Much debate and controversy surrounds the issue of risks and benefits of Hormone Replacement Therapy (HRT). In the past, many women took HRT in the belief that, while accepting that all medicines, and indeed many non-medicines, carry some risk, overall for most women the benefits appeared to outweigh the risks. All this changed in 2002 when a large American trial, the Women's health Initiative trial, (WHI) showed that the use of HRT increased the risks of breast cancer, heart disease, stroke and blood clot. Following swiftly on came the British Million Women study which emphasisied the risks of breast cancer with HRT. Understandably, women in their millions stopped taking HRT and many doctors stopped prescribing it.
Were these concerns and huge change in use of HRT justified?
The WHI trial has since been reanalysed and in fact, heart disease and stroke were only increased in women who were 20 or 10 years post menopause respectively and were starting HRT just for the purpose of the trial. Women in the trial taking HRT who were under the age of 60 were shown to have a reduced risk of heart disease. A small increased risk of blood clot is found in women taking tablet form of HRT in the first year of use, but not if taking transdermal (patch or gel). The risk of breast cancer in WHI was in fact NOT demonsrtated in women taking estrogen only HRT, and in women taking combined estrogen and progestogen HRT, was only increased if HRT was taken before the trial and then continued for the 5 years of the trial. The level of increased risk shown is less than the associated breast cancer risk with 2 or more units of alcohol per day, or with being overweight after the menopause.
Further, a recent publication has shown that the Million Women study was in fact flawed and did not prove an increased breast cancer risk with HRT.
So where are we now? A very comprehensive review of the facts has now been published in the British Medical Journal and shows that we have almost come a whole circle, in that we have conclusive evidence that HRT is still the most effective treatment for menopausal symptoms, reduces the risk of osteoporotic fracture, reduces the risk of diabetes and colon cancer and, if used early in the menopausal years may well reduce the risk of heart disease. The association with long term use of HRT after the age of 50 and breast cancer risk is of concern but all medicines carry some risk and it seems once again, that overall for most women the benefits appeared to outweigh the risks.