Central Sensitization in Spondyloarthritis: The Crossroads between Disease Activity, Health-related Quality of Life and Fibromyalgia

Objective: To assess central sensitization in young patients with spondyloarthritis (SpA) and to study the associated factors with higher central sensitization scores. Methods: This was a cross-sectional study including patients with SpA (ASAS criteria) aged less than 50 years. For all patients, we collected the sociodemographic and disease characteristics data. Central sensitization was assessed using a validated tool: The Central Sensitization inventory (CSI). Pain status, fibromyalgia, quality of life, anxiety and depression were screened by the Brief pain inventory, the Fibromyalgia rapid screening tool (FiRST), the ASQoL, and the Hospital anxiety and depression scale (HAD) anxiety and depression. Univariable and multivariable linear regression analyses were performed to achieve our objective. Results: Seventy-two patients were enrolled (65,2% males). The median age was 39 (28,25-46) years. Median BASDAI and ASDAS-CRP scores were 3 (2.1 - 4.7) and 2.7 (1.9 - 3.48), respectively. The median value of the CSI score was 15 (6,25-33,75); a CSI≥40 was noted in 15.3% of patients. Depression, anxiety scores, fibromyalgia and impaired QoL were screened in 11%, 9,7%, 9,7%, and 44,4%, respectively. CSI≥40 was positively correlated with ASQoL, FiRST, HAD anxiety, HAD depression and the 5 categories of pain interference (mood, regular work, relationships, sleep and enjoyment of life). Multivariate analysis identified a predictive model which included the combination of FiRST, BASDAI and ASQoL. First was the strongest predictive factor of a higher central sensitization. Conclusion: CS is frequent among SpA patients and should be looked for in order to improve QoL.