The risk of advanced breast cancer is significantly increased by hormone replacement therapy, a US study has shown.
The Women's Health Initiative (WHI) found that the use of oestrogen plus progestin hormone therapy is linked to aggressive forms of breast cancer.
The findings showed that death rates of the disease doubled in a group of women who underwent HRT for an average of 5.6 years.
The WHI had previously demonstrated the link between HRT and breast cancer in post-menopausal women, but the new study shows that HRT is also linked to a higher risk of death caused by the disease.
Nearly 13,000 women took part in the study, and were either given combination HRT or a placebo pill.
Their health was then monitored for 11 years after treatment.
Of those who received the hormone treatment, 385 developed invasive breast cancer, compared with 293 who received the placebo.
Breast cancers, which spread to the lymph glands, were detected in a significantly larger percentage of those who received HRT.
There were 25 deaths from breast cancer among the HRT group and 12 among the placebo group. At a population level, this was the equivalent of 2.6, compared with 1.3 deaths per 10,000 women per year.
The findings were reported in the latest issue of the Journal of the American Medical Association.
Copyright © Press Association 2010
Women's Health Initiative
You are currently leaving the Nursing in Practice site. Are you sure you want to proceed?