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 in midlife and risk of dementia: a 40-year follow-up study

OBJECTIVE

This study examines whether overweight in midlife increases dementia risk later in life.

METHODS

In 1963 body mass index was assessed in 1152 participants of The Swedish Twin Registry, at the age of 45-65 years. These participants were later screened for dementia in a prospective study with up to 40 years follow-up. A total of 312 participants were diagnosed with dementia.

RESULTS

Logistic regression analyses adjusted for demographic factors, smoking and alcohol habits, indicated that men and women categorized as overweight in their midlife had an elevated risk of dementia (OR=1.59; 95% CI: 1.21-2.07, P=0.002), Alzheimer's disease (OR=1.71; 95% CI: 1.24-2.35, P=0.003), and vascular dementia (OR=1.55; 95% CI: 0.98-2.47, P=0.059). Further adjustments for diabetes and vascular diseases did not substantially affect the associations, except for vascular dementia (OR=1.36; 95% CI: 0.82-2.56, P=0.116), reflecting the significance of diabetes and vascular diseases in the etiology of vascular dementia. There was no significant interaction between overweight and APOE epsilon4 status, indicating that having both risk factors does not have a multiplicative effect with regard to dementia risk.

CONCLUSIONS

This study gives further support to the notion that overweight in midlife increases later risk of dementia. The risk is increased for both Alzheimer's disease and vascular dementia, and follows the same pattern for men and women.

What matters for life satisfaction in the oldest-old?

The purpose of this study was to examine factors associated with life satisfaction in the oldest-old within a spectrum of psychosocial and health related variables. Scores on the life satisfaction index (LSI-Z) were related to scales and questions regarding, demographics, depression, locus of control, cognitive function, functional capacity (instrumental and personal activities of daily living), self-rated overall health and medically based health, and social network. The sample consisted of 315 participants, aged 80-98 years; (M = 83 years, 66% women). Regression analyses indicated that social network quality, self-rated overall health, sense of being in control of one's life, and depressive symptoms were significantly associated with life satisfaction. There was no gender difference in overall life satisfaction. However, there were different patterns of variables associated with life satisfaction in men and women. Self-rated overall health and depressive symptoms were related to life satisfaction in women, whereas widowhood was significantly associated with lower life satisfaction among men. The results emphasize the need to analyse associates of life satisfaction within a broader context of psychosocial variables and separately for men and women.