Association Between Psychosocial Parameters and Response to Chiropractic Care Among Older Adults With Chronic Low Back Pain: Secondary Analysis of a Randomized Clinical Trial

Objectives: The purpose of this study was to determine whether baseline self-efficacy, fear of pain with movement (kinesiophobia), or change in either were associated with clinically important improvement in disability among older adults with chronic low back pain after 12 weeks of chiropractic spinal manipulation (CSM) and exercise. Methods: This secondary analysis used randomized trial data from community-dwelling adults aged 65 years or older with chronic spinal disability who received non-pharmacological treatment of CSM and exercise. Those with >= 30% reduction in the Oswestry Disability Index (ODI) after 12 weeks of treatment were considered responders to care. Psychosocial measures included the Pain Self-Efficacy Questionnaire (PSEQ) and the Tampa Scale of Kinesiophobia (TSK). Logistic regression-assessed associations were between psychosocial, demographic, and low back predictors and 30% ODI improvement. Results: There were 176 community-dwelling older adults included in this analysis. Mean age was 71 years, 59.7% were women; 176 (96.7%) had complete data. Baseline disability (ODI = 26.1 +/- 9.3) and back pain (5.0 +/- 1.9, 0-10 scale) were moderate. Baseline PSEQ reflected higher self-efficacy (47.7 +/- 7.8, 0-60 scale) with minimal kinesiophobia (TSK 34.3 +/- 5.2, 17-68 scale). Seventy-two (40.9%) achieved 30% reduction in ODI (mean -5.4 +/- 7.9) after 12 weeks of treatment. Mean self-efficacy improvement was clinically important (2.5 +/- 6.5 points); kinesiophobia (-2.7 +/- 4.4 points) and LBP (-1.6 points) also improved. Baseline PSEQ and percent improvement in PSEQ and TSK were associated with response to treatment in univariate regression analyses but not in multiple regression models that included low back predictors. LBP duration > 4 years negatively impacted recovery. Conclusions: Among this sample of older adults who received chiropractic manipulation and exercise, baseline self -efficacy and improvements in self-efficacy and kinesiophobia were individually associated with clinically important reductions in disability post-intervention, although not in adjusted models when LBP duration was included. (J Manipulative Physiol Ther 2021;44;675-682)