New HRT study sheds light on risks, benefits of treatment
New research involving the University of Adelaide has confirmed that women aged 65 and over should not start hormone replacement therapy (HRT) as a possible prevention for heart disease and other conditions.
The latest findings of the WISDOM research team (Women's International Study of long Duration Oestrogen after Menopause) have been published on the international medical journal website www.bmj.com.
The results show that older women who were not already on HRT are not likely to gain any health benefits from taking it - instead, there might be increased risks of cardiovascular and other serious conditions if they start taking HRT for the first time.
The international research team - led in Australia by Professor Alastair MacLennan from the University of Adelaide's Discipline of Obstetrics & Gynaecology - studied more than 5600 women in the UK, Australia and New Zealand from 1999 to 2002 in the hopes of assessing the long-term effects of HRT.
That study was cut short in 2002 when another study found that elderly post-menopausal women taking HRT had more heart attacks and strokes than non-HRT users. As a result, millions of women around the world stopped taking HRT.
However, the WISDOM team's findings and those from recent trials suggest that these risks only apply to older women who have established heart disease, Professor MacLennan said.
"Our findings support the view that HRT is a safe treatment for younger women in early menopause to relieve symptoms and improve quality of life," he said.
"Women commencing HRT under age 60 have a reduction in heart disease because oestrogen prevents thickening and hardening of the coronary arteries, but cannot reverse this once arterial disease is established after about age 65.
"Based on our studies, HRT only has adverse effects for women over 65 who are taking HRT for the first time."
The 5600 women studied by the WISDOM team were monitored for an average of 12 months and main outcomes such as cardiovascular disease, osteoporotic fractures, breast cancer and deaths were recorded.
The results show that there was a significant increase in the number of major cardiovascular events (angina, heart attack or sudden coronary death) and blood clots in those taking combined hormone therapy (oestrogen and progestogen) compared with the placebo group. Rates for cerebrovascular disease, breast or other cancers, and overall deaths, were not significantly different in these two groups.
"The study confirms an early increase in blood clots and cardiovascular risk in older women starting hormone replacement therapy on average 15 years after menopause," Professor MacLennan said.
"However, these results cannot necessarily be applied to younger menopausal women starting HRT to relieve symptoms such as hot flushes and night sweats. For these women, recent studies suggest there are cardiovascular benefits of taking HRT around the time of menopause.
"More research is needed to assess conclusively the long-term benefits and risks among these women," he said.
Story by David Ellis
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