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• Posted May 31, 2023

Low-Dose Colchicine Might Prevent or Delay Knee, Hip Replacements

An anti-inflammatory drug that has been around for over 2,000 years might help delay a very modern problem: hip and knee replacements.

That's the suggestion of a new study finding that older adults who used the drug -- called colchicine -- were less likely to need hip or knee replacement surgery over the next two years, versus those given placebo pills.

The study, published May 30 in the Annals of Internal Medicine, does come with a big caveat, researchers noted: The patients were part of a trial testing colchicine for warding off heart trouble -- not joint replacements.

So the findings do not prove the medication actually stalled the progression of knee or hip osteoarthritis. That's the common, age-related form of arthritis where the cartilage cushioning the joints gradually breaks down.

But the results do make a "strong argument" for studying colchicine as a treatment for osteoarthritis, said lead researcher Michelle Heijman, of Sint Maartens Clinic, in Nijmegen, the Netherlands.

Until then, she said, the drug cannot be recommended as a treatment for the joint disease.

As it stands, medications for osteoarthritis offer pain relief, but there are none that can slow the underlying joint destruction.

Colchicine is an oral drug that has long been prescribed for a different form of arthritis called gout. Doctors also sometimes use it to treat pericarditis, where the sac around the heart becomes inflamed.

More recently, in 2020, a clinical trial found that colchicine benefits people who'd recently suffered a heart attack: It reduced their risk of further heart complications and stroke over the next two years, in comparison to a placebo.

Colchicine works by inhibiting the body's production of particular inflammatory proteins -- ones that have been implicated in osteoarthritis progression. So Heijman's team reasoned that patients given colchicine in the 2020 trial might also have had a lower likelihood of hip or knee replacement surgery.

To find out, they took a second look at the trial data.

The study involved over 5,500 patients who were 66, on average. Half were randomly assigned to take a low dose of colchicine (0.5 milligrams per day), while the other half received a placebo.

Heijman's team found that over two-plus years, 2.5% of colchicine patients underwent hip or knee replacement surgery, versus 3.5% of placebo patients.

A shortfall of the data is that there was no information on whether people had osteoarthritis. But, Heijman said, the vast majority of hip and knee replacements are done because of severe osteoarthritis. And the researchers think the findings do reflect an effect of colchicine on arthritis progression.

However, Heijman said, this trial focused on heart disease patients, so it cannot be used to change treatment guidelines for osteoarthritis.

"That's why we want to conduct a follow-up study that is specifically aimed at osteoarthritis," she said. "If we can confirm that colchicine works, we can finally offer osteoarthritis patients a safe and effective therapy."

Dr. Linda Russell, a rheumatologist at the Hospital for Special Surgery, in New York City, agreed that colchicine should be further studied as an osteoarthritis treatment.

She noted that colchicine has a long history of use, and it is "relatively safe and well-tolerated."

In fact, colchicine's use dates back a couple of thousand years, when the ancient Greeks employed it as a laxative. Accordingly, its most common side effects are gastrointestinal, including abdominal pain, nausea and diarrhea.

Like Heijman, Russell said the new findings are not enough to prove that colchicine delays joint replacements. For one, it's not clear how many patients already had surgery planned before they entered the trial.

For now, Russell said that people with osteoarthritis can do some things to prevent or delay a joint replacement: lose weight, if needed, and strengthen the muscles supporting the affected joint.

Those tactics, Russell said, may both slow the underlying disease progression and ease chronic pain -- the key reason that people opt for surgery.

More information

The Arthritis Foundation has more on osteoarthritis treatment.

SOURCES: Michelle Heijman, MSc, junior researcher, Sint Maartens Clinic, Nijmegen, the Netherlands; Linda A. Russell, MD, rheumatologist, director, perioperative medicine, Hospital for Special Surgery, New York City; Annals of Internal Medicine, May 30, 2023