This study, performed to assess the prevalence and clinical implications of metabolic syndrome (MetS) in patients with primary antiphospholipid syndrome (pAPS), involved 71 patients with pAPS and 73 age-matched controls. 33.8% of patients with pAPS in this study also had MetS, and these patients had a higher risk of arterial events and cardiovascular risk factors than patients with pAPS alone. The authors conclude that co-existant MetS might exacerbate endothelial abnormalities of pAPS.