New findings suggest that HIV-infected patients may delay the onset of AIDS by starting drug therapy earlier while their immune systems are stronger. Researchers including Lauren Cain, a research fellow at HSPH, recommend that patients start treatment earlier than current U.S. guidelines in order to fully benefit.

The optimal time to initiate combined antiretroviral therapy (cART) is still being debated in the medical community. In the United States, the Department of Health and Human Services issued revised guidelines in 2009 recommending that patients start treatment when their CD4 cell count dropped below 500 cells/mm3, rather than the previous threshold of 350 cells/mm3, but disagreements remain. In Europe, most guidelines still suggest initiation when CD4 cell count first drops below 350 cells/mm3.

The benefits of early treatment include preserving immune function, reducing chronic inflammation, preventing HIV transmission, and prolonging survival, Cain said. However, early initiation may also result in adverse side effects and the development of drug resistance.

Cain and her colleagues found that initiating drug therapy when the CD4 cell count first drops below 500 cells/mm3 is beneficial in delaying the onset of AIDS. However, these patients were as likely to die within five years as those initiating cART when their CD4 cell count was at 350 cells/mm3.

“Our findings stress the need for early initiation when CD4 cell counts are still above 500 cells/mm3,” Cain said.

The study appeared in the April 19 edition of the Annals of Internal Medicine. Read abstract