Benefits from short-term hormone therapy are likely to outweigh the risks

Aug 13 2004

A group of prominent experts on treatment of the menopause today issued advice for doctors on the use of hormone therapy.

Under the auspices of the Royal Australian and New Zealand College of Obstetricians and Gynaecologists (RANZCOG), the group of more than 20 experts declared that the benefits of short-term hormone therapy are likely to outweigh the risks for otherwise healthy women with moderate to severe symptoms.

The group has estimated the increased risk for major reported side-effects, using known disease rates for Australian women and the best available data from overseas studies on hormone therapy.

The experts said the increased risk of breast cancer from combined oestrogen-progestin therapy might result in about an extra eight cases per 10,000 women per year among 50 to 79-year-olds. The normal risk among women aged 50-59 is about 27 cases per 10,000 women per year. The increase in risk appears to be associated with duration of treatment, with the increase becoming evident after treatment for four years in one major study. The only major randomised trial of oestrogen-only therapy showed no increase in risk of breast cancer after nearly seven years in hysterectomised women.

The experts concluded that there was insufficient evidence on the effects of hormone therapy on heart disease in the early post-menopausal years. They said hormone therapy should not be used for treatment or prevention of heart disease. Taking into account older age groups in US studies, hormone therapy could be associated with a risk increase of approximately 7 cases per 10,000 women per year for women aged 50 to 79. The normal risk is about 39 cases per 10,000 women per year for women aged 45 to 54.

The experts met for two days last week following widespread concerns and confusion among doctors and patients in the past two years. Prescription rates for hormone therapy have declined significantly since the abandonment of a large American trial, the Women’s Health Initiative (WHI), due to a reported increase of rates of heart disease, strokes and breast cancer. The experts reviewed the data from the WHI and dozens of other hormone therapy research papers. Experts noted problems with the initial conclusions reached from the WHI data due to the relatively high average age and therefore risks of the trial subjects and other issues.

A key message from the experts was that all women on hormone therapy should have a review with their doctors at least once a year to determine whether they should continue using HT, based on their individual need.

The president of RANZCOG, Dr Andrew Child, said: “Many women suffer from intolerable symptoms around the menopause and find that hormone therapy brings remarkable improvement to their problems. They need to be given clear guidance by their GP as to the benefits and risks of such therapy.”

Dr James Brodribb, chair of the Women’s Health Committee of the RANZCOG, said this was the first time that such a large multi-disciplinary group of experts had formulated straightforward evidence-based hormone therapy advice for Australian doctors. Dr Brodribb said: “We believe it is a simple guide to the evidence as it now stands. This is what doctors and patients have been looking for. This provides greater clarity and reassurance for doctors for discussion with the large numbers of otherwise-healthy women who have distressing symptoms of the menopause. There are some risks, but these have been identified and put in context.”

Another key driver of the conference, the president of the Australasian Menopause Society, Professor Susan Davis, said: “Some doctors have become so uncertain of the use of hormone therapy that they are unwilling to prescribe hormone therapy for severely symptomatic women. Clear recommendations that represent the major health disciplines, as to what is good medical practice in this field, were greatly needed.”

Among the other experts contributing to the advice were representatives from the Endocrine Society of Australia, the Royal Australian and New Zealand College of Psychiatrists, the Menzies Research Institute, Osteoporosis Australia and the Menopause Centre at the University of Adelaide. About 35 experts attended all or part of the conference.

On stroke, the experts said this was uncommon in women aged 45 to 54, with the incidence about 7 to 8 strokes per 10,000 women per year. This rose to 26 per 10,000 women per year among women aged 55 to 64. The use of hormone therapy may increase the risk of stroke among 50 to 79-year-olds by 8 to 12 strokes per 10,000 women per year.

On dementia, the experts said there was insufficient evidence to say that hormone therapy increased or decreased the risk, but it should not be used for prevention of dementia. They said hormone therapy reduces the risk of fragility fractures and HT may be an option for reducing fracture risk when first-line therapies were not appropriate in individual cases.

On ovarian cancer, they said some studies suggested a possible increase with hormone therapy, but there was insufficient evidence to draw conclusions.

On venous thromboembolic events, including blood clots, the experts said the general risk increases substantially with age in healthy women. The baseline risk for women in their 50s is 1 in 10,000 per year, increasing to 100 per 10,000 per year for women in their 80s. The use of oral hormone therapy doubles this risk.

The lowest effective dose should be used, even though there was a lack of quality evidence on this issue. Some women may require long-term therapy for symptom control. They said there was no evidence on which to advise on complementary or so-called natural therapies. And there was no evidence for the safety of unregistered medicines described as ‘bioidentical’ or compounded therapies.

http://www.ranzcog.edu.au