Medical Matters: With so much emphasis on the prevention of health problems, it is easy to be overwhelmed by advice. So it is especially helpful when good quality research on preventive medicine is published.
Last week both the British Medical Journal and the Lancet had two significant papers on different health issues affecting women aged 50 and over.
The first was a report from the Million Women Study, a major piece of research from the University of Oxford. Some 717,000 postmenopausal women aged 50-64 years were enrolled in the study between 1996 and 2001. They were questioned about the use of hormone replacement therapy (HRT) - just under half reported they had used some form of HRT. All still had their wombs and none of the women had a history of cancer.
After a follow-up of three and a half years, 1,320 womb cancers were diagnosed in the group. The researchers discovered that, compared with women who had never used HRT, those who used oestrogen-only preparations or a drug called Tibolone had a higher risk of womb cancer. In addition, the risk of cancer increased the longer Tibolone was used. The good news was that using combined HRT (oestrogen and progesterone) did not increase the incidence of cancer of the uterus.
Interestingly, women who were clinically obese, who ordinarily have a substantially higher risk of womb cancer, had this risk reduced if they had taken either cyclic or continuous combined HRT.
Previous data from the Million Women Study found that taking combined preparations of HRT increased a woman's risk of breast cancer.
So what does all this mean for a woman facing into the menopause?
If you have had a hysterectomy, then oestrogen-only HRT does not pose an additional risk of either breast or womb cancer. But it creates something of a dilemma for the majority who still have their wombs. Both oestrogen-only HRT and Tibilone increase the risk of cancer of the uterus. Combined HRT increases the risk of breast cancer. And since breast cancer is much more common than womb cancer, using combined HRT poses the greatest overall cancer risk.
When the risks of increased heart disease from prolonged HRT are taken into account, it appears that women should only take HRT for short periods and in a form that contains the lowest possible dose of oestrogen.
While this will undoubtedly help combat menopausal symptoms in the short term, it means there are no easy solutions to symptom relief and disease prevention as the menopause progresses.
One of the greatest hopes 10 years ago was that HRT would help prevent osteoporosis in women. In fact, the synthetic steroid Tibilone was seen as especially useful in this regard. However, this latest research linking it to an increased risk of womb cancer has dented these hopes.
Osteoporosis affects one in three women over the age of 50. It is one of the biggest risk factors for fractures of the hip which are particularly debilitating and associated with premature death. Fractures of the spine cause pain, deformity and loss of physical activity.
The paper from the British Medical Journal looked at the effects of taking calcium and vitamin D supplements on the prevention of fractures in older women.
This study was important because it took place in the community and so is especially relevant to the majority of women. The researchers identified 3,314 women aged 70 and over who were considered to be at high risk of hip fracture. The women were randomly split into two groups.
The treatment group received advice from a practice nurse on how to reduce the risk of fracture and they were also given calcium and vitamin D tablets to take daily. The control group received only a leaflet containing dietary advice and information on how to prevent falls. All women were monitored for an average of two years.
The researchers from the University of York and the Freeman Hospital, Newcastle found no evidence that calcium and vitamin D supplements reduced the risk of clinical fractures in women with known risk factors for the disease.
These risk factors included low body weight, being a smoker, and having either a family history of hip fracture or personal experience of any fracture. The group given supplements were prescribed 1,000mg of calcium and 800 IU of cholecalciferol (vitamin D).
This is the first ever randomised study carried out to measure the effects of supplements among women at high risk of osteoporosis living in the community. It is somewhat weakened by the fact that compliance with treatment was just over 60 per cent. Nevertheless, it suggests that women over 70 may gain as much benefit from a good diet as from specific treatment with calcium and Vitamin D.
For a free information booklet, Don't let your bones reach breaking point, tel: 1850 924885 or log onto www.breakingpoint.ie
Dr Muiris Houston is pleased to hear from readers at mhouston@irishtimes.ie but regrets he cannot answer individual queries.