Amsterdam Study Of The Elderly Research Articles

Symptom Dimensions of Depression and 3-Year Incidence of Dementia: Results From the Amsterdam Study of the Elderly.

To evaluate the association between depressive symptom dimensions and incident dementia in a community sample of older persons. Depressive symptoms at baseline and incident dementia at 3-year follow-up were assessed with the Geriatric Mental State (GMS)-Automated Geriatric Examination for Computer Assisted Taxonomy in nondemented persons aged 65 years or older. Exploratory and confirmatory bifactor analysis on the depression items yielded a general depression factor characterized by all GMS items and a cognitive/motivational factor characterized by cognitive and motivational "depressive" symptoms and the absence of depressed mood. Ninety-three of 1911 persons had developed dementia at follow-up. The general depression factor increased the risk of dementia after adjustment for covariates (odds ratio [OR]: 1.48, 95% confidence interval [CI]: 1.14-1.92), but the cognitive/motivational factor did not (OR: 1.05, 95% CI: 0.75-1.47). However, in 1725 nondepressed older persons, the cognitive/motivational factor significantly predicted dementia after adjustment for covariates (OR: 1.53, 95% CI: 1.03-2.28) but not anymore after additional adjustment for subjective memory complaints (OR: 1.41, 95% CI: 0.94-2.13). The general depression factor did not significantly predict dementia in nondepressed older persons (OR: 1.15, 95% CI: 0.80-1.66). Our findings suggest that the increased risk of dementia associated with depressive symptoms in many previous studies appears to be heterogeneous, that is, it is likely due to different underlying pathways, including a pathway involving depression itself and a pathway in which cognitive and motivational symptoms reflect subjective cognitive complaints, particularly in the absence of depressed mood. These different pathways might warrant a different treatment approach.

Symptom dimensions of depression and 3-year incidence of dementia. Results from the Amsterdam Study of the Elderly (AMSTEL)

Symptom dimensions of depression and 3-year incidence of dementia. Results from the Amsterdam Study of the Elderly (AMSTEL)

Feelings of loneliness, but not social isolation, predict dementia onset: results from the Amsterdam Study of the Elderly (AMSTEL)

BackgroundKnown risk factors for Alzheimer's disease and other dementias include medical conditions, genetic vulnerability, depression, demographic factors and mild cognitive impairment. The role of feelings of loneliness and social isolation...

Reported loneliness rather than social isolation is a risk factor for 10-year mortality in older men

QUESTION Question: Do social isolation factors and feelings of loneliness predict an increased risk of mortality in older people, and does this relationship differ between men and women? Population: 4004...

Increased risk of mortality associated with social isolation in older men: only when feeling lonely? Results from the Amsterdam Study of the Elderly (AMSTEL)

Loneliness has a significant influence on both physical and mental health. Few studies have investigated the possible associations of loneliness with mortality risk, impact on men and women and whether this impact concerns the situation of being alone (social isolation), experiencing loneliness (feeling lonely) or both. The current study investigated whether social isolation and feelings of loneliness in older men and women were associated with increased mortality risk, controlling for depression and other potentially confounding factors. In our prospective cohort study of 4004 older persons aged 65-84 years with a 10-year follow-up of mortality data a Cox proportional hazard regression analysis was used to test whether social isolation factors and feelings of loneliness predicted an increased risk of mortality, controlling for psychiatric disorders and medical conditions, cognitive functioning, functional status and sociodemographic factors. At 10 years follow-up, significantly more men than women with feelings of loneliness at baseline had died. After adjustment for explanatory variables including social isolation, the mortality hazard ratio for feelings of loneliness was 1.30 [95% confidence interval (CI) 1.04-1.63] in men and 1.04 (95% CI 0.90-1.24) in women. No higher risk of mortality was found for social isolation. Feelings of loneliness rather than social isolation factors were found to be a major risk factor for increasing mortality in older men. Developing a better understanding of the nature of this association may help us to improve quality of life and longevity, especially in older men.

Clinically defined vascular depression in the general population

Vascular depression is regarded as a subtype of depression, especially in, but not entirely restricted to, the elderly, characterized by a specific clinical presentation and an association with (cerebro)vascular risk and disease. It could have major implications for treatment if subjects at risk for such a depression could be easily identified by their clinical presentation in general practice. We studied the symptom profile of depression in subjects with and without vascular risk factors in two large Dutch community-based studies, the Rotterdam Study and the Amsterdam Study of the Elderly (AMSTEL). We could not confirm the specific symptom profile in depressed subjects with vascular risk factors in either of the two cohorts. Depressed subjects with vascular risk factors showed more loss of energy and more physical disability than those without vascular risk factors. However, presumed specific symptoms of vascular depression, namely psychomotor retardation and anhedonia, were not significantly associated with any of the vascular risk indicators. Loss of energy was significantly associated with myocardial infarction and peripheral arterial disease. In these two large community-based studies we identified some differences between vascular and non-vascular depressed subjects but found no evidence for a specific symptom profile of vascular depression as previously defined.

