Hip And Knee Replacements Up Heart Attack Risk, Study Finds

A new study finds that osteoarthritis patients who have total hip or knee replacement surgery have a greater risk for a heart attack during the first month following the procedure. The study reveals, however, that the long-term risk of heart attack did not remain, while the risk for blood clots in veins and lungs (venous thromboembolism) persisted for years after the procedure.

Lead study author Yuqing Zhang, D.Sc., Professor of Medicine and Epidemiology at Boston University School of Medicine in Boston, Massachusetts, explains:

“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. Our study examines if joint replacement surgery reduces risk of serious cardiovascular events among osteoarthritis patients.”

Most Common Form of Arthritis

Osteoarthritis is the most common form of arthritis, affecting 27 million Americans over the age of 25 according to the American College of Rheumatology (ACR). As the joint cartilage and bone deteriorates, knee or hip replacement surgery may be the only option to relieve pain and stiffness, and restore mobility.

Previous studies estimate that 1.8 million arthroplasty procedures are performed each year worldwide, and that number may increase as the population ages.

The study involved 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.

306 patients in the arthroplasty group and 286 in the non-surgical group developed myocardial infarction during the follow-up period.

Blood Clot Risks

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,” concludes Dr. 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.”

Na Lu, Devyani Misra, Tuhina Neogi, Hyon K.Choi and Yuqing Zhang
Total Joint Arthroplasty and the Risk of Myocardial Infarction – A General Population, Propensity Score-Matched Cohort Study
Arthritis & Rheumatology; August 31, 2015. DOI: 10.1002/art.39246

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