Evaluation Of The Baseline Characteristics And Immunosenescence Of Blood Lymphocytes Among Elderly Hiv Infected Patients In Kisii Teaching And Referral Hospital, Kenya

Abstract

Data on baseline characteristics among HIV infected patients is very important especially among elderly patients seeking critical care. However, this information is widely not considered in Kenya with those seeking treatment at Kisii Teaching and Referral Hospital (KTRH) not exceptional. In addition, it is also not clear if HIV intrinsically accelerating immunosenescence among the elderly HIV-infected persons (EHIP). Despite HIV prevalence being high among elderly globally, the impact of their baseline characteristics on HIV infection and immunosenescence acceleration has not yet been evaluated among elderly HIV infected populations of Kisii. Therefore, this study evaluated the baseline characteristics and alterations in immunosenescence lymphocyte markers frequencies over time among the EHIP aged  50 years against elderly HIV uninfected persons (EHUP) controls. In addition, the relationship between duration of ART and immunosenescence was also determined. A laboratory-based descriptive, cross-sectional study was performed using EHIP attending HIV/AIDS clinic at KTRH. Archived data on baseline characteristics of 1329 EHIP, collected retrospectively between January 2008 and December 2019 was used in this day. A total of 62 HIV infected individuals were sampled from 1329 eligible elderly HIV infected individuals and their blood samples analysed for T, B and NK cell subsets and the expression of immunosenescence markers (CD4+ CCR7+ , CD8+CCR7+ , IgD CD27- and CD56-CD16+ ) frequencies using flow cytometry. In addition, theCD4/CD8 ratio was also determined. Descriptive statistics for summarise for baseline characteristics were done and compared using the Kruskal-Wallis. Wilcoxon signed-rank test was done in collating first and last VL based on demographics. Mean divergences for cell count and proportions of lymphocyte subsets were computed using Student‘s t-test for parametric values. Linear regression analysis was used in assessing the relationship between age in years vs. the proportion of cells. The p-values ≤0.05 were considered statistically important. The results showed that, at the point of recruitment to care, age, WHO AIDS staging, gender and residence have significant impact on the decline of VL and CD4 count in elderly persons living with HIV. Substantial deviations on CD3+ , CD4+ , CD8+ , CD8+CCR7- and CD4+CCR7- cells exists between EHIP and the controls (EHUP) with age, HIV infection and CD4/CD8 ratio being factors attributing to this effect. In addition, there were substantial differences in cell count and percentages of CD19+ , IgD+CD27+ , IgD+CD27- , IgD-CD27- , and IgD-CD27+ lymphocyte subsets between EHIP and controls (EHUP). There were also substantial differences in the frequencies of CD56+CD16+ , CD56- CD16+ , CD56++CD16+ and CD56++CD16- NK cells between EHIP and EHUP. However, there was no significant relationship between the distribution of T, B, and NK leukocyte subsets and the duration on ART. This study shows that HIV infection accelerates immunosenescence in elderly HIV infected people with the baseline characteristics being predictive of care outcome among EHIP seeking care. This study recommends regular monitoring and evaluation of baseline characteristics of EHIP as a guide in patients care. In addition, regular evaluation of; T cell, B cell and NK cell immunosenescence could be a pathway to promotion of health for the elderly living with HIV.