Waiting to begin antiretroviral (ARV) treatment for HIV until 12 months after the estimated date of seroconversion (EDS) decreases the likelihood of immune reconstitution. Publishing their findings in JAMA Internal Medicine, researchers conducted an observational study of 1,119 people living with HIV who had documented EDS and who achieved a fully suppressed viral load through ARV treatment.

The researchers compared the participants to a population of HIV-negative people, who had a median CD4 count of approximately 900.

Among the HIV-positive group, those who started ARVs within a year of EDS reached a normal CD4 level in 38.4 percent of cases, compared with 28.3 percent of those who started ARVs a year or more after EDS.

The investigators found that three stratified levels of CD4 recovery—whether the count rose no higher than 500, settled between 500 and 899, or reached at least 900—correlated to similarly stratified decreases in the risk of AIDS, as well as stratified greater likelihoods of reversion of markers of immune activation, dysfunction, and responsiveness to normal levels (that is, to levels of the markers that are found in HIV-negative people).

The participants who began the study with more than 500 CD4s were twice as likely to reach normal CD4 levels, and four times as likely to do so if they started ARVs with CD4s above 500. Notably, those who began the study and ARVs with CD4s above 500 were 80 percent less likely to reach normal CD4 levels if they started treatment 12 months or more after EDS.

Those who started ARVs within 12 months of EDS had a 7.8 percent risk of AIDS, compared with 15.3 percent among those who started treatment after 12 months. The respective risks for reduced T-cell activation and responsiveness to the hepatitis B virus (HBV) vaccine were 12 vs. 15.6 percent and 67.9 vs. 50.9 percent.

To read the study abstract, click here.