Anthropometric and biochemical markers for nutritional risk among residents within an Austrlaian residential care facility

Abstract

The risk of malnutrition is high among elderly population, yet few studies have measured indicators of nutritional status among Australian aged-care residents. To determine the relationship between nutritional status and bone density, hand grip strength, and the timed-up and go test, in a group of Australian aged-care residents. Anthropometric and biochemical analysis measured in subjects recruited to be part of a six month multivitamin supplementation study. One hundred and fifteen subjects participated (68% female). The mean (SD) age and body weight was 80.2(10.6) years, and 66.5(15.0) kg, respectively. Eleven percent were underweight (body mass index, BMI, ≤20.0kg/m²), and 20% were obese BMI ≥30kg/m²). Low serum 25-hydroxy-vitamin D (25(OH)D, ≤50 nmol/L) concentrations were found among 79% of subjects. After adjustment for body weight, there was an association between serum 25(OH)D and bone density (heel ultrasound) (r=.204, p=.027). Low serum zinc (≤10.7 μmol/L) concentrations were found among 46% of subjects; this group had a slower timed up and go time compared with those with higher zinc concentrations (n=19, 44.6 ± 5.6 seconds vs. n=27, 30.0 ± 3.3 seconds, p=.020). There were no associations between nutritional markers and hand grip strength. In this group, more than ¾ of subjects had low serum 25(OH)D, and 46% had low zinc concentrations. Serum 25(OH)D was associated a lower bone density and zinc with a slower walking time. This indicates that the elderly in long term residential care facilities are at high risk for poor nutritional status, potentially increasing morbidity and mortality.