Imperial College London
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DrAnneCori

Faculty of Medicine, School of Public Health

Senior Lecturer in Infectious Disease Modelling
 
 
 
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Contact

 

+44 (0)20 7594 3229a.cori

 
 
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Location

 

404School of Public HealthWhite City Campus

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Summary

 

Publications

Citation

BibTex format

@article{Cori:2015:10.1097/QAD.0000000000000854,
author = {Cori, A and Pickles, M and van, Sighem A and Gras, L and Bezemer, D and Reiss, P and Fraser, C},
doi = {10.1097/QAD.0000000000000854},
journal = {AIDS},
pages = {2435--2446},
title = {CD4+ cell dynamics in untreated HIV-1 infection: overall rates, and effects of age, viral load, sex and calendar time.},
url = {http://dx.doi.org/10.1097/QAD.0000000000000854},
volume = {29},
year = {2015}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - BACKGROUND: CD4 cell count is a key measure of HIV disease progression, and the basis of successive international guidelines for treatment initiation. CD4 cell dynamics are used in mathematical and econometric models for evaluating public health need and interventions. Here, we estimate rates of CD4 decline, stratified by relevant covariates, in a form that is clinically transparent and can be directly used in such models. METHODS: We analyse the AIDS Therapy Evaluation in the Netherlands cohort, including individuals with date of seroconversion estimated to be within 1 year and with intensive clinical follow-up prior to treatment initiation. Owing to the fact that CD4 cell counts are intrinsically noisy, we separate the analysis into long-term trends of smoothed CD4 cell counts and an observation model relating actual CD4 measurements to the underlying smoothed counts. We use a monotonic spline smoothing model to describe the decline of smoothed CD4 cell counts through categories CD4 above 500, 350-500, 200-350 and 200cells/μl or less. We estimate the proportion of individuals starting in each category after seroconversion and the average time spent in each category. We examine individual-level cofactors which influence these parameters. RESULTS: Among untreated individuals, the time spent in each compartment was 3.32, 2.70, 5.50 and 5.06 years. Only 76% started in the CD4 cell count above 500cells/μl compartment after seroconversion. Set-point viral load (SPVL) was an important factor: individuals with at least 5 log10copies/ml took 5.37 years to reach CD4 cell count less than 200cells/μl compared with 15.76 years for SPVL less than 4 log10copies/ml. CONCLUSION: Many individuals already have CD4 cell count below 500cells/μl after seroconversion. SPVL strongly influences the rate of CD4 decline. Treatment guidelines should consider measuring SPVL, whereas mathematical models should incorporate SPVL stratification.
AU  - Cori,A
AU  - Pickles,M
AU  - van,Sighem A
AU  - Gras,L
AU  - Bezemer,D
AU  - Reiss,P
AU  - Fraser,C
DO  - 10.1097/QAD.0000000000000854
EP  - 2446
PY  - 2015///
SN  - 0269-9370
SP  - 2435
TI  - CD4+ cell dynamics in untreated HIV-1 infection: overall rates, and effects of age, viral load, sex and calendar time.
T2  - AIDS
UR  - http://dx.doi.org/10.1097/QAD.0000000000000854
UR  - http://hdl.handle.net/10044/1/28178
VL  - 29
ER  -
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