Anemia and cognitive performance in hospitalized older patients: results from the GIFA study

BACKGROUND: Anemia represents a major risk factor for adverse health-related events in older persons. The aim of this study was to evaluate the association between hemoglobin levels/anemia and cognitive function in hospitalized older persons. METHOD: Data are from the Gruppo Italiano di Farmacovigilanza nell'Anziano (GIFA) study. Hemoglobin levels (in g/dL) were measured upon admission to hospital; anemia was defined according to the WHO criteria. Cognitive performance was assessed by the Abbreviated Mental Test (AMT) on admission; an AMT score <7 defined cognitive impairment. Logistic regressions and analyses of covariance were performed to evaluate the relationship between cognitive status and hemoglobin levels/anemia. RESULTS: Mean age of the sample (n = 13,301) was 72.0 years. Participants with cognitive impairment presented a higher prevalence of anemia (47%) compared to those without cognitive impairment (35%, p < 0.001). Adjusted logistic regressions showed that hemoglobin levels/anemia were significantly associated with cognitive impairment (OR = 0.96, 95%CI = 0.94-0.99, p = 0.004, and OR = 1.32, 95%CI = 1.18-1.48, p < 0.001, respectively). Patients with anemia and cognitive impairment at the hospital admission presented a higher number of impaired Activities of Daily Living compared to those with only one or none of the studied conditions (p for trend < 0.001). CONCLUSION: Low hemoglobin levels and anemia are independently associated with cognitive performance in older persons admitted to acute care units.