Factors Associated with Immune Discordant Responses in Treated HIV-infected Omani Patients

Abstract

Background: Despite sustained viral control by antiretroviral therapy (ART), some HIV-infected patients do not recover normal CD4+ T cell counts. This Discordant Immune Response (DIR) increases the risk of opportunistic infections. Objective: To evaluate the factors associated with DIR in HIV-infected Omani patients attending public sector clinics. Methods: All HIV-infected patients receiving ART with regular follow-up visits were eligible for this study. The DIR group comprised patients on ART for at least two years with plasma HIV viral load < 50 copies/mL and helper CD4+ T cell counts below 350 cells/μl. The Concordant Immune Responses (CIR) group was similar to DIR but with CD4+ T cell counts above 350 cells/μl. Univariate and multivariate analyses using logistic regression models were used to assess the impact of demographic characteristics, clinical, immunological and virological parameters, type of ART regimens, tuberculosis and other opportunistic co-infections on DIR. Results: Among 153 enrolled participants, 28 and 76 patients were identified as having DIR and CIR, respectively. The multivariate analysis revealed that the only factors independently associated with DIR after adjustment were age (odds ratio [OR] 1.13; 95% confidence interval [CI] 1.04-1.23), baseline CD4+ T cell count (OR: 0.98; CI: 0.97-0.99) and baseline CD56+ cell count (OR: 0.97; CI: 0.96-0.99). Conclusion: Collectively, these findings suggest that a significant proportion of HIV-infected Omani patients develop DIR totaling 27%, and efforts should be made to improve early identification of these patients who tend to experience poor clinical outcomes.