Classification models for identification of at-risk groups for incident memory complaints.

BACKGROUND: Memory complaints in older adults may be a precursor of measurable cognitive decline. Causes for these complaints may vary across age groups. The goal of this study was to develop classification models for the early identification of persons at risk for memory complaints using a broad range of characteristics. METHODS: Two age groups were studied, 55-65 years old (N = 1,416.8) and 65-75 years old (N = 471) using data from the Longitudinal Aging Study Amsterdam. Participants reporting memory complaints at baseline were excluded. Data on predictors of memory complaints were collected at baseline and analyzed using logistic regression analyses. Multiple imputation was applied to handle the missing data; missing data due to mortality were not imputed. RESULTS: In persons aged 55-65 years, 14.4% reported memory complaints after three years of follow-up. Persons using medication, who were former smokers and had insufficient/poor hearing, were at the highest risk of developing memory complaints, i.e., a predictive value of 33.3%. In persons 65-75 years old, the incidence of memory complaints was 22.5%. Persons with a low sense of mastery, who reported having pain, were at the highest risk of memory complaints resulting in a final predictive value of 56.9%. In the subsample of persons without a low sense of mastery who (almost) never visited organizations and had a low level of memory performance, 46.8% reported memory complaints at follow-up. CONCLUSIONS: The classification models led to the identification of specific target groups at risk for memory complaints. Suggestions for person-tailored interventions may be based on these risk profiles.

Depression and cognition: how do they interrelate in old age?

OBJECTIVES: To disentangle the reciprocal effects between depressive symptoms and cognitive functioning over time and to study the association between changes in their trajectories using 13 years of follow-up. DESIGN AND PARTICIPANTS: Data were used from five waves of the population-based Longitudinal Aging Study Amsterdam. Subjects were included if data was present on depressive symptoms and cognitive performance on at least two occasions, which resulted in a study sample of N = 2,299. MEASUREMENTS: Depressive symptoms were assessed with the Center for Epidemiologic Studies Depression Scale. Cognitive functioning was assessed using the Mini-Mental State Examination (general cognitive functioning) and timed coding task (speed of information processing). RESULTS: Cross-domain latent change analyses showed that depression at baseline predicted both decline of general cognitive functioning and information processing speed, independent of relevant covariates. Conversely, information processing speed at baseline, but not general cognitive functioning was related to the course of depressive symptoms. The course of cognitive functioning was not significantly associated with the course of depressive symptoms. CONCLUSION: Depressive symptoms in older patients flag an increased likelihood of cognitive decline. This effect is considerable and may be due to several underlying mechanisms. The likelihood of the relationship reflecting either a causal effect of depression on cognitive decline, or a common cause, or both, should be estimated. Likewise, older persons with more limitations in information processing speed specifically are more vulnerable to increases in depression.

Do employed and not employed 55 to 64-year-olds' memory complaints relate to memory performance? A longitudinal cohort study.

BACKGROUND: Whether middle-aged individuals are capable of employment continuation may be limited by poor memory. Subjective memory complaints may be used to identify those at risk of poor memory. Research questions, therefore, were (i) are prevalent memory complaints associated with relevantly poor memory performance and decline in 55 to 64-year-olds; (ii) are incident memory complaints associated with relevant memory decline; and (iii) do these associations differ between employed and not employed individuals? METHODS: Participants of the Longitudinal Aging Study Amsterdam (LASA) were examined. Data were weighted by sex, age and region. To examine the association of prevalent memory complaints with relevantly poor learning ability (n=903) and delayed recall (n=897; both assessed with the Auditory Verbal Learning Test), subnormal (≤ mean-1 SD) and impaired (≤ mean-1.5 SD) memory performance were defined. To examine the association of prevalent and incident memory complaints with relevant decline after 3 years in learning ability (n=774 and 611, respectively) and delayed recall (n=768 and 603, respectively), above normal (≤ mean-1 SD) and clinically relevant (≤ mean-1.5 SD) memory decline were investigated. Logistic regression analyses were applied. RESULTS: Adjusted for gender, education and age, individuals with memory complaints more often had impaired delayed recall and clinically relevant decline in learning ability. Incident memory complaints were borderline significantly associated with clinically relevant decline in learning in continuously employed individuals (paid job ≥ 1 h weekly), but not in continuously not employed individuals. CONCLUSION: Memory complaints may identify 55 to 64-year-olds at risk of memory impairment and decline. Our results provide hypotheses about the association between memory complaints and decline in employed 55 to 64-year-olds.

