In trials of physiotherapy for chronic low back pain, clinical relevance is rarely interpreted, with great heterogeneity in the frameworks and thresholds used: a meta-research study

Effectiveness of physiotherapy modalities on persisting dyspnoea in long COVID: A systematic review and meta-analysis

BACKGROUND

Dyspnoea is often found months and years later in the "long-covid" syndrome, impairing quality of life and further perpetuating anxiety and post-traumatic stress disorders. Physiotherapy was recommended as a treatment in long-covid, but there is still insufficient evidence on its effectiveness.

METHODS

We conducted a systematic literature search on MEDLINE, PEDro, WOS, Scopus, VHL and the Cochrane Library until July 2023 (PROSPERO registration number: CRD42023427464). We selected comparative trials including adults with persistent breathlessness following COVID-19, regardless of the initial severity, for whom physiotherapy was implemented as a treatment for dyspnoea. We followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and assessed the study quality using the PEDro Scale.

RESULTS

19 studies that included 1292 adults fulfilled the inclusion criteria, of which 15 were randomised controlled trials and 4 non-randomised controlled trials. As for the rehabilitation modalities, 6 studies used respiratory muscle training, 6 studies used low to moderate intensity rehabilitation, 6 used high intensity rehabilitation and one used passive rehabilitation. The methods used between and within each group differed greatly, leading to an expected high heterogeneity of results. Nethertheless the random-effects model found a significant difference favouring physiotherapy (SMD -0.63, 95 CI [-1.03; -0.24], p < 0.001, I2 = 88 %). Subgroup analysis showed a significant effect in the high intensity rehabilitation group alone, with null heterogeneity.

CONCLUSION

In people suffering from dyspnoea following a SARS-CoV-2 infection, physiotherapy and especially pulmonary rehabilitation may help alleviate respiratory symptoms. Future studies will need to provide more consistent rehabilitation methods and better descriptions of them so as to reveal clear effects and avoid the confusion caused by using too many rehabilitation modalities.

The smallest worthwhile effect on pain intensity of exercise therapy for people with chronic low back pain: a discrete choice experiment study

OBJECTIVE: To identify the smallest worthwhile effect (SWE) of exercise therapy for people with non-specific chronic low back pain (CLBP). DESIGN: Discrete choice experiment. METHODS: The SWE was estimated as the lowest reduction in pain that participants would consider exercising worthwhile, compared to not exercising i.e., effects due to natural history and other components (e.g., regression to the mean). We recruited English-speaking adults in Australia with non-specific CLBP to our online survey via email obtained from a registry of previous participants and advertisements on social media. We used discrete choice experiment to estimate the SWE of exercise compared to no exercise for pain intensity. We analysed the discrete choice experiment using a mixed logit model, and mitigated hypothetical bias through certainty calibration, with sensitivity analyses performed with different certainty calibration thresholds. RESULTS: Two-hundred and thirteen participants completed the survey. The mean age (±SD) was 50.7±16.5, median (IQR) pain duration 10 years (5-20), and mean pain intensity (±SD) was 5.8±2.3 on a 0-10 numerical rating scale. For people with CLBP the SWE of exercise was a between-group reduction in pain of 20%, compared to no exercise. In the sensitivity analyses, the SWE varied with different levels of certainty calibration; from 0% without certainty calibration to 60% with more extreme certainty calibration. CONCLUSION: This patient-informed threshold of clinical importance could guide the interpretation of findings from randomised trials and meta-analyses of exercise therapy compared to no exercise.