POS0705 BILAG-2004 INDEX ACTIVE DISEASE PREDICTS DEVELOPMENT OF DAMAGE
Authors: C. S. Yee, V. Farewell, M. Akil, P. Lanyon, C. J. Edwards, D. Isenberg, A. Rahman, L. S. Teh, S. Tosounidou, R. Stevens, A. Prabu, B. Griffiths, N. Mchugh, I. N. Bruce, Y. Ahmad, M. Khamashta, C. Gordon
Journal: Annals of the Rheumatic Diseases (2021)

Background: BILAG-2004 Index (BILAG-2004) has undergone construct and criterion validity and is used to assess disease activity in SLE. However, its predictive validity has yet to be established. Objectives: This study was to determine if disease activity according to BILAG-2004 was predictive of development of damage in an inception cohort. Methods: This was a prospective multi-centre longitudinal study in the UK of an inception cohort of SLE patients (recruited within 12 months of achieving 1997 ACR revised criteria for SLE). Data were collected on disease activity (BILAG-2004 and BILAG2004-Pregnancy Index during pregnancy), SLICC/ACR DI (SDI), cumulative drug exposure and death at every visit. Information on cardiovascular risk factors (hypertension, diabetes mellitus, hypercholesterolaemia and smoking status) and antiphospholipid syndrome status were also collected. This study ran from 1st January 2005 to 31st December 2017. Longitudinal analysis using Poisson regression with random effects model was used to determine predictors of development of new damage. Death was not included in the analysis due to small numbers. Results: 273 patients were recruited (91.2% female, 59.3% Caucasian, 17.2% African/Caribbean, 17.2% South Asian) with mean age at recruitment of 38.5 years (SD 14.8). 97.8% had no damage at recruitment (2.2% had SDI score of 1). Median follow-up was 73.4 months (range: 1.8, 153.8) with total follow-up of 1767 patient-years. Prevalence of risk factors during follow-up were: hypertension 23.1%, hypercholesterolaemia 35.5%, diabetes mellitus 5.5%, smoker or ex-smoker 44% and antiphospholipid syndrome 7%. There were 13 deaths and 114 new damage items occurred during follow-up. There were 6674 assessments with disease activity score: 293 assessments with Grade A activity in 95 patients (92.4% had only 1 system with grade A, range: 1 - 4) and 1704 assessments with Grade A or B activity in 239 patients (78.7% had only 1 system with Grade A or B, range: 1 - 5). Univariate analysis showed that gender, cardiovascular risk factors, antiphospholipid syndrome and most drug exposure (except hydroxychloroquine, glucocorticoids, mycophenolate and cyclophosphamide) were not associated with new damage (they were not included in the multivariate analysis). Table 1 summarises multivariate analysis. Similar results were obtained when the disease activity variable was changed to Number of Systems with Grade A per assessment (RR 2.04 with 95% CI: 1.05, 3.94). Analysis using BILAG-2004 systems tally showed that persistent minimal disease was protective of development of damage (RR 0.74 with 95% CI: 0.57, 0.95). Cumulative drug exposure since recruitment for mycophenolate was protective against new damage (RR 0.99 with 95% CI 0.99, 0.99) but not cumulative drug exposure since last visit. Variable Risk Ratio (95% CI) for New Damage Ethnicity Afro-Caribbean 1.21 (0.68, 2.17) South Asian 1.81 (0.97, 3.36) Others 2.37 (0.68, 8.20) Age at diagnosis 1.06 (1.04, 1.08 ) Prior SDI score 0.69 (0.44, 1.08) Constitutional A or B unreliable estimate due to low numbers Mucocutaneous A or B 1.80 (1.04, 3.14 ) Neuropsychiatric A or B 4.68 (1.68, 13.05 ) Musculoskeletal A or B 0.76 (0.33, 1.73) Cardiorespiratory A or B 0.35 (0.05, 2.59) GIT A or B unreliable estimate due to low numbers Ophthalmic A or B unreliable estimate due to low numbers Renal A or B 2.08 (0.99, 4.40) Haematological A or B 4.37 (1.15, 16.65 ) Hydroxychloroquine since last visit (per g ) 0.99 (0.98, 0.99 ) Prednisolone since last visit (per 100mg ) 1.01 (1.00, 1.02 ) Cyclophosphamide since last visit (per g) 1.42 (0.94, 2.14) Conclusion: Active disease (Grade A or B) according to BILAG-2004 index is predictive of development of new damage in SLE patients. References: [1]Yee C. S., et al. The BILAG-2004 systems tally – a novel way of representing the BILAG-2004 index scores longitudinally. Rheumatology (Oxford) 2012; 51[11]: 2099-2105. Acknowledgements: Versus Arthritis and Vifor Pharma Disclosure of Interests: Chee-Seng Yee Consultant of: Bristol Myers Squibb, ImmuPharma, Grant/research support from: Vifor Pharma, Vernon Farewell: None declared, Mohammed Akil: None declared, Peter Lanyon: None declared, Christopher John Edwards Consultant of: Glaxo Smith Kline, Roche, Grant/research support from: Glaxo Smith Kline, Roche, David Isenberg: None declared, Anisur Rahman: None declared, Lee-Suan Teh: None declared, Sofia Tosounidou: None declared, Robert Stevens: None declared, Ahtiveer Prabu: None declared, Bridget Griffiths: None declared, Neil McHugh: None declared, Ian N. Bruce: None declared, Yasmeen Ahmad: None declared, Munther Khamashta: None declared, Caroline Gordon Speakers bureau: UCB, Consultant of: Center for Disease Control, Astra-Zeneca, MGP, Sanofi and UCB