A recent study has found that most HIV-positive adolescents originally infected at or near birth in the United States have undetectable viral loads and fairly good immune health. The paper, published online March 9 in the Journal of Acquired Immune Deficiency Syndromes, also reports that children born around the time that combination therapy became the norm in the late 1990s are doing better than kids born when therapy was limited to one or two of the older antiretroviral (ARV) drugs.

The use of ARV therapy to prevent HIV transmission from mother to child has all but eliminated the risk of a child being born with HIV in the United States today. There remain, however, a sizeable number of HIV-positive children who were born before ARV prophylaxis in pregnant women became the norm.

Current pediatric guidelines for ARV treatment of HIV-positive children recommend that most kids start therapy at a young age and well before the virus significantly damages the immune system. Unfortunately for HIV-positive kids born before the mid 1990s, HIV drug therapy back then was not considered highly effective. And while children—especially babies—still have few drug options to choose from, combination therapy is widely available today.

To determine how HIV-positive children who've grown into adolescence are faring these days, and to determine the factors with the greatest impact on immune health and viral suppression, Russell Van Dyke, MD, from Tulane University in New Orleans, and his colleagues examined data on 451 HIV-positive kids enrolled in the Adolescent Master Protocol (AMP)—a cohort of children between 7 and 16 years old—of the pediatric AIDS Clinical Trials Group (ACTG) through 2009.

Van Dyke's team analyzed each participant's virus levels and CD4 percentage upon entering the adolescent cohort. CD4 percentages are used because absolute numbers vary widely in children, while percentages are more consistent. The team also looked at each participant's previous health, ARV use and year of birth. In order to analyze the effect of ARV treatment, Van Dyke and his colleagues split the participants into four cohorts: those born between 1991 and 1993, those born in 1994 or 1995, and those born either in 1996 or 1997, or between 1998 and 2002.

Overall, the children were doing quite well as they entered adolescent care. Of the 451 kids—half were female and 94 percent were black or Latino—68 percent had undetectable viral loads upon entering the AMP, and 78 percent had a CD4 percentage of 25 or higher (considered normal). The average age of the kids at study entry was 12 years, most had been on ARVs for at least 11 years, and most had taken at least five different regimens. About one quarter had a history of an AIDS-defining condition.

Van Dyke and his colleagues next looked for factors that influenced whether a child would have either a CD4 percentage of 25 or higher, or a viral load of less than 400 copies upon entering adolescent care. As for CD4 percentage, the team found that participants who had fully suppressed HIV before entering the adolescent program were most likely to have a healthy CD4 percentage, as were those who started HIV treatment at a higher CD4 count and those who started ARVs at a younger age. In regards to virus levels at AMP entry, male participants, those on ARV treatment, and those who were born in more recent years were most likely to have an undetectable HIV level at the time they entered adolescent care.

Though these data are encouraging, the authors caution that other studies are beginning to document long-term health consequences of both HIV infection and ARV therapy in kids who were birth with the virus. These include problems such as cardiovascular disease and diabetes, as well as bone problems and body shape changes. These challenges are compounded by the fact that most children had fewer and poorer ARV options than adults in earlier years, and that most struggled with adherence.

Despite this, the authors conclude: “Advances in [ARV therapy] for children over the past two decades have substantially improved the outcome for children with perinatally acquired HIV infection surviving to adolescence and young adulthood.”