Background: Exercise is a first-line treatment for chronic low back pain (CLBP). It is unclear whether greater exercise adherence is associated with improvements in patient-reported outcomes such as pain and disability. We explored the relationship between exercise adherence and pain and disability in adults with CLBP.
Methods: We conducted a secondary analysis of the Cochrane systematic review, ‘Exercise therapy for chronic low back pain’, using the subset of trials that measured exercise adherence. We included studies of exercise compared to a non-exercise comparator. Random-effects meta-analysis was performed in R for pain and disability at the closest time point post-intervention. Exercise adherence was categorised as ‘Good’ (90-100%), ‘Moderate’ (70-89%), or ‘Poor’ (14-69%). Risk of bias of the included studies was done using the judgements provided by the Cochrane review.
Results: Data from 26 studies were included. There was some evidence for a dose-response relationship between exercise adherence with pain and disability. Compared to control, ‘Good’ adherence was associated with reduced pain by 17.83 points on a 100-point scale (95% CI -26.23 to -9.43) and disability by 9.69 points on a 100-point scale (95% CI -12.64 to -6.74). ‘Moderate’ adherence was associated with reduced pain by 6.93 points (95% CI -10.43 to -3.44) and disability by 3.80 points (95% CI -6.10 to -1.49). ‘Low’ adherence was associated with reduced PI by 7.50 points (95% CI -19.83 to -4.84) and disability by 3.35 points (95% CI -10.45 to -3.74). All included trials were deemed low risk of bias.
Conclusion: Greater adherence to exercise is associated with improved pain and disability in adults with CLBP. Further research is needed to understand the causal effect of adherence on patient-reported outcomes. Better reporting of exercise adherence in trials ins also needed to expand the evidence base.