FRIDAY, Nov. 9, 2012 (HealthDay News) -- Patients who undergo total hip replacement are at greatly increased risk for stroke in the first few weeks after their surgery, a large new study says.
The findings suggest that elderly people need to weigh the benefits of hip replacement against the risk of stroke, according to the researchers.
The investigators compared more than 66,000 people in Denmark who had total hip replacement to nearly 200,000 people who did not have the procedure. The average age of the people in the study was 72. Most were white and female.
The hip replacement patients had a 4.4-fold increased risk of hemorrhagic stroke -- bleeding in the brain -- in the two weeks after surgery, compared to people in the general population. They also had a nearly 4.7-fold increased risk of ischemic stroke -- from blocked blood flow to the brain -- during that time, the study authors found.
The risk of ischemic stroke stayed higher for six weeks after hip replacement and the risk for hemorrhagic stroke stayed higher for 12 weeks, according to the study published online Nov. 6 in the journal Stroke.
The risk of stroke declined after that time and returned to normal after one year, according to study lead author Frank de Vries, an assistant professor of pharmacoepidemiology at Utrecht University in the Netherlands.
The researchers also found that taking aspirin lowered hip replacement patients' risk of stroke by as much as 70 percent. Other medications had no effect.
Each year, about 1 million hip replacements are performed worldwide, including about 300,000 in the United States. The researchers said it was important to assess the risk of stroke in the weeks after hip replacement surgery.
"There is an increasing tendency to decrease the length of hospital stay because of improved therapy and because of strategies to reduce costs and mobilize patients as soon as possible," de Vries said in a journal news release. "It makes sense to evaluate the risk of stroke two weeks after surgery," he concluded.
The American Academy of Orthopaedic Surgeons has more about total hip replacement.