Normal fat mass cannot be reliably estimated in typical pharmacokinetic studies.
Purpose: An influential covariate for pharmacokinetics is (body) size. Recently, the method of estimation of normal fat mass (NFM) has been advocated. Here, the relative contribution of fat mass, estimated as a fraction fat (Ffat), is used to explain differences in pharmacokinetic parameters. This c...
| Published in: | European Journal of Clinical Pharmacology Vol. 77; no. 5; pp. 727 - 734 |
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| Main Authors: | , , , , |
| Format: | equations & formulas research tables/charts Journal Article |
| Published: |
Springer Nature
May2021
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| Online Access: | View this record in EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=ccm&AN=149714815&site=ehost-live header: @attributes: shortDbName: ccm uiTerm: 149714815 longDbName: CINAHL Complete uiTag: AN controlInfo: bkinfo: dissinfo: jinfo: jid: 00316970 NP9 jtl: European Journal of Clinical Pharmacology issn: 00316970 maglogo: N pubinfo: dt: May2021 vid: 77 iid: 5 pid: 237 pub: Springer Nature place: New York, New York artinfo: ui: 149714815 147212097 149714815 149714815 10.1007/s00228-020-03042-4 149714815 ppf: 727 ppct: 7 formats: fmt: @attributes: type: P tig: atl: Normal fat mass cannot be reliably estimated in typical pharmacokinetic studies. aug: au: Wasmann, Roeland E. Svensson, Elin M. Schalkwijk, Stein J. Brüggemann, Roger J. ter Heine, Rob affil: Department of Pharmacy, Radboud Institute for Health Sciences, Radboud University Medical Center, Geert Grooteplein-Zuid 10, 6500 HB, Nijmegen, The Netherlands sug: subj: Adipose Tissue Body Size Drugs Pharmacokinetics Human Confidence Intervals Body Weight Models, Statistical Computer Simulation Drug Elimination Routes Fat Free Mass ab: Purpose: An influential covariate for pharmacokinetics is (body) size. Recently, the method of estimation of normal fat mass (NFM) has been advocated. Here, the relative contribution of fat mass, estimated as a fraction fat (Ffat), is used to explain differences in pharmacokinetic parameters. This concept is more and more applied. However, it remains unclear whether NFM can be reliably estimated in these typical studies. Methods: We performed an evaluation of the reliability of NFM estimation in a typical study size (n = 30), otherwise best-case scenario, by means of a pharmacokinetic simulation study. Several values of Ffat were investigated. Results: In a typical pharmacokinetic study, high imprecision was observed for NFM parameter estimates over a range of scenarios. For example, in a scenario where the true value of Ffat on clearance was 0.5, we found a 95% confidence interval of − 0.1 to 2.1, demonstrating a low precision. The implications for practice are that one could conclude that fat-free mass best describes the relationship of the pharmacokinetics with body size, while the true relationship was between fat-free mass and total body weight. Consequently, this could lead to incorrect extrapolation of pharmacokinetics to extreme body sizes. Conclusion: In typical pharmacokinetic studies, NFM should be used with caution because the Ffat estimates have low precision. The estimation of Ffat should always be preceded by careful study design evaluation before planning a study, to ensure that the design and sample size is sufficient to apply this potentially useful methodology. pubtype: Academic Journal doctype: equations & formulas research tables/charts Journal Article ougenre: Article language: English refInfo: holdings: @attributes: islocal: N |
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