TABLE 5.
Linear regression models for estimation of relative contributions of the variables studied to the variations in warfarin maintenance dose
Backward, P < 0.05 for variables to stay in the model.
| Regression Models | Variables Entered at the Beginning of Regression | Final Regression Equation | Model P Value | R2 |
|---|---|---|---|---|
| 1. All variables | Patient's demographic information,a SNPs known to affect warfarin dose,b SNPs in POR gene,c other concomitant medicationsd | SQRT(D) = 5.559 + 0.004 (weight) − 0.871 (CYP2C9*2) − 1.070 (CYP2C9*3) − 0.819 (VKORC1 −1639 A>G) + 0.379 (CYP4F2 rs2108622) + 0.355 (POR rs2868177) − 0.704 (POR −173C>A) − 0.510 (POR −208C>T) − 0.003 (aspirin) | <0.0001 | 0.477 |
| 2. Without other medications | Patient's demographic information,a SNPs known to affect warfarin dose,b SNPs in POR genec | SQRT(D) = 5.567 + 0.004 (weight) − 0.941 (CYP2C9*2) − 1.087 (CYP2C9*3) − 0.831 (VKORC1 −1639 A>G) + 0.312 (CYP4F2 rs2108622) + 0.357 (POR rs2868177) − 0.680 (POR −173C>A) − 0.556 (POR −208C>T) | <0.0001 | 0.457 |
| 3. Without other medications and POR SNPs | Patient's demographic information,a SNPs known to affect warfarin doseb | SQRT(D) = 5.650 + 0.005 (weight) − 0.869 (CYP2C9*2) − 1.091 (CYP2C9*3) − 0.751 (VKORC1 −1639 A>G) | <0.0001 | 0.395 |
a
Age, weight, and race.
b
CYP2C9*2, CYP2C9*3, VKORC1 −1639A>G, and CYP4F2 rs2108622.
c
POR A503V, rs10280802, rs28737229, rs1057870, rs17148944, rs2868177, −173C>A, and −208C>T.
d
Aspirin, amlodipine, multivitamin, insulin, and medicines containing statin.