Kinesiophobia and Clinical Outcomes in People with Chronic Low Back Pain: A Cross-Sectional Study

Background/Objective: Kinesiophobia is a major fear-avoidance concept in chronic low back pain (CLBP); however, its independent contribution to pain, disability, and health-related quality of life (HRQoL) beyond sociodemographic and clinical variables remains unclear. This study aimed to evaluate the associations between kinesiophobia and patient-reported outcomes in adults with chronic low back pain regarding (i) pain intensity, (ii) functional disability, and (iii) HRQoL. Methods: This cross-sectional study included 298 participants with CLBP (average age 38.7 ± 13.2 years; 58.0% female). Kinesiophobia was evaluated using the Tampa Scale of Kinesiophobia (range, 17-68). Outcomes were pain intensity (Numerical Pain Rating Scale; 0-10), functional disability (Roland-Morris Disability Questionnaire; 0-24), and HRQoL (RAND-36; 0-100). Two multivariable linear regression models were used per outcome. Model 1 was adjusted for sex and age, and Model 2 was additionally adjusted for BMI, marital status, education, employment, smoking status, and chronic disease. Hierarchical regression analysis evaluated the incremental variance explained by kinesiophobia (ΔR²) when entered after all covariates. Effects were reported per 10-point increase in Tampa score, with 95% confidence intervals (CI). Results: In the fully adjusted models, higher kinesiophobia was associated with greater pain intensity (B = +1.17 points per 10 Tampa; 95% CI 0.55-1.79, p < 0.001), greater disability (B = +3.24 points; 95% CI 2.05-4.43; p < 0.001), and lower HRQoL (B = -7.98 points; 95% CI -11.1--4.81; p < 0.001). Hierarchical regression analyses showed that kinesiophobia explained additional variance in pain (ΔR² = 0.11), disability (0.12), and HRQoL (0.11), all p < 0.001. Conclusions: In adults with CLBP, kinesiophobia was associated with greater pain intensity, functional disability, and lower HRQoL, accounting for 11-12% of variance in each outcome beyond demographic and clinical covariates. These findings support routine assessment of kinesiophobia and justify longitudinal and interventional studies to determine temporal relationships and treatment effects.