Our purpose was to examine prospectively the relationship between systemic hypertension and vascular events in patients with SLE. SLE patients followed in the University of Toronto Lupus Clinic presenting between 1980 and 1988 and within one year of their diagnosis of SLE were identified. Standard definitions were used for hypertension and for all vascular events (MI, angina, CVA, PVD). The presence of traditional CAD risk factors, along with disease- and therapy-related risk factors for the development of vascular disease, were compared in the hypertensive and normotensive group. A multivariate logistic regression was performed to determine the best predictor of a vascular event. One hundred and fifty patients were identified in our inception cohort [75 hypertensive (50%) and 75 (50%) normotensive]. Seventeen hypertensive patients (22.7%) had at least one vascular event as compared to six (8.0%) normotensive patients (p = 0.022). The vascular events included 7 with CAD, 5 with CVA, and 5 with PVD in the hypertensive group while in the normotensive group 3 patients developed CAD, 2 CVA and 1 PVD. Fifteen deaths were recorded in the hypertensive group as compared to eight deaths in the non-hypertensive groups (P = 0.09). The groups were comparable with respect to associated risk factors, except for higher frequency of hypercholesterolemia (P = 0.003), azotemia (P = 0.001) and corticosteroid use (P = 0.038) in the hypertension group. In a multivariate analysis the best predictor of a vascular event was hypercholesterolemia (OR 6.9, 95% CI 2.4-24.8, P < 0.001). We conclude that systemic hypertension is associated with an increased frequency of vascular events in SLE. This is best explained by its association with hypercholesterolemia.