[Causes, diagnosis, and treatment of anemia in the elderly]

Healthy elderly people are mildly anemic peripheral blood data on 3,583 healthy elderly people (1,590 men and 1,993 women aged 65 years or older) from among those undergoing medical examinations at our hospital in the 8 years from 1988 to 1995 were compiled into 5-year age groups. For both men and women the mean values of red blood cell count, hemoglobin, and hematocrit were slightly lower among older subjects. The main causes of this apparent reduction may be a decrease in the number of hematopoietic stem cells and regression of the hematopoietic microenvironment. Observation of arteries in specimens of hematopoietic bone marrow obtained from the spines of elderly people showed arteriosclerotic changes such as greater hypertrophy of the media than of the intima, and adventitial fibrous hypertrophy. The number of venous sinuses was low and the amount of adipose tissue was high compared to the bone marrow of younger people. The cell density and the ratio of hematopoietic tissue to fat tended to be lower in older subjects. The number of erythroid burst-forming units formed after 14 days in culture medium containing erythropoietin was 28 +/- 19 in 32 healthy elderly people, which was significantly lower than the number in 30 young people 54 +/- 30, (p < 0.005). The value for erythroid colony-forming units was 170 +/- 67 in eight healthy people, which was much lower than in young people, 276 +/- 54. In the elderly subjects, the plasma iron disappearance time (PIDT/2) was 60-80 min (mean: 71.9 min), which was similar to that in the young, but the percent red cell iron utilization was 67.6%-84.9% (mean: 79.7%), which was slightly lower than in younger people. When the diagnostic criterion for anemia in the elderly was set at a hemoglobin value of 11.0 g/ dl, about 13% of outpatients who came to our Geriatrics department were found to have anemia, and in most of them the anemia had resulted from another disease. In conclusion, anemia in the elderly is likely to be affected by reduction in the function of various organs and by the decreased reserves associated with aging. The causes of anemia are complex and diagnosis is often difficult. The present article gives a general outline of the diagnosis and treatment of common types of primary and secondary anemia in the elderly.