The decrease in bone density that accompanies aging is only a small factor in the greatly increased risk of hip fracture in older life, researchers have discovered.

This finding calls into question one of the supposed greatest benefits of HRT, whose proponents claim it offers protection against osteoporosis, which is a progressive deterioration of bone density.

Doctors had always assumed that bone density which usually starts to decline in women after the menopause was associated with the risk of fractures, which increases exponentially among the elderly.

But researchers from the Erasmus University Medical School in Rotterdam found that, while the risk of hip fracture increased 13 fold in both men and women aged between 60 and 80, bone density levels played a minor part in increasing the risk.

The researchers also found that the risk of hip fracture was as great among men as women, whereas it had been believed that women were at greater risk (BMJ, 1997; 315: 221-5).

Another alleged benefit of HRT that it protects against heart disease has also been refuted by a team of researchers in the biggest study to date of HRT's effect on the heart.

They studied 22 trials, involving 4124 women, and found there was very little difference in the rate of heart disease between those women taking HRT and those who were not. The analysis was carried out by the National Research and Development Centre for Welfare and Health in Helsinki, Finland (BMJ, 1997; 315: 149-53).

For more information on HRT see WDDTY vol 6 nos 10 and 12, vol 5 nos 4 and 12 and WDDTY's Guide to the Menopause.