Healthy women facing menopause should seriously consider the consequences of taking hormone replacement therapy (HRT). One major study was stopped in 2002 after women randomly assigned HRT were found to be at greater risk of developing cancer and cardiovascular disease than the women in the control group taking only a placebo.

Follow-up studies five years later seem to indicate the cancer risk remains high for those on HRT as opposed to those who were not.

Researchers at the University of North Carolina, Chapel Hill, (UNC) have just announced the findings from a follow-up study of participants of the Women’s Health Initiative (WHI). In the original trial, 16,608 healthy postmenopausal women were randomly assigned to a group receiving HRT that involved a combination medication which included both estrogen and progestin or to a control group that received placebo medications instead.

The object of the study was to determine the value of HRT in the prevention and treatment of bone fractures, cancer, and cardiovascular disease in postmenopausal women.

In the original study, women in the HRT group developed an increased risk of cardiovascular disease and breast cancer. The study was stopped in July 2002, when women of the HRT group had been in the study an average of 5.6 years.

In follow-up examinations of 15,730 participants, spanning the period of July 2002 to March 2005, the increased risk of some cancers remained higher for the HRT group than the placebo group. Even though the risk remains higher, it has dropped slightly since the HRT was stopped.

The risk of colorectal cancer didn’t vary much between the two groups during follow-up, nor did the risk of bone fractures. And the HRT group actually enjoyed lower rates of endometrial cancer. The one-time elevated risk of cardiovascular disease diminished over time after the HRT was stopped, too.

The follow-up study confirms the original trial’s main conclusion – HRT is ineffective in reducing the risk of certain diseases in postmenopausal women who are otherwise healthy. Instead, women should make healthy lifestyle choices that include minimizing risk factors and getting regular medical check-ups.

The full report of the study, by lead author Dr. Gerardo Heiss, epidemiology professor at UNC’s School of Public Health, has just been published in the Journal of the American Medical Association (JAMA).

Source: University of North Carolina at Chapel Hill

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