Regression Model for Predicting Warfarin Dose Using Pharmacogenetics

Description

Wells et al developed a regression model for predicting the dose of warfarin needed by a patient based on clinical data and genetic polymorphisms. The authors are from the University of Ottawa, Ottawa Hospital Research Institute and Children's Hospital of Eastern Ontario.

Maintenance warfarin doses in the study population ranged from 0.6 to 12 mg per day with a mean dose of 5.6 mg/day.

Exclusions: noncompliance, cirrhosis with Child-Pugh class II or III, CHF with NYHA Class >= 2

Parameters:

(1) age

(2) body mass index (BMI)

(3) height in centimeters, standardized (height minus mean height, which was 171.5

(4) exercise

(5) CYP2C9*2

(6) CYP2C9*3

(6) VKORC1 (1639)

(7) CYP4F2 (1347)

(8) therapy with angiotensin II receptor antagonist (losartan, candesartan)

(9) therapy with a beta-blocker (atenolol, bisaprolol, etc)

Parameter	Finding	Points
exercise	less	-0.73
	other	0
CYP2C9*2	none	0
	heterozygous	-1.12
	homozygous	-2.09
CYP2C9*3	heterozygous	-1.51
	other	0
VKORC1(1639)	AA homozygoous	-2.86
	GA heterozygous	-1.44
	GG homozygous	0
CYP4F2 (1347)	CC homozygous	-1.33
	CT heterozygous	-1.24
	TT heterozygous	0
angiotensin II receptor antagonist therapy	no	0
	yes	-1.46
beta-blocker therapy	no	0
	yes	-0.84

predicted warfarin maintenance dose in mg =

= 10.42 - (0.048 * (age in years)) + (0.041 * (BMI)) + (0.05 * ((height in cm) - 171.5)) + SUM(points for the remaining 7 parameters)

The final equation was adjusted by combining 10.42 and the adjustment for mean height (171.5) to generate 1.85:

10.42 - (0.05 * 171.5) = 1.85

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Description

Specialty

Objective

ICD-10

Regression Model of Wells et al for Predicting Warfarin Dose Using Pharmacogenetics

Purpose: To predict the maintenance dose of warfarin for a patient based on clinical and genetic polymorphisms.

Description

Specialty

Objective

ICD-10