New research suggests that certain antiretroviral treatment (ART) may increase a person’s risk for heart disease, yet scientists believe that its benefits still far outweighs the harm caused by any of its side effects.
If these results, obtained from early animal testing, are also found in later studies involving humans, it may result in future treatment of HIV/AIDS including prevention or treatment of heart disease as well.
"There is, as yet, no hard data linking any form of heart disease to HIV or its treatments,” said Dr Francois Venter, Deputy Executive Director Wits Reproductive Health and HIV Institute (WRHI). “There's lots of stuff that is worrying, and lots of research looking at it, but at the moment, HIV-positive people should be looked after in the same way as HIV-negative people, in terms of their cardiovascular health.”
Despite its life-saving capabilities, ART (like most medications), has negative side effects such as diarrhoea, pain and in some cases lipid derangements which causes fat to accumulate on irregular parts of the body. According to 2009 statistics, 5.6-million South Africans are infected with HIV and just under two million are using ART.
The study looked at the effects of the protease inhibitor Lopinavir/Ritonavir (branded as Aluvia) - an antiretroviral (ARV) used in second-line treatment for HIV/AIDS – on heart function. It is estimated that around five percent of HIV patients on ARVs in South Africa use Aluvia in their treatment regimen.
Early data shows that the use of this therapy was associated with increased body weight and bad cholesterol levels which are risk factors for heart disease, the lead researcher Professor Faadiel Essop of the cardio-metabolic research group from the Department of Physiological Sciences said in a Stellenbosch University statement.
“Although ART enhances the life expectancy and quality of life of HIV-infected individuals, there is an increased emphasis on ART-mediated metabolic derangements [such as irregular fat accumulation] and its potential risk for heart diseases in the long-term,” Essop explained. “Interestingly, such changes resemble the metabolic syndrome, a combination of risk factors that predispose to the future onset of type 2 diabetes and cardiovascular diseases.”
Since the ART roll-out has markedly improved over the last decade these metabolic perturbations will increasingly manifest in people following the treatment. “ARTs may further fuel the growing burden of cardio-metabolic diseases, it seems,” said Essop.
The researchers suspect that side effects linked with heart disease will only take effect after about a year’s treatment, and even then the benefits of the drug outweigh the risk.
“We need to find out what mechanisms are behind the side-effects and how the drug might be increasing a patient’s risk of contracting specific heart diseases,” said Kathleen Reyskens, a PhD student who was part of the research team. “In this way, clinicians will be able to benefit from our basic science research.”
A fellow researcher, Kim Strauss, who presented the results of the study at a conference of the Physiological Society of Southern Africa at Stellenbosch University earlier this week, said that Aluvia also affected heart functioning through its increased production of reactive oxygen species (ROS) - low levels of ROS occur naturally in the body, however increased levels lead to oxidative stress and cell death – which lowers the functioning of the heart, and possibly also other organs, said Strauss.
For the moment, Venter suggests that, HIV-positive people should look after their cardiovascular health in the same way as HIV-negative people. “It's easy - don't smoke, keep your weight under control, drink alcohol moderately, and check your blood pressure, sugar and cholesterol every few years or so," Venter said.