Evaluation of central sensitization and associated factors in systemic lupus erythematosus: a cross-sectional study

To examine the central sensitization and its determinants in systemic lupus erythematosus (SLE) and compare it with psoriatic arthritis (PsA) and healthy controls (HC). We evaluated the sociodemographic and disease-related parameters, and administered to the study groups the Brief Illness Perception Questionnaire (B-IPQ), the Fatigue Severity Scale (FSS), the Jenkins Sleep Evaluation Scale (JSS), the Health Assessment Questionnaire-Disability Index (HAQ-DI), and the Central Sensitization Inventory (CSI). We also measured pain using the visual analog scale (VAS) (0-10 cm). This study included age- and gender-matched SLE (n = 74), PsA (n = 74), and HC (n = 80) groups. The JSS, FSS, and CSI scores were higher in SLE than in HC. Although tender joint count, swollen joint count, VAS, and HAQ-DI scores were statistically higher in the PsA group compared to the SLE group, the central sensitization rates in the two groups were similar (56.7% for SLE and 55.4% for PsA, p = 0.868). CSI was significantly correlated with the number of tender joints, VAS, HAQ-DI, B-IPQ, JSS, and FSS (Spearman's rho ranged from 0.501 to 0.646) in SLE. FSS, JSS, and tender joint count were the most important predictors of CSI. Age, the number of swollen and tender joints, FSS, B-IPQ, and JSS accounted for 74% of the variation in CSI scores in SLE. Psychosocial variables influence central sensitization, which occurs frequently in SLE. SLE and PsA exhibited similar CSI scores but higher than HC. It is beneficial to evaluate and manage central sensitization in SLE patients with fatigue and sleep disorders.