Ankle-brachial index and arterial vascular events in systemic lupus erythematosus patients: a 5-year prospective cohort.

Objectives: To determine the potential predictive value in patients with systemic lupus erythematous of the ankle-brachial index (ABI) for the occurrence of arterial vascular events.

Methods: 216 lupus patients from a prospective clinical cohort were evaluated using the ABI at the start of the study and then followed up for 5 years. Abnormal ABI was defined as an index ≤0.9 or >1.4. Several potential vascular risk factors were also evaluated. Arterial vascular events (AVE): coronary events, cerebrovascular events, peripheral arterial disease and death related to vascular disease. Survival analysis was performed using a competitive risk regression approach, considering non-vascular death as a competitive event.

Results: 18 arterial events and 14 deaths were identified. In the competitive risk regression analysis, independent predictors of higher risk were identified: family history of early AVE [subdistribution hazard ratio (SHR) 5.44, 95% confidence interval (CI) 1.69-17.50, p=0.004)], cumulative prednisone (grams) (SHR 1.01, 95% CI 1.01-1.03, p=0.007) and a personal history of arterial thrombosis (SHR 5.44, 95% CI 1.45-14.59, p=0.004). Female gender was a protective factor (SHR 0.22, 95% CI 0.07-0.77, p=0.017). A statistical trend was detected with abnormal ABI (SHR 2.65, 95% CI 0.86-8.14, p=0.089).

Conclusions: Male gender, exposure to high cumulative doses of prednisone, family history of early arterial vascular disease and occurrence of previous arterial thrombosis are independent risk predictors of arterial vascular events in patients with systemic lupus erythematosus. Abnormal ABI may be related to high risk for arterial vascular events.