PMID- 27461460 OWN - NLM STAT- MEDLINE DCOM- 20170927 LR - 20181113 IS - 1541-0420 (Electronic) IS - 0006-341X (Print) IS - 0006-341X (Linking) VI - 73 IP - 1 DP - 2017 Mar TI - Dynamic models for estimating the effect of HAART on CD4 in observational studies: Application to the Aquitaine Cohort and the Swiss HIV Cohort Study. PG - 294-304 LID - 10.1111/biom.12564 [doi] AB - Highly active antiretroviral therapy (HAART) has proved efficient in increasing CD4 counts in many randomized clinical trials. Because randomized trials have some limitations (e.g., short duration, highly selected subjects), it is interesting to assess the effect of treatments using observational studies. This is challenging because treatment is started preferentially in subjects with severe conditions. This general problem had been treated using Marginal Structural Models (MSM) relying on the counterfactual formulation. Another approach to causality is based on dynamical models. We present three discrete-time dynamic models based on linear increments models (LIM): the first one based on one difference equation for CD4 counts, the second with an equilibrium point, and the third based on a system of two difference equations, which allows jointly modeling CD4 counts and viral load. We also consider continuous-time models based on ordinary differential equations with non-linear mixed effects (ODE-NLME). These mechanistic models allow incorporating biological knowledge when available, which leads to increased statistical evidence for detecting treatment effect. Because inference in ODE-NLME is numerically challenging and requires specific methods and softwares, LIM are a valuable intermediary option in terms of consistency, precision, and complexity. We compare the different approaches in simulation and in illustration on the ANRS CO3 Aquitaine Cohort and the Swiss HIV Cohort Study. CI - (c) 2016, The International Biometric Society. FAU - Prague, Melanie AU - Prague M AD - Harvard T.H. Chan School of Public Health, Biostatistics Department, Boston, U.S.A. FAU - Commenges, Daniel AU - Commenges D AD - University of Bordeaux, ISPED, F-33000 Bordeaux, France. AD - INSERM, U1219 Bordeaux Population Health Research Centre, F-33000, Bordeaux, France. AD - INRIA (SISTM) Centre Recherche Bordeaux Sud-Ouest, University of Bordeaux, Talence, France. FAU - Gran, Jon Michael AU - Gran JM AD - Oslo Center for Biostatistics and Epidemiology, Oslo University Hospital and University of Oslo, Norway. FAU - Ledergerber, Bruno AU - Ledergerber B AD - Division of Infectious Diseases and Hospital Epidemiology, University Hospital of Zurich, Switzerland. FAU - Young, Jim AU - Young J AD - Basel Institute for Clinical Epidemiology and Biostatistics, University Hospital of Basel, Switzerland. FAU - Furrer, Hansjakob AU - Furrer H AD - Department of Infectious Diseases Bern University Hospital, University of Bern, Switzerland. FAU - Thiebaut, Rodolphe AU - Thiebaut R AD - University of Bordeaux, ISPED, F-33000 Bordeaux, France. AD - INSERM, U1219 Bordeaux Population Health Research Centre, F-33000, Bordeaux, France. AD - INRIA (SISTM) Centre Recherche Bordeaux Sud-Ouest, University of Bordeaux, Talence, France. LA - eng GR - R37 AI051164/AI/NIAID NIH HHS/United States PT - Journal Article PT - Research Support, N.I.H., Extramural DEP - 20160726 PL - England TA - Biometrics JT - Biometrics JID - 0370625 RN - 0 (Anti-HIV Agents) SB - IM MH - Anti-HIV Agents/*pharmacology MH - *Antiretroviral Therapy, Highly Active MH - *CD4 Lymphocyte Count MH - *Causality MH - Cohort Studies MH - Computer Simulation MH - Humans MH - *Linear Models MH - Observational Studies as Topic MH - Treatment Outcome MH - Viral Load PMC - PMC5269533 MID - NIHMS806270 OTO - NOTNLM OT - Dynamic mechanistic models OT - Linear increment models (LIM) OT - Marginal structural models (MSM) OT - Non-linear mixed effect models (NLME) OT - Observational study OT - Ordinary differential equation (ODE) EDAT- 2016/07/28 06:00 MHDA- 2017/09/28 06:00 PMCR- 2017/03/24 CRDT- 2016/07/28 06:00 PHST- 2015/07/01 00:00 [received] PHST- 2016/05/01 00:00 [revised] PHST- 2016/06/01 00:00 [accepted] PHST- 2016/07/28 06:00 [pubmed] PHST- 2017/09/28 06:00 [medline] PHST- 2016/07/28 06:00 [entrez] PHST- 2017/03/24 00:00 [pmc-release] AID - 10.1111/biom.12564 [doi] PST - ppublish SO - Biometrics. 2017 Mar;73(1):294-304. doi: 10.1111/biom.12564. Epub 2016 Jul 26.