Current Status of Biological Treatment in Ankylosing Spondylitis Patients and Some Related Factors

BACKGROUND: Axial spondyloarthritis (axSpA) is a potentially disabling inflammatory arthritis of the spine, usually presenting as chronic back pain typically before the age of 45 years. It is often associated with one or more articular features, including synovitis, enthesitis, and dactylitis. It may also be associated with several non-articular features; these include uveitis, psoriasis, and inflammatory bowel diseases1. OBJECTIVE: The aim of this article is to describe the status of using biological drugs and some related factors in treating ankylosing spondylitis in Vietnam. METHODS: A joint prospective and retrospective cross-sectional descriptive study was conducted on 161 ankylosing spondylitis patients treated with biological drugs at the Centre for Rheumatology between January 2018 and July 2021. Data were collected at the first dose and after 3, 6, 12, 24, and 36 months, including general characteristics, clinical and para-clinical features, drug use status, and related factors. RESULTS: Of the 161 patients, 86.3% were male, with a mean age of 31.1 ± 11.6 years and a mean disease duration of 7.6 ± 6.6 years. Most patients were started on biologics at stage II (46.6%) or III (28.6%). Moreover, 68.9% had active disease based on the Bath Ankylosing Spondylitis Disease Activity Index. The most commonly prescribed first-line therapy was anti-tumor necrosis factor (69.6%), with infliximab the most frequently prescribed drug (44.7%). The rate of biological drug treatment decreased gradually from 100% at the start to 77% after one year and 39.1% after three years. Moreover, 74% of patients changed drugs due to non-response, and 50% discontinued treatment for economic reasons. Age was associated with treatment adherence, and drug change rates were higher in female patients and patients with active disease. Age was significantly associated with drug discontinuation (p < 0.05). CONCLUSION: Infliximab was the most commonly prescribed first-line drug. The rate of biological therapy gradually decreased after three years. Most patients changed drugs due to non-response, and many discontinued the drugs for economic reasons. Among the individual and clinical factors, age was associated with treatment adherence.