CASCADE analysis finds antiretroviral treatment benefits are evident below CD4 count of 500, uncertain above this level

aidsmap.com: "Starting antiretroviral therapy with a CD4 cell count between 350 and 500 cells/mm3 reduces the likelihood of HIV disease progression and death relative to initiation below 350 cells/mm3, according to findings from the large CASCADE study presented on Thursday at the Eighteenth International AIDS Conference in Vienna. Starting treatment with more than 500 cells/mm3 did not appear to confer additional benefit, but this analysis did not take into account non-AIDS-related conditions.

"Numerous randomised trials have demonstrated the benefits of starting antiretroviral treatment before significant immune system damage occurs; that is, before the CD4 cell count falls much below 350 cells/mm3 and certainly before it hits 200 cells/mm3."