Factors associated with a reduced CD4 lymphocyte count response to HAART despite full viral suppression in the...

To describe the prevalence and risk factors of poor CD4 count rise despite a good virological response on highly active antiretroviral treatment (HAART).

The patients from the EuroSIDA study who started HAART with a baseline CD4 count of <350 cells/microL and where all viral load (pVL) measures remained below 500 HIV-1 RNA copies/mL between 6 and 12 months after the start of HAART were included. The risk factors for poor CD4 count rise were analyzed by multiple regression.

Seven hundred and eighty patients were included. A low CD4 count response was observed in 225 patients (29%). The risk factors for this condition were older age, lower CD4 count at baseline, higher increase from the nadir to baseline CD4 count and lower pVL at baseline. Patients taking > or =one drug from each of the three antiviral classes were more likely to have a good CD4 response but a minority of the study participants was taking this treatment regimen (3.1%) and the confidence interval was large.

A poor immune reconstitution despite a good virological control is frequent after initiation of HAART among patients with a baseline CD4 count of <350 cells/microL. The underlying mechanisms leading to this condition seems mainly driven by the age and the baseline immunological and virological status of the patients.