Hip fracture linked to increased stroke risk
MedWire News: Patients with hip fracture have an increased risk for stroke in the year following injury, researchers report.
The association between cardiovascular disease and hip fracture has attracted attention in recent years, and stroke is a recognized risk factor for hip fracture, note Herng-Ching Lin (Taipei Medical University, Taiwan) and colleagues.
"Several factors are thought to concurrently affect the vascular system and regulation of bone formation," explain the researchers who hypothesized that patients with hip fractures may experience several unfavorable physiological changes that predispose them to stroke.
To test this, Lin and team investigated the frequency of stroke during a 1-year follow-up period after a hip fracture.
They calculated the relative risk for stroke among 2101 hip-fracture patients (mean age 63.9 years) compared with 6303 non-fracture controls matched for age, gender, and year of index healthcare use.
During the follow-up period, the rate of stroke was significantly higher in the hip-fracture patients compared with controls at 4.1% versus 2.7%, respectively, corresponding to a 1.55-fold greater risk for stroke among the patients with fractures.
Furthermore, after adjusting for patients' geographic location, monthly income, and major cardiovascular risk factors (hypertension, diabetes, heart disease, and hyperlipidemia at baseline), patients with hip fracture were still 1.53 times more likely to have a stroke relative to the control group.
Writing in the journal Stroke, Lin and co-authors point out that the mechanisms mediating stroke occurrence among patients with hip fracture are unclear. They suggest that several factors may be involved, including disruption or deterioration of pre-existing cardiovascular risk triggered by physical inactivity, psychological distress, and pain.
In addition, deep vein thrombosis, fat embolization, and pulmonary embolization in the acute and postoperative periods may be involved, they say.
Although the mechanisms are unknown, the researchers conclude: "Our study suggests that physicians should be proactive to prevent strokes given the subsequent higher risk of stroke among patients with hip fracture."
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By Laura Dean