Performance of the 2019 European League Against Rheumatism/American College of Rheumatology classification criteria for systemic lupus erythematosus in a multiethnic Malaysian cohort

AIM: To evaluate the performance of the 2019 European League Against Rheumatism/American College of Rheumatology (EULAR/ACR) classification criteria for systemic lupus erythematosus (SLE) in a multi-ethnic Malaysian cohort and to compare it against the Systemic Lupus International Collaborating Clinics (SLICC) 2012 and ACR 1997 criteria.

METHOD: We conducted a retrospective observational study of 205 patients with a diagnosis of SLE and 100 controls who formed the validation cohort. The sensitivity and specificity of the three classification criteria were evaluated and a further sub-analysis was performed in patients with early disease and among the various ethnicities.

RESULTS: The sensitivities and specificities of the three classification criteria are as follows: EULAR/ACR (90.8%; 94%), SLICC 2012 (96.1%; 94%), and ACR 1997 (82%; 96%). Among patients with early disease, the sensitivity of the SLICC 2012 was higher than that of EULAR/ACR and ACR 1997 (98% vs 94% and 86%); however, the specificity of EULAR/ACR and ACR 1997 were similar (95.2%) and higher than the SLICC 2012 (93.5%). The SLICC 2012 had higher sensitivity than that of the EULAR/ACR among the Malays (94% vs 90%), Chinese (98% vs 90%), and Indians (100% vs 95%). The specificity of the EULAR/ACR and SLICC 2012 were similar in the Malay and Chinese (93.3% each, and 92% vs 94.6%).

CONCLUSION: The EULAR/ACR performed well in our cohort. The EULAR/ACR and SLICC 2012 showed higher sensitivity than the ACR 1997, and the EULAR/ACR showed similar specificity to the ACR 1997 and SLICC 2012 overall, in early disease, and across the different ethnicities.