University of Georgia

Improving HIV treatment

University of Georgia researcher Amara Ezeamama poses for an outdoor photograph on campus

Low bodily levels of vitamin D may limit the effectiveness of HIV treatment in adults, according to a recent UGA study.

Those carrying the human immunodeficiency virus—commonly known as HIV—often struggle with declining health because their immune systems can’t effectively respond to common pathogens.

But “the magic of antiretroviral therapy lies in its ability to restore immune function,” said study coauthor Amara Ezeamama, assistant professor of epidemiology and biostatistics at the College of Public Health. “With antiretroviral drugs, people with HIV are beginning to live longer lives.”

Still, it has been suspected that certain deficiencies, such as of vitamin D, compromise the functioning of these drugs. Thus “our goal in the study,” said Ezeamama, “was to understand whether vitamin D deficiency limits the amount of immune recovery benefit for persons on HIV treatment.”

She and her colleagues conducted an 18-month trial of 398 HIV-positive adults on “highly active antiretroviral therapy,” or HAART, a “cocktail” of three or more drugs that is currently the most common—and most effective—treatment for these patients. Those on HAART take it daily.

In their study, the researchers measured participants’ immune function at 0, 3, 6, 12, and 18 months, and related it to whether or not they had adequate levels of vitamin D.

A major result was that vitamin D indeed helped the adults’ complement of CD4+T cells recover more quickly from the effects of HIV. CD4+T cells, a type of T cell that helps the immune system fight off pathogens, were critical because of the patients’ weakened immune systems.

In the study, participants with sufficient levels of vitamin D recovered more of their immune function—on average, 65 CD4+T cells more—than those with vitamin D deficiency.

The benefit of vitamin D sufficiency seemed even greater for younger and underweight HIV-positive adults.

“HIV destroys the capacity of the body to mount effective response to pathogens,” Ezeamama said. “Given different vitamin D levels, HIV-positive adults recovered at different rates. We found a relationship between vitamin D and CD4+T cells.

“If we intervene with vitamin D, which is relatively cheap, it could give HIV-infected individuals a modest immune recovery bump that will likely translate into a big public health impact.”

In future studies, she wants to investigate how vitamin D affects immune recovery and long-term health outcomes in HIV-positive children.

“We are now in an era of hope for persons with HIV,” Ezeamama said. “We know that HIV treatment works, and now people can live for several decades with HIV. We can further delay the progress of the disease and maintain survivors on a higher quality of life if we understand the factors that limit the effectiveness of HIV treatment.”