Exercise treatment effect modifiers in persistent low back pain: an individual participant data meta-analysis of 3514 participants from 27 randomised controlled trials

Jill A Hayden*, Maria N Wilson, Samuel Stewart, Jennifer L Cartwright, Andrea O Smith, Richard D Riley, Maurits van Tulder, Tom Bendix, Francesca Cecchi, Leonardo O P Costa, Ninna Dufour, Manuela L Ferreira, Nadine E Foster, Maruti R Gudavalli, Jan Hartvigsen, Pieter Helmhout, Jan Kool, George A Koumantakis, Francisco M Kovacs, Tiina KuukkanenAudrey Long, Luciana G Macedo, Luciana A C Machado, Chris G Maher, Wolf Mehling, Giovanni Morone, Tom Peterson, Eva Rasmussen-Barr, Cormac G Ryan, Tuulikki Sjögren, Rob Smeets, J Bart Staal, Monica Unsgaard-Tøndel, Henry Wajswelner, Ella W Yeung, Chronic Low Back Pain IPD Meta-Analysis Group

*Corresponding author for this work

Research output: Contribution to journal(Systematic) Review article peer-review

46 Citations (Web of Science)
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BACKGROUND: Low back pain is one of the leading causes of disability worldwide. Exercise therapy is widely recommended to treat persistent non-specific low back pain. While evidence suggests exercise is, on average, moderately effective, there remains uncertainty about which individuals might benefit the most from exercise.

METHODS: In parallel with a Cochrane review update, we requested individual participant data (IPD) from high-quality randomised clinical trials of adults with our two primary outcomes of interest, pain and functional limitations, and calculated global recovery. We compiled a master data set including baseline participant characteristics, exercise and comparison characteristics, and outcomes at short-term, moderate-term and long-term follow-up. We conducted descriptive analyses and one-stage IPD meta-analysis using multilevel mixed-effects regression of the overall treatment effect and prespecified potential treatment effect modifiers.

RESULTS: We received IPD for 27 trials (3514 participants). For studies included in this analysis, compared with no treatment/usual care, exercise therapy on average reduced pain (mean effect/100 (95% CI) -10.7 (-14.1 to -7.4)), a result compatible with a clinically important 20% smallest worthwhile effect. Exercise therapy reduced functional limitations with a clinically important 23% improvement (mean effect/100 (95% CI) -10.2 (-13.2 to -7.3)) at short-term follow-up. Not having heavy physical demands at work and medication use for low back pain were potential treatment effect modifiers-these were associated with superior exercise outcomes relative to non-exercise comparisons. Lower body mass index was also associated with better outcomes in exercise compared with no treatment/usual care. This study was limited by inconsistent availability and measurement of participant characteristics.

CONCLUSIONS: This study provides potentially useful information to help treat patients and design future studies of exercise interventions that are better matched to specific subgroups. PROTOCOL PUBLICATION: https://doi.org/10.1186/2046-4053-1-64.

Original languageEnglish
Pages (from-to)1277-1278
Number of pages16
JournalBritish Journal of Sports Medicine
Issue number21
Early online date28 Nov 2019
Publication statusPublished - Nov 2020



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