Virologic and Immunologic Response to Highly Active Antiretroviral Therapy

Joint and Separate Analysis for Longitudinal and Survival Data on Mother-to-Child Transmission of HIV Among Infected Mothers on Option B+ at Health Centers in North Shewa Zone, Ethiopia, 2017

Background

Prevention of mother-to-child transmission of HIV (PMTCT) is a frequently used word for programs and intervention methods to decrease the risk of mother-to-child transmission of HIV. The aim of this study was to identify determinants of the reduction of CD4 count through time and the maternal transmission of HIV to their child on the PMTCT program at health centers in North Shewa Zone, Ethiopia.

Methods

The cohort study design was conducted by using secondary data collected from the cohort register of PMTCT starting from September 1, 2014 to November 30, 2017. In this study, a longitudinal study was conducted for two types of result; these were longitudinal response measurements of HIV infected women CD4 count and the time to maternal transmission of HIV taken from 203 patients.

Results

The prevalence rate of HIV infection among exposed infants was 5.58%. Baseline CD4 count, visiting times, weight, and interaction between visiting time and baseline CD4 count had a statistically significant effect on the longitudinal biomarker. From the Weibull AFT model, ART start, partner test, clinical stage, educational status, place of delivery, and MUAC were statistically significant. Hence, as a measurement unit decreased in square root CD4 cell count by 1.18 elevates the risk of maternal transmission of HIV.

Conclusion

In this study, the determinant of mother-to-child transmission of HIV including loss of weight, ART start (ANC), place of delivery at home, illiterate and mother with severe malnutrition, had a significant effect. The longitudinal biomarker also had a strong association with baseline CD4 and the risk of maternal transmission of HIV. Health education should be given about balanced diet, weight control, and take medication for HIV positive patients by the responsible bodies.

Model-based prediction of CD4 cells counts in HIV-infected adults on antiretroviral therapy in Northwest Ethiopia: A flexible mixed effects approach

Background

CD4 cell counts is widely used as a biomarker for treatment progression when studying the efficacy of drugs to treat HIV-infected patients. In the past, it had been also used in determining eligibility to initiate antiretroviral therapy. The main aim of this was to model the evolution of CD4 counts over time and use this model for an early prediction of subject-specific time to cross a pre-specified CD4 threshold.

Methods

Hospital based retrospective cohort study of HIV-infected patients was conducted from January 2009 to December 2014 at University of Gondar hospital, Northwest Ethiopia. Fractional polynomial random effect model is used to model the evolution of CD4 counts over time in response to treatment and to estimate the individual probability to be above a pre-selected CD4 threshold. Human subject research approval for this study was received from University of Gondar Research Ethics Committee and the medical director of the hospital.

Results

A total of 1347 patients were included in the analysis presented in this paper. The cohort contributed a total of 236.58 per 100 person-years of follow-up. Later the data were divided into two periods: the first is the estimation period in which the parameters of the model are estimated and the second is the prediction period. Based on the parameters from the estimation period, model based prediction for the time to cross a threshold was estimated. The correlations between observed and predicted values of CD4 levels in the estimation period were 0.977 and 0.982 for Neverapine and Efavirenz containing regimens, respectively; while the correlation between the observed and predicted CD4 counts in the prediction period are 0.742 and 0.805 for NVP and EFV, respectively.

Conclusions

The model enables us to estimate a subject-specific expected time to cross a CD4 threshold and to estimate a subject-specific probability to have CD4 count above a pre-specified threshold at each time point. By predicting long-term outcomes of CD4 count of the patients one can advise patient about the potential ART benefits that accrue in the long-term.

Human immunodeficiency virus (HIV) latency: the major hurdle in HIV eradication

Failure of highly active antiretroviral therapy to eradicate the human immunodeficiency virus (HIV), even in patients who suppress the virus to undetectable levels for many years, underscores the problems associated with fighting this infection. The existence of persistent infection in certain cellular and anatomical reservoirs appears to be the major hurdle in HIV eradication. The development of therapeutic interventions that eliminate or limit the latent viral pools or prevent the reemergence of the viruses from producing cells will therefore be required to enhance the effectiveness of current antiretroviral strategies. To achieve this goal, there is a pressing need to understand HIV latency at the molecular level to design novel and improved therapies to either eradicate HIV or find a functional cure in which patients could maintain a manageable viral pool without AIDS in the absence of antiretroviral therapy. The integrated proviral genome remains transcriptionally silent for a long period in certain subsets of T cells. This ability to infect cells latently helps HIV to establish a persistent infection despite strong humoral and cellular immune responses against the viral proteins. The main purpose of this report is to provide a general overview of the HIV latency. We will describe the hurdles being faced in eradicating latent HIV proviruses. We will also briefly discuss the ongoing strategies aimed toward curing HIV infection.

Virologic and immunologic response to highly active antiretroviral therapy

Highly active antiretroviral therapy (HAART) delays clinical progression by suppressing viral replication, measured by a substantial reduction in HIV RNA, allowing the immune system to reconstitute, measured in most studies by an increase in CD4 cells. These virologic and immunologic consequences do not occur uniformly among HAART users. Markers of HIV disease stage at the time of HAART initiation are critical determinants of the progression while receiving HAART. In this report, we review studies describing the heterogeneous virologic and immunologic progression after the initiation of HAART, discuss methodologic concerns in the study of the response of biomarkers, and update findings obtained in the Multicenter AIDS Cohort Study, which show that CD4 cell count, history of antiretroviral therapy, and age at the time of initiation are independent determinants of response.

Update on the Virologic and Immunologic Response to Highly Active Antiretroviral Therapy

Highly active antiretroviral therapy (HAART) delays clinical progression by suppressing viral replication, measured by a substantial reduction in HIV RNA, allowing the immune system to reconstitute, measured in most studies by an increase in CD4 cells. These virologic and immunologic consequences do not occur uniformly among HAART users. Markers of HIV disease stage at the time of HAART initiation are critical determinants of the progression while receiving HAART. In this report, we review studies describing the heterogeneous virologic and immunologic progression after the initiation of HAART, discuss methodologic concerns in the study of the response of biomarkers, and update findings obtained in the Multicenter AIDS Cohort Study, which show that CD4 cell count, history of antiretroviral therapy, and age at the time of initiation are independent determinants of response.

Improvement of Systemic Human Immunodeficiency Virus--Related Non-Hodgkin Lymphoma Outcome in the Era of Highly Active Antiretroviral Therapy

To assess the impact of highly active antiretroviral therapy (HAART) on the outcome of systemic human immunodeficiency virus-related non-Hodgkin lymphoma (HIV-NHL), we retrospectively analyzed 235 patients in whom HIV-NHL was diagnosed from April 1988 through December 1999. A multivariate Cox proportional hazards model was used to estimate prognostic factors for overall survival (OS), progression-free survival (PFS), and disease-free survival (DFS). Complete remission occurred in 49% of patients, and the 3-year rates of OS, PFS, and DFS were 19%, 49%, and 73%, respectively. The greatest risk for shortened OS, PFS, and DFS was associated with no HAART use (compared with long-term HAART use); hazard ratios were 17.42 (95% confidence interval [CI], 17.42-40.25), 9.11 (95% CI, 3.71-22.32), and 8.54 (95% CI, 1.19-61.11), respectively. Our study suggests that the long-term use of HAART may favorably change the outcome for patients with systemic HIV-NHL.