Knee and hip replacements may up risk of heart attack

Osteoarthritis patients who undergo total knee or hip joint replacement surgery may be at an increased risk of heart attack in the short-term, researchers have warned.
The findings indicate that long-term risk of heart attack did not persist, but the risk for venous thromboembolism - blood clot in veins and lungs - remained years after the procedure.
As the joint cartilage and bone deteriorates, knee or hip replacement surgery, known as arthroplasty, may be the only option to relieve pain and stiffness, and restore mobility in sufferers of osteoarthritis.
"While evidence shows that joint replacement surgery improves pain, function, and quality of life for the osteoarthritis patient, the impact of cardiovascular health has not been confirmed," said lead study author Yuqing Zhang, professor of Medicine and Epidemiology at Boston University School of Medicine in US.

"Our study examines if joint replacement surgery reduces risk of serious cardiovascular events among osteoarthritis patients," Zhang said.
The study included 13,849 patients who underwent total knee replacement surgery and 13,849 matched controls who did not have surgery.

Patients were 50 years of age or older and diagnosed with knee or hip osteoarthritis between January 2000 and December 2012.
Findings indicate that 306 patients in the arthroplasty group and 286 in the non-surgical group developed heart attack (myocardial infarction) during the follow-up period.
Risk of heart attack was significantly higher during the first postoperative month in those who had knee replacement surgery compared to those in the non-surgical group, and gradually declined over time.

Venous thromboembolism was a significant risk during the first month and over time for those having total knee or total hip arthroplasty.
"Our findings provide the first general population-based evidence that osteoarthritis patients who have total knee or total hip replacement surgery are at increased risk of heart attack in the immediate postoperative period," said Zhang.
"The long-term risk of heart attack was insignificant, but risk of blood clots in the lung remained for years after surgery to replace a hip or knee damaged by osteoarthritis," said Zhang.
The study was published in the journal Arthritis and Rheumatology.