The natural history of late-life depression: results from the Amsterdam Study of the Elderly (AMSTEL)

Background: This study examines whether risk factors related to incidence of depression are also related to prognosis, and whether a vulnerability–stress model can be established for prognosis. Methods: A prospective model for prognosis of depression (chronic or remitted course) in later life was studied in 236 depressed community-living elderly. Subjects were interviewed at baseline, and at follow-up 3 years later. Bivariate and multivariate relationships between risk factors and chronic depression (GMS-AGECAT) were assessed. Effect modification was studied between stressors and two types of vulnerability: vulnerability through a personal history of depression, and gender. Results: A personal history of depression, baseline functional limitations and incident anxiety syndrome predicted chronic depression, whereas life-events occurring between assessments, and changes in physical, functional or cognitive status did not. In subjects without a previous history, functional disabilities, male gender and receiving instrumental support correlated with a poor prognosis. The prognosis for subjects with a personal history of depression was not affected by other factors. In women, the development of chronicity was more strongly associated with a personal history than in men, whereas in men recent psychosocial and health-related characteristics were more important than in women. Limitations: Because the study consisted of two measurements with a 3-year interval, depressive episodes with a short duration may be under-represented. Conclusions: In the elderly, the impact of risk factors on the course of depression is modified by longstanding vulnerability characteristics, such as a personal history of depression and gender. More recent life stresses are related to prognosis in subjects without a personal history, and in men.

Association of depression and gender with mortality in old age. Results from the Amsterdam Study of the Elderly (AMSTEL).

The association between depression and increased mortality risk in older persons may depend on the severity of the depressive disorder and gender. To investigate the association between major and mild depressive syndromes and excess mortality in community-living elderly men and women. Depression (Geriatric Mental State AGECAT) was assessed in 4051 older persons, with a 6-year follow-up of community death registers. The mortality risk of neurotic and psychotic depression was calculated after adjustment for demographic variables, physical illness, cognitive decline and functional disabilities. A total of 75% of men and 41% of women with psychotic depression had diet at follow-up. Psychotic depression was associated with significant excess mortality in both men and women. Neurotic depression was associated with a 1.67-fold higher mortality risk in men only. In the elderly, major depressive syndromes increase the risk of death in both men and women, but mild depression increases the risk of death only in men.

Depressive symptoms and risk of Alzheimer's disease in more highly educated older people.

In an earlier study we observed that a depressive syndrome was highly predictive of developing Alzheimer's disease (AD) in older persons with normal baseline cognition and higher levels of education. We interpreted these findings as the depression being an early noncognitive manifestation of AD in persons with more cognitive reserve. The present study examines whether specific symptoms of depression can be identified that predict AD among older subjects with higher levels of education. In the community-based Amsterdam Study of the Elderly (AMSTEL), a sample of 3,147 nondemented persons with normal cognition, 65 to 84 years old, was selected and divided into subjects with >8 years and < or =8 years of education. At baseline, the presence or absence of 12 specific symptoms of depression was assessed. At follow-up, patients with incident AD were diagnosed according to DSM-IV criteria in a two-step diagnostic procedure. After an average follow-up of 3.2 years, 1,911 persons were reevaluated, of whom 22 with > 8 years and 31 with < or =8 years of education had developed AD. Multivariate logistic regression analyses showed that among persons with >8 years of education depressed mood and subjective bradyphrenia were strongly associated with incident AD. No association between depressive symptoms and AD was observed among subjects with < or =8 years of education. Both depressed mood and subjective bradyphrenia seem to indicate subclinical AD in older people with higher levels of education. Clinicians should be alert that in these persons, AD may become apparent within a relatively short period of time.

Depression and risk of cognitive decline and Alzheimer's disease. Results of two prospective community-based studies in The Netherlands.

