Pain catastrophising and kinesiophobia mediate pain and physical function improvements with Pilates exercise in chronic low back pain: a mediation analysis of a randomised controlled trial

Lianne Wood; Geronimo Bejarano; Ben Csiernik; Gisela C Miyamoto; Gemma Mansell; Jill A Hayden; Martyn Lewis; Aidan G Cashin

doi:10.1016/j.jphys.2023.05.008

Pain catastrophising and kinesiophobia mediate pain and physical function improvements with Pilates exercise in chronic low back pain: a mediation analysis of a randomised controlled trial

J Physiother. 2023 Jul;69(3):168-174. doi: 10.1016/j.jphys.2023.05.008. Epub 2023 Jun 3.

Authors

Lianne Wood¹, Geronimo Bejarano², Ben Csiernik³, Gisela C Miyamoto⁴, Gemma Mansell⁵, Jill A Hayden⁶, Martyn Lewis⁷, Aidan G Cashin⁸

Affiliations

¹ Spinal Surgical Division, Nottingham University Hospitals NHS Trust, Nottingham, UK; School of Medicine, Keele University, Newcastle-under-Lyme, UK; Faculty of Health and Life Sciences, University of Exeter, Exeter, UK. Electronic address: l.wood2@exeter.ac.uk.
² University of Texas Health Science Center (UTHealth), Austin, Texas, USA.
³ Department of Health Sciences, Ontario Tech University, Oshawa, Ontario, Canada.
⁴ Masters and Doctoral Program in Physical Therapy, Universidade Cidade de São Paulo, São Paulo, Brazil.
⁵ School of Psychology, College of Health & Life Sciences, Aston University, Aston Triangle, Birmingham, UK.
⁶ Department of Community Health and Epidemiology, Dalhousie University, Halifax, Canada.
⁷ School of Medicine, Keele University, Newcastle-under-Lyme, UK.
⁸ Centre for Pain IMPACT, Neuroscience Research Australia, Sydney, Australia; School of Health Sciences, Faculty of Medicine & Health, University of New South Wales, Sydney, Australia.

PMID: 37277290
DOI: 10.1016/j.jphys.2023.05.008

Abstract

Question: How much are the reductions in pain intensity and improvements in physical function from Pilates exercise mediated by changes in pain catastrophising and kinesiophobia?

Design: This was a secondary causal mediation analysis of a four-arm randomised controlled trial testing Pilates exercise dosage (once, twice or thrice per week) against a booklet control.

Participants: Two hundred and fifty-five people with chronic low back pain.

Data analysis: All analyses were conducted in R software (version 4.1.2) following a preregistered analysis plan. A directed acyclic graph was constructed to identify potential pre-treatment mediator-outcome confounders. For each mediator model, we estimated the intervention-mediator effect, the mediator-outcome effect, the total natural indirect effect (TNIE), the pure natural direct effect (PNDE), and the total effect (TE).

Results: Pain catastrophising mediated the effect of Pilates exercise compared with control on the outcomes pain intensity (TNIE MD -0.21, 95% CI -0.47 to -0.03) and physical function (TNIE MD -0.64, 95% CI -1.20 to -0.18). Kinesiophobia mediated the effect of Pilates exercise compared with control on the outcomes pain intensity (TNIE MD -0.31, 95% CI -0.68 to -0.02) and physical function (TNIE MD -1.06, 95% CI -1.70 to -0.49). The proportion mediated by each mediator was moderate (21 to 55%).

Conclusion: Reductions in pain catastrophising and kinesiophobia partially mediated the pathway to improved pain intensity and physical function when using Pilates exercise for chronic low back pain. These psychological components may be important treatment targets for clinicians and researchers to consider when prescribing exercise for chronic low back pain.

Keywords: Exercise; Low back pain; Mediation analysis; Physical therapy; Pilates.

Publication types

Randomized Controlled Trial
Research Support, Non-U.S. Gov't

MeSH terms

Chronic Pain* / psychology
Chronic Pain* / therapy
Exercise Movement Techniques*
Exercise Therapy
Humans
Kinesiophobia
Low Back Pain* / psychology
Low Back Pain* / therapy
Mediation Analysis