Being infected with HIV biologically ages a person an average of five years, at least according to one measure: the epigenetic markers on his or her DNA.
Why it matters:
Antiretroviral therapy is allowing people infected with HIV to live longer, but doctors have noted that these patients may be aging faster. HIV-positive individuals appear to be at earlier risk for age-related diseases, such as heart disease, cancer, and dementia. Previous studies have estimated up to 20 years of biological age advancement associated with HIV infection, but the molecular mechanisms connecting HIV to accelerated aging remain unclear.
The nitty gritty:
Researchers took DNA from 181 white males. Of these men, 44 were HIV-negative and the others were HIV-positive, but otherwise healthy. They inspected a kind of epigenetic change in the DNA, called methylation, which can be used as a biological clock. They discovered that HIV-positive participants had methylation patterns suggestive of a biological age an average of five years older than they actually were. This advanced biological aging was also associated with a 19 percent increased risk of mortality. The study was published Thursday in Molecular Cell.
But keep in mind:
The HIV-positive participants included in the analysis all had infections that were well-treated with combination antiretroviral therapy (cART). Living longer with HIV and antiretroviral treatment go hand-in-hand, so the study can’t separate the impact of HIV and treatment itself.
You’ll want to know:
Lead investigator Dr. Howard S. Fox was surprised to find that age advancement was independent of the duration of the infection. Whether someone was infected recently, or has been managing the HIV infection for a long time, the methylation patterns remained the same.
What they’re saying:
This area of research has sparked some controversy. Some studies have suggested that people with HIV were living normal life spans, said Dr. Warner Greene, director of the Gladstone Institute for Virology and Immunology at the University of California, San Francisco. But as this population continues to age, he said, “I suspect that that will not stand the test of time.”
Another well-conducted analysis of HIV and methylation patters concluded that infection was associated with 13 to 15 years of age advancement. “I wouldn’t become too fixated on five years versus 15 years,” Greene said. “It’s somewhat reassuring that most studies are pointed in the same direction.”
The bottom line:
While antiretrovirals are great at prolonging life, HIV infection increases the risk of age-related diseases. Doctors should consider screening for these conditions earlier, and HIV-positive patients should aim to mitigate this risk by abstaining from drugs and alcohol, eating healthy, and exercising.