Biopsychosocial profile in individuals with chronic low back pain and high central sensitization symptoms: a cross-sectional comparative study.

BACKGROUND: Chronic low back pain (CLBP) is a heterogeneous condition, and some individuals may exhibit high levels of central sensitization (CS) symptoms. PURPOSE: This study aimed to compare pain, physical and cognitive functions, circadian rhythm characteristics, and psychosocial factors in individuals with CLBP with high and low CS symptoms, and asymptomatic controls. METHODS: This study included 45 participants. Individuals with CLBP were classified based on the Central Sensitization Inventory (CSI) scores: high-CSI and low-CSI.The high-CSI [age:45(37-54) years], low-CSI [age:50(39-59) years], and asymptomatic control group [age:44(28-52) years] each consisted of 15 individuals. Visual Analog Scale for pain intensity; an algometer for pressure pain threshold (PPT); an algometer and an ischemic cuff for conditioned pain modulation (CPM); Oswestry Disability Index for disability; Montreal Cognitive Assessment for cognitive function; Morningness-Eveningness Questionnaire for chronotype; Pittsburgh Sleep Quality Index for sleep quality; Epworth Sleepiness Scale for daytime sleepiness; Hospital Anxiety and Depression Scale for anxiety and depression; and Pain Self-Efficacy Questionnaire for pain self-efficacy were used. Independent samplest-test, Mann-Whitney U test, one-way ANOVA, Kruskal-Wallis test, and Fisher exact test were used for statistical analyses. RESULTS: Compared with the low-CSI group, the high-CSI group had higher rest, activity, and night pain intensity (p = .025, p = .004, and p = .012, respectively), lower PPTs at the thumbnail and low back (p = .043 and p = .012, respectively), lower CPM at the thumbnail (p = .035), higher physical disability (p = .032), and greater sleep disturbance (p = .001). Compared with the asymptomatic control group, the high-CSI group had shorter sleep duration (p = .007), greater sleep disturbance (p = .001), and poorer sleep quality (p = .009). CONCLUSION: Individuals with CLBP and high CS symptoms exhibit higher pain intensity, lower PPTs, reduced CPM, greater physical disability, and poorer sleep. By emphasizing the heterogeneity of CLBP and the clinical relevance of central sensitization symptoms, this study supports individualized and mechanism-informed rehabilitation planning.