A long-running arthritis study at the University of North Carolina at Chapel Hill has been awarded a $3.25 million grant from the Centers for Disease Control and Prevention to follow up on patients first studied 20 years ago.

More than 3,200 men and women from from rural Johnston County are participating in the Johnston County Osteoarthritis Project, which is studying osteoarthritis in the hips and knees. Project organizers note that osteoarthritis is the most common form of arthritis after age 45. It is also more common and more likely to cause disability in rural southerners.

Among the study’s goals are finding out what causes osteoarthritis, how to prevent it and how to help those who already have it. The new funding will support follow up on participants who enrolled study 20 years ago. The follow-up aims to see if participants have any difference in the lengths of one leg compared to the other.

“We have shown leg length inequality to be associated with osteoarthritis in the hips and knees,” said Dr. Joanne Jordan, principal investigator of the study and director of UNC Rheumatology/Thurston Arthritis Research Center said in a statement. “By studying people for a longer time, we will be able to find out if a leg length inequality actually causes the arthritis over the long-term or makes pain, symptoms, and disability more likely.”

The 20-year follow up will also evaluate weight maintenance compared to weight loss as part of the study. Jordan said that while weight loss decreases osteo arthritis risks, maintaining weight does not protect people from getting knee osteoarthritis, Jordan said. Investigators will be studying whether weight maintenance could be protective for late-onset osteoarthritis..

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