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Application of Akaike information criterion to evaluate warfarin dosing algorithm
Takumi Harada1, Noritaka Ariyoshi, Hitoshi Shimura
1Laboratory of Clinical Pharmacology, Graduate School of Pharmaceutical Sciences, Chiba University, University Hospital, Department of Cardiovascular Surgery, Chiba, Japan.
Thrombosis Research
|June 18, 2010
Summary
New factors like white blood-cell count and CYP4F2 genotype improve warfarin dosing. The Akaike Information Criterion (AIC) offers a simple method to evaluate these factors for better warfarin maintenance dose prediction.
Area of Science:
- Pharmacogenomics
- Clinical Pharmacology
- Biostatistics
Background:
- Inter-individual variability in warfarin response is significant.
- Unidentified factors continue to influence warfarin dosing accuracy.
- Existing dosing algorithms require refinement for improved patient outcomes.
Purpose of the Study:
- To investigate novel variables for enhancing warfarin dosing algorithms.
- To assess the utility of the Akaike Information Criterion (AIC) for evaluating potential dosing factors.
- To identify simple methods for improving warfarin dose prediction.
Main Methods:
- Japanese patient cohort utilized for analysis.
- Genotyping of specific genes (e.g., CYP4F2, VKORC1) performed.
- Multivariate linear regression analyses constructed dosing algorithms.
- Akaike Information Criterion (AIC) used for model evaluation.
Main Results:
- White blood-cell count (WBC), allopurinol use, and CYP4F2 genotype identified as significant factors in warfarin dose variation.
- Inclusion of these factors alongside age and VKORC1 genotype decreased AIC values.
- Demonstrated a potential improvement in predicting warfarin maintenance dose.
Conclusions:
- WBC, allopurinol, and CYP4F2 genotype are valuable additions to warfarin dosing algorithms.
- AIC serves as an effective and straightforward tool for evaluating model fit and factor inclusion.
- This study pioneers the use of AIC for warfarin dosing algorithm assessment, offering a pathway for enhanced clinical practice.
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