Viral load versus CD4⁺ monitoring and 5-year outcomes of antiretroviral therapy in HIV-positive children in Southern Africa: a cohort-based modelling study.
OBJECTIVE
Many paediatric antiretroviral therapy (ART) programmes in Southern Africa rely on CD4⁺ to monitor ART. We assessed the benefit of replacing CD4⁺ by viral load monitoring.


METHODS
A mathematical modelling study.


METHODS
A simulation model of HIV progression over 5 years in children on ART, parameterized by data from seven South African cohorts. We simulated treatment programmes with 6-monthly CD4⁺ or 6- or 12-monthly viral load monitoring. We compared mortality, second-line ART use, immunological failure and time spent on failing ART. In further analyses, we varied the rate of virological failure, and assumed that the rate is higher with CD4⁺ than with viral load monitoring.


RESULTS
About 7% of children were predicted to die within 5 years, independent of the monitoring strategy. Compared with CD4⁺ monitoring, 12-monthly viral load monitoring reduced the 5-year risk of immunological failure from 1.6 to 1.0% and the mean time spent on failing ART from 6.6 to 3.6 months; 1% of children with CD4⁺ compared with 12% with viral load monitoring switched to second-line ART. Differences became larger when assuming higher rates of virological failure. When assuming higher virological failure rates with CD4⁺ than with viral load monitoring, up to 4.2% of children with CD4⁺ compared with 1.5% with viral load monitoring experienced immunological failure; the mean time spent on failing ART was 27.3 months with CD4⁺ monitoring and 6.0 months with viral load monitoring. Conclusion: Viral load monitoring did not affect 5-year mortality, but reduced time on failing ART, improved immunological response and increased switching to second-line ART.
Luisa
L
Salazar-Vizcaya
Olivia
O
Keiser
Karl Technau
Mary-Ann
MA
Davies
Andreas D
AD
Haas
Nello
N
Blaser
Vivian
V
Cox
Brian
B
Eley
Helena
H
Rabie
Harry
H
Moultrie
Janet
J
Giddy
Robin
R
Wood
Matthias
M
Egger
Janne
J
Estill
D000293:Adolescent; D000353:Africa, Southern; D044966:Anti-Retroviral Agents / Q000627:therapeutic use*; D018791:CD4 Lymphocyte Count; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D016903:Drug Monitoring / Q000379:methods*; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000276:immunology / Q000821:virology; D006801:Humans; D007223:Infant; D008297:Male; D008962:Models, Theoretical; D016019:Survival Analysis; D016896:Treatment Outcome; D019562:Viral Load
D044966:Anti-Retroviral Agents