When David T. Felson, MD, MPH, was introduced to a study of older people, known as the Framingham Heart Study, he realized that he could use the same group of people for his arthritis research.
His goal was to look backwards in time to determine what predisposed older people to osteoarthritis, the most common form of arthritis, said Felson, who during this time, from 1981-1984, was a clinical and research fellow in arthritis and connective tissue disease at Boston University School of Medicine.
The Framingham Osteoarthritis Study, which he started, was the first study to characterize the prevalence of the disease, and the first to obtain magnetic resonance imaging (MRI) on study participants. Among his findings, the MRIs showed that structural changes of osteoarthritis (OA), including meniscal tears, were common even in people without joint pain.
“We’re very excited to welcome Prof. Felson to Yale Rheumatology, and for him to partner with our junior faculty and fellows on clinical research projects,” Bucala said. “Prof. Felson has dedicated himself to training and mentoring clinical scientists, and many of the international leaders in musculoskeletal clinical research trained with him. Prof. Felson is a pioneer in the study of osteoarthritis, which has become one of the greatest medical challenges facing society. It is the leading cause of disability globally, afflicts 30% of all individuals over the age of 70, and incurs an annual U.S. GDP cost of at least $200 billion. Moreover, our scientific conceptions of osteoarthritis are rudimentary and we currently have no effective therapies to offer our patients.”
Obesity and OA
Felson pioneered studies showing that obesity caused knee osteoarthritis, and that weight loss prevented it. By introducing MRI into large-scale studies, he and his research group showed that synovium, the lining of the joints, and bone marrow lesions, injury lesions to bone deep to cartilage, were major sources of pain.
“What we found was that there were two structures that generated most of the pain in people with arthritis, and those include the synovium, which generates the fluid that accumulates when you get arthritis in the bone,” he said. As a consequence, these structures may become targets of treatment. This has changed the way people think about treating arthritis. “Up until now, people focused…on cartilage loss, and it turns out that cartilage loss probably doesn't have much to do with the pain people experience,” he said.
Felson’s research also confirmed a separate finding that overweight people who have bariatric surgery have less knee pain following their surgery. Interestingly, he also found that for people who are obese, sensitivity to pain is increased, notably in the hands.
Losing a lot of weight, he found, “was not necessarily about all the load that was present on their knees when they walked, when they were so overweight. It was more about some other process that was going on that just generally made them feel better and in less pain,” he said.
Joint Mechanics
Osteoarthritis is a difficult disease to treat. The loading of the joint, for example, creates damage that causes the joint to reshape itself.
“You can choose to treat the inflammation that's responding to that damage, or you can choose to treat the source of the damage, the abnormal mechanics and loading that are causing problems to the knee,” Felson said.
Felson’s recent research investigates the loading issue, in collaboration with engineers and physical therapists. His team’s paper, “Effect of Biomechanical Footwear on Knee Pain in People With Knee Osteoarthritis: The BIOTOK Randomized Clinical Trial,” was published in 2020 in JAMA. The study identified a special shoe that reorients the knee “so that you walk on parts of your knee that are not diseased,” he said.
Rheumatoid Arthritis
Felson developed the first core set of outcomes in rheumatoid arthritis (RA), then led the first joint American College and European League committee to define outcomes in RA trials. The recommended outcome, the ACR20, has been adopted by all regulatory agencies and is the major criterion used to approve drugs in RA.
“For rheumatoid arthritis, my group created the idea of a core set of outcomes, a concept that has now been adopted in multiple diseases,” he said. “We then led international efforts to standardize outcome measurement in rheumatoid arthritis, efforts that helped catalyze the dramatic improvements in treatment for this disease.”
Felson has received a Lifetime Achievement Award from the Osteoarthritis Research Society and was the inaugural recipient of the Clinical Research Award from the American College of Rheumatology. He also has cared for patients for over 30 years.
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