The investigators calculated incidence rates of new AIDS-related events occurring during HIV treatment in patients with pretreatment CD4+ cell counts of <200 cells/mm3 during period 1 (pre-HAART era, 1990-1995; 88 patients) and period 2 (HAART era, 1996-2004; 214 patients) according to CD4+ cell count responses while receiving treatment.

They then compared the rates of AIDS-related events from period 2 with those from period 1 according to specific CD4+ cell count response categories and rates of AIDS-related events for various viral load ranges within CD4+ cell count categories during period 2.

Results

·         For period 2 patients with CD4+ cell counts <50 cells/mm3 and viral loads >100,000 copies/mL, the rate of AIDS-related events was significantly lower than that for period 1 patients with CD4+ cell counts <50 cells/mm3. This held true for patients with CD4+ cell counts <100 cells/mm3.

·         There were also significantly fewer AIDS-related events in period 2  than in period 1, including those events occurring among period 2 patients with viral loads >100,000 copies/mL.

·         Similarly, for patients with CD4+ cell counts of 100-200 cells/mm3, there were fewer AIDS-related events in period  than in period 1, even for patients in period 2 with viral loads >100,000 copies/mL (15.4 events per 100 person-years; P=.04).

The study authors conclude, “Our data suggest that, even among patients with late-stage HIV infection and inadequate CD4+ cell count and viral load responses to HIV therapy, maintaining HAART may reduce the incidence of AIDS-related events.

Department of Internal Medicine, University of Michigan Health System, Ann Arbor, MI, USA.

02/25/06

Reference
T Gandhi and others. Effect of maintaining highly active antiretroviral therapy on AIDS events among patients with late-stage HIV infection and inadequate response to therapy. Clinical Infectious DIseases 42(6): 878-884. March 15, 2006.