A team of researchers based in Boston found that osteoarthritis patients who had total knee or hip joint replacement surgery (arthroplasty) were at increased risk of heart attack (myocardial infarction) in the early post-operative period.
The findings, published this week in Arthritis & Rheumatology, a journal of the American College of Rheumatology (ACR), 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, News-Medical.net reports.
According to the ACR, osteoarthritis is the most common form of arthritis, affecting 27 million Americans over the age of 25. As the joint cartilage and bone deteriorate, knee or hip replacement surgery may be the only option to relieve pain and stiffness, and restore mobility. Earlier studies estimate that 1.8 million arthroplasty procedures are performed each year worldwide, and that number may well increase as the population ages.
“While evidence shows that joint replacement surgery improves pain, function, and quality of life for the osteoarthritis patient, the impact [on] cardiovascular health has not been confirmed,” said lead study author Yuqing Zhang, D.Sc., Professor of Medicine and Epidemiology at Boston University School of Medicine in Boston, Massachusetts. The study examined whether joint replacement surgery reduces the risk of serious cardiovascular events among osteoarthritis patients.
The cohort 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 had been diagnosed with knee or hip osteoarthritis between January 2000 and December 2012, News-Medical reports.
Findings indicate that 306 patients in the arthroplasty group and 286 in the non-surgical group developed myocardial infarction during the follow-up period. The 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. The risk gradually declined over time, News-Medical reports. Venous thromboembolism was a significant risk during the first month and over time for those having total knee or total hip arthroplasty.
These 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,” Dr. Zhang wrote in conclusion. “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.”