Hematopoiesis in the elderly.

The effect of age on the hematopoietic system has always been an area of clinical interest. Alterations in lymphocyte immunophenotype and function with age have been clearly demonstrated as has a decrease in neutrophil function. However, controversy continues to surround the significance of unexplained anaemia in the elderly patient and the extent to which this could be a physiological occurrence. The weight of evidence from animal and human studies would suggest that anaemia is not a physiological occurrence but may have a multifactorial pathogenesis. Are older patients therefore, appropriate candidates for high dose therapy, including autologous stem cell transplantation? The loss of telomeric DNA from hematopoietic progenitor cells with aging implies that stem cell collections from an older patient may have compromised replicative capacity with a reduced response to hematopoietic growth factors. Recent studies, however, show that age is not an obstacle for the collection of a stem cell product, which is capable of restoring normal hematopoietic function. A study of autologous stem cell transplantation has shown comparable neutrophil and platelet recovery times between younger and older patients. Copyright 2004 Taylor and Francis Ltd