AN INAPPROPRIATE ERYTHROPOIETIC RESPONSE TO IRON-DEFICIENCY ANEMIA INTHE ELDERLY

This study was carried out to clarify the features of iron deficiency anaemia in the elderly. Subjects were chosen from residents undergoing an annual health check in a home for the aged and the features of ana emia in the elderly were compared with those in middle-aged adults und er 60 years old, The red cell count, red cell size and haemoglobin con tent in an elderly group with iron-deficiency anaemia did not differ f rom those in middle-aged adults. No significant differences of the ser um ferritin and iron levels were noted between the two groups. Total i ron binding capacity was higher in the middle-aged adults than in the elderly, while the reticulocyte count was significantly lower in the e lderly group. Immature reticulocytes showing a considerable amount of residual RNA by now cytometry with fluorescent staining were also lowe r in the elderly group than in the middle-aged adults. Serum erythropo ietin levels in both groups were significantly higher than in non-anae mic age-matched controls,and no difference in erythropoietin levels wa s noted between them. The ratio of the reticulocyte count to the log-t ransformed erythropoietin level was low in the elderly group with iron -deficiency anaemia compared with the middle-aged adults with iron def iciency anaemia. The same result was seen when the immature reticulocy te count was related to the log-transformed erythropoietin level. Thes e findings suggest that the red cell production response to erythropoi etin in the elderly with iron-deficiency anaemia might be inappropriat e compared with both non-anaemic and anaemic middle-aged adults.