Malnutrition in Very Old Hospitalized Patients: A New Etiologic Factor of Anemia?

backgroundAnemia and malnutrition are highly prevalent, frequently concomitant and associated with negative outcomes and mortality in the elderly.

objectivesTo evaluate the association between these two entities, and test the hypothesis that protein-energy deficit could be etiology of anemia.

designProspective case-control study.

settingGeriatric and Rehabilitation Hospital, Geneva University Hospitals, Switzerland.

participants392 patients (mean age 84.8 years old, 68.6% female).

main outcome measuresHematological (hemoglobin (Hb)), chemical (iron work up, cyanocobalamin, folates, renal function, C-Reactive Protein (CRP)) and nutrition (albumin, prealbumin) parameters, and mini nutritional assessment short form (MNA-SF).

resultsThe prevalence of anemia (defined as Hb<120 g/l) was 39.3%. Anemic patients were more frequently malnourished or at risk of malnutrition according to the MNA-SF (p=0.047), with lower serum albumin (p <0.001) and prealbumin (p <0.001) levels. Thirty-eight percent of these patients had multiple causes and 14.3% had no cause found for anemia. Among the latter 90.9% of patients with unexplained anemia had albumin levels lower than 35g/l. After exclusion of iron,vitamin B12 and folic acid deficits, anemic patients had lower albumin (p<0.001) and prealbumin (p 0.007) levels. Albumin level explained 84.5% of the variance in anemia. In multivariate analysis albumin levels remain associated with Hb only in anemic patients, explaining 6.4% of Hb variance (adj R2) and 14.7% (adj R2) after excluding inflammatory parameters (CRP>10).

conclusionsAlbumin levels are strongly associated with anemia in the elderly. Screening for undernutrition should be included in anemia assessment in those patients. Further prospective studies are warranted in order to explore the effect of protein and energy supplementation on hemoglobin level.