Frequencies of CYP2C9 genotypes in 561 patients with a mean maintenance warfarin dose of #1.5 mg compared to patients with a maintenance dose > 1.5 mg and in patients developing an INR > 8.0
| Genotype . | Maintenance dose ≤1.5 mg . | Maintenance dose > 1.5 mg . | Odds ratios compared to wild type . | Patients with INR of >8.0 . | Patients with INR < 8.0 on all occasions . | Odds ratios compared to wild type . |
|---|---|---|---|---|---|---|
| Wild type | 5 | 387 | 14 | 378 | ||
| 2C9*2 heterozygote | 7 | 100 | 5.42 (1.68-17.4) | 8 | 99 | 2.18 (0.89-5.35) |
| 2C9*2 homozygote | 0 | 3 | — | 0 | 3 | — |
| 2C9*3 heterozygote | 1 | 52 | 1.49 (0.17-13.0) | 1 | 52 | 0.52 (0.07-4.03) |
| 2C9*3 homozygote | 0 | 0 | — | 0 | 0 | — |
| 2C9*2*3 compound heterozygote | 0 | 6 | — | 0 | 6 | — |
| Genotype . | Maintenance dose ≤1.5 mg . | Maintenance dose > 1.5 mg . | Odds ratios compared to wild type . | Patients with INR of >8.0 . | Patients with INR < 8.0 on all occasions . | Odds ratios compared to wild type . |
|---|---|---|---|---|---|---|
| Wild type | 5 | 387 | 14 | 378 | ||
| 2C9*2 heterozygote | 7 | 100 | 5.42 (1.68-17.4) | 8 | 99 | 2.18 (0.89-5.35) |
| 2C9*2 homozygote | 0 | 3 | — | 0 | 3 | — |
| 2C9*3 heterozygote | 1 | 52 | 1.49 (0.17-13.0) | 1 | 52 | 0.52 (0.07-4.03) |
| 2C9*3 homozygote | 0 | 0 | — | 0 | 0 | — |
| 2C9*2*3 compound heterozygote | 0 | 6 | — | 0 | 6 | — |
Figures in parentheses are 95% confidence intervals for odds ratios.