August 5, 2014
A study published in the journal AIDS "suggest[s] potential mechanisms that might lead to increased risk for cardiovascular disease in HIV," according to its authors. HIV-infected men were found to have more epicardial adipose tissue, which in turn was associated with coronary artery plaques, than HIV-uninfected men.
The U.S. trial administered noncontrast computed tomography (CT) to 932 men between 40 and 70 years of age. Of these, 579 were HIV-infected and 353 were not infected. CT measured epicardial adipose tissue volume and coronary artery calcium in all participants.
The HIV-infected participants had substantially more epicardial adipose tissue than those not infected (P = .001), a difference that was even more pronounced for those who had been on antiretroviral therapy for a long time (P = .02), especially if they had taken zidovudine (AZT, Retrovir) (P < .05).
The study also showed that epicardial adipose tissue was linked to having coronary artery plaque (P = .006), and specifically to having noncalcified plaque (P = .001). Noncalcified plaque is the most likely type of coronary artery plaque to burst, and therefore the most dangerous. In those with coronary artery calcium, its volume was associated with having epicardial adipose tissue (P = .006), but not with HIV status as such.
The researchers concluded that the greater volume of epicardial fat in HIV-infected men and its link to coronary plaque, as well as to long-term antiretroviral therapy, may be one of the reasons for the higher cardiovascular disease risk in HIV-infected people.
Barbara Jungwirth is a freelance writer and translator based in New York.
Follow Barbara on Twitter: @reliabletran.