Low-dose colchicine lowers incidence of knee and hip replacements, study finds

Key takeaways:

• Benefits of low-dose colchicine were consistent in men over a median follow-up period of 28.6 months.
• Due to low statistical power, it is unknown whether the benefits of colchicine extended to women.

A 0.5 mg daily dose of colchicine was linked to a 31% lower incidence of total knee and total hip replacement in patients with chronic coronary artery disease compared with placebo, according to an exploratory analysis of the LoDoCo2 trial.

Previous evidence has suggested that short-term use of colchicine may be beneficial in patients with osteoarthritis and clinical features of joint inflammation; however, the treatment is not currently recommended for the disease, Michelle W.J. Heijman, MSc, of the department of research at Sint Maartenskliniek hospital in the Netherlands, and colleagues wrote in Annals of Internal Medicine.

“In addition, the long-term effects of colchicine on the affected joints have not been assessed,” they wrote.

To establish whether colchicine could reduce the need for total knee replacement (TKR) and total hip replacement (THR), the researchers conducted an exploratory analysis of LoDoCo2, a randomized controlled trial in which participants received either 0.5 mg of colchicine or placebo daily over the course of more than 2 years.

A total of 2,762 participants received colchicine and 2,760 received placebo. Both groups had a mean age of 65 years. Women comprised 16.5% and 14.1% of the colchicine and placebo groups, respectively.

The researchers reported that 68 patients (2.5%) in the colchicine group and 97 patients (3.5%) in the placebo group underwent TKR or THR, totaling incidence rates of 0.9 and 1.3 per 100 person-years, respectively (HR = 0.69; CI, 0.51-0.95).

In sensitivity analyses, the incident rates per 100 person-years remained similar to overall findings when excluding TKR and THR incidences within the first 3 months (0.78 vs. 1.29) and first 6 months (0.66 vs. 1.14) and when excluding participants with gout at baseline (0.88 vs. 1.3).

While the results were consistent for men, due to the low number of events among women in the study, “there was insufficient statistical power to determine whether the benefits of colchicine on the incidence of hip and knee replacement may have extended to women,” the researchers wrote.

They added that colchicine has been used to treat several other diseases and is considered to have a preferable safety profile, “which makes it a good candidate for treatment of osteoarthritis over longer periods.”

The study limitations included the absence of data on histories of osteoarthritis, joint pain and physical function, according to the researchers. Because of this, they used a less frequently used outcome for investigating drug effectiveness in osteoarthritis — TKR and THR. The lack of data on TKR and THR before the study “makes this outcome suboptimal,” the researchers wrote.

Heijman and colleagues concluded that colchicine “may slow the progression of osteoarthritis,” but “this needs to be confirmed in an appropriately designed prospective placebo-controlled trial.”