Depression may be associated with cognitive decline in elderly people with impaired cognition. To investigate whether depressed elderly people with normal cognition are at increased risk of cognitive decline and Alzheimer's disease. Two independent samples of older people with normal cognition were selected from the community-based Amsterdam Study of the Elderly (AMSTEL) and the Longitudinal Aging Study Amsterdam (LASA). In AMSTEL, depression was assessed by means of the Geriatric Mental State Schedule. Clinical diagnoses of incident Alzheimer's disease were made using a two-step procedure. In LASA, depression was assessed with the Center for Epidemiologic Studies Depression Scale. Cognitive decline was defined as a drop of > or = 3 on the Mini-Mental State Examination at follow-up. Both in the AMSTEL and the LASA sample, depression was associated with an increased risk of Alzheimer's disease and cognitive decline, respectively, but only in subjects with higher levels of education. In a subgroup of more highly educated elderly people, depression may be an early manifestation of Alzheimer's disease before cognitive symptoms become apparent.

Cognitive reserve and mortality in dementia: the role of cognition, functional ability and depression.

This study examined whether dementia patients with greater cognitive reserve had increased mortality rates, and whether this association was different across strata of cognition, functional ability and depression. In the community-based Amsterdam Study of the Elderly, 261 non-institutionalized dementia patients, identified using the Geriatric Mental State Schedule (GMS), were followed for an average of 55.5 months after which mortality data were obtained. Cognitive reserve was indicated by years of education and pre-morbid intelligence (measured using the Dutch Adult Reading Test). Cognition, functional ability and depression were indicated by Mini-Mental State scores, ADL and IADL measurements and GMS depressive syndrome, respectively. During the follow-up 146 persons (55.9%) died. Cox regression analyses showed that more highly educated dementia patients had higher mortality rates, only if they had low MMSE scores or if they had a concurrent depression. Pre-morbid intelligence was associated with a higher mortality rate, independent of cognition, but this association was much stronger among patients with depression. The positive association between education or intelligence and mortality was not modified by functional disabilities. The results suggest that dementia patients with greater cognitive reserve have increased mortality rates, only if the disease has progressed to such an extent that clinical symptoms are more severe. In this respect, the reserve hypothesis needs a modification. Depression in dementia patients with greater cognitive reserve may reflect a subgroup of patients with poor prognosis.

Education and incident Alzheimer's disease: a biased association due to selective attrition and use of a two-step diagnostic procedure?

It is still not clear whether a low level of education increases the risk of developing Alzheimer's disease (AD). Two common problems in cohort studies involving an elderly population and a two-step diagnostic procedure are the loss to follow-up without data on the presence of AD, and the fact that, in general, people with higher levels of education perform better on traditional cognitive tests, such as the Mini-Mental State Examination (MMSE). Both phenomena may lead to misclassification, resulting in a biased association between level of education and AD. This study investigated to what extent these selection mechanisms may influence this association. In the community-based Amsterdam Study of the Elderly (AMSTEL) a cohort at risk for AD was selected of 3778 people aged 65-84 years. Level of education was expressed in two categories: low (primary education or less) versus high (partial secondary education to completed university education). At follow-up, a subsample of elderly people was selected for further diagnostic evaluation, using a memory test in addition to the MMSE. Clinical diagnoses of AD were made according to DSM-IV (Diagnostic and Statistical Manual of Mental Disorders) criteria. To examine the extent to which loss to follow-up may have affected the results, a sensitivity analysis was performed comparing two extreme possibilities. Furthermore, to examine to what extent use of the MMSE only may have affected the results, the observed odds ratio (OR) was compared with the OR based on only those AD patients who were selected for diagnostics with the MMSE alone. After an average of 3.2 years, 77 people had developed AD. Multivariate logistic regression analyses indicated that a low level of education was associated with incident AD (OR adjusted for age and sex 2.09; 95% CI: 1.29-3.38). The results of the sensitivity analysis still indicated that a low level of education was associated with incident AD. Screening with only the MMSE led to a higher OR than the one observed. Selective attrition and use of cognitive screening tests that are associated with educational level may influence the strength of the association between a low level of education and incident AD; however, it appears that these influences cannot completely explain this association.

Assessment of mental competency in community-dwelling elderly.

