Nutritional status ‘multifactorial’ in institutionalized elderly
MedWire News: Dementia, energy expenditure, and immobility all impact nutritional status among institutionalized elderly people, a study by Brazilian researchers shows.
The team says that elderly individuals ought to have all of these three factors measured in order to gain a complete understanding of their nutritional needs.
Vânia Leandro-Merhi (Pontifícia Universidade Católica de Campinas, São Paolo, Brazil) and team recruited 150 men and women living in a long-term institutional care home. The mean age was 73 years in men and 80 years in women.
Based on body mass index (BMI) alone and using a cutpoint of 22 kg/m2, 64% of the cohort was classified as nourished and 36% as malnourished.
Also, nearly half of the participants had dementia (diagnosed using the Mini-Mental State Examination), with the prevalence being higher in women (59%) than in men.
Interestingly, among women, the prevalence of dementia did not vary by nutritional status and women with dementia formed the majority in both nourished and malnourished groups.
By contrast, among men, dementia was significantly more prevalent in malnourished versus nourished individuals.
In an analysis looking at biochemical and anthropometric variables, as well as energy and nutrient intake, just two factors differed significantly between individuals with and without dementia.
The first was muscle mass, which differed only in men. Four measures of muscle mass - BMI, mid-arm circumference, mid-arm muscle circumference, and calf circumference - were all significantly lower in men with dementia than in those without the condition.
The second was vitamin C intake, which differed only in women. Mean daily vitamin C intake was 41.8 mg in women with dementia versus 32.2 mg in women without dementia.
Writing in the International Journal of Older People Nursing, the researchers hypothesize that "the established relationship between dementia and nutritional status may be explained, not by food intake, but by the weight loss that results from activities in individuals with dementia that require more energy, such as agitation and walking about, including periods of extreme physical activity."
They note, however, that there are other "organic" reasons for weight loss, such as medial temporal lobe atrophy caused by eating behavior, immobility that increases the incidence of pressure ulcers, and infections, which increase nutritional needs, cause muscle atrophy and reduce orexigenic peptides.
The team concludes: "Investigation of dementia can improve the accuracy of the nutritional assessment of older people. Instruments for the nutritional assessment of individuals with dementia should also investigate energy expenditure and immobility as this would provide a more complete assessment of this population."
By Joanna Lyford