Early menopause no predictor of hip fracture

Women who have an early menopause are unlikely to have a long term increased risk of hip fractures associated with menopausal bone density weakening, according to a new study from the Australian National University.

For decades medical practitioners have understood a link between menopause and a decrease in bone density. This has translated into clinicians advising women who had an early menopause that they are at particularly high risk of hip fracture – a common complaint amongst the elderly.

The study, led by Associate Professor Emily Banks of the National Centre for Epidemiology and Population Health at ANU, has found that age is the main determinant of hip fracture and that among the elderly their age at menopause has little, if any, effect on hip fracture risk. Hence, doctors should base their advice on the age of patients alone.

The researchers used data from the UK's Million Women Study to reach their findings. The Million Women Study recruited 1.3 million women aged 50–64 years who attended breast cancer screening clinics between 1996 and 2001 to investigate how reproductive and lifestyle factors affect women's health.

"The findings show that among post-menopausal women, age is the major determinant of hip fracture risk and that for women of a given age, their age at menopause has little effect on hip fracture risk," said Dr Banks.

"The results suggest that clinicians advising women about hip fracture prevention should probably base their advice on the woman's age and on age-related factors such as frailty, rather than on factors related to menopause. Clinicians can also now reassure elderly women who had early menopause that their risk of hip fracture is unlikely to be higher than that of similar women who had a later menopause," she said.

Hip fractures are a serious problem for elderly people, especially women. As people age, their bones gradually lose minerals and become less dense, which makes them more susceptible to fracture. Because women lose bone density faster than men as they age and because women constitute the majority of the elderly, three-quarters of hip fractures occur in women.

"Although surgical repair of a broken hip only requires a hospital stay of about a week, a quarter of elderly people who were living independently before their fracture have to stay in a nursing home for at least a year after their injury, and a fifth of elderly people who break a hip die within a year," said Dr Banks.

The study has been published in Public Library of Science Medicine.

(Source: Australian National University: Public Library of Science Medicine: November 2009)