to the editor: I found Dr. Havranek's article¹ to be a helpful overview of coronary heart disease (CHD) prevention. However, I am concerned with his conclusion that hormone replacement therapy (HRT) is unlikely to be a beneficial primary prevention strategy for CHD in women.

Dr. Havranek erroneously bases his conclusion on the findings of the Heart and Estrogen/progestin Replacement Study (HERS).² HERS is very specific: the study investigates the effects of HRT on recurrent coronary events in women with known CHD who received a regimen of conjugated equine estrogen (0.625 mg daily dosage) plus medroxyprogesterone acetate (2.5 mg daily dosage). HERS found an increase in CHD events in the hormone-treated group in year 1 of the study and a decrease in CHD events in years 4 and 5. The treatment conclusion was that HRT should not be initiated for secondary CHD prevention, but women already taking HRT should probably continue therapy because of the potential for longer-term benefits in CHD prevention.

Previous studies have shown the benefits of HRT in the prevention of CHD. The National Cholesterol Education Program's adult treatment panel II recommended estrogen therapy for all women with hypercholesterolemia in whom estrogen is not contraindicated.³ Multiple observational studies have shown a consistent decrease in CHD risk among post-menopausal women who take HRT.^4,5 The AAFP's monograph on heart disease in women states, “recent research suggests that the use of estrogen or hormone replacement therapies for postmenopausal women can substantially decrease the risk of cardiovascular disease.”⁶ Furthermore, it states that, “HRT has been identified as the most significant factor in the effort to reduce the risk of cardiovascular disease for postmenopausal women.”⁶

The final word has certainly not been written on HRT and heart disease. Family physicians need to be aware of ongoing research in order to provide the best opportunity for patients to make informed decisions about HRT.

in reply: Dr. Elliott takes issue with the statement in my article¹ that hormone replacement therapy (HRT) in postmenopausal women is unlikely to be of benefit as primary prevention for coronary heart disease (CHD). She bases her disagreement on the recommendations of two expert panels published before the results of the Heart and Estrogen/progestin Replacement Study (HERS),² on the fact that the HERS trial was a secondary prevention trial and on the results of observational studies.

It is not at all clear that the cited expert panels would not be more cautious now that HERS has been reported. With regard to the issue of secondary prevention, my article makes it quite clear that HERS was a secondary prevention trial. It is no more erroneous to base recommendations on the basis of secondary prevention trials than it is to base recommendations on the basis of observational studies. In discussing HRT as primary prevention, I made a conscious decision to put more weight on the results of a secondary prevention trial than on the results of observational studies. The article contains several precedents that support such a decision. With cholesterol reduction, secondary prevention trials showed benefit before primary prevention trials. With vitamin E supplementation, observational studies suggested benefit; a randomized primary prevention trial did not.

Dr. Elliott and I agree that no definitive data on the efficacy of HRT for primary prevention of CHD are available. In the absence of definitive data, physicians and patients must make the best use of all available information and support ongoing efforts to arrive at an answer to this important question.