Over 32 million U.S. adults and over 500 million individuals worldwide suffer from osteoarthritis, making it the most prevalent type of disease. It mostly affects the hands, hips, and knees. People who suffer from osteoarthritis have a gradual breakdown of the cartilage that cushions their joints. Inflammation, or swelling, of the joint, which can be painful, is often a complication of arthritis.
A new study to be presented at next week’s annual conference of the Radiological Society of North America suggests that anti-inflammatory pain medications like ibuprofen and naproxen may actually make knee joint inflammation worse in the long run in patients with osteoarthritis.
Over 32 million U.S. adults and over 500 million individuals worldwide suffer with osteoarthritis, making it the most prevalent type of the disease. It mostly affects the hands, hips, and knees. People who suffer from osteoarthritis have a gradual breakdown of the cartilage that cushions their joints. Inflammation, or swelling, of the joint, which can be painful, is often a complication of arthritis.
For the pain and inflammation associated with osteoarthritis, non-steroidal anti-inflammatory drugs (NSAIDs) are frequently recommended. However, little is known about how these medications affect disease development over the long term.
“To date, no curative therapy has been approved to cure or reduce the progression of knee osteoarthritis,” says the study’s lead author, Johanna Luitjens, postdoctoral scholar in the Department of Radiology and Biomedical Imaging at the University of California, San Francisco. “NSAIDs are frequently used to treat pain, but it is still an open discussion of how NSAID use influences outcomes for osteoarthritis patients. In particular, the impact of NSAIDs on synovitis, or the inflammation of the membrane lining the joint, has never been analyzed using MRI-based structural biomarkers.”
Dr. Luitjens and his team wanted to find out if there was a link between the use of NSAIDs and synovitis in people with osteoarthritis of the knee, and they also wanted to see how treatment with NSAIDs changes the structure of the joint over time.
“Synovitis mediates development and progression of osteoarthritis and may be a therapeutic target,” Dr. Luitjens adds. “Therefore, the goal of our study was to analyze whether NSAID treatment influences the development or progression of synovitis and to investigate whether cartilage imaging biomarkers, which reflect changes in osteoarthritis, are impacted by NSAID treatment.”
The study compared a group of 277 participants from the Osteoarthritis Initiative cohort who had moderate to severe osteoarthritis and had been taking NSAIDs for at least a year between the study’s baseline and four-year follow-up with a control group of 793 participants who had not received NSAID treatment. An initial and four-year 3T MRI of the knee was performed on each subject. Biomarkers of inflammation were used to give the images a score.
The course of arthritis was tracked using noninvasive biomarkers such as cartilage thickness, composition, and other MRI data.
The findings revealed no long-term advantages of NSAID use. Participants taking NSAIDs had worse baseline joint inflammation and cartilage quality than the control group, and these problems persisted over the four-year follow-up.
“In this large group of participants, we were able to show that there were no protective mechanisms from NSAIDs in reducing inflammation or slowing down progression of osteoarthritis of the knee joint,” Dr. Luitjens adds. “The use of NSAIDs for their anti-inflammatory function has been frequently propagated in patients with osteoarthritis in recent years and should be revisited, since a positive impact on joint inflammation could not be demonstrated.”
Dr. Luitjens says that there are several possible reasons why taking NSAIDs makes synovitis worse.
“On the one hand, the anti-inflammatory effect that normally comes from NSAIDs may not effectively prevent synovitis, with progressive degenerative change resulting in worsening of synovitis over time,” she explains. “On the other hand, patients who have synovitis and are taking pain-relieving medications may be physically more active due to pain relief, which could potentially lead to worsening of synovitis, although we adjusted for physical activity in our model.”
Dr. Luitjens suggested prospective, randomized studies to prove NSAIDs’ anti-inflammatory effects.
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