Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited. Venous and arterial thrombosis in patients with HIV infection Evy Micieli a , Francesco Dentali a , Massimo Giola b , Paolo Grossi a,b , Achille Venco a and Walter Ageno a Thromboembolic complications in HIV-infected patients have been reported. To our knowledge, no case–control studies have compared the prevalence of thromboembolic events between HIV-positive and HIV-negative individuals. One hundred and sixty-nine HIV-infected patients and 180 randomly selected blood donors were enrolled. Selected patients completed a specific questionnaire and were subsequently interviewed. Information was collected on family and personal history of cardiovascular disorders and the presence of personal risk factors for venous and arterial thrombosis. All reported events were adjudicated only if adequate documentation of objective tests was available. Mean age and sex were similar in the two groups. A vascular event was documented in six HIV-infected patients (3.55%) and in none of the controls (P U 0.0108). Family history of cardiovascular disorders, cigarette smoking and hypertriglyceridemia were more prevalent in HIV patients than in controls. In multivariate analysis, neither family traditional cardiovascular risk factors nor HIV infection were independently associated with the presence of thromboembolic events. The results confirm the hypothesis that HIV-positive patients have an increased risk of thromboembolic disorders. Whether this increased risk has been provoked by HIV infection itself or by other associated risk factors for cardiovascular events, such as cigarette smoking and hypertriglyceridemia, remain to be clarified. Blood Coagul Fibrinolysis 18:259–263 ß 2007 Lippincott Williams & Wilkins. Blood Coagulation and Fibrinolysis 2007, 18:259–263 Keywords: arterial thrombosis, human immunodeficiency virus, risk factors, venous thromboembolism a Department of Clinical Medicine, University of Insubria, Varese and b Department of Infectious and Tropical Diseases, University of Insubria and Regional Hospital, Varese, Italy Correspondence and requests for reprints to Francesco Dentali, U.O. Medicina I, Ospedale di Circolo, Viale Borri 57, 21100 Varese, Italy Tel: +39 332 278594; fax: +39 332 278229; e-mail: fdentali@libero.it Received 19 June 2006 Revised 3 January 2007 Accepted 4 January 2007 Introduction AIDS is a disease that leads to death in a short period of time if not adequately treated. In past years, the development of combined antiretroviral therapy and the appropriate use of prophylactic strategies to prevent opportunistic infections have drastically improved the life expectancy of most HIV-infected patients, allowing them to live a long and relatively healthy life. Data from a recent report show that among HIV-infected patients treated at Veterans Affairs Facilities in United States, the all-cause mortality decreased between 1995 and 2001 from 21.3 to 5.0 deaths per 100 patient-years [1]. Since 1998, however, several reports have also suggested that HIV-infected patients are at increased risk of premature cardiovascular thromboembolic events [2 – 4]. On the one hand, accelerated T-cell proliferation, heightened T-cell activation, and high levels of inflammatory markers are commonly associated with HIV infection, and they may increase the risk of arterial and venous events [5]. On the other hand, the widespread use of protease inhibitors may play a central role in atherogenesis and in the subsequent development of arterial thrombosis, inducing deleterious metabolic effects such as insulin resistance and dyslipi- demia [6]. Available data on the actual prevalence of venous and arterial thromboembolic disease in HIV patients, however, are rather inconclusive. Indeed, most of the published studies are actually case reports or noncontrolled, retrospective cohort studies [7–9], and the results of controlled studies are conflicting [10–21]. Our aim was to assess the association of HIV infection with symptomatic thromboembolic events comparing the prevalence of thromboembolic events in a HIV-positive population and in a control, HIV-negative population. Moreover, to further clarify the strength of this associ- ation, the prevalence of risk factors for arterial and venous thromboembolic events has been assessed in the two populations. Materials and methods Patients were recruited from the cohort of outpatients attending the clinic for the management of HIV infections of the Department of Infectious and Tropical Diseases of the Regional Hospital of Varese, Italy. The control group of HIV-negative individuals was recruited among blood donors followed by the Italian Association of Blood Donors, branch of Varese, located in the same hospital. From the registry of the Italian Association of Blood Donors, we randomly selected individuals who attended the clinic of the Italian Association of Blood Original article 259 0957-5235 ß 2007 Lippincott Williams & Wilkins