The Relationship Between Pan Immune-Inflammation Value and Disease Activity in Ankylosing Spondylitis

Objectives: Ankylosing spondylitis (AS) is a chronic inflammatory disease affecting the axial skeleton and peripheral joints, causing pain, stiffness, and reduced function. Monitoring disease activity is crucial, but no specific laboratory markers reflect disease activity in AS. This study evaluated the relationship between pan immune-inflammation value (PIIV) and disease activity in AS. Materials and Methods: This study included patients with AS fulfilling the modified New York classification criteria. Disease activity was assessed using the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and the Ankylosing Spondylitis Disease Activity Score with C-reactive protein (ASDAS-CRP). Data included demographic, clinical, treatment, and laboratory variables, including C-reactive protein (CRP), erythrocyte sedimentation rate, blood counts, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio (PLR), monocyte-to-lymphocyte ratio, systemic immune-inflammation index (SII), and PIIV. Results: Of 64 patients (female/male: 22/42), 38 (59.4%) had active disease according to BASDAI. The active group showed higher PIIV, ASDAS-CRP, platelet count, PLR, and SII, and lower hemoglobin than the inactive group. PIIV correlated with BASDAI, ASDAS-CRP, and inflammatory markers including CRP, erythrocyte sedimentation rate, neutrophil, platelet, and monocyte counts, neutrophil-to-lymphocyte ratio, PLR, monocyte-to-lymphocyte ratio, and SII. Conclusion: PIIV was significantly higher in active AS and correlated with disease activity and inflammatory markers. It may support disease activity assessment in AS.