The Risk of Venous and Arterial Thrombosis in Patients with HIV Infection

Abstract number: P1877

Micieli E, Ageno W, Grossi P, Venco A

Background:  Thromboembolic complications in HIV-infected patients have been reported. To our knowledge, there are no case control studies that compared the prevalence of thromboembolic events between a population of HIV patients and age-matched controls.

Methods:  The charts of 169 HIV-infected patients followed at the local ambulatory for the management of HIV infections were reviewed. All patients were asked to fill a specific questionnaire and were subsequently interviewed. Information on family history of cardiovascular disorders, on the presence of personal risk factors for venous and arterial thrombosis and on previous venous and arterial thrombotic events was collected. All reported events were adjudicated if adequate documentation of objective tests was available. The same information was collected from a population of 180 randomly selected blood donors. These were both active donors and former donors who were excluded because of health problems.

Results:  Mean age was 41.2 years in HIV-infected patients and 40.1 years in controls (P= n.s.). Males were 70.4% in the former and 56.7% in the latter group, respectively (P= 0.0077). A vascular event was documented in 6 HIV-infected patients (3.55%) and in none of controls (P= 0.0108). Vascular events were acute myocardial infarction in 2 patients, deep vein thrombosis in 2 patients, ischemic stroke in 1 patient, and acute arterial thrombosis of a lower limb in 1 patient. Some risk factors were more prevalent in HIV patients than in controls: family history of cardiovascular disorders (36.1% and 23.3%, P= 0.0090), cigarette smoking (60.3% and 24.4%, P < 0.0001), and hypertriglyceridemia (43.8% and 14.4%, P < 0.0001). Other risk factors were more prevalent in controls than in HIV patients: obesity (10% and 1.8%, P= 0.0012) and use of oral contraceptives (29.5% and 2%, P= 0.0001).

Discussion:  HIV infection is associated with an increased risk of thromboembolic complications. Specific risk factors need to be identified.