We studied the utility of a "vignette method" to assess mental competency for decision making on medical treatment and research participation. A vignette is a description of an imaginary situation in which the subject is asked to decide on a proposed treatment or on participation in research. His or her understanding of the situation and the quality of the reasoning underlying that choice are tested by a short series of questions. Subjects were participants in the Amsterdam Study of the Elderly (AMSTEL), a population-based study on cognitive decline and dementia. The sample consisted of elderly people (70-90 years), who were cognitively intact (n = 176) or had a dementia syndrome (n = 64; mostly Alzheimer disease). Dementia was diagnosed using the Cambridge Examination for Mental Disorders of the Elderly (CAMDEX) schedule. Two vignettes were used as competency assessment instruments. The answers to the vignette questions were summed to form a competency score. The reliability (internal consistency) of this score was 0.82 for both vignettes combined. After dichotomization into competent/incompetent (cutoff at the fifth centile of the control group), the agreement between the vignette method and a physician's judgment of competency was poor (kappa = 0.36) in the demented group. There was no agreement whatsoever when subjects with "minimal dementia" (n = 14) were left out of this analysis (kappa = 0.04). As expected, mean competency scores declined with increasing dementia severity. A multiple regression analysis showed that mental competency as measured by the vignette method was determined mainly by recent memory, expressive language, and abstract thinking. In the control group the competency score was only slightly related to education (r = 0.12) and verbal intelligence (r = 0.27). We conclude that the vignette method is a reliable and valid method for the assessment of mental competency in elderly people with cognitive decline. The vignette method is preferred over a physician's judgment, especially in patients with early dementia.

Apolipoprotein E phenotype is not related to late-life depression in a population-based sample.

Apolipoprotein E (ApoE) allele frequencies were examined in a population-based sample (n = 475: age range 65-84 years: Amsterdam Study of the Elderly). The relation of ApoE epsilon 4 with dementia and with various types of late-life depression was studied. Depression was measured with the Geriatric Mental State schedule. Dementia was diagnosed by DSM-III-R criteria. It was expected that ApoE epsilon 4 allele frequencies would be elevated not only in Alzheimer's disease and dementia in general, but also in first episode, late-life depression accompanied by subtle cognitive impairment (possibly organic depression). However, the results indicated that epsilon 4 allele frequency is related to (family history of) dementia and cognitive impairment, but not to possibly organic depression. The main predictor of late-life depression is an episode of psychiatric problems before the age of 65 years.

The effects of intelligence and education on the development of dementia. A test of the brain reserve hypothesis

A number of recent epidemiological studies have shown that the prevalence and incidence of dementia are increased in population strata with low compared to high levels of education. This has been explained as a consequence of a greater 'brain reserve capacity' in people with a high level of education. Theoretically, however, brain reserve capacity is better reflected by intelligence than by level of education. Thus, the emergence of dementia will be better predicted by low pre-morbid intelligence than by low education. This prediction was tested in a population based sample of elderly subjects (N = 2063; age range 65-84; Amsterdam Study of the Elderly) who were followed over 4 years. Dementia was diagnosed using the Geriatric Mental State examination (GMS). Pre-morbid intelligence was measured using the Dutch Adult Reading Test (DART), a short reading test which gives a good estimate of verbal intelligence, and is relatively insensitive to brain dysfunction. The effects of age, gender, occupational level, number of diseases affecting the central nervous system and family history of dementia or extreme forgetfulness were also examined. Logistic regression analysis showed that low DART-IQ predicted incident dementia better than low level of education. A high occupational level (having been in charge of subordinates) had a protective effect. This result supports the brain reserve theory. It also indicates that low pre-morbid intelligence is an important risk factor for cognitive decline and dementia. Use of reading ability tests is to be preferred over years of education as estimator of pre-morbid cognitive level in (epidemiological) dementia research.

Subjective memory complaints in the elderly: depressive symptoms and future dementia.

Population studies indicate that subjective memory complaints by elderly people are correlated with cognitive performance. These complaints have some predictive power regarding the development of dementia. The present study attempted to replicate this finding, and investigated which variables determine subjective memory complaints. Participants in the Amsterdam Study of the Elderly (n = 2114; 65-84 years of age), who were not demented and had a normal MMSE score (> 23) at baseline, were re-examined after four years. Subjective complaints were measured using a previously developed scale. Dementia and depression were measured using the Geriatric Mental State Schedule (GMS). Premorbid intelligence was measured by the Dutch Adult Reading Test (DART). Memory complaints at baseline contributed a small but significant amount of diagnostic information with respect to the prediction of future dementia. Depressive symptoms at baseline had no predictive value when these memory complaints were accounted for. Subjective memory complaints were associated with depression, baseline MMSE score, and premorbid intelligence. Subjective memory complaints are not just secondary to depression, but in part reflect realistic self-observations of cognitive decline.

