Cox regression analysis for time to INR more than or equal to the lower limit of the therapeutic range and time to INR more than 4
| Covariate . | Time to INR within or above therapeutic range . | Time to INR > 4 . | ||||
|---|---|---|---|---|---|---|
| Hazard ratio . | 95% CI . | P . | Hazard ratio . | 95% CI . | P . | |
| Age | 1.00 | 0.99-1.01 | .76 | 1.02 | 1.00-1.04 | .023 |
| Male sex | 0.66 | 0.48-0.90 | .008 | 0.65 | 0.38-1.12 | .12 |
| White ethnicity | 0.70 | 0.40-1.23 | .22 | 0.70 | 0.25-1.93 | .49 |
| Target INR | 0.16 | 0.06-0.45 | < .001 | 8.20 | 1.23-54.8 | .030 |
| Amiodarone use | 0.96 | 0.61-1.51 | .87 | 1.01 | 0.49-2.06 | .98 |
| Cumulative warfarin dose* | 1.01 | 0.97-1.04 | .78 | 0.98 | 0.93-1.04 | .50 |
| INRearly | 3.34 | 2.67-4.18 | < .001 | 2.12 | 1.47-3.06 | < .001 |
| VKORC1 A haplotype | 1.64 | 1.29-2.11 | < .001 | 1.49 | 0.96-2.32 | .08 |
| CYP2C9, any variant | 1.10 | 0.84-1.44 | .48 | 1.01 | 0.61-1.67 | .97 |
| Covariate . | Time to INR within or above therapeutic range . | Time to INR > 4 . | ||||
|---|---|---|---|---|---|---|
| Hazard ratio . | 95% CI . | P . | Hazard ratio . | 95% CI . | P . | |
| Age | 1.00 | 0.99-1.01 | .76 | 1.02 | 1.00-1.04 | .023 |
| Male sex | 0.66 | 0.48-0.90 | .008 | 0.65 | 0.38-1.12 | .12 |
| White ethnicity | 0.70 | 0.40-1.23 | .22 | 0.70 | 0.25-1.93 | .49 |
| Target INR | 0.16 | 0.06-0.45 | < .001 | 8.20 | 1.23-54.8 | .030 |
| Amiodarone use | 0.96 | 0.61-1.51 | .87 | 1.01 | 0.49-2.06 | .98 |
| Cumulative warfarin dose* | 1.01 | 0.97-1.04 | .78 | 0.98 | 0.93-1.04 | .50 |
| INRearly | 3.34 | 2.67-4.18 | < .001 | 2.12 | 1.47-3.06 | < .001 |
| VKORC1 A haplotype | 1.64 | 1.29-2.11 | < .001 | 1.49 | 0.96-2.32 | .08 |
| CYP2C9, any variant | 1.10 | 0.84-1.44 | .48 | 1.01 | 0.61-1.67 | .97 |
n = 211 resulting from 3 missing genotypes.
INRearly indicates INR on days 4, 5, and 6 in 162, 27, and 25 patients, respectively.
In each patient, cumulative dose was calculated up to the day preceding the respective INR used in the analysis.