‘Little rationale’ for antidepressants in back pain, may be effective in osteoarthritis

Antidepressants are generally ineffective in treating back pain, but may be beneficial for osteoarthritis and sciatica, according to data published in BMJ.

“We realized that antidepressants are commonly used in clinical practice to reduce pain in people with back pain and osteoarthritis, and that several guidelines recommend their use,” Giovanni E. Ferreira, PhD, from the University of Sydney, said Rheumatology Healio. “However, all of the systematic reviews summarizing the results of randomized trials were either outdated or had methodological issues that did not allow a full assessment of the effects of these drugs.”

To update the evidence on the use of antidepressants for back pain and osteoarthritis, Ferreira and colleagues conducted a systematic review and meta-analysis. Eligible studies included randomized controlled trials comparing the effectiveness or safety – or both – of any antidepressant with placebo, in patients with lower back or neck pain, sciatica, or osteoarthritis of the hip or knee. Data sources included Medline, Embase, Cochrane Central Register of Controlled Trials, CINAHL, International Pharmaceutical Abstracts, ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform, inception to 15 November 2020, and updated. day on May 12, 2020.

In total, the researchers included 33 trials in their analysis. Two independent reviewers performed the data extraction, with pain and disability being the primary outcomes. The secondary outcome was safety, including any adverse events, serious adverse events, and the proportion of participants who withdrew due to adverse events. All pain and disability scores were converted to a scale of 0 to 100. The researchers used a random-effects model to calculate weighted mean differences and confidence intervals.

John E. Ferreira

Risk of bias was assessed using the Cochrane Collaboration tool, while the certainty of evidence was analyzed with the Framework for Assessing, Developing and Evaluating Recommendations (GRADE).

According to the researchers, moderate-certainty evidence showed that serotonin-norepinephrine reuptake inhibitors (SNRIs) reduced back pain (mean difference = –5.3; 95% CI –7.31 to –3 , 30) between 3 and 13 weeks. Meanwhile, low-certainty evidence showed SNRIs reduced osteoarthritis pain (–9.72; 95% CI, –12.75 to –6.69) between 3 and 13 weeks. Very low-certainty evidence demonstrated that SNRIs reduced sciatica at 2 weeks or less (–18.6; 95% CI, –31.87 to –5.33) but not at 3 to 13 weeks (–17 , 5; 95% CI, –42.9 to 7.89).

Additionally, low to very low-certainty evidence has shown that tricyclic antidepressants (TCAs) do not reduce sciatica at 2 weeks or less (–7.55; 95% CI, –18.25 to 3.15) but succeeded at 3 to 13 weeks (–15.95; 95% CI, –31.52 to –0.39) and at 3 to 12 months (–27; 95% CI, –36.11 to –17 , 89).

There was moderate-certainty evidence that SNRIs reduced disability due to back pain at 3 to 13 weeks (–3.55; 95% CI, –5.22 to –1.88) and disability due to osteoarthritis at 2 weeks or less (–5.1; 95% CI, –7.31 to –2.89), with low-certainty evidence between 3 and 13 weeks (–6.07; CI at 95%, –8.13 to –4.02). TCAs and other antidepressants, on the other hand, have failed to reduce the pain or disability due to back pain.

However, despite the results suggesting a possible benefit, Ferreira and colleagues advised caution when interpreting their results for osteoarthritis and sciatica.

“Most of the trials in people with osteoarthritis have been sponsored by pharmaceutical companies who have a lot to gain if the drug proves beneficial, and the trials in people with sciatica were small and poorly conducted and the results are therefore less certain, ”said Ferreira. “Taking antidepressants can increase your chances of experiencing certain side effects, and this should be discussed with your doctor or pharmacist.”

“Most low back pain guidelines currently recommend antidepressants for back pain and osteoarthritis,” he added. “Our results show that there is little reason to recommend antidepressants for people with back pain. For osteoarthritis and sciatica, although these drugs may be effective, the guidelines should stress that the current evidence is uncertain and that patients should also be made aware of this information to make an informed decision.