Table 3.
Thrombophilia and coagulation abnormalities in all patients, those with patent fistula, and those with failure of primary fistula patency
| Thrombophilia and Coagulation Abnormalities | All Patients (n=219) | Patients with Patent Fistula (n=137) | Patients with Patency Failure (n=82) | P Valuea |
|---|---|---|---|---|
| Thrombophilia | ||||
| Factor V (R506Q) or prothrombin G20210A mutation | 8 (4) | 3 (2) | 5 (6) | 0.16 |
| Low protein S activity among 146 males (<58%)bc | 6 (4) | 3 (3) | 3 (7.5) | 0.35 |
| Low protein C activity (<74%)b | 7 (3) | 3 (2) | 4 (5) | 0.43 |
| Low antithrombin activity (≤60%) | 4 (2) | 0 | 4 (5) | 0.02d |
| Patients with above-mentioned thrombophiliae | 19 (9) | 8 (6) | 11 (13) | 0.05 |
| Positivity for antiphospholipid antibodiesf | 23 (11) | 15 (11) | 8 (10) | 0.78 |
| Coagulation abnormalities | ||||
| Short thrombin time (<17 s, 25th percentile) | 54 (26) | 36 (27) | 18 (23) | 0.49 |
| High factor VIII:c activity (>206%, 75th percentile) | 52 (24) | 32 (24) | 20 (25) | 0.92 |
| Low antithrombin activity (≤79%, 10th percentile) | 23 (11) | 13 (10) | 10 (12) | 0.53 |
| High fibrinogen level (>5.9 g/L, 75th percentile) | 47 (23) | 27 (21) | 20 (26) | 0.43 |
| High d-dimer level (>2.0 mg/L, 75th percentile) | 49 (23) | 33 (26) | 16 (20) | 0.36 |
| High homocysteine level (≥35 µmol/L, 75th percentile) | 51 (24) | 31 (24) | 20 (25) | 0.87 |
Values are expressed as number (percentage) of patients.
a
By chi-squared or Fisher exact test.
b
Warfarin users excluded from the analysis.
c
All female patients had normal protein S activity.
d
Statistically significant.
e
More than one type of thrombophilia was found in six patients.
f
Positivity for lupus anticoagulant, cardiolipin, or β2-glycoprotein I antibodies.