Correlation between Ankylosing Spondylitis Disease Activity Score and MRI Scoring in Patients with Ankylosing Spondylitis: A Cross-sectional Study

Introduction: Ankylosing Spondylitis (AS) is an inflammatory disorder of unknown cause that primarily affects the axial skeleton, peripheral joints, and extra-articular structures. Typically, the condition starts in the second or third decade. Lower back pain lasting longer than three months, morning stiffness lasting more than 30 minutes, relieved by daily activities, are signs of disease onset. Aim: To establish a correlation between disease severity score Ankylosing Spondylitis Disease Activity Score (ASDAS) and Magnetic Resonance Imaging (MRI) scoring in patients with AS. Materials and Methods: This cross-sectional study was conducted on 66 patients attending the Medicine Emergency/ Outpatient Department (OPD)/ward of ESIPGIMSR and ESI Hospital, Basaidarapur, New Delhi, India, who were diagonsed with AS based on the modified New York Criteria. Clinical assessments included ASDAS based on Erythrocyte Sedimentation Rate (ESR) and C-reactive Protein (CRP), while MRI disease activity scores were determined using the Spondyloarthritis Research Consortium of Canada (SPARCC) MRI scoring. The sample size was calculated with a coefficient limit of 10% and a confidence level of 95%. Data analysis was performed using Statistical Packages for Social Sciences (SPSS) version 21.0, a widely used statistical computing and graphics tool. Pearson's correlation coefficients were computed to explore relationships between variables, including age, disease duration, ASDAS-ESR, and MRI changes. Results: In present study, a total of 66 patients were included, out of which 51 (77.3%) were males and 15 (22.7%) were females. The age group of patients included in present study was 33 years to 44 years with a mean of 37.96 years. In present study, the disease duration ranged from a minimum of two years to a maximum of 10 years with a mean of 5.4 years. The mean ASDAS CRP was 3.687 (minimum-2.80, maximum-4.60), and the disease activity as assessed by MRI score (SPARCC) had a minimum value of 8.85 and a maximum value of 26.2 with a mean of 16.359. In present study, the X-ray grading of sacroiliitis revealed that 19.7% of the subjects were classified as Grade-2, 60.6% as Grade-3, and 19.7% as Grade-4. Conclusion: The clinical disease activity index may not always reflect active inflammation, which is detectable by MRI. Incorporating MRI into diagnostic and treatment strategies for AS is crucial for the accurate assessment of disease severity and better patient outcomes.