Classification models for early identification of persons at risk for dementia in primary care: an evaluation in a sample aged 80 years and older.

AIM: To evaluate previously developed classification models to make implementation in primary care possible and aid early identification of persons at risk for dementia. METHODS: Data were drawn from the OCTO-Twin study. At baseline, 521 persons >or= 80 years of age were nondemented, and for 387 a blood sample was available. Predictors of dementia were collected and analyzed in initially nondemented persons using generalized estimating equations and Cox survival analyses. RESULTS: In the basic model using predictors already known or easily obtained (basic set), the mean 2-year predictive value increased from 6.9 to 28.8% in persons with memory complaints and an MMSE score

Time Trend in Persistent Cognitive Decline: Results From the Longitudinal Aging Study Amsterdam.

Objective: To study time trends in the incidence of persistent cognitive decline (PCD), and whether an increase or decrease is explained by changes in well-known risk factors of dementia. Method: Data from the Longitudinal Aging Study Amsterdam over a period of 20 years were used. Subsamples of 65-88 year-olds were selected at 7 waves, with numbers ranging from 1,800 to 1,165. Within-person change in cognitive functioning was used to determine PCD. In logistic generalized estimating equations (GEE), time (0, 3, 6, 9, 13, and 16 years) was the main predictor of 3-year PCD incidence. Explanatory variables were lagged one wave before incident PCD and included in separate models. Results: PCD incidence was 2.5% at first, and 3.4% at last follow-up. GEE showed a positive time trend for PCD incidence [Exp(B)time = 1.042; p < .001]. None of the explanatory variables significantly changed the strength of the regression coefficient of linear time. Higher age, lower education, diabetes mellitus, smoking, lower body-mass index, and lower level of physical activity were associated with higher incidence of PCD. Conclusion: An increase in PCD incidence over time was found. Although well-known risk factors were associated with incidence per se, they did not explain the increase in incidence of PCD.

Within-Person Pain Variability and Mental Health in Older Adults With Osteoarthritis: An Analysis Across 6 European Cohorts.

Pain is a key symptom of osteoarthritis (OA) and has been linked to poor mental health. Pain fluctuates over time within individuals, but a paucity of studies have considered day-to-day fluctuations of joint pain in relation to affective symptoms in older persons with OA. This study investigated the relationship of pain severity as well as within-person pain variability with anxiety and depression symptoms in 832 older adults with OA who participated in the European Project on OSteoArthritis (EPOSA): a 6-country cohort study. Affective symptoms were examined with the Hospital Anxiety and Depression Scale, pain severity was assessed with the Western Ontario and McMaster Universities OA Index and the Australian/Canadian Hand Osteoarthritis Index, and intraindividual pain variability was measured using pain calendars assessed at baseline, 6, and 12 to 18 months. Age-stratified multiple linear regression analyses adjusted for relevant confounders showed that more pain was associated with more affective symptoms in older-old participants (74.1-85 years). Moreover, older-old participants experienced fewer symptoms of anxiety (ratio = .85, 95% confidence interval [CI], .77-.94), depression (ratio = .90, 95% CI, .82-.98), and total affective symptoms (ratio = .87, 95% CI, .79-.94) if their pain fluctuated more. No such association was evident in younger-old participants (65-74.0 years). These findings imply that stable pain levels are more detrimental to mental health than fluctuating pain levels in older persons. PERSPECTIVE: This study showed that more severe and stable joint pain levels were associated with anxiety and depressive symptoms in older persons with OA. These findings emphasize the importance of measuring pain in OA at multiple time points, because joint pain fluctuations may be an indicator for the presence of affective symptoms.

Prevalence and incidence of memory complaints in employed compared to non-employed aged 55-64 years and the role of employment characteristics.

