Research calls for start of HIV treatment within 12 months of infection

15 January 2015
An HIV ribbon

Emerging research suggests that starting antiretroviral treatment (ART) at a CD4 count of 500 cells/mm3– the current treatment initiation threshold – is inadequate for normalising the functioning of the immune system. Contributing to this knowledge, a study published in JAMA states that starting ART within 12 months of becoming HIV positive, regardless of whether CD4 count has dropped to 500 cells/mm3 or not, results in measureable and significant immunological benefits.

The current treatment threshold of 500 cells/mm3 is based on the normal average CD4 count for HIV negative adults. However, the researchers found that the average number of CD4 cells is actually much higher than expected. They pulled data from 16,000 HIV negative adults, and concluded that the normal range for CD4 count cells to be between 700, and 1,100 cells/mm3, or an average of 900 CD4 cells/mm3. To better understand what this means for people newly infected with HIV in relation to early or delayed initiation of ART, health-related information of 1,119 HIV positive participants were analysed.

This analysis revealed that nearly 40 percent of the participants achieved a CD4 count of about 900 cells/mm3 when ART was initiated within 12 months of becoming infected. Of the participants who started ART more than 12 months after becoming infected, only 30 percent were able to reach a CD4 count within the normal range. Future testing revealed that the closer the participant’s CD4 count was to 900 cells/mm3, the more likely their immune system was to respond as a person who was not living with HIV. This included having a better response to vaccination against Hepatitis B.

The study concluded that starting ART shortly after HIV infection is highly beneficial. Waiting for the CD4 count to drop below the 500 cells/mm3 threshold allows HIV more time to irreversible damage the immune system, making it less effective. Also, starting ART when the immune system is not greatly weakened ensures that treatment is generally well tolerated. The research underlines the importance of a public health strategy that includes frequent HIV testing for people at risk, and early initiation of ART after diagnosis.