Adjusted Global Antiphospholipid Syndrome Score Is Associated with End-Stage Kidney Disease in Patients with ANCA-Associated Vasculitis: A Single-Centre Pilot Study

Abstract

Purpose: The adjusted Global Antiphospholipid Syndrome (APS) Score (aGAPSS) was developed for assessing the probability of thrombotic events in APS patients. This study investigated whether the aGAPSS at diagnosis was associated with poor outcomes during follow-up in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV).

Materials and methods: This study included 170 AAV patients who had the results of APS-related antibodies at diagnosis but were not diagnosed with APS. All-cause mortality, end-stage kidney disease (ESKD), cerebrovascular accident, and acute coronary syndrome were considered poor AAV outcomes. The aGAPSS comprises five items, with 5, 4, 4, 3, and 1 points assigned to anticardiolipin antibodies, anti-β2-glycoprotein 1 antibodies, lupus anticoagulants, hyperlipidaemia, and arterial hypertension at AAV diagnosis, respectively.

Results: The median age of the 170 patients [93 microscopic polyangiitis (MPA), 44 granulomatosis with polyangiitis (GPA), and 33 eosinophilic GPA (EGPA)] was 63.0 years. The optimal cut-off of the aGAPSS at diagnosis for ESKD during follow-up was set as two using the receiver operating characteristic curve. AAV patients with an aGAPSS ≥2 at diagnosis exhibited a significantly reduced ESKD-free survival rate compared to those with an aGAPSS <2 at diagnosis (p=0.045). Additionally, MPA and GPA patients, excluding EGPA patients for whom the median aGAPSS at diagnosis was close to 0, also showed similar patterns to the results among the 170 patients with AAV (p=0.021).

Conclusion: This study is the first to demonstrate that the aGAPSS at diagnosis was significantly associated with ESKD during follow-up in AAV patients without APS.