Are Changes in Fear-Avoidance Beliefs and Self-Efficacy Mediators of Discharge Function and Pain in Patients With Acute and Chronic Low Back Pain?

Study Design Retrospective study. Background: Fear-avoidance beliefs and self-efficacy are considered important determinants of outcomes in patients with low back pain (LBP). Few studies have conducted longitudinal analyses to determine whether meaningful changes in functional outcomes are mediated by changes in these psychological factors. Objectives: To examine the mediating role of changes in fear-avoidance beliefs and self-efficacy on pain and physical functioning at discharge in patients with acute and chronic LBP. Methods: Baseline and discharge data from 418 participants with acute or chronic LBP were analyzed. Mediation analyses on discharge functional status and pain intensity were conducted with acute and chronic LBP status as the predictor, and changes in fear-avoidance beliefs and/or self-efficacy from baseline to discharge as the mediator. Results: In multivariable analyses, patients with chronic LBP had lower discharge functional status (beta = -7.4 [95% CI: -10.5; -4.3]) and self-efficacy for physical function (beta = -5.3 [95% CI: -10.2; -0.4]), and higher pain intensity (beta = 0.9 [95% CI: 0.3; 1.5]), but no difference in discharge fear-avoidance beliefs compared to patients with acute LBP. Change in self-efficacy for physical function had a small indirect association (beta = -1.1, [95% bias-corrected CI: -2.5; -0.004]) mediating the relationship between chronic LBP and discharge functional status. Conclusion: Fear-avoidance beliefs were not a mediator of discharge pain or function outcome in patients with chronic LBP. Self-efficacy may be an important mediating factor for discharge function in patients with chronic LBP receiving physical therapy. Level of Evidence: 2b