Uso del índice tobillo-brazo en la reclasificación del riesgo vascular en pacientes con infección VIH / Ankle-brachial index in the assessment of cardiovascular risk among HIV infected patients

Background: Vascular risk is an important cause of morbidity and mortality in HIV infected patients. Aim: To study the value of the ankle-brachial index (ABI) in vascular risk stratification in a cohort of people with HIV infection. Patients and Methods: Vascular risk was calculated in all the patients that agreed to participate in the study and clinical reports were reviewed retrospectively. Ten year risk of fatal myocardial infarction was calculated according to Framingham equation, National Cholesterol Education Program (NCEP) III and Systematic Coronary Risk Evaluation (SCORE) project score. ABI was calculated measuring resting systolic blood pressure at the ankle, that was compared with the systolic brachial pressure. The ratio of the two pressures defined ABI, that was considered abnormal if it was d" 0.9 or e" 1.3. Results: A total of 231 HIV infected patients aged 23 to 82 years (80 percent males) were enrolled. Ten years risk according to Framingham equation was 8.4 percent, 95 percent confidence intervals (CI): 7.54-9.15 and according to SCORE scale was 0.8 percent, 95 percent CI: 0.62-1.01. According to NCEP III 9 percent of patients had a high or very high cardiovascular risk. Median ABI was 1.17 (95 percent CI intervals: 1.16-1.19) and 58 patients (25 percent) had an abnormal value. Using ABI results, approximately 20 percent of patients were re-classified as having a high vascular risk. Conclusions: ABI identified approximately 20 percent of this cohort of HIV infected subjects as having high vascular risk.