INCIDENCE OF ANEMIA IN OLDER-PEOPLE - AN EPIDEMIOLOGIC-STUDY IN A WELL-DEFINED POPULATION

OBJECTIVE: To assess the incidence and clinical spectrum of anemia amo ng older people. DESIGN: Inception cohort assembled and followed by me dical records linkage until death or last clinical contact through Jan uary 1994. SETTING: Population-based study in Olmsted County, Minnesot a. PARTICIPANTS: All 618 Olmsted County men and women aged 65 years or more with anemia by World Health Organization criteria that was first recognized in 1986. MEASUREMENTS: Age- and sex-adjusted incidence rat es, corrected for prevalent anemia, and survival estimates using the K aplan-Meier method, with calculation of standardized mortality ratios for specific causes of death. RESULTS: The corrected annual incidence of anemia rose with age, and rates were higher in men (90.3 per 1000; 95% CI, 79.2-101.4) than women (69.1 per 1000; 95% CI, 62.3-75.8). In 465 cases (75%), anemia was detected in conjunction with a hospitaliza tion, but admission was due to anemia in only 57 instances. Half of th e cases were caused by blood loss, two-thirds of these as a result of surgery. The cause of anemia was uncertain in 102 cases (16%). One-thi rd of the patients were transfused with a median of 3 units each. Over all survival was worse than expected but was better among those with a nemia caused by blood loss. Mortality attributable to malignancy, ment al disorders, circulatory and respiratory diseases, ill-defined condit ions, and injuries was significantly increased among these older patie nts with anemia. CONCLUSIONS: The incidence of anemia among older peop le is 4 to 6 times greater than that suspected clinically, rises with age, and is higher in men than in women. The apparent cause in half th e cases is blood loss. Even mild anemia is associated with reduced sur vival, especially during the first year, but this could relate to unde rlying comorbid conditions.