[The prevalence and etiology of anemia in urban community dwelling elderly population in Beijing].

OBJECTIVE: To estimate the prevalence of anemia in urban community dwelling elderly population.

METHODS: This study was a cross-sectional survey of prevalence of anemia in randomly selected community dwelling residents aged over 65 years in Beijing. Anemia was defined as hemoglobin concentration less than 130 g/L in men and 120 g/L in women.

RESULTS: The hemoglobin concentration was (135.65±14.48) g/L in total of 1 947 eligible participants and was much higher in men than in women [(142.56±15.56) g/L vs (130.95±11.53) g/L, P<0.001]. There were 288 (14.8%) patients with anemia, including 16.3%(129/789) in men and 13.7%(159/1 158) in women. The prevalence of anemia increased significantly with age, which was 7.6% in 65-69 years, 10.8% in 70-74 years, 18.8% in 75-79 years and 24.1% over 80 years (P<0.001). Two hundred and seventy-nine (96.9%) subjects were mild anemia, 8 (2.8%) moderate, only 1 subject (0.3%) severe. Unexplained anemia was predominant, which accounted for 63.2%. Only 16.7% people were diagnosed as nutritional anemia, renal anemia 5.2%, anemia of chronic disease (ACD) 12.2%. There were 2.4% people with overlapped renal anemia and ACD. Compared with non-anemic subjects, more subjects with unexplained anemia represented macrocytosis (7.1% vs 3.2%, P=0.007).

CONCLUSIONS: Anemia is a common health problem in urban community dwelling elderly population. Most subjects have anemia with unknown origin. Further investigation is needed to explore the mechanism and related factors of elderly anemia.