Australian and British researchers say the number of fractured hips is expected to nearly quadruple worldwide by mid-century as the population ages. This means an increasing burden on health care systems unless measures are taken to stem the rise.
University of Sydney bone specialist Philip Sambrook says one out of two women will break a bone during their lifetime, while the figure for men is one out of three or four.
The risk increases with age as bones become less dense and brittle with a disease called osteoporosis. Of all the bones that can be broken, Sambrook says hip fractures are the most devastating.
"A hip fracture is quite critical. It often means that people die in the first six months afterwards or are institutionalized," he explained. " They do not get back to their usual home."
Sambrook and a British colleague at the University of Southampton report in the journal "Lancet" that broken hips cost the world about $132 billion in direct and indirect costs in 1997, and the cost is rising because people over age 65 are becoming a bigger share of the population.
After reviewing many studies conducted in the past several years, they estimate that if the incidence of hip fracture remains as it is today, there will be more than six million cases in the year 2050, almost four times as many as there were in 1990.
But they note that fracture rates seem to be rising in many parts of the world, meaning there could be many millions more.
"Because this costs money, it is a burden not just for patients but it is quite a burden for government," he said. "We are all living longer and for whatever reason, perhaps because we are not having as much calcium in our diets or not exercising as much, some of these lifestyle factors that increase the risk mean that it is going to become an epidemic in the future."
Sambrook says drugs known as bisphosphonates have been the biggest advance against osteoporosis in the past decade. But they and other treatments reduce the risk of fractures only by half. With the number of worldwide fractures expected to grow dramatically, he says better therapies are needed.
He also says public health systems must make diagnosis of brittle bone disease more widespread for those at greatest risk. The standard test is a scan that determines bone mineral density.
"If we look ahead, we can often prevent this problem rather than waiting until it occurs," he noted. "So I think increased awareness of the condition and ways to reduce its impact are very important."