Table 1.
Subject Characteristics.
| Tucson, AZ | San Juan, PR | P-valuea | |
|---|---|---|---|
| Participants (n) | 141 | 96 | |
| Warfarin dose (mg/week) (mean (SD)) | 33.84 (15.67) | 32.25 (11.64) | 0.397 |
| BSA (m2) | 1.90 (0.31) | 2.01 (0.22) | 0.004 |
| Age (years) | 62.77 (16.75) | 69.18 (10.00) | 0.001 |
| Male Gender (n (%)) | 81 (57.4) | 95 (99.0) | <0.001 |
| European Global Ancestry b | 0.60 (0.12) | 0.76 (0.11) | <0.001 |
| Amiodarone Users | 6 (4.3) | 1 (1.0) | 0.297 |
| Enzyme Inducer Users c | 5 (3.5) | 1 (1.0) | 0.433 |
| CYP2C9 Intermediate Metabolizer d | 26 (18.8) | 20 (20.8) | 0.834 |
| VKORC1e (%) | <0.001 | ||
| G/G | 28 (19.9) | 38 (39.6) | |
| G/A | 74 (52.5) | 45 (46.9) | |
| A/A | 39 (27.7) | 13 (13.5) |
Hypotheses were tested with chi-square goodness of fit test for equal counts for categorical variables using chisq.test() and t-test for continuous variables with oneway.test() using the tableone package in R
European ancestry was derived using individuals from the Iberian Peninsula as reference
Enzyme Inducers surveyed include: phenytoin, carbamazepine, rifampin and rifampicin
rs1799853 and rs1057910 were surveyed to proxy CYP2C9*2 and *3. Metabolizer status was derived following the current Clinical Pharmacogenetics Implementation Consortium Guideline for Warfarin. No participants in either cohort carried CYP2C9 variants on both alleles, thus there are no poor metabolizers to report.
VKORC1-1639G>A (rs9923231) was surveyed to proxy metabolizer status at VKORC1
AZ indicates Arizona; PR, Puerto Rico; mg, milligrams; SD, standard deviation; BSA, body surface area; m2, meters squared; CYP2C9, Cytochrome P450 family 2 subfamily C member 9; VKORC1, Vitamin K epoxide Reductase Complex subunit 1