A 32-Year Prospective Study of Change in Body Weight and Incident Dementia

Abstract

Background: The course of weight loss associated with dementia is unclear, particularly prior to and around the onset of the clinical syndrome.Objective: To compare the natural history of weight change from mid to late life in men with and without dementia in late life. Design and Setting:The Honolulu-Asia Aging Study, a 32-year, prospective, population-based study of Japanese American men who had been weighed on 6 occasions between 1965 and 1999 and who had been screened for dementia 3 times between 1991 and 1999.Participants: Of 1890 men (aged 77-98 years), 112 with incident dementia were compared with 1778 without dementia at the sixth examination (1997)(1998)(1999).Main Outcome Measure: Weight change up to and including the sixth examination was treated as the dependent variable and estimated using a repeated measures analysis.Results: Groups with and without dementia did not differ with respect to baseline weight or change in weight from mid to late life (first 26 years' follow-up). In the latelife examinations (final 6 years), mean age-and educationadjusted weight loss was −0.22 kg/y (95% confidence intervals, −0.26 to −0.18) in participants without dementia. Men with incident dementia at the same examination had an additional yearly weight loss of −0.36 kg (95% confidence interval, −0.53 to −0.19). This was not changed substantially with adjustment for risk factors for vascular disease or functional impairment and was significant for both Alzheimer disease and vascular dementia subtypes.Conclusions: Dementia-associated weight loss begins before the onset of the clinical syndrome and accelerates by the time of diagnosis. The potential impact on prognosis should be considered in the case of elderly persons at risk for dementia.

Weight Change in Midlife and Risk of Mortality From Dementia up to 35 Years Later

“…We identified five studies which have, like us, linked weight change from midlife into old age to dementia outcomes, and in accordance with our findings, weight loss was associated with increased dementia risk in all these studies (14,(17)(18)(19)28). First, in the Honolulu-Asia Aging Study, a study of Japanese American men, where age at inclusion was from late 40s and 60s and follow-up was until 90s for the oldest, it was reported that men that developed dementia lost significantly more weight during the years prior to the diagnosis, especially during the three year period prior to the diagnosis (14).…”

“…Our result regarding weight loss being associated with increased dementia related mortality risk fits with studies using clinical dementia as end point (10)(11)(12)(13)(14)(15)(16)(17)(18). Most previous studies investigate weight change in old age, typically above 65 years or older, where reverse causality might be a plausible explanation for the association between weight loss and dementia.…”

“…First, in the Honolulu-Asia Aging Study, a study of Japanese American men, where age at inclusion was from late 40s and 60s and follow-up was until 90s for the oldest, it was reported that men that developed dementia lost significantly more weight during the years prior to the diagnosis, especially during the three year period prior to the diagnosis (14). Secondly, in the Baltimore…”

“…A better understanding of the association between body weight and dementia may be achieved by studying weight trajectories and patterns from midlife into old age (1). Studies with weight at multiple time points have generally reported weight loss (10)(11)(12)(13)(14)(15)(16)(17)(18) or weight instability (19) to be associated with increased dementia risk. However, many of these studies are limited to weight trajectories in old age, and might be prone to reverse causality because dementia and preclinical dementia might cause weight loss (1,20).…”

Body mass index, dementia, and mortality in the elderly

“…cancer, smoking, heart disease) are not important confounders in the association between low BMI and mortality, or that there is residual or unmeasured confounding by other conditions 6 . We sought to explore whether dementia, which is associated with weight loss 30 , lower BMI 9 , and higher mortality 1,[31][32][33][34][35] , could explain the association between low BMI and mortality. Dementia may cause weight loss and lower BMI due to feeding difficulties 7 and other catabolic changes that are not totally understood.…”