Cardiovascular Risk Factors and Antiphospholipid Antibodies in Giant Cell Arteritis-Related Thrombosis.

BACKGROUND/AIMS: Giant cell arteritis (GCA), a large-vessel vasculitis, is associated with increased risks of venous and arterial thrombotic events, such as visual ischemia, pulmonary embolism, and ischemic stroke. Traditional cardiovascular risk factors, such as diabetes mellitus, hypertension (HTN), and hyperlipidemia (HLD), might contribute to these events. While antiphospholipid antibodies (aPLs) are sometimes present, their role in GCA-related thrombosis remains uncertain. MATERIALS AND METHODS: Seventy-five patients with biopsy-confirmed GCA were recruited, and 1-time blood samples were collected to assess for aPL. Cardiovascular risk factors (e.g., HTN, diabetes, HLD, and atrial fibrillation) at study visit and thrombotic events (pulmonary embolism, deep vein thrombosis, transient ischemic attack, stroke, and visual ischemia) throughout follow-up were abstracted from medical records. Chi-square tests and Cox models were used to evaluate associations between aPLs and these events and their risk factors. RESULTS: In this cohort of 75 GCA patients, 25 (33%) had at least 1 positive aPL, with anticardiolipin IgM being the most common. Visual ischemia occurred in 19 (25%) patients. There was no significant association between visual ischemia and cardiovascular risk factors, but there was a significant association between anti-beta-2 glycoprotein I IgM and visual ischemia (P = .048) as well as between aB2GPI IgG and the development of PE/DVT (P = .0035). Overall, 16 experienced a composite thrombotic event, with only aB2GPI IgG associated with higher ischemic event rates. CONCLUSION: Although aPL might be prevalent among GCA, there were minimal associations between aPL isotypes and GCA thrombotic events. Further studies are needed to confirm aPL prevalence in GCA and explore anticoagulation's potential role in patients with visual ischemia and positive aPL. Cite this article as: Hasbani GE, Crowson C, Snyder M, Warrington K, Koster M. Cardiovascular risk factors and antiphospholipid antibodies in giant cell arteritis-related thrombosis. Arch Rheumatol. 2025;40(4):422-426.