TY - JOUR
T1 - A simple, dynamic measure of antiretroviral therapy adherence predicts failure to maintain HIV-1 suppression
AU - Gross, Robert
AU - Yip, Benita
AU - Lo Re, Vincent
AU - Wood, Evan
AU - Alexander, Christopher S.
AU - Harrigan, P. Richard
AU - Bangsberg, David R.
AU - Montaner, Julio S.G.
AU - Hogg, Robert S.
N1 - Funding Information:
Financial support: Michael Smith Foundation for Health Research (Senior Scholar Award to R.S.H.); Canadian Institutes of Health Research (peer-reviewed grant); National Institutes of Health (research grant K08-MH01584 to R.G.); University of Pennsylvania AIDS Clinical Trials Unit (grant U01-AI32783 to R.G.); University of Pennsylvania Center for AIDS Research (grant P30-AI45008 to R.G.); Agency for Healthcare Research and Quality Centers for Education and Research on Therapeutics (cooperative agreement grant HS10399 to R.G.).
PY - 2006/10/15
Y1 - 2006/10/15
N2 - Background. High levels of antiretroviral therapy adherence are important for human immunodeficiency virus type 1 (HIV-1) suppression, yet the magnitude of adherence required to maintain it is less well characterized. Furthermore, methods to accommodate changes in adherence over time are lacking. In the present study, our objective was to determine the magnitude of antiretroviral therapy adherence needed to maintain HIV-1 suppression by use of a time-updated adherence measure that has the potential to be of use in a clinical setting. Methods. We examined a population-based cohort of HIV-1-infected subjects ≥18 years of age, residing in British Columbia, Canada, who started receiving antiretroviral therapy between 1 August 1996 and 30 September 2003, who had at least 2 consecutive viral loads <500 copies/mL and who had prescriptions filled at least 3 times during a follow-up period ending 30 September 2004. Virological failure was defined as the second of 2 consecutive viral loads >1000 copies/mL. Cox proportional hazards model was used to determine the relationship between virological failure and refill-based, time-updated surrogate measure of adherence. Results. Among the 1634 participants ≥18 years of age who initiated triple combination therapy during the study, 606 virological failure events were identified. In multivariate analyses, subjects with ≤95% adherence were 1.66 (95% confidence interval, 1.38-2.01) times more likely to experience virological failure than those with >95% adherence. Conclusions. The highest levels of antiretroviral therapy adherence are associated with higher rates of maintained virological suppression. This simple, dynamic surrogate measure of adherence overcomes the limitation of single-point-in-time calculations of adherence and may be useful in real time to determine whether an individual is exhibiting incomplete adherence.
AB - Background. High levels of antiretroviral therapy adherence are important for human immunodeficiency virus type 1 (HIV-1) suppression, yet the magnitude of adherence required to maintain it is less well characterized. Furthermore, methods to accommodate changes in adherence over time are lacking. In the present study, our objective was to determine the magnitude of antiretroviral therapy adherence needed to maintain HIV-1 suppression by use of a time-updated adherence measure that has the potential to be of use in a clinical setting. Methods. We examined a population-based cohort of HIV-1-infected subjects ≥18 years of age, residing in British Columbia, Canada, who started receiving antiretroviral therapy between 1 August 1996 and 30 September 2003, who had at least 2 consecutive viral loads <500 copies/mL and who had prescriptions filled at least 3 times during a follow-up period ending 30 September 2004. Virological failure was defined as the second of 2 consecutive viral loads >1000 copies/mL. Cox proportional hazards model was used to determine the relationship between virological failure and refill-based, time-updated surrogate measure of adherence. Results. Among the 1634 participants ≥18 years of age who initiated triple combination therapy during the study, 606 virological failure events were identified. In multivariate analyses, subjects with ≤95% adherence were 1.66 (95% confidence interval, 1.38-2.01) times more likely to experience virological failure than those with >95% adherence. Conclusions. The highest levels of antiretroviral therapy adherence are associated with higher rates of maintained virological suppression. This simple, dynamic surrogate measure of adherence overcomes the limitation of single-point-in-time calculations of adherence and may be useful in real time to determine whether an individual is exhibiting incomplete adherence.
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U2 - 10.1086/507680
DO - 10.1086/507680
M3 - Article
C2 - 16991085
AN - SCOPUS:33749641642
SN - 0022-1899
VL - 194
SP - 1108
EP - 1114
JO - Journal of Infectious Diseases
JF - Journal of Infectious Diseases
IS - 8
ER -