Lightning Podiums: Smorgasboard - Room 802B

Presented by: K. Sundararajan

Author(s):

K. Sundararajan(1), Y.R. Rampersaud(1,2),(3), A.V. Perruccio(1,4)

(1) Krembil Research Institute, University Health Network, Arthritis Program, Toronto, ON, Canada
(2) University Health Network, Division of Orthopaedic Surgery, Toronto, ON, Canada
(3) Krembil Neuroscience Centre, Toronto, ON, Canada
(4) University of Toronto, Dalla Lana School of Public Health, Toronto, ON, Canada

Abstract

Background: Low back pain (LBP) often has variable outcomes, even among patients with similar clinical presentation. Self-efficacy, a psychological construct representing the strength of one's belief that they are capable of reaching a desired goal, may play a role as a potential driver of LBP outcomes. Little is known about its predictors and how it affects low back pain and disability. This study sought to identify factors predicting self-efficacy and mediators of its effects in non-surgical LBP patients.

Methods: Patients in a LBP self-management education program (the Interprofessional Spine Assessment and Education Clinics) completed questionnaires before and after assessment. Self-efficacy, patient characteristics, treatment expectations, and STarT-Back risk of chronicity were collected pre-assessment. Self-efficacy was measured using the Self-Efficacy for Managing Chronic Disease scale, a validated instrument measuring patient self-efficacy for self-management of chronic conditions. Disability was measured using the Oswestry Disability Index, which was collected pre- and 6 months post-assessment. Path analysis, a method for testing how well observed data fits a hypothesized causal model, was used to simultaneously identify self-efficacy predictors and test treatment expectations as a potential mediator of self-efficacy's effect on 6-month disability.

Results: 605 patients assessed between 2012 and 2016 were included in this analysis. The sample was 56% female and mean (± SD) age was 52 ± 16 years. Mean disability was 34 ± 18 at baseline and 24 ± 19 at six months (0-100 scale, lower is better). Mean self-efficacy score was 6.7±2.0 (1-10 scale, higher is better). Self-efficacy was found to be a strong independent predictor of disability outcome: adjusting for age, gender, leg- versus back-dominant pain, chronicity risk, and baseline disability, each unit increase in self-efficacy score predicted a 1.5-unit decrease in 6-month disability score (p< 0.001). The estimated path model had good fit (chi-square=8.115, p=0.42, RMSEA(95% CI)=0.005 (0.00, 0.05)) and explained 40% of the variation in 6-month disability. Increased self-efficacy was predicted by better baseline disability and lower chronicity risk. In addition to self-efficacy and treatment expectations, 6-month disability was predicted by worse baseline disability and chronicity risk, as well as older age and female gender. There was evidence that the self-efficacy's effect on disability outcome is partially mediated by treatment expectations, which accounted for 12% of the total effect of self-efficacy (p=0.04).

Conclusions: Self-efficacy is an independent predictor of outcome in self-management of LBP. This relationship is partly explained by self-efficacy's effect on treatment expectations. Both self-efficacy and expectations are potentially modifiable with appropriate support. LBP patients with worse baseline disability and chronicity risk may particularly benefit from targeted approaches to modify self-efficacy.