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HRT risks outweigh benefit according to 13 year follow up of WHI


The health risks associated with long-term HRT outweigh the benefits, according to the authors of the extended follow-up analysis of the Women's Health Initiative (WHI) trials published in this week’s issue of JAMA.

But HRT may be appropriate for management of menopause symptoms in some women, they conclude.

The two WHI trials started in 1993 and involved 27,347 postmenopausal US women aged 50 to 79 years. Those with intact uteri received conjugated equine oestrogens (CEE) plus medroxyprogesterone acetate (MPA) or placebo. Women who had had hysterectomies received CEE alone or placebo.

Findings in the latest paper – described as a “comprehensive, integrated overview" of original findings of the trials and a cumulative 13 years of follow-up – include:

  • Women in the CEE+MPA group were 80% more likely to develop coronary heart disease while they were on treatment than women receiving placebo. Those on CEE-alone had no significant increase in CHD. The increased risk seen in the CEE + MPA group was not sustained post-treatment.
  • Women in the CEE+MPA group were 24% more likely to develop breast cancer than women in the placebo group. But women in the CEE-alone group had a non-significant 21% reduction in risk. The elevated risk remained significant for the CEE+MPA women after treatment  whereas the risk reduction for CEE women remained at 21% but became statistically significant during follow-up.
  • Stroke risk increased by 37% in both groups during the intervention but disappeared after treatment.