Changes in community mobility in older men and women. A 13-year prospective study.

Community mobility, defined as "moving [ones] self in the community and using public or private transportation", has a unique ability to promote older peoples' wellbeing by enabling independence and access to activity arenas for interaction with others. Early predictors of decreased community mobility among older men and women are useful in developing health promoting strategies. However, long-term prediction is rare, especially when it comes to including both public and private transportation. The present study describes factors associated with community mobility and decreased community mobility over time among older men and women. In total, 119 men and 147 women responded to a questionnaire in 1994 and 2007. Respondents were between 82 and 96 years old at follow-up. After 13 years, 40% of men and 43% of women had decreased community mobility, but 47% of men and 45% of women still experienced some independent community mobility. Cross-sectional independent community mobility among men was associated with higher ratings of subjective health, reporting no depression and more involvement in sport activities. Among women, cross-sectional independent community mobility was associated with better subjective health and doing more instrumental activities of daily living outside the home. Lower subjective health predicted decreased community mobility for both men and women, whereas self-reported health conditions did not. Consequently, general policies and individual interventions aiming to improve community mobility should consider older persons' subjective health.

The type A behavior pattern and cardiovascular disease as predictors of dementia.

OBJECTIVE: Research has suggested that greater psychophysiological reactivity to stress increases risk of dementia and that those with the Type A behavior pattern (TABP) are predisposed to elevated stress reactivity and cardiovascular disease (CVD), but no study has evaluated the associations among TABP, CVD, and dementia, prospectively. Hence, the present study aimed to investigate dementia risk in relation to TABP and CVD. METHODS: A population-based cohort of 1,069 persons with a baseline mean age of 64.81 years from the Swedish Twin Registry was followed consecutively for up to 23 years. Based on self-reported items, TABP was measured using 6 scales: Ambition, Stress, Hard-driving, Neuroticism, Cynicism, and Paranoia. CVD was self-reported and dementia was diagnosed adhering to Diagnostic and Statistical Manual of Mental Disorders, third edition, revised (DSM-III-R) or Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV) criteria. RESULTS: TABP was generally not associated with dementia risk. However, significant interaction effects of stress, paranoia, and cynicism with CVD on dementia risk were observed. That is, for those with CVD, high scores on stress, paranoia, and cynicism were associated with increased risk of dementia (hazard ratio [HR] = 1.43, 95% confidence interval [CI] = 0.95-2.15; HR = 1.39, 95% CI = 0.83-2.33; HR = 1.25, 95% CI = 0.76-2.06, respectively), whereas for those who did not have CVD, high scores on these measures appeared to be protective (HR = 0.76, 95% CI = 0.50-1.14; HR = 0.55, 95% CI = 0.34-0.89; HR = 0.50, 95% CI = 0.29-0.84, respectively). CONCLUSION: Some features of TABP confer an increased risk for dementia in those with CVD, whereas those without CVD are protected. When evaluating the risk of dementia, CVD and personality traits should be taken into consideration.

Accuracy of recalled body weight--a study with 20-years of follow-up.

OBJECTIVE: Weight changes may be an important indicator of an ongoing pathological process. Retrospective self-report might be the only possibility to capture prior weight. The objective of the study was to evaluate the accuracy of retrospective recall of body weight in old age and factors that might predict accuracy. DESIGN AND METHODS: In 2007, 646 participants (mean age, 71.6 years) of the Swedish Adoption/Twin Study of Aging (SATSA) answered questions about their present weight and how much they weighed 20-years ago. Of these, 436 had self-reported their weight twenty years earlier and among these 134 had also had their weight assessed at this time point. RESULTS: Twenty year retrospectively recalled weight underestimated the prior assessed weight by -1.89 ± 5.9 kg and underestimated prior self-reported weight by -0.55 ± 5.2 kg. Moreover, 82.4% of the sample were accurate within 10%, and 45.8% were accurate within 5% of their prior assessed weights; similarly, 84.2% and 58.0% were accurate within 10% and 5% respectively, for prior self-reported weight. Current higher body mass index and preferences of reporting weights ending with zero or five was associated with an underestimation of prior weight, while greater weight change over 20 years, and low Mini-Mental State Scores (MMSE) (<25) led to an overestimation of prior weight. CONCLUSIONS: Recalled weight comes close to the assessed population mean, but at the individual level there is a large variation. The accuracy is affected by current BMI, changes in weight, end-digit preferences, and current cognitive ability. Recalled weight should be used with caution.

Body mass index, change in body mass index, and survival in old and very old persons.

OBJECTIVES: To examine how body mass index (BMI) and change in BMI are associated with mortality in old (70-79) and very old (≥80) individuals. DESIGN: Pooled data from three multidisciplinary prospective population-based studies: OCTO-twin, Gender, and NONA. SETTING: Sweden. PARTICIPANTS: Eight hundred eighty-two individuals aged 70 to 95. MEASUREMENTS: BMI was calculated from measured height and weight as kg/m(2) . Information about survival status and time of death was obtained from the Swedish Civil Registration System. RESULTS: Mortality hazard was 20% lower for the overweight group than the normal-underweight group (relative risk (RR) = 0.80, P = .011), and the mortality hazard for the obese group did not differ significantly from that of the normal-underweight group (RR = 0.93, P = .603), independent of age, education, and multimorbidity. Furthermore, mortality hazard was 65% higher for the BMI loss group than for the BMI stable group (RR = 1.65, P < .001) and 53% higher for the BMI gain group than for the BMI stable group (RR = 1.53, P = .001). Age moderated the BMI change differences. That is, the higher mortality risks associated with BMI loss and gain were less severe in very old age. CONCLUSION: Old persons who were overweight had a lower mortality risk than old persons who were of normal weight, even after controlling for weight change and multimorbidity. Persons who increased or decreased in BMI had a greater mortality risk than those who had a stable BMI, particularly those aged 70 to 79. This study lends further support to the belief that the World Health Organization guidelines for BMI are overly restrictive in old age.

