Association between serum copper, zinc and hospital admissions among care home residents

Abstract

Nutritional status is important in various health care settings, long-term care is no exception. The relationship between protein-energy malnutrition and clinical outcomes in care homes has been reported. However, little is known about the roles of trace elements in clinical outcomes of care home residents. In 2002, 75 severely disabled care home residents (mean age: 77.7+/-8.2 years, 64.3% males) were enrolled for study. The status of protein-energy malnutrition at enrollment was as follows: 47.9% underweight (body mass index, BMI<20 kg/m(2)), 15.5% hypoalbuminemia (serum albumin <3.5 mg/dl), and 29.6% hypocholesterolemia (serum total cholesterol <160 mg/dl), respectively. During the 6-month follow-up, anthropometric measurements (i.e., BMI and mid-arm circumferences) remained similar, but the biochemical markers of nutritional status (i.e., albumin, total cholesterol) were significantly deteriorated, and both serum zinc and copper were significantly increased. Compared with subjects without hospitalizations during the follow-up period, subjects ever hospitalized had significantly lower mean serum levels of albumin (3.6+/-0.3 mg/dl vs. 3.9+/-0.3 mg/dl, p=0.002), zinc (74.3+/-12.1 vs. 89.6+/-20.5 microg/dl, p=0.020), and higher serum levels of copper (110.6+/-14.1 vs. 95.2+/-21.1 microg/dl, p=0.023) at baseline screening. Adjusted for age, sex, and protein-energy malnutrition, baseline serum copper (odds ratio=OR=1.08, 95% CI=1.02-1.15, p=0.015) and zinc (OR=0.92, 95% CI=0.84-1.00, p=0.053) were significant independent predictive factor for hospital admissions. In conclusion, adjusted for age, sex, and protein-energy malnutrition, serum levels of copper and zinc both were independent predictive factors for hospitalizations among care home residents. Further interventional study is needed to clarify the prognostic roles of serum copper and zinc among care home residents.