentional fields. The association between the vision tests and mortality within 10 years of baseline was assessed with Cox Proportional Hazards models controlling for age, sex, education level, depression, cognitive status and self-reported medical conditions.

RESULTS

Forty-three percent of the sample died within 10 years of baseline. When controlling for mortality-related covariates, impairment in any of the vision measures was associated with increased risk of death. However, non-standard vision measures (ie, impairment in low contrast/low luminance acuity, standard field integrity and the impact of the attentional task on field integrity) were more highly associated with mortality than standard high contrast acuity.

CONCLUSIONS

In agreement with other studies, we find that visual impairment is a significant predictor of death. However, the strongest relationship was found for measures other than high contrast acuity. These results suggest that non-standard vision measures may be more sensitive indicators of generalized aging in the most elderly.

Population-based cohorts of the 50s and over: a summary of worldwide previous and ongoing studies for research on health in ageing

As most countries face the ageing of their population, understanding successful and pathologic ageing is a research priority. Longitudinal studies examining the ageing process from middle-age are required to establish causal and valid relationships. This systematic review of the literature aimed at identifying large community-based longitudinal studies either including exclusively elderly people or following people from middle-age (50+ years at enrolment) to death, and resulted in a selection of 72 cohort studies. Design features of selected studies show that most were conducted in North America or Northern Europe, most included both genders, and follow-up period was often less than 10 years. Many cohorts focused on cardiovascular health, cognitive decline or osteoporosis. Usually collected variables comprise of self-reported data on socio-demographics, chronic diseases and functional status, as well as measures of cognition, anthropometrics and physical performances. Biological samples were taken in about 60% of the studies, and a third also undertook genetic analyses. This review summarises information on design and content of large population-based cohorts of older persons, and represents a valuable background from which additional data may be retrieved.

Face Recognition in the Elderly

PURPOSE

The purpose of this study was to assess face recognition ability in a large sample of elders (n=572, mean age=78.1 years) and to identify factors that affect performance.

METHODS

Face recognition was measured by presenting standardized faces of varying sizes to simulate normal-sized faces at different viewing distances. Subjects were asked to identify the name of the person and their facial expression. Threshold equivalent viewing distance (EVD) was calculated. High- and low-contrast acuity, contrast sensitivity, low-contrast/low-luminance acuity, disability glare, stereoacuity, and visual field measures (with and without an attentional task) were also measured. These vision measures, along with demographic information (age, sex, education) and cognitive status, were included in a multiple regression analysis to determine which factors predicted task performance.

RESULTS

This cross-sectional sample of elders showed significant declines in face recognition with age. Mean threshold EVD ranged from 8.0 m for participants<or=70 years of age to 2.2 meters for those over 85 years. Multiple regression analysis revealed that age, sex, years of education, spatial vision, and cognitive status were all significant predictors of face recognition, accounting for approximately 46% of the variability. Spatial vision (high-contrast acuity) and age were the best predictors. Although each spatial vision measure was significantly correlated with face recognition, adding low-contrast or contrast sensitivity measures to the regression analysis explained no more variance than age and high-contrast acuity alone.

CONCLUSIONS

The marked decline in face recognition ability in elders is related to declines in spatial vision and cognitive status. All spatial vision measures have similar predictive ability for face recognition.

Night Driving Self-Restriction: Vision Function and Gender Differences

PURPOSE

The purpose of this study was to evaluate gender differences in the relationship between night driving self-restriction and vision function in an older population.

METHODS

Night driving self-restriction patterns (assessed by questionnaire) were examined cross-sectionally in relation to age, gender, health and cognitive status, depression, and vision function in a sample of 900 elders (mean age, 76 years) living in Marin County, California.

RESULTS

Of the total sample, 91% of men and 77% of women were current drivers. The mean age of the drivers was 73.3 years (range, 58-96 years). Among current drivers, women had slightly better vision function than men on most measures (low-contrast acuity, contrast sensitivity, low-contrast acuity in glare, low-contrast, low-luminance acuity, and glare recovery) but were twice as likely as men to restrict their driving to daytime. Men showed significant associations with avoidance of night driving on four spatial vision measures (high- and low-contrast acuity, low-contrast, low-luminance acuity, and contrast sensitivity). For women, in addition to these measures, a significant association was seen for low-contrast acuity in glare. Neither men nor women showed significant associations between driving restriction and performance on the other vision measures examined (glare recovery time, attentional field integrity, or stereopsis). The vision measures most predictive of self-restriction were contrast sensitivity for men and low-contrast acuity in glare for women.

