Which adherence measure - self-report, clinician recorded or pharmacy refill - is best able to predict detectable viral load in a public ART programme without routine plasma viral load monitoring?
Combination antiretroviral therapy (cART) suppresses viral replication to an undetectable level if a sufficiently high level of adherence is achieved. We investigated which adherence measurement best distinguishes between patients with and without detectable viral load in a public ART programme without routine plasma viral load monitoring.



We randomly selected 870 patients who started cART between May 2009 and April 2012 in 10 healthcare facilities in Addis Ababa, Ethiopia. Six hundred and sixty-four (76.3%) patients who were retained in HIV care and were receiving cART for at least 6 months were included and 642 had their plasma HIV-1 RNA concentration measured. Patients' adherence to cART was assessed according to self-report, clinician recorded and pharmacy refill measures. Multivariate logistic regression model was fitted to identify the predictors of detectable viremia. Model accuracy was evaluated by computing the area under the receiver operating characteristic (ROC) curve.



A total of 9.2% and 5.5% of the 642 patients had a detectable viral load of ≥40 and ≥400 RNA copies/ml, respectively. In the multivariate analyses, younger age, lower CD4 cell count at cART initiation, being illiterate and widowed, and each of the adherence measures were significantly and independently predictive of having ≥400 RNA copies/ml. The ROC curve showed that these variables altogether had a likelihood of more than 80% to distinguish patients with a plasma viral load of ≥400 RNA copies/ml from those without.



Adherence to cART was remarkably high. Self-report, clinician recorded and pharmacy refill non-adherence were all significantly predictive of detectable viremia. The choice for one of these methods to detect non-adherence and predict a detectable viral load can therefore be based on what is most practical in a particular setting.
Department of Medical Psychology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.|Department of Epidemiology, Netherlands Institute for Health Sciences/Erasmus University Medical Center, Rotterdam, The Netherlands.|School of Public Health, Addis Ababa University, Addis Ababa, Ethiopia.|Division of Infectious Diseases, Department of Internal Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
Legese A
LA
Mekuria
Division of Infectious Diseases, Department of Internal Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
Jan M
JM
Prins
School of Public Health, Addis Ababa University, Addis Ababa, Ethiopia.
Alemayehu W
AW
Yalew
Department of Medical Psychology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
Mirjam A G
MA
Sprangers
Department of Medical Psychology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
Pythia T
PT
Nieuwkerk
D000328:Adult; D019380:Anti-HIV Agents / Q000627:therapeutic use; D023241:Antiretroviral Therapy, Highly Active; D018791:CD4 Lymphocyte Count; D005260:Female; D015658:HIV Infections / Q000188:drug therapy*; D006801:Humans; D008297:Male; D008499:Medical Records; D055118:Medication Adherence; D008875:Middle Aged; D010593:Pharmaceutical Services; D010594:Pharmacies; D010820:Physicians; D057566:Self Report; D019562:Viral Load
D019380:Anti-HIV Agents
Adherencia; HIV/AIDS; TARc; VIH/SIDA; adherence; adhésion; cART; cadre à ressources limitées; carga viral detectable; charge virale détectable; combination antiretroviral therapy; detectable viral load; emplazamiento con recursos limitados; resource-limited setting