Prospective Study of Patients with Inflammatory Back Pain, Clinical Characteristics and Treatment Response in Ankylosing Spondylitis in Two Centers of Rheumatology in South India

Introduction: Ankylosing spondylitis is inflammatory arthritis affecting the spine and peripheral joints more commonly in men of 15 years to 40 years of age and is a part of the spectrum of diseases called spondyloarthropathy. Psoriasis, uveitis, ulcerative colitis, and inflammatory bowel disease form part of the systemic manifestations. There exists a long delay between the onset of inflammatory back pain and being diagnosed with ankylosing spondylitis. Methodology: We set out to study the clinical profile, diagnosis, and management of patients with spondyloarthritis (SpA) prospectively and follow-up over 2 years period. All patients who had inflammatory back pain and diagnosed to have SpA were included in this prospective study in two different centers of Rheumatology. Clinical characteristics, magnetic resonance imaging (MRI)-spine and sacroiliac joints, disease activity using Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Functional Index (BASFI), and early treatment response were assessed. Other investigations including bloods, X-rays, and screening for biologics were done as and when indicated. We used both synthetic Disease-Modifying AntiRheumatic Drugs (DMARDS) and biosimilars as per the British Society of Rheumatology guidelines and patient choice. Patients were reviewed every 3 months for 1-2 years. The response to treatment was assessed and compared with other studies. Results: Forty -two patients were studied in this 2 years period (15 patients out of 57 lost to follow up). All patients had the diagnosis of ankylosing spondylitis as per Assessment of Spondylo Arthritis international Society (ASAS Score) criteria and MRI evidence of sacroiliitis and 22 patients had peripheral synovitis. HLA-B27 was positive in 11/19 patients. Eleven patients had been on anti-Tumor Necrosis Factor (TNF) drugs and 26 patients were on DMARDs. At the end of 24 weeks, disease activity indices including BASDAI and BASFI were low in remission and statistically significant. At the end of 2 years, most of them were in remission and 81% were continuing to work and maintain productivity. Patients who underwent treatment with biosimilar TNFs showed a significant reduction in disease activity and achieved remission earlier, as evidenced by BASDAI and BASFI scores, compared to others who were on DMARDS and supportive therapy. The usage of DMARDS was more than biosimilar drugs as they are expensive. Conclusion: This study shows the real-world data on the diagnosis and management of patients with ankylosing spondylitis, achieving remission, and maintaining the work-life balance. Early diagnosis with MRI and appropriate intervention with DMARDS are the important factors in this study.