The 2023 ACR/EULAR antiphospholipid syndrome classification criteria identify patients at high risk of complications

ObjectivesThis study aims to evaluate the utility of the 2023 ACR/EULAR antiphospholipid syndrome (APS) classification criteria in identifying primary APS patients at high risk of complications.MethodsIn this single-center study, primary APS patients were classified according to both the revised Sapporo criteria and the 2023 ACR/EULAR criteria. The risk of complications was assessed using the adjusted Global Antiphospholipid Syndrome Score (aGAPSS).ResultsForty-five patients (73% females, median age 49 years) were included. Thirty-six patients met the 2023 ACR/EULAR criteria, all of whom also fulfilled the revised Sapporo criteria. Additionally, four out of nine patients not meeting the 2023 ACR/EULAR criteria satisfied the revised Sapporo criteria. Agreement rate between the two classification criteria was 91%, with a Cohen's kappa index of 0.66.Patients meeting the 2023 ACR/EULAR criteria had significantly higher aGAPSS scores compared to those who did not (13, 8-13 vs. 3, 0-5; p = 0.005). Furthermore, 55% of patients meeting the 2023 ACR/EULAR criteria were categorized as high risk based on aGAPSS scores, while those not meeting the criteria were predominantly categorized as low risk (77%). Interestingly, patients not meeting the 2023 ACR/EULAR criteria but fulfilling the revised Sapporo criteria had significantly higher aGAPSS scores compared to those not meeting either set of criteria (7, 5-13 vs. 0, 0-1.5; p = 0.015).ResultsForty-five patients (73% females, median age 49 years) were included. Thirty-six patients met the 2023 ACR/EULAR criteria, all of whom also fulfilled the revised Sapporo criteria. Additionally, four out of nine patients not meeting the 2023 ACR/EULAR criteria satisfied the revised Sapporo criteria. Agreement rate between the two classification criteria was 91%, with a Cohen's kappa index of 0.66.Patients meeting the 2023 ACR/EULAR criteria had significantly higher aGAPSS scores compared to those who did not (13, 8-13 vs. 3, 0-5; p = 0.005). Furthermore, 55% of patients meeting the 2023 ACR/EULAR criteria were categorized as high risk based on aGAPSS scores, while those not meeting the criteria were predominantly categorized as low risk (77%). Interestingly, patients not meeting the 2023 ACR/EULAR criteria but fulfilling the revised Sapporo criteria had significantly higher aGAPSS scores compared to those not meeting either set of criteria (7, 5-13 vs. 0, 0-1.5; p = 0.015).ConclusionThe 2023 ACR/EULAR criteria effectively identify primary APS patients at increased risk of complications, as indicated by the aGAPSS score.Key Points center dot Identifying primary APS patients at high risk of complications remains a significant challenge.center dot The 2023 ACR/EULAR criteria show a correlation with the aGAPSS score, exhibiting the highest correlation with laboratory domains and minimal correlation with clinical domains.center dot The 2023 ACR/EULAR classification criteria are effective in identifying primary APS patients at high risk of complications.