Making a decision about ERT/HRT. Evidence to consider in initiating and continuing protective therapy

Alzheimer's disease, CAD, and osteoporosis significantly affect the health and well-being of senior citizens in the United States. The fact that women have a longer life expectancy than men has led to the hypothesis that estrogen in some way imparts protection against these disease processes. Available data on the possible negative effect of estrogen on the development and progression of Alzheimer's disease are provocative but inconclusive. Thus, for the time being, they must remain no more than the basis of an attractive hypothesis. In contrast, available data suggest that ERT and HRT can reduce the risk of CAD, but this effect seems more preventive than therapeutic. Addition of a progestational agent to an estrogen regimen may blunt this effect. Although the medical literature contains very few data that address the issue of duration of therapy, logic would suggest that cessation of therapy would result in the loss of a protective effect. With regard to osteoporosis, ERT and HRT have clear beneficial effects in that they increase BMD and decrease fracture risk. There is good evidence that duration of therapy may be more important than dosage and that these effects rapidly dissipate with cessation of therapy. Finally, as with all medical interventions, ERT or HRT must be individualized for each patient. Although actual health hazards are few, adverse effects are common and the emotion-charged, ever-evolving issue of the negative impact of ERT and HRT on breast cancer risk must always be considered before such therapy is instituted.