CONCLUSIONS

Including both cessation and self-restriction, men over age 85 years are 6.6 times more likely than women to be driving at night. For both genders, vision plays a significant role in the self-restriction decision. A higher percentage of men than women continue to drive at night with poor vision. Men's night-driving cessation was associated with contrast sensitivity and depression, whereas women's night-driving cessation was associated with low-contrast acuity in glare as well as age.

Factors associated with uncontrolled hypertension in an affluent, elderly population

OBJECTIVE

To explore demographic, economic, and treatment-related associations with uncontrolled hypertension in a relatively affluent, community-dwelling population.

METHODS

Two home surveys of 655 and 432 subjects with a diagnosis of hypertension were completed in 1995 and 1999, respectively. Trained surveyors recorded medication history plus demographic and socioeconomic variables, as well as several measurements of blood pressure in the home. Uncontrolled hypertension was defined according to guidelines set forth by the Sixth Report of the Joint National Committee on prevention, detection, evaluation, and treatment of high blood pressure. Odds ratios for observing an elevated blood pressure given the patients' medication history, income, insurance coverage, demographic variables, and concomitant disease were estimated using multivariable logistic regression.

RESULTS

On both occasions, >60% of the study population had an average blood pressure that was above recommended levels. Diuretic therapy alone (1995 survey) or in combination with an angiotensin-converting enzyme inhibitor (1999 survey) decreased the odds ratio for uncontrolled hypertension by 39% (p = 0.027) and 62% (p = 0.005), respectively. Lack of prescription drug insurance and a history of arthritis had negative effects, increasing the odds ratio for uncontrolled hypertension by more than twofold (p < 0.05).

CONCLUSIONS

Uncontrolled hypertension occurs commonly among elderly patients notwithstanding a relatively high standard of living. The choice of medication, presence of concomitant disease, and availability of insurance may be important factors influencing blood pressure control.

Chronic disease, functional status, and self-ascribed causes of disabilities among noninstitutionalized older people in Spain

BACKGROUND

A major component of disability is related to chronic disease, but the study of self-reported causes of disability could add new aspects in understanding this process. The main objective of this work was to determine the associations between chronic diseases and disability and to describe the pattern of self-reported causes of the disabilities present in older persons.

METHODS

We carried out a survey in a probabilistic sample of people aged 65 and older of the city of Madrid. The initial sample size was 1001. Subjects were interviewed in their homes. We asked about the presence of 14 chronic conditions. Self-reported difficulty and dependence in 9 noninstrumental activities of daily living (ADLs) were ascertained. Subjects were asked to report the main cause responsible for the disability. Multivariate logistic regression models were constructed to estimate the association of each chronic condition with the probability of having disability.

RESULTS

Final sample size was 772 people (overall response rate 77.0%). Interviews answered by proxies were 7.5%. Only 4.5% declared no chronic condition. Osteoarthitis/rheumatism was the most prevalent condition (56.8%). In addition, 63.2% were independent, 21.3% were independent with difficulty (in at least one ADL), and 15.5% were dependent (in at least one ADL). Subjects attributed to osteoarthitis and to aging 41.8% and 17.1% of all disabilities, respectively. Chronic conditions strongly associated with disability were cerebrovascular disease (adjusted odds ratio [OR]: 3.51 [95% confidence interval: 1.44-8.60]), depression/anxiety disorders (OR: 2.72 [1.83-4.05]), and diabetes (OR: 2.18 [1.24-3.83]).

CONCLUSIONS

Cerebrovascular diseases, depression/anxiety disorders, and diabetes were the conditions more clearly related to disability. On the other hand, a large proportion of subjects attribute their disabilities to osteoarthritis and old age.

Development of refractive errors into old age

PURPOSE

To evaluate refractive errors in older adults.

