CBT Shows Small, Significant Benefit for Chronic Pain Patients

By Anne Harding

September 09, 2020

NEW YORK (Reuters Health) - Cognitive behavioral therapy (CBT) has small beneficial effects for reducing pain, disability and distress in patients with chronic non-headache, non-cancer pain, according to a new Cochrane review of psychological therapies.

While the evidence base for CBT was solid, given the low quality of evidence for behavioral therapy (BT) and acceptance and commitment therapy (ACT), "we are very uncertain about benefits or lack of benefits of these treatments for adults with chronic pain," Dr. Amanda Williams of University College London and her colleagues write in the Cochrane Database of Systematic Reviews.

Chronic pain lasting for more than three months is difficult to treat, they note, and can lead to patients becoming disabled, socially isolated, anxious and depressed. To update a 2012 review, the authors analyzed 75 randomized controlled trials including 9,401 patients with fibromyalgia, chronic low-back pain, rheumatoid arthritis, mixed chronic pain and other conditions.

Fifty-nine studies looked at CBT. Those comparing CBT with an active control found moderate-quality evidence of significant benefit for pain (standardized mean difference, -0.09) and disability (SMD, -0.12), and borderline-significant improvement in distress (SMD, -0.09).

Compared with treatment as usual (TAU), CBT significantly reduced pain (SMD, -0.22, moderate-quality evidence), disability (SMD, -0.32, low-quality evidence) and distress (SMD -0.34, moderate-quality evidence).

The eight studies of BT included 647 participants, and found no evidence of benefit over active control or TAU. There were five studies of ACT, including 443 participants. ACT was not better than active control for pain, disability or distress at the end of treatment, although two studies found a large and significant benefit on disability (SMD, -2.56, very-low quality evidence) at follow-up.

Two studies of ACT versus TAU showed large benefits for pain (SMD, -0.83, very-low-quality evidence), but no significant change in disability or distress.

For each of the three treatments studied, evidence for adverse events (AEs) was of very low quality, and recording and reporting of AEs was inadequate, the authors state.

"It feels like we've got enough trials to kind of know where we are," Dr. Williams told Reuters Health by phone. "We don't need to keep asking the same questions."

She said she and her colleagues were somewhat surprised to see the lack of benefit of ACT, given that there have been positive systematic reviews, "and lots of people are terribly keen on it."

She added: "If you read the papers carefully, their data is not as good as you would think from the abstract, there's a bit of a spin around this, and that shouldn't be deciding what patients get."

Investigators need to do a better job of paying attention to the potential adverse effects of psychological therapies, such as worsening depression and pain, Dr. Williams added.

"There's a risk of doing people harm, and psychologists don't think enough about it," she said. "We ought to be thinking much more carefully about dropouts, and I think there's somewhat of a tendency to see it as the patient's fault."

SOURCE: https://bit.ly/2QZryXn Cochrane Database of Systematic Reviews, online August 12, 2020.