The effect of combined hormone replacement therapy (HRT) in increasing a woman’s risk of breast cancer is likely to have been underestimated by a number of previous studies, according to a new prospective study published in the British Journal of Cancer.
HRT is used to treat uncomfortable symptoms of the menopause by topping up the decreased levels of oestrogen being produced by the body.
Researchers followed more than 100,000 women for 40 years to investigate the causes of breast cancer. Some 39,000 women with a known age at menopause were identified and monitored for six years, with follow-up questionnaires gathering comprehensive data on any HRT use (type and duration) as well as their general health and lifestyle.
During this time, 775 of these women developed breast cancer, with the researchers finding that women using combined HRT (for a median duration of 5.4 years) were 2.7 times more likely to develop breast cancer during the period of HRT use than women who had never used HRT.
This risk increased with duration of use, with women who had used combined HRT for over 15 years being 3.3 times more likely to develop breast cancer than non-users. However in women using oestrogen-only HRT there was no overall increase seen in breast cancer risk compared with women who had never used HRT. Importantly, this increased risk level has been found to return to about normal once HRT use ends.
Study leader Professor Anthony Swerdlow, Professor of Epidemiology at the ICR said: “Our research shows that some previous studies are likely to have underestimated the risk of breast cancer with combined oestrogen-progestogen HRT. We found that current use of combined HRT increases the risk of breast cancer by up to three fold, depending on how long HRT has been used.
Responding to the findings, natural health practitioners have urged for a stronger focus on herbal approaches for managing menopause symptoms. Herbalist Dee Atkinson said: “… It’s time to take a reality check. The Menopause is normal and natural and we need to ask ourselves if we’ve always had such awful symptoms and if this really has, historically, been part of the aging package? I would say the answer is “No”. We have made the situation worse with lifestyle choices, stress, diet issues and, probably, with using hormone altering drugs, such as the pill, in the past. I think it is time to look again at all the plant based solutions to menopause.”
