Table 3.
Selected studies evaluating the influence of CYP2C9 and/ or VKORC1 on attainment and maintenance of target INR among patients on coumarin therapy.
| Study Design | Polymorphisms assessed |
Time to Target INR | Time to Stable INR/ dose | Time in target range |
|---|---|---|---|---|
| ¤Retrospective cohort (n=561)39 | CYP2C9 *2, *3 | NE | NE | No difference |
| ¤Retrospective Cohort (n=186)40 | CYP2C9 *2, *3 | No difference | Longer in patients with variant CYP2C9 genotype |
NE |
| ψProspective cohort (n=284)74 | CYP2C9 *2, *3 | NE | Longer in patients with CYP2C9 *2 |
NE |
| ФProspective cohort (n=231)75 |
CYP2C9 *2, *3 CYP2C9 *3 allele |
NE | Longer in patients with | NE |
| ¤Nested Case Control (n=219)73 | CYP2C9 *2, *3 | NE | No difference | No difference |
| ФProspective cohort (n=231)56 |
CYP2C9 *2, *3 VKORC1-1173 |
NE | Longer in patients with CYP2C9 *3 allele |
NE |
| ψProspective cohort (n=281)57 |
CYP2C9 *2, *3 VKORC1-1173 |
NE | Longer in patients with CYP2C9 *2 |
NE |
| ¤Prospective cohort (n=317, 162 AA)32 |
CYP2C9 *2, *3 VKORC1-1173 |
NE | No difference | NE |
|
¤Prospective cohort (n=297, 29 AA)51 |
CYP2C9 *2, *3 VKORC1-1639, 1173, 1542, 2255 |
Shorter in patients with VKORC1 variant |
NE | NE VKORC1 variants spent more time above range during initiation |
|
¤Prospective cohort (302 EA, 273 AA)24 |
CYP2C9 *2, *3, *5, *6, *11 VKORC1-1173 |
No difference in EA or AA patients for CYP2C9 or VKORC1 |
No difference in EA or AA patients for CYP2C9 or VKORC1 |
NE |
All comparisons are presented for variant versus wild-type genotypes at a non-directional statistical significance of 0.05.
NE: Not evaluated or not reported, AA: African American; EA: European Americans
Study participations were on different coumarins: