PURPOSE

CD4 cell-count has been regarded as the key surrogate marker for prognostic staging and therapeutic monitoring of HIV-infected individuals. Our purpose was to assess the probability of maintaining a CD4 count >200 cells/μL in patients with continuous viral suppression and CD4 cell counts >200 cells/μL.

METHODS

Retrospective cohort study of HIV-infected patients, treatment naïve, who started antiretroviral therapy between 2007 and 2011. We estimated the probability of maintaining CD4 counts >200 cells/μL during continuous viral suppression using the Kaplan-Meier method. The hazard ratios of a CD4 count <200 cells/μL were estimated and compared using Cox proportional hazards regression.

RESULTS

401 patients were included: 70.1% men; median age 37 years; 98.8% HIV-1 infected. The median duration of continuous viral suppression with CD4 counts >200 cells/μL was 40.5 months. Ninety-three percent of patients maintained CD4 counts ≥200 cells/μL during the period of continuous viral suppression. Compared with those with an initial CD4 count ≥350 cells/μL, patients with initial CD4 count <300 cells/μL had a significantly higher risk of a CD4 count <200 cells/μL. Patients with viral suppression and CD4 counts ≥350 cells/μL had a 97.1% probability of maintaining CD4 cell counts ≥200 cells/μL for 48 months.

CONCLUSIONS

The probability of a CD4 count <200 cells/μL in an HIV-infected patient with viral suppression and CD4 ≥350 cells/μL was very low. These data suggests less frequent monitoring of CD4 counts in these patients.