Most fractures of the hip, arms, legs, arms and spine in elderly people are associated with osteoporosis. This is a common condition in older women, but it can also occur in men as they age.

The bone structure becomes less dense, and therefore much more fragile. Professor Prince, from the University of Western Australia, has reviewed the ways in which it is possible to predict which patients with osteoporosis are at the greatest risk of suffering a fracture. Such information is valuable, as it can help physicians decide on the intensity of preventive treatment required. For instance, if the risk of fracture over a 5-year period is less than 5%, only minimal intervention should be considered; very high risk (i.e. above 20%) demands the use of vigorous treatment steps.

There are 5 main factors which affect the risk of fracture in patients with osteoporosis: life expectancy, age, bone density, previous fracture history, and the underlying condition responsible for the osteoporosis (if known).

If life expectancy is relatively short – just a few years, for one reason or another – there would have to be a very high risk of fracture to justify intervention to prevent fractures. For instance, there are specific treatments that may be helpful in reducing fractures in advanced breast cancer. In other life-shortening conditions, such as heart failure, there is little need to treat an accompanying osteoporosis.

Increasing age affects the fracture rate in men and women. After 65, the risk of fracture in women with osteoporosis rises from a 5% risk to a 30% risk at the age of 90. In men, a 5% risk at 70 also rises, peaking above 10% at 90 years. So all 80-year-olds should be considered for treatment of osteoporosis, even if only by calcium supplements.

Bone density determination is a fairly common procedure for post-menopausal women, and techniques have been simplified in recent years. The results of densitometry can predict the likelihood of fracture in people with low values fairly accurately, by comparing the patient’s value with the average for her age.

Previous or existing fractures are a clear sign of increased risk of further trouble. For instance, a previous fracture of the radius (a broken wrist) increases the future risk of a fractured hip by about 50%.

The cause of the osteoporosis is relevant. This disease has many known causes, although some cases are of unknown origin, or “idiopathic”. If the cause is known, it can help guide decisions about the need for vigorous treatment. For example, treatment with steroids (e.g. for asthma or severe rheumatoid arthritis), if it causes osteoporosis (a known side effect), produces a rapid loss of bone. Doses of steroids should therefore be kept as low as possible, but if this isn’t feasible, fracture-prevention treatment should be instituted.

Comment

The physician assessment of fracture risks can help the physician treating osteoporosis decide whether to recommend simple preventive measures (e.g. calcium supplements, hormone-replacement therapy, a specific exercise program), or more vigorous prophylaxis (e.g. drugs such as alendronate [Fosamax®], or nasal calcitonin [Miacalcin®]). Any older person can help postpone the increasing risks of osteoporosis-related fractures by ensuring continued regular physical activity and an appropriate calcium-rich diet.