London - Women taking HRT could cut their risk of heart disease and an early death – as long as they start in their 50s, according to researchers.
Data from 40,000 patients found that those taking the drugs from this age were less likely to die prematurely from any cause and the threat of heart attack was halved.
However, the likelihood of blood clots was slightly raised among women who begin Hormone Replacement Therapy in their 50s, which is normal practice.
But when evidence from women across a wider age range was examined, it showed oral HRT did not protect against heart disease and may increase stroke risk.
HRT is given to control symptoms of the menopause but this large-scale review sought to investigate if it has positive or negative effects on other areas of health.
Around 9,000 women formed the sub-group who were given the treatment at, or not long after, the menopause and before 60. They took it for three to ten years.
Lead researcher Dr Henry Boardman, from Oxford University, said: ‘The evidence we have provides some support for the so-called “timing hypothesis” but we should bear in mind the size of this effect.
‘When we looked at the results according to the age of women, or by how long since their menopause that they started treatment, we found that if 1,000 women under 60 started therapy we would expect six fewer deaths, eight fewer cases of heart disease and five extra blood clots over about seven years, compared to a 1,000 similar women who did not start.’
An estimated one million women in the UK take HRT for symptoms like hot flushes and mood changes although it also protects bones.
However, some specialists have long held that HRT should prevent heart disease based on the fact that when women naturally lose supplies of oestrogen at the menopause, their heart risks rise. The theory was that taking oestrogen supplements – the basis of HRT – would help restore protection. But startling results from the US Women’s Health Initiative study in 2002 not only found no heart disease benefits but harm caused by breast cancer. However, expert analysis has since concluded that the risks were largely found in women taking HRT many years past the menopause in their 60s and 70s for whom it was never intended.
The latest findings, published in the Cochrane Library international database, came to a similar conclusion.
In women under 60 or who started HRT within ten years of the menopause, there was a 30 per cent drop in deaths from any cause and a 48 per cent lower risk of coronary heart disease.
As well as a small increased risk of blood clots, there was a suggestion of a higher chance of stroke. However, this was inconclusive.
The general findings across different age groups showed death rates from any cause, specifically cardiovascular disease, were not affected by being on HRT. But there was a 24 per cent higher risk of stroke.
Dr Boardman said: ‘The evidence adds to a large bank of evidence that helps GPs advise their patients. But you need to weigh up the severity of the symptoms and the benefits and harms.’
Dr David Tovey, editor-in-chief of the Cochrane Library, said: ‘The main analysis that the authors did found no benefit and so we need to apply caution to the results from the sub-group analysis.
‘However if true, this apparent benefit in preventing heart disease in younger women should be considered alongside other possible benefits and emerging evidence of harms, including the risk of breast cancer, ovarian cancer and DVT.’
The review looked at almost 4,000 investigations worldwide, including two large American studies which recruited women as old as 79.
Daily Mail