1. PRESENTED AT THE 9TH IAS CONFERENCE ON HIV SCIENCE - PARIS, FRANCE
Outcomes of Routine Viral Load Monitoring in Namibia’s National Antiretroviral Treatment Program
Nicholus Mutenda1; Negussie Taffa2; Drew Baughman2; Manza Agovi3; Michael DeKlerk2; Souleymane Sawadogo2; Clay Roscoe2; Tadesse Teferi1; Harold Kaura4; Adam Wolkon2; Gram Mutandi2; Francina Tjituka1; Dimitri Prybylski2; Ndapewa Hamunime1; Simon Agolory2
Authors affiliation: 1: Directorate of Special Programs (DSP) for HIV, TB and Malaria, Ministry of Health and Social Services (MOHSS), Windhoek, Namibia;, 2: Centers for Disease Control and Prevention (CDC), Windhoek, Namibia;, 3: Global Strategic Information Group, University of California, (UCSF) Namibia, 4: Namibia Institute of Pathology (NIP), Windhoek, Namibia;
Background
Namibia’s antiretroviral treatment (ART) guidelines recommend the use of viral load (VL) testing to monitor HIV treatment as recommended by WHO. VL testing is recommended at 6 months after ART initiation. The guidelines defines VL suppression as HIV RNA <1000 copies/ml, and recommends switch to second-line ART following failure of VL suppression with two consecutive tests performed at 6 and 9 months.
In this study, we describe the level of VL suppression and factors associated with virological failure.
Objective
Assess the level of virological suppression among patients who were on ART for a period of 6-9 months.
Assess the level of VL suppression by age, sex and baseline CD4 count.
Assess the role of timely VL testing for early identification of treatment failure.
Methods
A retrospective cohort analysis of patients initiating ART between January 2014 and March 2015 at public ART facilities in Namibia.
Clinical and laboratory records were matched from two non- interfaced, client-based electronic databases used for patient management and laboratory services.
Matching was performed using probabilistic record linkage (Link Plus v3.0 software) method using patient surname, first name, and date of birth.
VL results were described by age, sex, baseline CD4 cell count.
Factors Associated with VL Failure
Results
Out of 9,063 patients with matched laboratory and clinical records 503 (5.5%) were aged below 15 years and 94.4% were adults aged 15 years and above.
2,536 (27.9%) received a first VL test within 6-9 months of ART initiation.
VL suppression was achieved among 95.5% adults (95% CI: ) and 86.7% children (95% CI: ).
Male patients were 40% more likely to have virological failure compared to females (RR=1.4, 95% CI 1.2, 1.7; P<0.01).
Patients with very low baseline CD4 count (<200cells/µL of blood) had higher rate of virological failure (8.8%) compared to those with higher CD4 count ( cells/µL) (3.6%) [RR=1.8, 1.2, 2.7; P<0.001] and those above 350 cells/µL of blood (2.0%) [RR=4.7, 95% CI 3.3, 6.8; P<0.01].
Patient who received first VL test 9 months after ART initiation had lower suppression rates both for adults (94.0%, 95% CI: ) and children (81.1%, 95% CI: ), P<0.001 compared to those who received it before 9 months.
Variables
Suppressed
Failed
Adjusted OR 95% CI
Gender
Male
2770 (93.8%)
183 (6.2%)
 1.4 (1.2,1.7)***
Female
5842 (95.6%)
269 (4.4%)
1.0
Age Groups
0-14 years (children)
436 (86.7%)
67 (13.3%)
 3.4 (2.5,4.5)***
15-19 years (adolescents)
239 (94.8%)
13 (5.2%)
1.2 (0.7, 2.1)
20-29 years (young adults)
2561 (95.3%)
126 (4.7%)
1.0 (0.8, 1.3)
30 years & above
5375 (95.6%)
246 (4.4%)
Baseline CD4 Count Categories*
<200 cells/µL
1968 (91.2%)
190 (8.8%)
4.7 (3.3,6.8)***
cells/µL
2192 (96.4%)
81 (3.6%)
1.8 (1.2,2.7)**
cells/µL
1714 (98.0%)
35 (2.0%)
Place of ART initiation
Hospital
5057 (94.7%)
283 (5.3%)
 1.2 (0.9,1.6)
Health Centers
1664 (95.4%)
81 (4.6%)
1.1 (0.9, 1.5)
Clinics
1722 (95.6%)
79 (4.4%)
Timing of VL test
After 9 months
3290 (93.2%)
240 (6.8%)
2.4 (1.9, 3.0)***
At 9 months & earlier
4693 (97.1%)
140 (2.9%)
* CD4 >500cells/µL excluded due to small numbers
** P < 0.01
*** P < 0.001
Conclusion and Recommendations:
Among the matched patients in our analysis, there is high level of VL suppression. However, timely measurement of VL suppression levels after ART initiation was found to be very important.
VL suppression was lower among children and patients with low CD4 count; these groups should be prioritized for VL testing in setting where testing maybe limited.
More work is needed to strengthen compliance with the routine VL monitoring guidelines, especially timing, to better detect treatment failure and minimize development of ARV drug resistance.
We were only successful in matching a small number of patients initiating ART (~30%), and the sample may not be representative of new ART patients in Namibia and we have not validated the matched patient records.
Disclaimer: This survey has been supported by PEPFAR through the Centers for Disease Control and Prevention under the terms of Award # HA13. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the Centers for Disease Control and Prevention
PRESENTED AT THE 9TH IAS CONFERENCE ON HIV SCIENCE - PARIS, FRANCE