Table 2

Characteristics of the patients according to rate of normalization of prothrombin time, and warfarin therapy

Characteristics
Normal
Slow
All
Uni-variable p-value
Multi-variable p-value

N
188
14
202


Sex, males (%)
136(72)
11(79)
147(73)
n.s.

Age, y*

69.1(± 10.8)
(36–89)
73.4(± 13.2)
(48–93)
69.4(± 11.0)
(36–93)
0.16

0.49

BMI*

29.2(± 5.5)
(17.1–55.1)
29.0(± 4.3)
(22.2–40.1)
29.2(± 5.4)
(17.1–55.1)
n.s


Weekly warfarin dose, mg*

29.7(± 12.3)
(6.25–77)
23.2(± 13.7)
(8.75–57.5)
29.3(± 12.4)
(6.25–77)
0.06

0.20

Baseline INR*
2.6(± 0.5) (2.0–4.2)
3.2(± 0.6) (2.1–4.3)
2.7(± 0.5) (2.0–4.3)
0.0004
0.0021
Day of last dose warfarin* (in relation to surgery)
-6.1(± 0.5) (-8 – -5)
-6.1(± 0.3) (-7 – -6)
-6.1(± 0.5)
n.s.

Pre-operative creatinine, μmol/L*
104(± 34) (49–336)
120(± 41) (65–196)
105(± 35) (49–336)
0.09
0.40
Known liver disease (%)
7(3.7)
1(7.1)
8(4.0)
n.s.

Medication interaction score*
1.5(± 1.3) (-1 – 5)
1.4(± 1.4) (0–4)
1.5(± 1.3) (-1 – 5)
n.s.

Number of concomitant drugs*
7 (± 3) (0–14)
8 (± 3) (4–16)
7 (± 3) (0–16)
n.s.

Amiodarone medication (%)
29(15)
2(14)
31(15)
n.s.

Thyroid hormone treatment (%)
21(11)
2(14)
23(11)
n.s.


Schulman et al. Thrombosis Journal 2008 6:15   doi:10.1186/1477-9560-6-15