Herrington D M
Department of Internal Medicine/Cardiology, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157-1045, USA.
Ann Intern Med. 1999 Sep 21;131(6):463-6. doi: 10.7326/0003-4819-131-6-199909210-00012.
The Heart and Estrogen/progestin Replacement Study (HERS) found no overall effect of 4.1 years of therapy with estrogen plus progestin for secondary prevention of coronary heart disease in postmenopausal women. However, within the overall null effect, a 50% increase in cardiovascular events was seen in the first year, followed by fewer events after 2 years of treatment in the hormone therapy group than in the placebo group. Understanding the cause of this pattern of early increase and late reduction in risk is key to interpreting the HERS results and reconciling them with the large number of observational and other studies of the cardiovascular effects of estrogen. There are two possibilities. One is that the HERS regimen of estrogen plus progestin has no effect on risk for heart disease, and the pattern of changing risk over time is simply the result of chance or confounding. The other is that the pattern of early increase and late reduction in risk is due to real but opposing effects of this regimen. Several lines of evidence support each possibility. Attrition of a susceptible cohort of women uniquely at risk for a cardiovascular complication from hormone therapy coupled with a gradually progressive beneficial effect due to lipid lowering and other factors is a promising potential explanation. The HERS results remind us of the need for clinical trials to evaluate both the benefits and risks of new therapies. They also illustrate how much more we need to know about the cardiovascular effects of hormone replacement therapy.
心脏与雌激素/孕激素替代研究（HERS）发现，对于绝经后女性冠心病的二级预防，采用雌激素加孕激素进行4.1年的治疗并无总体效果。然而，在总体无效的情况下，激素治疗组在第一年心血管事件增加了50%，而在治疗2年后，该组的事件少于安慰剂组。了解这种风险早期增加和后期降低模式的原因，是解读HERS研究结果并使其与大量关于雌激素心血管效应的观察性研究及其他研究结果相协调的关键。有两种可能性。一种是HERS研究中雌激素加孕激素的治疗方案对心脏病风险没有影响，风险随时间变化的模式仅仅是偶然或混杂因素的结果。另一种是风险早期增加和后期降低的模式是由于该治疗方案存在真实但相反的效应。有几条证据支持每种可能性。因激素治疗而有独特心血管并发症风险的易感女性队列的流失，再加上由于降脂和其他因素逐渐产生的有益效果，是一个有前景的潜在解释。HERS研究结果提醒我们需要进行临床试验来评估新疗法的益处和风险。它们还表明我们对激素替代疗法的心血管效应还有多少需要了解。
