Predictors of treatment response and drug continuation in 842 patients with ankylosing spondylitis treated with anti-tumour necrosis factor: results from 8 years' surveillance in the Danish nationwide DANBIO registry

• Published in: Annals of the rheumatic diseases Vol. 69; no. 11; pp. 2002 - 2008
• Main Authors: Glintborg, Bente, Østergaard, Mikkel, Krogh, Niels Steen, Dreyer, Lene, Kristensen, Hanne Lene, Hetland, Merete Lund
• Format: Journal Article
• Language: English
• Published: London BMJ Publishing Group Ltd and European League Against Rheumatism 01.11.2010; BMJ Publishing Group; BMJ Publishing Group LTD
• Subjects: Adult; Age; Antirheumatic Agents - therapeutic use; Biological and medical sciences; Biological products; Clinical trials; Denmark; Diseases of the osteoarticular system; Diseases of the spine; Drug Administration Schedule; Epidemiologic Methods; Female; Gangrene; Humans; Immunosuppressive Agents - therapeutic use; Inflammatory joint diseases; Male; Medical sciences; Middle Aged; Patient Compliance - statistics & numerical data; Prognosis; Registration; Rheumatic diseases; Rheumatoid arthritis; Spondylitis, Ankylosing - drug therapy; Studies; Treatment Outcome; Tumor Necrosis Factor-alpha - antagonists & inhibitors; Tumor necrosis factor-TNF; Womens health; Denmark; Human; Diseases of the osteoarticular system; Rheumatology; Inflammatory joint disease; Spine disease; Spondylarthropathy; Chronic; Treatment; Surveillance; Tumor necrosis factor; Danish; Predictive factor; Ankylosing spondylitis
• DOI: 10.1136/ard.2009.124446
• ISSN: 0003-4967

Objectives To use prospectively registered data from the Danish nationwide rheumatological database (DANBIO) to describe disease activity, clinical response, treatment duration and predictors of drug survival (ie, number of days individual patients maintained treatment) and clinical response among patients with ankylosing spondylitis (AS) receiving their first treatment series with a tumour necrosis factor α (TNFα) inhibitor. Methods 842 TNFα inhibitor naive patients with AS were identified in DANBIO. Clinical response, drug survival and predictors thereof were investigated. ‘Clinical response’ was defined as a 50% or 20 mm reduction in Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) within 6 months compared with baseline. Achievement of a BASDAI <40 mm within 6 months was used as a second response parameter. Results 603 patients (72%) were men, disease duration 5 (1–13) years (median (IQR), age 41 (32–50) years. 445 (53%) received infliximab, 247 (29%) adalimumab and 150 (18%) etanercept. Parameters at baseline/1-year follow-up were: C-reactive protein (CRP): 14 (7–27)/5 (2–10) mg/l, BASDAI 59 (44–72)/21 (8–39) mm, Bath Ankylosing Spondylitis Functional Index (BASFI) 50 (34–67)/24 (9–45) mm, Bath Ankylosing Spondylitis Metrology Index 40 (20–50)/20 (10–40) mm. Within 6 months, 407/644 patients (63%) achieved a clinical response. Median drug survival was 4.3 years. One- and 2-year survival rates were 74% and 63%, respectively. Baseline characteristics associated with longer drug survival were male gender, CRP >14 mg/l and low visual analogue scale fatigue (Cox regression analysis). Age, TNFα inhibitor and methotrexate use were insignificant. CRP >14 mg/l, lower BASFI and younger age at baseline was associated with clinical response and achievement of a BASDAI <40 mm (logistic regression analysis). Conclusion TNFα inhibitors provide a rapid and sustained decrease of disease activity among patients with AS in clinical practice. Factors associated with continued treatment, clinical response and achievement of a BASDAI <40 mm were identified.