Abstract

Ankylosing Spondylitis (AS) is a long-term inflammatory rheumatic condition that mainly impacts axial regions, including the spine and sacroiliac joints. Typical symptoms consist of back discomfort, rigidity, and anterior uveitis, all of which are strongly linked to inflammatory mechanisms. Identifying reliable biomarkers for inflammation is essential for effectively monitoring the disease and determining clinical outcomes. This research seeks to assess the connection between Disease Activity (DA) and systemic inflammation markers in AS. A retrospective study was performed with 121 patients with AS and 90 participants with normal physiological and physical examination findings, who were observed at the Physical Medicine and Rehabilitation Clinic from January 1, 2023, to May 1, 2024. Demographic information and laboratory findings, including inflammatory markers, were collected. DA scores were recorded. Values for neutrophils, monocytes, lymphocytes, and platelets from hematological parameters, along with the derived indices of Neutrophil-to-Lymphocyte Ratio (NLR), Monocyte-to-Lymphocyte Ratio (MLR), Platelet-to-Lymphocyte Ratio (PLR), Systemic Immune Inflammation Index (SII), Systemic Inflammation Response Index (SIRI), and Systemic Inflammation Aggregate Index (SIAI), were documented. No significant age difference was observed among the group of patients and the group of controls (p=0.812). A notable distinction was found between the two groups regarding monocyte levels (p=0.047). According to the Ankylosing Spondylitis Disease Activity Score (ASDAS) classification, significant variations in C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) levels were detected between the high DA and low DA groups (p0.05). In this study, traditional inflammatory biomarkers (CRP and ESR) were associated with DA, while indices calculated from hematological parameters did not show significant associations. Additional research is required to examine the clinical relevance of these systemic inflammation indices in the assessment of AS activity.

Key words: Ankylosing spondylitis, Systemic Immune Inflammation Index, disease activity