Canadian researchers demonstrated that a score greater than 20 on the European League Against Rheumatism and the American College of Rheumatology (EULAR/ACR) Classification Criteria for systemic lupus erythematosus (SLE) is an indicator of the accrual of damage and of mortality among patients with SLE.

Laura Patricia Whitall Garcia, MD, from the University of Toronto and the University Health Network in Toronto, Canada, presented these findings at the American College of Rheumatology Convergence 2021.

“Given that disease activity is associated with damage accrual and mortality, we aimed to determine the ability of a EULAR/ACR score ≥20 to predict these long-term outcomes,” Dr Garcia explained.

The investigators recruited 867 patients during the first 12 months after their diagnosis with SLE, and calculated each patient’s EULAR/ACR score from baseline results of clinical and laboratory tests obtained during the first 2 visits. These patients were then divided in groups, those with scores greater than 20 and those with scores below 20 on the EULAR/ACR criteria.

To determine whether a EULAR/ACR ≥20 was predictive of damage accrual and mortality, the researchers assessed “time to first damage accrual, defined as any increase in the SLICC/ACR Damage Index (SDI), and time to death within the first 10 years after SLE diagnosis, analyzed using Kaplan Meier survival curves." 

“For damage accrual, death within the 10 years was used as competing risk. Multivariable Cox Proportional regressions was performed to calculate the risk,” noted study authors. The investigators also calculated a mean SDI score at the 10^th year of follow-up.

“The proportion of patients who accrued damage within the first 10 years and the mean SDI at 10 years were significantly higher in the group of ≥20,” the authors wrote. When looking at the specific domains in SDI, the group with a score ≥20 at 10 years of follow-up had significantly more renal damage and a higher percentage of diabetes.”

After adjusting for age and ethnicity, multivariable regression analysis showed that a score ≥ 20 “continued to significantly predict damage accrual, HR 1.28 (1.04-1.57), P = .02. When we excluded patients who had damage at enrollment the results were similar,” the authors noted.

During the first 10 years of follow-up, 68 patients (7.8%) died. “Individuals in the ≥20 group had twice the probability of dying compared to patients with the lower score; the hazard ratios with significant p values confirmed this finding,” the authors wrote, concluding, “A EULAR/ACR score ≥20 is an indicator of damage accrual and mortality in SLE.”

—Rebecca Mashaw

Reference:
Whittall-Garcia L, Gladman D, Urowitz M, Su J, ZTouma Z, Johnson S. The New EULAR/ ACR 2019 SLE classification criteria: a predictor of long-term outcomes. Presented at: American College of Rheumatology Convergence 2021; November 5-9, 2021; virtual. Abstract 0348.