OBJECTIVES: To examine the association of employment status and characteristics with prevalent and incident memory complaints (MC) in 55-64-year-olds. METHODS: Subjects were participants of the Longitudinal Aging Study Amsterdam (LASA). Respondents with baseline data were selected to examine the association of employment status (n = 1525) and employment characteristics (n = 1071) with prevalent MC (i.e., MC at baseline). Respondents without MC at baseline were selected to examine the association of employment (n = 526) and employment characteristics (n = 379; working hours, job prestige, job level, psychological job demands, iso-strain) with incident MC (i.e., no MC at baseline and MC at three-year follow-up). Associations were adjusted for relevant covariates (demographics, memory performance, physical health, mental health, personality traits). Logistic regression was applied. Data were weighed according to gender and age of the Dutch population. RESULTS: At baseline 20.5% reported MC. At three-year follow-up, 15.4% had incident MC. No associations were found between employment status and MC. Adjusted analysis revealed that individuals with high occupational cognitive demands were more likely to have prevalent MC. CONCLUSIONS: Middle-aged workers are equally as likely to experience MC as non-working age-peers. Among workers, those with cognitively demanding work were more likely to experience MC, independent of memory performance. Memory decline due to ageing may be noticed sooner in 55-64-year-olds performing cognitively demanding work.

The role of extracerebral cholesterol homeostasis and ApoE e4 in cognitive decline.

We examined the associations between extracerebral markers of cholesterol homeostasis and cognitive decline over 6 years of follow-up, and studied the modifying effect of apolipoprotein E (ApoE) e4. Data were collected in the Longitudinal Aging Study Amsterdam (n = 967, with longitudinal data on cognition, ages ≥ 65 years) and analyzed using linear mixed models. General cognition (Mini-Mental State Examination; MMSE), memory (Auditory Verbal Learning Test), and information processing speed (Coding task) were measured. The results show that ApoE e4 was a significant effect modifier. Significant associations were found only in ApoE e4 noncarriers (n = 718). We found a nonlinear negative association between the ratio of lanosterol to cholesterol (≤ 189.96 ng/mg), a marker for cholesterol synthesis, and general cognition. Lower cholesterol absorption, i.e., lower ratios of campesterol and sitosterol to cholesterol, as well as a higher rate of cholesterol synthesis relative to absorption were associated with lower information processing speed. In ApoE e4 carriers, the negative association between the ratio of campesterol to cholesterol and memory reached borderline significance. Future research should focus on the interaction between (disturbed) cholesterol homeostasis and ApoE e4 status with respect to dementia.

Role of lipoproteins and inflammation in cognitive decline: do they interact?

The aim of this study was to examine the associations between high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol, triglycerides, and cognition and focus on the modifying effect of inflammation. Data were collected in the population-based Longitudinal Aging Study Amsterdam and analyzed with mixed linear models. The sample comprised 1003 persons ≥ 65 years with cognitive data on at least 2 occasions over 6 years of follow-up. Cognition was measured with the Mini-Mental State Examination (general cognition), Auditory Verbal Learning Test (memory), and Coding Task (information processing speed). We found an independent association between high HDL cholesterol and better memory performance. In addition, low LDL cholesterol was predictive of worse general cognitive performance and faster decline on information processing speed. Furthermore, a significant modifying effect of inflammation (C-reactive protein, α-antichymotrypsin) was found. A negative additive effect of low LDL cholesterol and high inflammation was found on general cognition and memory performance. Also, high triglycerides were associated with lower memory performance in those with high inflammation. Thus, a combination of these factors may be used as markers of prolonged lower cognitive functioning.

Accumulated and differential effects of life events on cognitive decline in older persons: depending on depression, baseline cognition, or ApoE epsilon4 status?

OBJECTIVES: The study examined the accumulated as well as the differential influence of negative life events on cognitive decline in older persons, and whether this association was different for persons with normal and poor cognitive functioning, and for ApoE ε4 carriers and noncarriers. METHODS: We used data from the Longitudinal Aging Study Amsterdam (N = 1,356). Data were analyzed using linear mixed models. RESULTS: We found differential associations for different negative life events with cognitive decline none of which were mediated by depressive symptoms. The death of a child or grandchild, which may be considered a highly stressful event, was associated to a higher rate of cognitive decline, whereas more chronic stressors, such as the illness of a partner or relative, or serious conflicts, were associated with better cognitive function. The associations between life events and cognitive function were stronger in ApoE ε4 carriers compared with noncarriers, suggesting that this gene plays a role in the association between stress and cognitive function. DISCUSSION: Highly stressful events seem to be associated with a higher rate of cognitive decline, whereas mild chronic stressors may have an arousing function that stimulates cognitive performance.