Do Opioids Have a Role in the Management of Knee and Hip Osteoarthritis?

Opioids show minimal benefits for osteoarthritis (OA) symptoms and may increase safety risks, according to study findings published in Arthritis Care & Research.

Opioids have been used to manage chronic pain, especially for patients with OA in whom nonsteroidal anti-inflammatory drugs or other therapies are contraindicated. However, the efficacy and safety of opioids for chronic OA pain has recently come under the scrutiny. In a review and meta-analysis of randomized controlled trials (RCTs) of patients with knee and/or hip OA, investigators aimed to determine differences in safety and efficacy between strong and weak/intermediate opioids and placebo.

Criteria for study inclusion were placebo-controlled trials of oral opioids in patients with knee and/or hip OA. Researchers collected data for all dosage groups and classified the opioids as “strong” or “weak/intermediate.” They also gathered data for all reported time points, which were grouped into four 4 categories, including 2 weeks, 4 weeks, 8 weeks, and 12 weeks. Outcome data for pain (primary outcome) and quality of life, sleep quality, discontinuation rates, rate of adverse events, and others (secondary outcomes) were also collected. Researchers calculated standardized mean differences (SMDs) and confidence intervals and conducted meta-analyses of strong and weak/intermediate opioids for pain and safety at each time point.

Data from 9283 participants in 18 RCTs were included in the study. At each follow-up time point from 2 to 12 weeks, opioids vs placebo were shown to have a slight effect on pain. Investigators observed the largest benefits at 2 and 4 weeks with SMDs of -0.27 (95% CI, -0.37 to -0.17; 11 RCTs) and -0.28 (95% CI -0.38 to -0.17; 9 RCTs), respectively. Between 4 and 8 weeks, the benefit of opioids on pain decreased by 32%. At 12 weeks, the SMD was -0.21 (95% CI, -0.30 to -0.11; 10 RCTs). The overall benefits of opioids on factors such as quality of life, quality of sleep, and depression were not significant. Small benefits were observed in sleep quality for both strong and weak/intermediate opioids; quality of life was found to be very low quality evidence; and depression scores at 12 weeks were slightly worse in patients receiving opioids vs placebo.

Strong vs weak/intermediate opioids were less effective for pain relief compared with the placebo. Effect sizes for weak/intermediate opioids were greater than those for strong opioids by 19% at 2 weeks, 32% at 4 weeks, and 130% at 8 weeks, and decreased to 16% larger at 12 weeks. In addition, patients receiving opioids were 1.5 times more likely to experience any adverse event; they were also more likely to discontinue treatment because of these adverse events.

Overall, the findings showed that compared with placebo, opioids had only small benefits in terms of pain and function in OA. In addition, treatment with opioids of any strength had little benefit on quality of life, but increased risk for harms. Researchers also demonstrated that strong vs weak/intermediate opioids had lower efficacy and worse safety in the management of OA.

The study was limited by its reliance on data from RCTs, which could be of varying quality, and potential reporting bias.

Researchers concluded, “In light of this evidence and in the context of a rapidly shifting paradigm for pain management, clinicians and policy makers should reconsider the utility of opioids in the management of OA.”

Reference

Osani MC, Lohmander LS, Bannuru RR. Is there any role for opioids in the management of knee and hip osteoarthritis? A systematic review and meta‐analysis [published online June 25, 2020]. Arthritis Care Res. doi:10.1002/acr.24363