Abstract 513: Lower Nadir Cd4 T-cell Count is a Strong Predictor of Endothelial Dysfunction in HIV Infected Patients

Background: Nadir CD4 T-cell count is a predictor of negative outcomes in HIV -infected patients and strongly correlates with WHO disease staging. There is lack of data pertaining the relationship between vascular function and nadir CD4 in patients without risk factors of hypertension and diabetes. Therefore we investigated the association between low nadir CD4 T-cells and endothelial function in these otherwise cardiovascular healthy patients. Methods: We conducted a study of 19 HIV-infected men on antiretroviral therapy with undetectable plasma RNA levels without hypertension or diabetes. Vascular reactivity index (VRI), a marker for vascular endothelial function, was measured via VENDYS technique using temperature rebound in response to hyperemic blood flow and vasodilation to the forearm following a 5-minute cuff occlusion of the brachial artery. Results: VRI showed a significant correlation with low nadir CD4 count (p = 0.019) (Figure 1). Lower CD4 counts were associated with significant endothelial dysfunction. We examined the effect of potential mediators on such association. No significant correlation was found with LDL-C (p=0.60), HDL-C (p=0.59), systolic and diastolic blood pressures (p=0.12 and 0.13) or history of smoking (p=0.55) with VRI in the studied HIV cohort. Conclusion: Low nadir CD4 count remained independently associated with vascular reactivity index and thus a significant clinical predictor of endothelial dysfunction in HIV infected patients with no history of hypertension or diabetes even before clinical evidence of cardiovascular disease. Vascular Reactivity Index vs CD4 Nadir(Figure1).