METHODS

The distribution of refractive error components was evaluated in a sample of 569 older adults including 171 participants over the age of 80 years. The mean age was 75.2 years with a range from 59 to 106 years. Emphasis was placed on modern methods of analyzing astigmatic refractive errors, which convert cylindrical refractive errors into primary and oblique components.

RESULTS

The known increase in hyperopia after maturity continues into old age. The primary negative astigmatic component increases dramatically in prevalence and amount after age 70 years, whereas the oblique component remains unchanged. Significant anisometropia is common in the oldest old, suggesting failure of emmetropization mechanisms with age. Substantial gender differences exist in refractive changes with age.

CONCLUSIONS

The continuing changes in all components of refractive error into old age and the surprisingly high prevalence of large amounts of astigmatism and anisometropia emphasize the importance of regular refractive evaluations among the oldest old.

Is vision function related to physical functional ability in older adults?

OBJECTIVES

To assess the relationship between a broad range of vision functions and measures of physical performance in older adults.

DESIGN

Cross-sectional study.

SETTING

Population-based cohort of community-dwelling older adults, subset of an on-going longitudinal study.

PARTICIPANTS

Seven hundred eighty-two adults aged 55 and older (65% of living eligible subjects) had subjective health measures and objective physical performance evaluated in 1989/91 and again in 1993/95 and a battery of vision functions tested in 1993/95.

MEASUREMENTS

Comprehensive battery of vision tests (visual acuity, contrast sensitivity, effects of illumination level, contrast and glare on acuity, visual fields with and without attentional load, color vision, temporal sensitivity, and the impact of dimming light on walking ability) and physical function measures (self-reported mobility limitations and observed measures of walking, rising from a chair and tandem balance).

RESULTS

The failure rate for all vision functions and physical performance measures increased exponentially with age. Standard high-contrast visual acuity and standard visual fields showed the lowest failure rates. Nonstandard vision tests showed much higher failure rates. Poor performance on many individual vision functions was significantly associated with particular individual measures of physical performance. Using constructed combination vision variables, significant associations were found between spatial vision, field integrity, binocularity and/or adaptation, and each of the functional outcomes.

CONCLUSIONS

Vision functions other than standard visual acuity may affect day-to-day functioning of older adults. Additional studies of these other aspects of vision and how they can be treated or rehabilitated are needed to determine whether these aspects play a role in strategies for reducing disability in older adults.

The Smith-Kettlewell Institute (SKI) longitudinal study of vision function and its impact among the elderly: an overview

We present an overview of a multifaceted longitudinal study of vision function and its interaction with daily activities, health, and well-being among 900 persons aged 58 to 102 years at the first visit. Standard vision measures as well as nonconventional tests designed to assess visual performance under the nonideal conditions encountered in everyday life were used. Here we summarize a few of the findings to date, with an emphasis on a direct comparison of declines in different aspects of vision function with age. The rates of declines with advancing age vary widely for the different vision functions. Also described is the reading performance of the sample and its association with some of the vision measures. Furthermore, we describe some of the associations between vision test scores and extensive longitudinal health and functioning data collected by the Buck Center for Research in Aging. Findings show that many older people with good acuity are effectively visually impaired in performing everyday tasks involving low and changing light levels, stereopsis, glare, and low contrast. We also found that vision under nonideal conditions cannot be predicted from standard acuity on an individual basis.

Reading performance in older adults with good acuity

PURPOSE

This study evaluated factors affecting reading performance in a sample (N = 544) of older adults (mean age 72.8 years, range 58 to 102) with good high-contrast acuity (> or = 20/32).

METHODS

Using the Pepper Reading Test, the relationship between reading rate and several vision measures was assessed.

RESULTS

Mean corrected reading rate fell substantially over the age range tested despite the fact that these individuals all had good acuity. However, multiple regression analysis indicated that when other measures were taken into account (most notably, low-contrast vision, motor ability, and attentional field integrity), age was not a significant independent predictor of corrected reading rate.

CONCLUSION

Reading is an important skill, and ways of enhancing reading performance should be explored. Good high-contrast acuity does not assure that older individuals can read satisfactorily.

