TY - JOUR
T1 - Short term adherence tool predicts failure on second line protease inhibitor-based antiretroviral therapy
T2 - An observational cohort study
AU - Court, Richard
AU - Leisegang, Rory
AU - Stewart, Annemie
AU - Sunpath, Henry
AU - Murphy, Richard
AU - Winternheimer, Philip
AU - Ally, Mashuda
AU - Maartens, Gary
N1 - Publisher Copyright:
© Court et al.; licensee BioMed Central Ltd.
PY - 2014/12/4
Y1 - 2014/12/4
N2 - Background: Most patients who experience virologic failure (VF) on second line antiretroviral therapy (ART) in low-middle income countries fail due to poor adherence rather than antiretroviral resistance. A simple adherence tool designed to detect VF would conserve resources by rationally limiting need for viral load (VL) testing and, in those countries with access to third line ART, the need for resistance testing. Methods: We conducted an observational cohort study of patients who initiated second line ART at a clinic in Kwazulu-Natal, South Africa. Using clinical and pharmacy refill data extracted from the clinic's electronic database, we determined risk factors for VF. Three different methods of calculating short term pharmacy refill adherence were evaluated and compared with long term adherence since second line initiation. We also explored the ability of differing durations of short term pharmacy refill to predict VF on second line ART. Results: We included 274 patients with a median follow up of 27months on second line ART. VF ranged between 3% and 16% within each six month interval after initiating second line ART. 243 patients with at least one VL after 4months on second line were analysed in the statistical analysis. Pharmacy refill adherence assessed over shorter periods (4 to 6months) predicted virologic suppression as well as pharmacy refill assessed over longer periods. The risk of VF fell 73% with each 10% increase in adherence measured from pharmacy refills over a 4month period. Low CD4 count at second line ART initiation was a significant independent risk factor for VF. Conclusion: Patients identified as poorly adherent by short term pharmacy refill are at risk for VF on second line ART. This pragmatic adherence tool could assist in identifying patients who require adherence interventions, and help rationalize use of VL monitoring and resistance testing among patients on second line ART.
AB - Background: Most patients who experience virologic failure (VF) on second line antiretroviral therapy (ART) in low-middle income countries fail due to poor adherence rather than antiretroviral resistance. A simple adherence tool designed to detect VF would conserve resources by rationally limiting need for viral load (VL) testing and, in those countries with access to third line ART, the need for resistance testing. Methods: We conducted an observational cohort study of patients who initiated second line ART at a clinic in Kwazulu-Natal, South Africa. Using clinical and pharmacy refill data extracted from the clinic's electronic database, we determined risk factors for VF. Three different methods of calculating short term pharmacy refill adherence were evaluated and compared with long term adherence since second line initiation. We also explored the ability of differing durations of short term pharmacy refill to predict VF on second line ART. Results: We included 274 patients with a median follow up of 27months on second line ART. VF ranged between 3% and 16% within each six month interval after initiating second line ART. 243 patients with at least one VL after 4months on second line were analysed in the statistical analysis. Pharmacy refill adherence assessed over shorter periods (4 to 6months) predicted virologic suppression as well as pharmacy refill assessed over longer periods. The risk of VF fell 73% with each 10% increase in adherence measured from pharmacy refills over a 4month period. Low CD4 count at second line ART initiation was a significant independent risk factor for VF. Conclusion: Patients identified as poorly adherent by short term pharmacy refill are at risk for VF on second line ART. This pragmatic adherence tool could assist in identifying patients who require adherence interventions, and help rationalize use of VL monitoring and resistance testing among patients on second line ART.
KW - HIV
KW - Medication adherence
KW - Pharmacy refill
KW - Second line antiretroviral therapy
KW - Virologic failure
UR - http://www.scopus.com/inward/record.url?scp=84923864472&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84923864472&partnerID=8YFLogxK
U2 - 10.1186/s12879-014-0664-3
DO - 10.1186/s12879-014-0664-3
M3 - Article
C2 - 25472544
AN - SCOPUS:84923864472
SN - 1471-2334
VL - 14
JO - BMC Infectious Diseases
JF - BMC Infectious Diseases
IS - 1
M1 - 664
ER -
