Adherence to Drug-Refill Is a Useful Early Warning Indicator of Virologic and Immunologic Failure among HIV Patients on First-Line ART in South Africa

Abstract

BackgroundAffordable strategies to prevent treatment failure on first-line regimens among HIV patients are essential for the long-term success of antiretroviral therapy (ART) in sub-Saharan Africa. WHO recommends using routinely collected data such as adherence to drug-refill visits as early warning indicators. We examined the association between adherence to drug-refill visits and long-term virologic and immunologic failure among non-nucleoside reverse transcriptase inhibitor (NNRTI) recipients in South Africa.MethodsIn 2008, 456 patients on NNRTI-based ART for a median of 44 months (range 12–99 months; 1,510 person-years) were enrolled in a retrospective cohort study in Soweto. Charts were reviewed for clinical characteristics before and during ART. Multivariable logistic regression and Kaplan-Meier survival analysis assessed associations with virologic (two repeated VL>50 copies/ml) and immunologic failure (as defined by WHO).ResultsAfter a median of 15 months on ART, 19% (n = 88) and 19% (n = 87) had failed virologically and immunologically respectively. A cumulative adherence of <95% to drug-refill visits was significantly associated with both virologic and immunologic failure (p<0.01). In the final multivariable model, risk factors for virologic failure were incomplete adherence (OR 2.8, 95%CI 1.2–6.7), and previous exposure to single-dose nevirapine or any other antiretrovirals (adj. OR 2.1, 95%CI 1.2–3.9), adjusted for age and sex. In Kaplan-Meier analysis, the virologic failure rate by month 48 was 19% vs. 37% among adherent and non-adherent patients respectively (logrank p value = 0.02).ConclusionOne in five failed virologically after a median of 15 months on ART. Adherence to drug-refill visits works as an early warning indicator for both virologic and immunologic failure.

HIV/AIDS Treatment Failure and its Determinant Factors among First Line HAART Patients at Felege-Hiwot Referral Hospital, Bahir Dar, Northwest Ethiopia

“…In this study found that suboptimal drug adherence 9 times more risk of developing treatment failure than optimal adherence. This finding was concordant with study conducted in Kenya [18], South Africa [25] and In Gondar, Ethiopia [26].…”

“…In treatment failure, viral load criteria identified failure significantly earlier (median, 47.0 months; p<0.001) than did CD4 count criteria (median, 63.0 months).This study indicated that median time was higher when compared with the study conducted in South Africa 15 months [25], 24 months from Cameroon [24], 24 months from Gondar, Ethiopia [26] and 19.7 months from Addis Ababa, Ethiopia [27].…”

Adherence to antiretroviral therapy and factors affecting adherence among paediatric HIV patients

“…But poor adherence to ART is still seen leading to suboptimal ART regimens, resulting in rapid development of drug resistance. 4,5 Several methods have been developed for measurement of adherence that includes DOT (Directly observed therapy), therapeutic drug monitoring (TDM), medication event monitoring system (MEMS), self-report and Pill counts. 6 In pill count method, adherence is usually calculated by counting the remaining doses of medication and assuming that the remaining pills in excess of what is expected to represent missed doses.…”

Predictors of Nonadherence to Antiretroviral Therapy among HIV-Infected Adults in Dar es Salaam, Tanzania

“…8 In turn, adherence to medication and consistency with clinic visits has been shown to be significantly associated with improved clinical outcomes in patients living with HIV/AIDS in these settings. 8,[13][14][15][16] Consistent clinic attendance to a scheduled ART refill appointment has been suggested as a relatively easy way to identify nonadherent patients on ART over time in resource-poor settings. 13,16,17 In this study, we assessed the incidence of adherence to ART in a cohort of HIV-infected patients in a large urban Tanzanian HIV Care and Treatment program using adherence to clinic ART refill visits as a surrogate measure.…”