SAT0217 PERFORMANCE OF ACR/EULAR 2019, SLICC 2012 AND ACR 1997 CLASSIFICATION CRITERIA IN A COHORT OF SYSTEMIC LUPUS ERYTHEMATOSUS PATIENTS WITH LONGSTANDING DISEASE
Authors: D. Lobo Prat, B. Magallares, I. Castellví, H. Park, P. Moya, I. Gich, A. Laiz, C. Díaz-Torné, A. M. Millán Arciniegas, S. P. Fernandez-Sanchez, H. Corominas
Journal: Annals of the Rheumatic Diseases (2020)

Background: Systemic lupus erythematosus (SLE) is an autoimmune disease with variable clinical features and a complex physiopathology. In 2019, EULAR and ACR have jointly developed new classification criteria with both high sensitivity and specificity. These criteria have the particularity of including the presence of ANA as an obligatory entry criterion and the existence of clinical and immunological domains with weighted scores. Objectives: To evaluate the performance and characteristics of the ACR/EULAR 2019, SLICC 2012 and ACR 1997 classification criteria in a cohort of SLE patients with longstanding disease. Methods: Descriptive observational study that enrolled a cohort of SLE patients with longstanding disease followed in a tertiary level hospital. Demographic and clinical data were gathered along with the fulfillment of classification criteria. The sensitivity of each classification criteria and the statistically significant associations between criteria fulfillment and clinical and immunological data were calculated. Statistical analyses were performed using the Chi2, T-student and ANOVA tests. Statistical significance was assumed in p values &lt;0.05. Results: A total of 79 patients (88.6% women) with a mean age of 51.8±14 years, disease duration of 15.2±11.5 years and SLEDAI of 2.65±2.1 were included. The sensitivity of the different classification criteria was 51.9% for ACR 1997, 87.3% for SLICC 2012 and 86.1% for ACR/EULAR 2019 (Table 1). Table 1. Sensitivity and average scores. ACR/EULAR 2019 SLICC 2012 ACR 1997 Sensitivity (% ) 86.1 87.3 51.9 Average score of patients classified as SLE (± SD ) 18.6±5.8 5.3±1.4 5±0.9 Average score of patients NOT classified as SLE (± SD ) 6.1±2.5 2.8±0.4 2.8±0.8 51.9% of patients met all three classification criteria, 29.1% met SLICC 2012 and ACR/EULAR 2019, 5% only met SLICC 2012 and 3.7% exclusively met ACR/EULAR 2019. 11.4% of patients did not meet any classification criteria and were characterized by having a low SLEDAI (0.6±0.9) and fulfilling only skin domains (alopecia or oral ulcers), antiphospholipid antibodies or hypocomplementemia. Statistically significant associations were found between meeting ACR/EULAR 2019 classification criteria and the presence of low C3 and C4 (p&lt;0.04), DNA (p&lt;0.001), lupus nephritis III-IV (p&lt;0.05) and arthritis (p&lt;0.001), highlighting that all patients with arthritis met these criteria. In the SLICC 2012 evaluation, significant associations were found between meeting these criteria and the presence of arthritis (p&lt;0.01), renal involvement (p&lt;0.04), leukopenia/lymphopenia (p=0.05), DNA (p&lt;0.03) and hypocomplementemia (p=0.02). Fullfilment of ACR 1997 was associated to the presence of malar rash (p&lt;0.001), discoid lupus (p&lt;0.05), photosensitivity (p&lt;0.001) and oral ulcers (p&lt;0.04), as well as arthritis (p&lt;0.001), serositis (p=0.02), renal (p&lt;0.05) and hematologic (p=0.05) involvement. The Kappa concordance coefficient among classification criteria is detailed in Table 2. Table 2. Kappa concordance coefficient. ACR/EULAR 2019 - SLICC 2012 ACR/EULAR 2019 - ACR 1997 SLICC 2012 - ACR 1997 Kappa concordance coefficient 0.61 0.27 0.30 Conclusion: The ACR/EULAR 2019 classification criteria maintain a high sensitivity similar to the SLICC 2012 in SLE patients with longstanding disease, both of which are much higher than ACR 1997. Patients with serological, articular or renal involvement are more likely to meet SLICC 2012 or ACR/EULAR 2019 criteria. It is noteworthy the relevance of dermatological manifestations in ACR1997 classification criteria against the increased weight that a better understanding of SLE physiopathology has provided to analytic and immunological criteria in the subsequent classification criteria. Disclosure of Interests: David Lobo Prat: None declared, Berta Magallares: None declared, Ivan Castellví Consultant of: Boehringer Ingelheim, Actelion, Kern Pharma, Speakers bureau: Boehringer Ingelheim, Actelion, Bristol-Myers Squibb, Roche, HyeSang Park: None declared, Patricia Moya: None declared, Ignasi Gich: None declared, Ana Laiz: None declared, Cesar Díaz-Torné: None declared, Ana Milena Millán Arciniegas: None declared, Susana P. Fernandez-Sanchez: None declared, Hector Corominas: None declared