Physical therapy may show small improvements in function compared with cognitive behavioral therapy, with no difference in pain intensity among stage I treatment recipients or stage II treatments among nonresponders with chronic low back pain.
In a multisite, sequential, multiple-assignment randomized OPTIMIZE trial, researchers evaluated nonpharmacologic strategies to treat chronic low back pain across two treatment stages with 52 weeks of follow-up. The researchers enrolled 749 adult participants across three US health systems who were randomly assigned to undergo 8 weeks of physical therapy (PT) or cognitive behavioral therapy (CBT). Nonresponders—defined as those who experienced less than 50% improvement in function—underwent a second randomization to either switch therapies or receive mindfulness-based treatment.
At 10 weeks, the patients receiving PT showed a 2.8-point greater improvement in the Oswestry Disability Index compared with those receiving CBT. The difference didn't meet the predefined minimum important difference of 6 points. The researchers observed no statistically significant differences in pain intensity between the participant groups, with a mean difference of 0.32 points on a scale randing from 0 to 10.
The response rates were 25% in the PT group and 14% in the CBT group; the likelihood of response was lower with CBT.
Secondary outcomes at 10 weeks showed greater improvement with PT across multiple PROMIS domains, including anxiety, fatigue, pain interference, physical function, sleep disturbance, and social role performance, whereas depression outcomes were similar between the groups. The patients undergoing PT also had fewer spinal injections compared with those who underwent CBT (4% vs 11%).
At 26 and 52 weeks, the functional outcomes continued to favor PT, with differences of 2.3 points at 26 weeks and 4.7 points at 52 weeks, while pain intensity didn't differ between the groups at any time point.
Among nonresponders, there were no statistically significant differences in function or pain intensity between the switching therapies and mindfulness groups at 52 weeks. Similar findings were observed among nonresponders to initial PT and CBT.
In exploratory analyses, adaptive interventions beginning with PT were associated with greater functional improvement at 52 weeks compared with those beginning with CBT, with differences of 6.1 points for mindfulness-based sequences and 3.3 points for switching-based sequences.
As a pragmatic study, the interventions were delivered with flexibility by 83 physical therapists and 57 mental health clinicians. Treatment initiation occurred in 63% of the patients receiving stage I treatment and 45% of those receiving stage II treatment. Study limitations included follow-up rates that were lower than expected and a sample size that was reduced because of the COVID-19 pandemic. The participants were also not blinded, and adherence was assessed based on session attendance rather than engagement with assigned activities.
Serious adverse events occurred in 5% of the patients, including 23 back surgeries, with similar rates across the groups.
“Patients with [chronic low back pain] may benefit from PT as first-line treatment. Among nonresponders, there were no differences in second-stage treatment with mindfulness or switching,” wrote lead study author Julie M. Fritz, PhD, PT, of the Department of Physical Therapy and Athletic Training at the College of Health at the University of Utah, and colleagues.
The study was funded by the Patient-Centered Outcomes Research Institute, with additional support from the National Center for Advancing Translational Sciences of the National Institutes of Health. Full disclosures of the study authors can be found in the study.
Source: Annals of Internal Medicine
