Broken hip tied to increased risk of stroke

While suffering a stroke is already known to raise the risk of breaking your hip, new research hints that the reverse might also be true.

The study out of Taiwan found that patients with a broken hip had more than a 50 percent increased risk of having a stroke within a year of their injury compared to similar patients with no fractures.

However, the finding is not enough to be certain that hip fractures, which account for more than 320,000 hospital admissions every year in the U.S., can actually cause a stroke - the nation's third leading cause of death.

"It is known that the risk of hip fracture is high in those with strokes. We thought that was because strokes lead to falls and bone loss," Dr. Steven Cummings of the University of California, San Francisco, told Reuters Health in an e-mail.

"This new study makes me think that both hip fractures and strokes are partly due to an underlying cause of aging," added Cummings, who was not involved in the current research but recently led a separate study of hip fractures.

Jiunn-Horng Kang of National Taiwan University, in Taipei, and his colleagues studied about 8,400 Taiwanese patients averaging 64 years old.

Among 256 patients who suffered a stroke over the course of a year, 4.1 percent had broken their hips previously, compared to 2.7 percent of those who hadn't. That translated into more than a 50 percent increased risk of stroke after the injury.

The difference in vulnerability held after accounting for other stroke risk factors such as diabetes and heart disease.

Still, what might be responsible for the added risk remains unclear, report the researchers in the journal Stroke. They point to the potential roles of physical inactivity and psychological distress that comes after a broken hip, and the complications that can arise during hospitalization and surgery.

A "common hidden cause" might also underlie both broken hips and stroke, noted Cummings.

"We know that those with cardiovascular disease have lower bone density and most studies, like ours, show that low bone mineral density is associated with a greater risk of dying of stroke," he said.

To potentially mitigate the risk of stroke after a fracture, Cummings advises taking a baby aspirin every day and doing everything else possible to control blood pressure. This can include taking medications and getting adequate exercise, as well as limiting alcohol and salt in the diet.

"Patients with hip fracture should get preventive primary care," he added, "not just an orthopedic fix."

SOURCE: Stroke, online December 23, 2010.