Hormone Replacement Therapy

[Note: hormone therapy (HT) may also be referred to as hormone replacement therapy (HRT).]

Media Release from Therapeutic Goods Administration - August 7, 2003

In 2002, the US Women's Health Initiative (WHI) Study released important information about the long-term safety of oestrogen plus progestin combination hormone replacement therapy (HRT). In a trial enrolling more than 16,000 postmenopausal women, they reported a small but important increase in the incidence of heart attacks, stroke, clotting events and breast cancer. This information has been strengthened by the publication of the UK Million Women Study that examined the effect of HRT on the development and outcomes of breast cancer.

Shortly after publication of this study, an Australian expert committee was convened under the auspices of the Chair of the Australian Drug Evaluation Committee, Professor Martin Tattersall.

The committee's major recommendation was that combination HRT should not be used for long-term disease prevention, but that short-term HRT use is still an appropriate treatment option for the treatment of symptoms of menopause.

Further information available from the WHI study came from an analysis of women 65 years of age and over. These results found that the incidence of dementia in women receiving HRT was statistically significantly higher than those receiving placebo tablets. According to the study, an additional 23 per 10,000 women (from 22 to 45) developed signs of dementia in association with long term HRT use.

The latest information available on the issue of breast cancer risk comes from the UK Million Women Study. This study looked specifically at breast cancer and it confirmed that women on HRT have an observed higher incidence of breast cancer and a tendency to worse outcomes. New information suggested a higher mortality from breast cancer by 4-5 years for combined HRT but elevations in risk were also seen in women who received oestrogen-only HRT and tibolone (synthetic HRT).

Professor Tattersall said today "This new information supports the expert committee's previous recommendations that combination HRT should not be used for long-term disease prevention."

"This follows a report published in the New England Journal of Medicine on 8 May 2003, in which it was reported that the combination HRT users from the WHI study also had no quality of life benefit compared to the control women, as measured by 12 aspects including energy, sleep and mood."

Content updated August 18, 2003