Injection Drug Use as a 'Second Hit' in the Pathogenesis of HlV-associated Pulmonary Hypertension

摘要

HIV-associated pulmonary arterial hypertension (HIV-PAH) is a serious complication that develops in approximately 1:200 of HIV-infected individuals, and an even higher prevalence of echocardiographic signs of pulmonary hypertension indicates that the disease may be more common than previously thought (1-3). Mortality is high, even in the era of antiretroviral therapy (ART) (4). Lower CD4 cell count has been associated with HIV-PAH, but successful treatment with ART has not reduced prevalence, suggesting that factors other than HIV may contribute to disease (4). Although HIV viral proteins have been suggested to play a role in the pathogenesis of HIV-PAH, not all patients with HIV develop the disease, leading to the investigation of other risk factors, or "second-hit" events (Figure 1). Intravenous drug use in HIV infection is one potential "second hit" that has been associated with HIV-PAH (5); however, the contribution of specific illicit drugs such as opioids or amphetamine derivatives, and the mechanism by which these drugs contribute to pulmonary vasculopathy in HIV-PAH, is not known.