Page 345 - SAHCS HIVMed Journal Vol 20 No 1 2019

Page 2 of 8 Original Research

single adherence measurement tool that has the attributes characteristics of children and their primary caregivers. The
of being simple to use, non-invasive, sufficiently sensitive, questionnaire also explored challenges faced by caregivers
specific and predictive of adherence. Access to viral load regarding taking care of the orphans that could potentially
monitoring in much of Africa is limited by its cost and general lead to poor adherence. A modified indicator-based approach
unavailability. Therefore, an alternative multi-method tool (as described in the World Health Organization manual) was
26
may be useful in resource-limited countries. The CD4 cell used to measure adherence among HIV-infected orphans.
count has been used as an indirect measure of cART adherence Using this approach, the two core adherence indicators used
but on its own is nonspecific and too insensitive to provide to measure adherence in orphans were caregiver self-report
accurate adherence information. 12,13 The measurement of and clinic appointment records. Caregiver self-report
blood drug levels, that is, pharmacokinetic or therapeutic drug involved questioning the primary caregiver on the number of
monitoring, provides a very specific and generally sensitive doses of antiretroviral therapy that had been omitted in the
measure of adherence but is limited due to lack of access past 3 days in a non-judgmental manner. Missing one or
in many low and middle-income countries (LMICs). Trough more doses in 3 days was defined as an equivalent of less
plasma concentration of nevirapine (NVP) of > 3.0 mg/L than 95% adherence. Retrospective record review of patients’
has been suggested as an indicator of adherence. 14,15 Mghamba files was performed to retrieve data on the pattern of clinic
et al. recommended the use of NVP plasma concentration in attendance of the orphans. Adequate adherence to cART was
the assessment of adherence in HIV-infected children as the defined when patients attended the CTC on or before the day
concentration is a good predictor of adherence. 16 of their scheduled appointment or within 3 days of their
appointment. 26
Factors such as characteristics of a child, caregiver
(surviving parent or extended family), cART regimen, social The ages of orphans were grouped into three (2–4, 5–9 and
challenges and disclosure of HIV status to the child affect 10–14 years) for descriptive purposes and grouped into two
cART adherence among orphans. 17,18,19,20,21,22,23 Reliable and (2–9 and 10–14 years) for the analysis of association. The
consistent ways of measuring adherence to therapy would pattern of CD4 counts over time was also collected using the
help early detection of patients with poor adherence and retrospective record review. Immune status was categorised
allow for immediate and appropriate interventions. 24,25 as good immune status if the percentage of CD4 > 25% for
children below 5 years or CD4 count > 500 for children above
Study objective 5 years. This pattern of changes in CD4 counts was studied
27
to determine response to cART, as well as using it as a
This study aims to report the extent of adherence to cART measure of adherence.
among HIV-infected orphans by assessing caregivers’ self-
report, consistency of clinic attendance, CD4 cell counts and A blood sample of 2 millilitres (2 mL) was collected from each
NVP plasma levels among HIV-infected orphans and child in an ethylene diamine tetra-acetic acid tube. The blood
determining factors that may hinder adherence in this samples were centrifuged immediately to obtain plasma, and
population. these samples were later stored at −80 °C until drug assay.
Nevirapine plasma concentration was determined by high-
Methods performance liquid chromatography (HPLC) based on the
28
Study design, setting and participants method described by Kappelhoff et al. This was carried out
in the Muhimbili University of Health and Allied Sciences
This is a cross-sectional study conducted between June and (MUHAS) – Swedish International Development Cooperation
September 2015 at three urban district specialised paediatric Agency (Sida) Bioanalytical Laboratory, Unit of Pharmacology
HIV care and treatment centres (CTCs) within the city of Dar and Therapeutics, School of Pharmacy, MUHAS in Dar es
es Salaam, Tanzania. These sites had a high paediatric patient Salaam, Tanzania. Nevirapine concentrations in patient test
enrolment with similar patient population demographics. samples were calculated by a linear regression equation
The study participants were enrolled consecutively as long as (model) from calibration curve. Nevirapine plasma
they met the inclusion criteria until the required sample was concentration ≥ 3 µg/mL was categorised as good adherence.
achieved. A study sample of 216 participants was required This cut-off point was based on the steady-state trough
based on the estimated paediatric cART adherence in concentration reached in the pharmacokinetic curve for NVP
Tanzania by Mghamba et al. The study included HIV- at a dose of 200 mg twice daily. 29
16
infected orphans (single or double orphaned) aged 2–14
years receiving NVP-based cART for at least 6 months, Statistical data analysis
accompanied by a parent or guardian who gave written
informed consent. Descriptive statistics for categorical sociodemographic
characteristics of participants such as orphan sex, orphan
status, HIV disclosure, caregiver age, caregiver marital status,
Data collection and study measurements caregiver relation to orphan, WHO status, caregiver self-
Nurse counsellors administered a pretested questionnaire to report and clinic attendance were described as frequencies
primary caregivers of the HIV-infected orphans which and proportions. For quantitative variables such as orphan
collected information on the sociodemographic and clinical age, caregiver age and NVP plasma concentrations, means

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