Table 2. Risk factors for bleeding in patients with elevated international normalized ratio: No vitamin K therapy received versus vitamin K received.
| Risk factors | No vitamin K (n = 34) | Vitamin K (n = 17) |
|---|---|---|
| Past medical history, n (%) | ||
| Renal insufficiency | 12 (35) | 10 (59) |
| ASA/NSAID use | 7 (21) | 5 (29) |
| History of stroke/TIA | 5 (15) | 0 (0) |
| Hepatic insufficiency | 4 (12) | 1 (6) |
| Malignancy | 4 (12) | 6 (35) |
| History of GI bleed | 1 (3) | 2 (12) |
| Warfarin weekly dose, mg, mean± SD | 38± 19 | 24± 8 |
Note: ASA = acetylsalicylic acid; GI = gastrointestinal; NSAID = nonsteroidal anti-inflammatory drug; TIA = transient ischemic attack. P > .05 using chi-square test for categorical variables and Mann-Whitney U test for continuous data.