Autonomic Dysfunction, Psychosocial Factors, and Pain Sensitivity in Persistent Spinal Pain: A Systematic Review

Background/Objectives: Persistent spinal pain, including chronic low back pain (CLBP), chronic neck pain, and whiplash-associated disorders (WAD), is a highly prevalent musculoskeletal condition. The recent literature emphasizes a biopsychosocial framework, acknowledging that altered pain processing, psychological impairments, and autonomic nervous system dysfunction are associated with chronic pain. However, the concurrent within-sample relationships between these domains remain poorly understood and inconsistently reported. To systematically evaluate the associations among physiological autonomic measures, validated psychosocial scales, and pressure algometry in adults with persistent spinal pain. Methods: A systematic search was conducted in accordance with PRISMA guidelines. A systematic search was conducted across four electronic databases (PubMed, Web of Science, Scopus, and CINAHL) for studies evaluating all three domains within the same cohort. The search was restricted to peer-reviewed articles published in English and Spanish. Two independent blinded reviewers screened and selected the studies. Eligible studies evaluated within-sample relationships across three domains: autonomic indices (e.g., heart rate variability (HRV) and blood pressure (BP)), psychosocial factors (e.g., kinesiophobia and pain catastrophizing), and quantitative sensory testing (QST) (e.g., pressure pain threshold (PPTs)). Quality assessment was performed using the National Institutes of Health (NIH) tools. Due to significant methodological heterogeneity, the data were synthesized narratively. Results: Six studies fulfilled the eligibility criteria. The narrative synthesis revealed a preliminary pattern showing that objective functional outcomes and experimental pain processing tend to show closer associations with autonomic proxies (such as heart rate variability), whereas subjective clinical outcomes (such as perceived disability) are more consistently linked to psychosocial factors (such as kinesiophobia and catastrophizing). Conclusions: These preliminary findings suggest potentially distinct domain-specific associations rather than a uniform pathophysiological mechanism. Future specialized research and research-informed practice should incorporate multimodal assessments to better characterize individual patient profiles.