Low education is a genuine risk factor for accelerated memory decline and dementia

A relatively high prevalence and incidence of dementia have been found in population strata with low levels of education in comparison to population strata with high levels of education. However, doubt remains whether this may be an artifact of education bias in the screening tests used. To investigate this matter, we analyzed results of two Dutch population surveys in which unbiased measures of memory decline were used. In the Longitudinal Aging Study Amsterdam ( n = 1774) the percentage of words retained in a verbal learning test was found to be disproportionately low in the oldest age cohort (80–85 years) with less than 11 years of education. The Amsterdam Study of the Elderly ( n = 4051) found a “dose-response” relationship between education and dementia prevalence. Cross-sectional and longitudinal results showed that, in less educated people, memory decline is faster and sets in at an earlier age. These findings indicate that the relationship between dementia and education is not just an artifact of case detection methods.

Increased risk of mortality in Alzheimer's disease patients with higher education? A replication study.

The objective of this study was to replicate findings from an earlier study by Stern et al. of an increased risk of mortality in Alzheimer's disease (AD) patients with higher levels of education and to compare this risk with the risk of death in the elderly population. As part of a community-based follow-up study on dementia (Amsterdam Study of the Elderly [AMSTEL]) a cohort of 4,051 noninstitutionalized elderly age 65 to 84 years stratified in four 5-year strata of equal size was screened for dementia using the MMSE (Mini-Mental State Examination). Those suspected of dementia received diagnostic evaluation using the CAMDEX (Cambridge examination for mental disorders in the elderly). Clinical diagnoses of probable AD were made according to NINCDS-ADRDA criteria. Thirty-six prevalent patients were diagnosed as having AD. The suspected subcohort was followed up yearly over a period of 4 years. During the three yearly follow-ups, 30 incident patients received a diagnosis as well. After 6 years mortality data were obtained from municipality records. Cox proportional hazards models adjusted for age and sex were used to estimate the relative risk of death associated with the level of education. Relative risk of death decreased (although not statistically significant) in AD patients as level of education increased (RR = 0.86; 95% CI, 0.63 to 1.19). In the full baseline sample, relative risk of death decreased as level of education increased (RR = 0.93; 95% CI, 0.89 to 0.97). In this study we could not replicate the findings of Stern et al. of an increased risk of death in more highly educated AD patients. Several major differences between the two studies, among which difference in populations used is considered to be most important, are discussed that might explain the conflicting results. We conclude that higher education is not associated with increased risk of mortality in AD patients.

Subjective memory complaints may announce dementia.

Whether subjective memory complaints in the absence of objective memory decline can predict future dementia has been investigated only in highly selected clinical and volunteer cohorts. Our study examines this question in a subsample of AMSTEL (Amsterdam Study of the Elderly), a longitudinal population study on cognitive decline and dementia. Subjects (aged 65 to 84 years; n = 357) without dementia or other psychiatric disorders at baseline were followed for 3 years. After this interval, 16 of 203 re-examined patients developed a dementia. Logistic regression analyses indicated that memory complaints at baseline contributed a small but significant amount of diagnostic information. However, the most powerful predictor of future dementia was deficient memory performance. We conclude that subjective memory complaints may predict dementia within 3 years, particularly when there are objective signs of memory deterioration.

Nonresponse Pattern and Bias in a Community-based Cross-sectional Study of Cognitive Functioning among the Elderly

The demographic, health, and mental functioning characteristics of nonresponders to a community-based cross-sectional study of cognitive functioning among the elderly in Amsterdam, the Netherlands (Amsterdam Study of the Elderly (AMSTEL), October 1990 to May 1991), were examined and compared with responders. The randomly selected age-stratified (65-74, 75-84 years) sample was drawn from nonresponders listed with a subsample (n = 8) of general practitioners whose lists served as the sampling frame for the main study. The general practitioners approached and interviewed the responding nonresponders using the same standardized questions that were used in the main study. Nonresponders (n = 115) and responders (n = 999) from the same medical practices were compared by means of chi-square and odds ratios. Compared with responders, these nonresponders more often reported a history of psychiatric illness, heart attack, stroke, and diabetes, and were more likely to be unmarried, to have a lower education, and to do poorly on the cognitive test (odds ratio = 1.6, 95% confidence interval 1.0-2.6). Most significant physical and mental health differences by response status were seen among the persons aged < 75 years and not among those aged > or = 75 years. The odds for poor cognitive test performance associated with age and stroke were relatively more biased than those associated with other risk factors. These results suggest that the characteristics of young-old and old-old elderly nonresponders to cross-sectional studies of cognitive function may differ, and that there may be selective nonresponse that could bias, to a different degree, estimates of risk for poor cognitive functioning. Studies should investigate the possibilities for nonresponse in their own setting.