Anemia: an indicator for malnutrition in the elderly

Abstract

The prevalence of anemia increases with age and is frequently multifactorial. We postulated that malnutrition contributes to anemia in the elderly and is underdiagnosed. Our objective was to analyze the prevalence of anemia and its association with nutritional status in a hospitalized geriatric population. Included in this retrospective cohort study were 186 consecutive patients admitted in 1997 to a geriatric unit of a university hospital. We compared hematological and chemical blood tests routinely performed upon admission in patients with anemia (hemoglobin <120 g/l) and without anemia (hemoglobin > or = 120 g/l). Using these admission parameters, we defined a multiparameter score of malnutrition by low lymphocyte counts, decreased values of albumin, cholesterol, transferrin, cholinesterase, and zinc, iron deficiency by low transferrin saturation and normal C-reactive protein, and inflammation by increased C-reactive protein and high transferrin saturation. Of the 186 patients, 82 (44%) met the criteria for anemia on admission. In univariate analysis, patients with anemia differed significantly from patients with normal hemoglobin exhibiting lower serum values of albumin, iron, transferrin, cholesterol, cholinesterase, zinc, transferrin saturation, and lymphocyte count and higher C-reactive protein levels. Using a multiparameter score, anemia correlated significantly with parameters of malnutrition (P=0.0001) but not with iron deficiency (P=0.5) or with inflammation (P=0.08). In a multivariate logistic regression model, anemia was significantly associated with serum albumin (RR: 1.138; 95% CI: 1.056-1.227; P=0.0007), cholinesterase (RR: 1.387; 95% CI 1.122-1.714; P=0.0025), and transferrin saturation (RR: 1.05; 95% CI: 1.012-1.09; P=0.009). We conclude that malnutrition may play an important etiologic role in anemia in the elderly.