Researchers found that HIV-infected infants treated with one or two antiretroviral drugs within two months of birth were less likely to develop AIDS by their third birthday than were infants who were 3 or 4 months old when treatment was initiated. Infants who received a combination of three antiretroviral drugs did even better.
"This is an important finding because there's been a lot of controversy in the literature as to whether infected but asymptomatic infants should be started on therapy right away," said the study's senior author Yvonne Maldonado, MD, a pediatric infectious disease expert at Lucile Packard Children's Hospital and an associate professor of pediatrics at Stanford's School of Medicine.
Without any kind of treatment, about 20 to 30 percent of HIV-infected infants will develop AIDS by around 4 months of age. The rest will not have advanced symptoms until they are about 6 years old. The study, published May 11 in the Journal of the American Medical Association, suggests that early treatment might be appropriate for at least some apparently healthy infected infants.
"There is a significant difference in the likelihood of disease progression [with earlier treatment], even though there is only about a month separating the initiation of therapy in the two groups," Maldonado said. "And none of the children who received triple therapy progressed to AIDS before their third birthday, regardless of the age at which they began therapy." (Therapy with a combination of three drugs, known as highly active antiretroviral therapy, or HAART, was not available when the study began in 1988.)
Current guidelines for treating HIV-infected infants leave the decision of when to begin treatment to the child's physician-in part because the long-term effects of ongoing antiretroviral treatment are not known. Concerns about the drugs' possible toxic side-effects and the development of viral resistance to available treatments must be balanced against a desire to do everything possible to keep infected children healthy.
Maldonado and her colleagues collected data from hospitals throughout northern California over a 17- year period. Statistical calculations indicate that their sample of 205 children represents nearly every HIV-infected child born in the area during that time-an unbiased sample that allowed them to analyze all infected babies, not just the sickest. "We were able to analyze children with the full spectrum of disease across many years, rather than using mathematical models to predict the development of illness in the children," said Maldonado. "We were able to see the real distribution of illness, what kinds of treatment the children were given and the ages when they started treatment."