Protein-energy undernutrition and life-threatening complications among the hospitalized elderly.

Abstract

To determine whether elderly patients with protein-energy undernutrition at admission are at increased risk for subsequent life-threatening events after controlling for illness severity. Prospective cohort study. University-affiliated Department of Veterans Affairs hospital. Five hundred eighty-six nonterminal patients (mean age 74 +/- 6 [SD] years, 98% male, 86% white) with a length of stay of 3 days or more. Life-threatening complications. Subsequent to admission, 37 subjects (6.3%) experienced at least 1 life-threatening complication. All of the putative nutrition variables examined and many non-nutrition, illness severity measures were strongly correlated with the risk of a life-threatening complication by univariate analyses (P <.05 for all analyses). After controlling for illness severity, admission serum albumin, prealbumin, and cholesterol were no longer significantly correlated with the outcome. In contrast, weight loss (>5% within 6 months), body mass index, mid-arm circumference, and suprailiac skinfold thickness remained strong independent predictors. The adjusted relative risk of a life-threatening complication ranged from 2.9 (95% confidence interval [CI], 1.3 to 6.4) for a body mass index <22 kg/m2 to 7.1(95% CI, 2.0 to 25.7) for a suprailiac skinfold thickness in the lower tertile for the study population. The putative nutrition and illness severity variables were highly intercorrelated. There is a complex interrelationship between nutritional status, illness severity, and clinical outcomes among the hospitalized elderly. The serum secretory proteins and cholesterol are correlated with other indicators of illness severity and adverse outcomes, but may not be good markers of nutritional risk. In contrast, weight loss, a low body mass index, and other indicators of lean and fat mass depletion appear to place the patient at increased risk for adverse outcomes independent of illness severity. Whether it is possible to reverse such established nutritional deficits and reduce complication risk in the acute care setting remains to be determined.