Age-associated diseases and conditions: implications for decreasing late life morbidity

We discuss two types of age-associated diseases; aging-dependent such as Alzheimer's disease and congestive heart failure which increase logarithmically with age, versus age-dependent such as multiple sclerosis and amyotrophic lateral sclerosis which occur at proscribed ages, and then occurrence of new cases ceases or diminishes with further aging. Prevention strategies with both types emphasize postponement or delay of onset. The non-fatal aging-dependent diseases and conditions are an accumulating burden as we age, and increase overall morbidity in late years. These include Alzheimer's disease and other dementias, Parkinson's disease, loss of vision and hearing, incontinence, osteoporosis and hip fracture, osteoarthritis and depression. With mortality postponed, we will be living for many years at old and vulnerable ages. Life's quality will be reasonable for most. Still, increasing the chance that all will experience this desirable outcome requires pursuing the means to delay the onset of the physical and social events which we categorize as the non-fatal aging-dependent diseases and conditions. We must recognize that each added year occurs at the tip of an exponential curve where risk is maximal.

Religion and mortality among the community-dwelling elderly

OBJECTIVES

This study analyzed the prospective association between attending religious services and all-cause mortality to determine whether the association is explainable by 6 confounding factors: demographics, health status, physical functioning, health habits, social functioning and support, and psychological state.

METHODS

The association between self-reported religious attendance and subsequent mortality over 5 years for 1931 older residents of Marin County, California, was examined by proportional hazards regression. Interaction terms of religion with social support were used to explore whether other forms of social support could substitute for religion and diminish its protective effect.

RESULTS

Persons who attended religious services had lower mortality than those who did not (age- and sex-adjusted relative hazard [RH] = 0.64; 95% confidence interval [CI] = 0.52, 0.78). Multivariate adjustment reduced this relationship only slightly (RH = 0.76; 95% CI = 0.62, 0.94), primarily by including physical functioning and social support. Contrary to hypothesis, religious attendance tended to be slightly more protective for those with high social support.

CONCLUSIONS

Lower mortality rates for those who attend religious services are only partly explained by the 6 possible confounders listed above. Psychodynamic and other explanations need further investigation.

Can money buy happiness? Depressive symptoms in an affluent older population

OBJECTIVES

To determine if the inverse association between depressive symptoms and income reported in predominantly low- and middle-income older populations is present in a more affluent population of older adults and to determine if this pattern is independent of other known correlates of depressive symptoms such as medical problems, physical disability, and social support.

DESIGN

Cross-sectional analysis within a prospective cohort study.

SETTING

An ongoing, community-based cohort study conducted by an independent research institution in an affluent Northern California county.

PARTICIPANTS

A total of 1948 randomly selected, noninstitutionalized county residents 55 years of age and older who completed the baseline questionnaire and physical performance tests.

MEASUREMENTS

The outcome measure was high level of depressive symptoms (score > or = 16) using the Center for Epidemiologic Studies-Depression scale (CES-D).

RESULTS

The prevalence of high levels of depressive symptoms (CES-D score > or = 16) was lower than in most other population-based samples using an identical CES-D scale. In age-adjusted, sex-specific analyses, increasing income level was associated significantly with lower levels of depressive symptoms, but the nature of the relationship appeared quadratic rather than linear (Men: odds ratio (OR) income .80, 95% confidence interval (CI) .68-.94; income2 OR 1.006, 95% CI 1.001-1.011. Women: OR income .80, 95% CI .69-.91; income2 OR 1.007, 95% CI 1.002-1.011). In multivariate regression analyses including potential confounding risk factors, the magnitude of the association between depressive symptoms and income decreased and was not statistically significant when measures of health conditions, physical disability, and social support were included in the model (Men: OR income .90, 95% CI .75-1.06; income2 OR 1.003, 95% CI .998-1.009. Women: OR income .90, 95% CI .78-1.05; income2 OR 1.003, 95% CI .998-1.008).

CONCLUSION

These findings suggest that poor health, physical disability, and social isolation are the major factors responsible for the observed inverse relationship between income and symptoms of depression in affluent, as well as economically disadvantaged, older populations.