Treatment guidelines should place more emphasis on CD4+ counts than on viral loads
Graham McKerrow, HIV i-Base
Official guidelines on when to start HAART in asymptomatic people with HIV should place more emphasis on CD4+ T cell counts than on viral loads, according to research published in the journal AIDS.
The message from Dr Timothy Sterling and colleagues at Johns Hopkins University, Baltimore, is particularly pertinent to guidelines published by the International AIDS Society (IAS) and the US Department of Health and Human Services (DHHS). Current British guidelines, last updated by the British HIV Association (BHIVA) in July 2001, already place more emphasis on CD4+ counts.
The American guidelines say HAART should be started in patients with CD4+ T cell counts <350 cells/mm3. If the count is >350 the IAS guidelines say treatment should be started if the HIV-1 RNA level exceeds 5,000 copies/mL. The US DHHS guidelines set that figure at 55,000 copies/mL. The British advice is that treatment should be started if someone’s CD4+ count falls below 200. BHIVA says that if the count is between 200 and 350 treatment should be started if the count is falling fast, there are other symptoms, there is a high viral load or the patient wishes to start treatment.
Researchers assessed the outcomes of 530 patients starting HAART compared with 484 who did not receive HAART, at the Johns Hopkins Hospital HIV Clinic.
They found that HAART resulted in decreased disease progression among people with fewer than 200 cells per microlitre prior to treatment. Among people receiving HAART, viral load prior to therapy was not associated with HIV disease progression within CD4 T-lymphocyte count strata. Analysis that adjusted for age, sex, race, prior opportunistic infection, and CD4 T lymphocytes, found that a CD4 count of 200 or less was the strongest predictor of disease progression.
Viral load prior to HAART of less than 5,000 copies/mL or of between 5001 and 55,000 copies/mL or greater than 55,000 copies/mL was not associated with disease progression on therapy. There was no difference between the sexes on disease progression on treatment.
The researchers report: “This study demonstrated that over an average of 22 months of follow-up, CD4 T lymphocyte counts were better than HIV-1 RNA levels in predicting which patients would derive clinical benefit from HAART.” And they write: “In persons who received HAART, we did not detect an association between HIV-1 RNA level prior to initiating HAART and subsequent disease progression.”
They conclude: “Our data suggest that current guidelines for initiating HAART should place greater emphasis on CD4 lymphocyte than HIV-1 RNA level for both men and women.” They go on to say that further longitudinal follow-up will be needed to better ascertain whether HAART initiated at >200 CD4+ T cells per microlitre is effective in slowing disease progression.
Sterling TR, Chaisson RE, and Moore RD. HIV-1 RNA, CD4 T-lymphocytes, and clinical response to highly active antiretroviral therapy. AIDS 2001 Nov 23;15(17):2251-7.