HIV is associated with chronic inflammation and immune activation and increases the risk of venous thromboembolism (VTE) events. Predisposing factors are important in the epidemiology of VTE in the general population but little is known about their presence among people living with HIV (PLWH) in the era of widespread access to antiretroviral therapy.
We included PLWH with VTE in 2005-2017 at 6 sites in the CNICS cohort. We developed a centralized adjudication approach for VTEs with ascertainment based on multiple criteria including diagnoses and procedures, followed by centralized adjudication of primary data by two expert reviewers, and a third reviewer if discrepancies occurred. VTEs were classified by type and anatomic location. Reviewers identified the presence of pre-disposing factors such as bedrest and long plane rides. This analysis included only initial VTEs for those with recurrent events.
We included 318 PLWH with VTE: 181 (57%) deep venous thrombosis (DVT), 139 (44%) pulmonary embolus (PE), and 38 (12%) catheter-associated thrombosis events, including 40 (13%) with multiple types simultaneously (mostly DVT/PE). Two-hundred forty-eight (78%) patients were male; median age was 49 years old (interquartile range [IQR]: 40,55); and 134 (42%) were white, 151 (47%) black, and 26 (8%) Hispanic. Median CD4 count was 312 cells/µL (IQR: 149,548) and 31% had a detectable viral load (≥400 copies/mL). One-hundred forty-four (45%) were current smokers. Most patients had multiple predisposing factors (Table); mean 2.3 (standard deviation [SD] 1.5). Only 33 (10%) had no pre-disposing factor identified. The most common predisposing factors identified included recent hospitalization (134, 42%), infection (133, 42%), or immobilization/bed rest (78, 25%) within the past 90 days, and current IV drug use (65, 20%). Eighty-seven (27%) had both hospitalization and infection in the past 90 days; 54 (17%) had both immobilization/bed rest and hospitalization.
We conducted a robust adjudication process and examined predisposing factors for VTE among PLWH in a large North American cohort. PLWH with VTE were relatively young and most had at least one identified traditional pre-disposing risk factor. In addition, non-traditional risk factors, including IV drug use and recent infection, were common. Almost one-third of patients had detectable viral loads, and almost half were active smokers, suggesting potential modifiable pro-thrombotic risk factors.