Obesity and cognitive aging.

Obesity is a health problem that has reached epidemic proportions. Given the high prevalence of obesity, even a small adverse impact of obesity on cognitive aging might have a serious effect on public health. The purpose of this systematic review was to examine the relation between obesity and cognitive function in late life among persons not diagnosed with dementia and to evaluate the evidence for a causal association. Medline was used to search for the following terms: obesity, overweight, cognition, cognitive, age, and aged. To be included, studies must have had a population-based, dementia-free sample and a 5-year minimum interval between measurement of the predictor and the outcome. Only 11 studies met the criteria. Of these, 7 studies assessed obesity in midlife and cognitive function in later life, and 4 studies assessed obesity and cognitive function in late life. The reviewed studies showed clear evidence that midlife obesity was associated with cognitive aging, whereas this association was weaker in late life; thus, no firm conclusions could be drawn. The findings of this review suggest that, although there is evidence for an association between midlife obesity and low cognitive abilities in late life, the direction of the association and the causality remain to be clarified.

IGEMS: the consortium on Interplay of Genes and Environment across Multiple Studies.

The Interplay of Genes and Environment across Multiple Studies (IGEMS) group is a consortium of eight longitudinal twin studies established to explore the nature of social context effects and gene-environment interplay in late-life functioning. The resulting analysis of the combined data from over 17,500 participants aged 25-102 at baseline (including nearly 2,600 monogygotic and 4,300 dizygotic twin pairs and over 1,700 family members) aims to understand why early life adversity, and social factors such as isolation and loneliness, are associated with diverse outcomes including mortality, physical functioning (health, functional ability), and psychological functioning (well-being, cognition), particularly in later life.

Overweight in midlife is related to lower cognitive function 30 years later: a prospective study with longitudinal assessments.

AIM: To examine if the body mass index (BMI) in midlife is related to cognitive function 30 years later in a dementia-free sample. METHODS: BMI was reported in 1963 at age 50-60 years, and cognitive abilities were examined 30 years later in a longitudinal design with 5 measurement occasions at 2-year intervals (n = 417). The cognitive abilities examined included tests of long-term memory, short-term memory, speed, verbal and spatial ability. RESULTS: Multilevel modeling adjusting for demographic and lifestyle factors, and relevant diseases showed that a higher BMI in midlife predicted lower test performance 30 years later. Significant associations between BMI and level of performance were found in all cognitive abilities; however, a higher midlife BMI was not associated with steeper cognitive decline. CONCLUSION: Our results indicate that midlife overweight is related to lower overall cognitive function in old age. The fact that BMI-related effects were noted in mean-level cognitive performance, whereas only one ability showed differences in slopes, suggests that the negative effect of overweight has an onset before the entry into very old age.

Agreement between self-reported and measured height, weight and body mass index in old age--a longitudinal study with 20 years of follow-up.

BACKGROUND: self-reported body mass index (BMI) based on self-reported height and weight is a widely used measure of adiposity in epidemiological research. Knowledge about the accuracy of these measures in late life is scarce. OBJECTIVE: the study aimed to evaluate the accuracy and changes in accuracy of self-reported height, weight and BMI calculated from self-reported height and weight in late life. DESIGN: a longitudinal population-based study with five times of follow-up was conducted. PARTICIPANTS: seven hundred seventy-four community-living men and women, aged 40-88 at baseline (mean age 63.9), included in The Swedish Adoption/Twin Study of Aging. METHODS: participants self-reported their height and weight in a questionnaire, and height and weight were measured by experienced research nurses at an in-person testing five times during a 20-year period. BMI was calculated as weight (kilogramme)/height (metre)(2). RESULTS: latent growth curve modelling showed an increase in the mean difference between self-reported and measured values over time for height (0.038 cm/year) and BMI (0.016 kg/m(2)/year), but not for weight. CONCLUSIONS: there is a very small increase in the mean difference between self-reported and measured BMI with ageing, which probably would not affect the results when self-reported BMI is used as a continuous variable in longitudinal studies.

Overweight and obesity in old age are not associated with greater dementia risk.

OBJECTIVES: To describe the association between body mass index (BMI) and dementia risk in older persons. DESIGN: Prospective population-based study, with 8 years of follow-up. SETTING: The municipality of Lieto, Finland, 1990/91 and 1998/99. PARTICIPANTS: Six hundred five men and women without dementia aged 65 to 92 at baseline (mean age 70.8). MEASUREMENTS: Weight and height were measured at baseline and at the 8-year follow-up. Dementia was clinically assessed according to Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, criteria. RESULTS: Eighty-six persons were diagnosed with dementia. Cox regression analyses, adjusted for age, sex, education, cardiovascular diseases, smoking, and alcohol use, indicated that, for each unit increase in BMI score, the risk of dementia decreased 8% (hazard ratio (HR)=0.92, 95% confidence interval (CI)=0.87-0.97). This association remained significant when individuals who developed dementia early during the first 4 years of follow-up were excluded from the analyses (HR=0.93, 95% CI=0.86-0.99). Women with high BMI scores had a lower dementia risk (HR=0.90, 95% CI=0.84-0.96). Men with high BMI scores also tended to have a lower dementia risk, although the association did not reach significance (HR=0.95, 95% CI=0.84-1.07). CONCLUSION: Older persons with higher BMI scores have less dementia risk than their counterparts with lower BMI scores. High BMI scores in late life should not necessarily be considered to be a risk factor for dementia.