To investigate the atherosclerosis hypothesis in primary antiphospholipid syndrome (PAPS).
The intima media thickness (IMT) of carotid arteries and other cardiovascular risk factors was measured in 20 patients with PAPS (mean (SD) age 35 (12) years) and in 20 controls matched for age and sex (34 (12) years).
The frequency of smoking, hypertension, and dyslipidaemia was similar in the two groups, but plasma homocysteine was higher in patients with PAPS (mean (SD) 11.9 (6.2) v 8.2 (3.4) micromol/l, p = 0.037). The IMT was slightly greater in patients with PAPS than in controls at the carotid bifurcation (mean (SD) 0.61 (0.24) v 0.48 (0.09) mm, p = 0.04) and internal carotid artery (0.52 (0.22) v 0.40 (0.08), p = 0.01). These differences were more evident in patients aged >40 years than in those aged <30 years at the carotid bifurcation (0.76 (0.25) v 0.55 (0.06), p = 0.0007) and internal carotid artery (0.63 (0.25) v 0.45 (0.09), p = 0.02); no differences were seen in the younger age group compared with controls.
Atherosclerosis is a possibility in patients with PAPS in their fourth decade of life or older.