Prevalence of malnutrition and risk factors in geriatric patients of a convalescent and rehabilitation hospital

Abstract

Objectives: To investigate the prevalence and risk factors of malnutrition in geriatric patients admitted to a convalescent and rehabilitation hospital.

Design: Cross-sectional study.

Setting: Regional hospital, Hong Kong.

Patients: A total of 120 patients (aged 60 years or older) referred to Tung Wah Eastern Hospital.

Main outcome measures: Anthropometric, biochemical, and haematological parameters were measured for nutritional assessment. Malnutrition was defined as a body mass index of lower than 18.5 kg/m(2) and serum albumin level of lower than 35 g/L. The clinical outcomes of patients were also recorded. The predictive value of the Chinese Mini Nutritional Assessment as a nutritional screening tool was assessed. Potential risk factors associated with malnutrition were evaluated according to established protocols.

Results: The mean age of patients was 80.3 years (standard deviation, 7.4 years), and the mean body mass index was 21.9 kg/m(2) (standard deviation, 4.4 kg/m(2)). The prevalence of malnutrition was 16.7%. The age distribution of malnourished patients (mean, 86.2 years; standard deviation, 7.0 years; n=20) was significantly different to those nourished (mean, 79.1 years; standard deviation, 6.9 years; n=100) [P=0.0001]. Mortality was also higher in malnourished patients (25%) than nourished patients (4%) [P=0.001]. Based on the Chinese Mini Nutritional Assessment, 16.9% of patients were classified as malnourished (cut-off value, 18.5). The Chinese Mini Nutritional Assessment was useful as a screening tool to exclude patients who were not malnourished, ie it had a high negative predictive value (95%). Being totally dependent for the performance of activities of daily living, living in a home for the elderly, and being chair- or bed-bound posed a significantly increased risk of malnutrition. The presence of mental depression (geriatric depression scale score of 8 or higher), moderately or severely impaired cognitive function (abbreviated mental test score of lower than 7), or polypharmacy (five medications or more) did not significantly affect risk of malnutrition.

Conclusions: Malnutrition was common in the geriatric patients studied and was associated with an increased mortality. The Chinese Mini Nutritional Assessment was a useful screening tool to exclude malnutrition. Significant risk factors of malnutrition were total dependence, living in a home for the elderly, and being chair- or bed-bound.