Platelet activation and inflammation markers as emerging risk factors for cardiovascular diseases in HIV

Abstract

Background: HIV infection is associated with increased risk of Cardiovascular Diseases (CVD) and risk calculators underpredict these outcomes in infected individuals. The underlying mechanisms leading to high CVD risk are not yet clear. Low-grade inflammation and platelet abnormalities which persist even after individuals undergo successful antiretroviral therapy have been implicated in the development of CVDs in individuals with HIV infection.

Objective: This study evaluated plasma levels of platelet activation and inflammation markers in HIV uninfected, HIV infected subjects receiving Anti-retroviral Therapy (ART) and those naïve to ART.

Materials and Methods: A total of 284 adults comprising of subjects receiving ART (187), ART naïve (32) attending an HIV treatment center and HIV uninfected blood donors (65) were investigated in this analytical cross sectional study. Platelet activation and inflammation markers were assessed by measuring plasma levels of sP-selectin, platelet factor 4 (PF4), IL-6 and tumor necrosis factor alpha (TNF-α).

Results: HIV infected patients had higher levels of sP- selectin, PF4 and IL-6 than uninfected controls (p<0.001). ART naïve subjects had higher levels of PF4 as compared to the individuals receiving ART (p<0.001). Levels of TNF-α did not differ across groups by HIV (p=0.992) or ART status (p=0 993). A positive correlation was observed between IL-6 and sP-selectin levels in HIV infection (r=0.2690; p=0.001) but lacked in the HIV uninfected (r=-0.1065; p=0.5825).

Conclusion: Levels of platelet activation and inflammation markers were elevated in HIV infected individuals regardless of ART and significance of this in HIV- related cardiovascular risk should be investigated further.