Dementia severity and weight loss: A comparison across eight cohorts. The 10/66 study

Abstract

BackgroundWe aimed to investigate the association between dementia severity and weight loss in countries with low and middle incomes, where most prevalent cases reside.MethodsCross-sectional catchment area surveys were performed in Cuba, Mexico, Venezuela, Peru, Dominican Republic, Puerto Rico, China, and India. In 16,538 older adults (≥65 years of age), significant weight loss was self-reported and confirmed by an informant. We conducted neuropsychological testing and clinical and neurological assessments. Dementia severity was determined by applying a validated algorithm and was quantified by the Clinical Dementia Rating Scale.ResultsThe characteristics of those who reported weight loss varied across countries. In Poisson models, after controlling for relevant covariates and for waist and arm circumferences, dementia severity was associated with reported weight loss (pooled prevalence ratios [95% confidence intervals {CI}] 2.19 [1.98, 2.41]; 3.81 [3.35, 4.33]; and 5.18 [4.41, 6.10] for CDR 0.5, 1, and 2/3, respectively, compared with CDR 0). The association increased linearly through stages of dementia severity in all countries (P for trend < .001), and between-country heterogeneity was minimal.ConclusionsWe found a strong gradient effect in the direct association between dementia severity and reported weight loss, homogeneous across sites from eight countries, consistent with mechanistic data on the role of neurodegenerative processes on energy balance and with dietary changes due to disease severity. Considering the well-recognized effect of weight loss on morbidity and mortality and the large number affected by dementia in less resourced countries, amelioration of weight loss in dementia patients should be considered with priority in these settings.

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

“…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.…”

“…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).…”

ESPEN guidelines on nutrition in dementia

“…Weight loss is present in the initial stages of the disease, beginning even before diagnosis of the disease, and becoming more common with its progression. Evidence from the international 10/66 study confirms that the association between dementia and weight loss increases through the stages of dementia severity, and that geographical variations across diverse regions of the world are essentially negligible [18].…”

“…Regarding general nutritional status, a close relation between weight loss [18,43,54] as well as BMI [55,56] and disease severity is documented in older patients with dementia. There are also several prospective observational studies available which have demonstrated that weight loss [43,57,58] and malnutrition [59,60] are associated with disease progression and cognitive decline.…”

Obesity in Indian subjects with vascular dementia

“…24,25 However certain studies have reported weight loss and not obesity as a predictor of incident dementia suggesting a possible protective role especially for late life obesity. 26,27 As obesity is widely prevalent in India and vascular dementia is the second most common types of dementia in clinical practice in India, we decided to investigate the phenomenon of obesity in Indian subjects with vascular dementia.…”