Various studies have been conducted to evaluate the role of antiretroviral therapy in the onset of cardiovascular risk among HIV-1-infected patients, while fewer data are available regarding antiretroviral-naïve patients. Our objective was to evaluate the cardiovascular risk among naïve subjects examining traditional risk factors, immunovirologic parameters, assessing the Framingham risk score (FRS), and detecting the presence of subclinical carotid lesions by means of color Doppler ultrasonography. One hundred seventy-two antiretroviral-naïve patients underwent color Doppler ultrasonography. An intima-media thickness (IMT) greater than 0.9 mm and/or atherosclerotic plaques were considered pathologic findings. Demographic, immunovirologic data, and risk factors for cardiovascular disease were collected. The 10-year probability of acute coronary events was assessed by the FRS. The statistical analysis was performed using t test and chi(2), Fisher's test, and conditional multiple logistic. Thirty-six patients (20.9%) had lesions at ultrasonographic investigation. The presence of lesions was significantly related to male gender (p = 0.005), age (p = 0.003), sedentary life (p = 0.05), Centers for Disease Control and Prevention (CDC) group C or CD4(+) less than 150 cells/mm(3), and viral load (VL) > 100,000 copies per milliliter (p = 0.04). The presence of subclinical carotid lesions showed a highly significant direct association with the estimated FRS (p < 0.002). The presence of subclinical atheromasic lesion results was also high among antiretroviral-naïve patients. FRS is highly predictive of the lesions, but also an advanced stage of disease plays a significant role. Our data support the hypothesis that HIV infection per se is a risk factor for atherosclerosis. We recommend an ultrasonographic assessment both among patients with FRS 6% or more and among those in advanced stage of disease.