Anemia and Quality of Life: Unrecognized and Undertreated

IN this issue of the Journal of Gerontology: Medical Sciences, Cesari and colleagues report on the association of anemia in older adults with muscle density and muscle strength, as measured by ankle extension (1). This crosssectional analysis does not imply causality, but the association is strong. In this population, the prevalence of anemia was 10%. Participants who were anemic were older, had a higher prevalence of a stroke and gastric ulcer, used more medications, and had higher creatinine levels. These factors suggest that anemia may result from underlying disease; however, the association held even when these diseases were excluded. The report by Cesari and colleagues focuses attention on an often-unheralded condition—anemia—that contributes to morbidity in older adults. As clearly recognized in recent issues of the Journal, the development of frailty (5) and mobility impairment is multifactorial (2–4). Anemia has been associated with both frailty and mobility impairment (6). For example, women with a hemoglobin concentration between 13–14 g/dL have better mobility and lower mortality compared with those with a hemoglobin concentration of less than 12 g/dL (6). Anemia has been shown to lead to functional impairment (5,6), and is a risk factor for falls in older persons (7–9). Anemia is strongly associated with an increase in myocardial infarction and poor outcomes following an infarct (10). Prolonged anemia results in left ventricular hypertrophy (11). Quality of life is impaired in persons with anemia (12), which produces a high level of fatigue (13). In addition, anemia is an independent risk factor for increased mortality over 5 years (14). Despite the growing evidence of these poor outcomes associated with anemia in older persons, the diagnosis is often overlooked and, more important, undertreated. Hemoglobin and hematocrit values differ little between the healthy elderly population and the younger population. Thus, anemia is not a normal finding in older persons and hemoglobin concentration should not be adjusted downward in older persons (15,16). The World Health Organization defines anemia as a hemoglobin concentration of less than 13 g/dL in men and less than 12 g/dL in women. The prevalence of anemia increases with each decade of life over the age of 70. In the Established Population data for 3946 adults aged 71 years or older, hemoglobin concentration was inversely associated with age. In men and women aged 71–74 years, 9% were anemic. The proportion of anemic persons increased differentially with age, reaching 41% for men and 21% for women, aged 90 years or older, respectively (17). A similar trend was reported in the third National Health and Nutrition Examination Survey, where the prevalence jumps from 11% in males aged 70–79 years to 22% in males aged 80–89 years (18). There is a marked sex difference in the frequency of anemia. In a population-based study, among 618 persons older than 65 years, the corrected annual incidence of anemia was higher in men (90.3 per 1000 participants) than women (69.1 per 1000 participants) (19). The most common cause of anemia in one prevalence study of older persons was anemia of chronic disease, accounting for 35%–40% of cases. Iron deficiency anemia was responsible for between 8% and 15% of cases. Chronic kidney disease was responsible for 6%–8% of cases. Blood loss accounted for 7% and myelodysplasia for about 5%. Vitamin B12 deficiency was responsible for another 5%. As in most studies of older persons, a large number of anemias were undiagnosed despite evaluation (20). The management of anemia begins with a careful differential diagnosis. A corrected reticulocyte count is useful to determine bone marrow function. Anemia associated with an increased reticulocyte count occurs when the bone marrow responds to red cell destruction (hemolysis) or hemorrhage. The presence of elevated concentrations of unconjugated bilirubin and lactic dehydrogenase usually accompanies hemolysis. If these concentrations are normal, a source of blood loss should be sought. A stool occult blood should be obtained, as gastrointestinal bleeding is the most common cause of occult blood loss. A low or normal corrected reticulocyte count in the presence of anemia indicates an inadequate bone marrow response. In the presence of a low corrected reticulocyte count, determination of red cell morphology indices is useful. An elevated mean corpuscular volume (macrocytosis) suggests vitamin B12 or folate deficiency, hepatic disease, myelodysplasia, hypothyroidism, or alcoholism. Measurement of vitamin B12 and folate concentrations will determine anemia due to these causes in the majority of cases. Confirmation of vitamin B12 deficiency in those patients who have values in the lower normal range should be obtained, since about 50% of patients with subclinical disease may have normal B12 levels. A more sensitive method of screening for vitamin B12 deficiency is