Effect of weight loss on mortality in overweight and obese nursing home residents during a 5-year follow-up.

BACKGROUND/OBJECTIVES: The objective of this study was to ascertain the effect of weight loss over the course of 1 year on 5-year mortality in old nursing home (NH) residents in different classes of body mass index (BMI). SUBJECTS/METHODS: A longitudinal study was conducted on 161 NH residents aged ⩾70 years at the Istituto di Riposo per Anziani, Padova, Italy. Data were collected using a comprehensive geriatric assessment at baseline and at a 1-year follow-up visit. Mortality was recorded over a 5-year follow-up. We divided our sample into four groups using as cutoffs a BMI of 25 and a weight gain or loss of 5% at 1 year (BMI ⩾25 and weight stable/gain, BMI ⩾25 and weight loss, BMI<25 and weight stable/gain and BMI <25 and weight loss). RESULTS: People with a BMI ⩾25 and weight loss suffered the worst decline in activities of daily living, whereas those with a BMI <25 and weight loss had the most significant decline in nutritional status, which coincided with the worst decline in the Multidimensional Prognostic Index among the groups whose weight changed. Compared with those with a BMI ⩾25 and weight stable/gain (reference group), those with a BMI <25 were at the highest risk of dying (in association with weight loss: hazard ratio HR=3.60, P=0.005; in association with weight stable/gain: HR=2.45, P=0.01), and the mortality risk was also increased in people with a BMI ⩾25 and weight loss (HR=1.74, P=0.03). CONCLUSIONS: In conclusion, weight loss increases the mortality risk in frail, disabled NH residents, even if they are overweight or obese.