CD4 CELL CHANGE RATES IN HIV-INFECTED PATIENTS AFTER HIGHLY ACTIVE ANTIRETROVI- RAL THERAPY: RETROSPECTIVE COHORT STUDY 1999-2014

SARA JAMBARSANG¹, ALIREZA AKBARZADEH BAGHBAN^*2, FARID ZAYERI³, SEYED SAEED HASHEMI NAZARI⁴, ALI NIKFARJAM⁵, ALI MORADI

¹Department of Biostatistics, PhD candidate, Faculty of Paramedical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran -²PhD, Associate Professor, Proteomics Research Center, Department of Basic Sciences, School of Rehabilitation, Shahid Beheshti University of Medical Sciences, Tehran, Iran - ³PhD, Associate professor, Proteomics Research Center and Department of Biostatistics, Faculty of Paramedical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran - ⁴MD, MPH, PhD, Assistant professor of Epidemiology, Department of Epidemiology, School of Public Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran - ⁵MD-MPH, Deputy of health, Tehran University of medical sciences, Tehran, Iran - ⁶Asadabad Health and Treatment Network, Hamadan University of Medical Sciences, Hamadan, Iran

Background and purpose: Determination if treatment of HIV-infected patients subject to highly active antiretroviral therapy resulted in decreased viral replication and increased CD4 cell counts. The CD4 cell count at initiation was the dominant prognostic factor in patients starting HAART. The objective was to identify the effect of HAART on the transition rate between CD4 cell states based on a multi-state Markov model.

Methodology: This was an observational cohort study of 305 HIV-positive patients between 1999 and 2014 who were divided into two groups. One group of 179 patients had not received antiretroviral therapy and one group of 126 patients had received HAART. Both had been referred to the Iranian Research Center for HIV/AIDS.

Results: HIV-positive patients on HAART showed half the hazard of progression to death than those in the non-HAART group. The rate of recovery from state 2 of CD4 cells to state 1 in the HAART group was significantly greater than in the non-HAART group at HR = 2.5 (95% CI: 1.38, 4.70). The probability of recovery after 36 months from each state was estimated using Markov model.

Conclusion: It was found that the effect of HAART on the rate of recovery was significant only for patients that begin therapy from a CD4 value of >200 cells/ml. As treatment continued from three to five years, the probability of reconstitution of CD4 cells from <200 cells/ml to a normal nadir increased from 0.53 to 0.61. Our findings have important implications for clinical management and should be taken into account in future treatment guidelines.