Variable | AF (N=106) n (%) | VTE (N=49) n (%) | p Value* |
---|---|---|---|
Number of measures reported (mean±SD) | 2.36±1.44 | 1.53±0.92 | <0.001 |
1 | 39 (36.8) | 31 (63.3) | |
2 | 30 (28.3) | 13 (26.5) | |
3 | 13 (12.3) | 4 (8.2) | |
4 | 13 (12.3) | 0 | |
5 | 8 (7.5) | 0 | |
6 | 2 (1.9) | 1 (2.0) | |
7 | 1 (0.9) | 0 | |
≥2 | 67 (63.2) | 18 (36.7) | 0.004 |
Percentage of time in range (INR=2–3) | 87 (82.1) | 36 (73.5) | 0.31 |
Below range (<2) | 53 (50.0) | 25 (51.0) | 0.96 |
Above range (>3) | 54 (51.0) | 24 (49.0) | 0.96 |
In extended range (1.8–3.2) | 15 (14.2) | 0 | 0.01 |
In extreme range (<1.5, >5) | 13 (12.3) | 6 (12.2) | 0.80 |
Proportion of INR tests in range (INR=2–3) | 18 (17.0) | 7 (14.3) | 0.85 |
Below range (<2) | 16 (15.1) | 7 (14.3) | 0.91 |
Above range (>3) | 14 (13.2) | 7 (14.3) | 0.94 |
In extreme range (<1.5, >4) | 11 (10.4) | 0 | 0.05 |
Mean/median INR | 30 (28.3) | 8 (16.3) | 0.16 |
Mean/median VKA dose | 15 (14.2) | 3 (6.1) | 0.24 |
Frequency of INR monitoring | 32 (30.2) | 7 (14.3) | 0.06 |
INR variability | 8 (7.5) | 0 | 0.11 |
INR testing interval | 29 (27.4) | 4 (8.2) | 0.01 |
Proportion of patients in/out of range† | 20 (18.9) | 9 (18.4) | 0.88 |
Other‡ | 11 (10.4) | 2 (4.1) | 0.32 |
*p Value for the comparison of AF vs VTE.
†For example, point prevalence, proportion of patients in range >50% of time or proportion of patients with ≥50% of INR measures <3.0.
‡Other measures include: number of dosage changes; INR measure after a previously subtherapeutic or supratherapeutic INR; proportion of patients with ≥1INR measure below range after reaching an adequate INR; number of days until the next INR measure after an extreme measure; proportion of days with treatment stability (two consecutive INR measures in range); days to reach a therapeutic INR; mean time until stable (6 months within target INR range); minimum and maximum INR values per patient.
AF, atrial fibrillation; INR, international normalised ratio; VKA, vitamin K antagonist; VTE, venous thromboembolism.