8 October, 2012:
The preliminary results of the Kronos Early Estrogen Prevention Study (KEEPS) were presented at the NAMS meeting last week and immediately brought to the public attention through the media. KEEPS was a 4-year randomized, double-blinded, placebo-controlled clinical trial of low-dose oral or transdermal (skin patch) estrogen and cyclic monthly progesterone in healthy women aged 42–58 years (mean age 52 years) who were within 3 years after menopause at randomization. A total of 727 women were randomized into the following three arms, along with cyclical micronized progesterone (Prometrium®): oral arm, conjugated equine estrogen (CEE) given as Premarin®, 0.45 mg/day (a lower dose than the 0.625 mg/day used in the Women's Health Initiative (WHI) trial); transdermal arm, estradiol given by Climara® patch, 50 μg/day; and a placebo arm.
Improvements in hot flushes, night sweats, mood, sexual function, and bone density were observed with hormone therapy (HT) vs. placebo. Oral CEE, but not transdermal estradiol, was associated with an increase in HDL cholesterol. The oral CEE group had a decrease in LDL cholesterol, but also an increase in triglyceride levels. Transdermal estradiol had neutral effects on these biomarkers. Transdermal estradiol appeared to improve insulin sensitivity, calculated from glucose and insulin levels as HOMA-IR. Neither oral CEE nor transdermal estradiol significantly affected systolic or diastolic blood pressure, in contrast to the higher dose of CEE in the WHI, which increased blood pressure levels. During 48 months of treatment with either type of HT vs. placebo, there were no apparent effects, either beneficial or deleterious, on atherosclerosis progression assessed by carotid ultrasound and a non-significant trend toward less accumulation of coronary artery calcium. No significant differences in adverse events (breast cancer, endometrial cancer, myocardial infarction, transient ischemic attack, stroke, or venous thromboembolic disease) were found among groups. However, the absolute numbers of such events were extremely small in all three treatment groups, making definitive conclusions impossible.
In conclusion, KEEPS found many favorable effects of HT in newly menopausal women. The results provide reassurance for women who are recently menopausal and taking HT for short-term treatment of menopausal symptoms. KEEPS also highlights the need for individualized decision-making about HT, given that oral CEE and transdermal estradiol may have different profiles of effects and different women have different symptom profiles and priorities for treatment.