Characteristics of study population
Characteristic . | Patients with access thrombosis . | Controls . | P . |
|---|---|---|---|
| N | 107 | 309 | |
| Age, y, mean ± SD | 60.6 ± 17.2 | 64.8 ± 16.0 | .023 |
| Female, no. (%) | 46 (43) | 112 (36.2) | .215 |
| Race, no. (%) | .176 | ||
| White | 90 (84.1) | 271 (87.7) | |
| Black | 10 (9.3) | 14 (4.5) | |
| Other | 7 (6.5) | 24 (7.8) | |
| Weight, kg, mean ± SD | 72.1 ± 18.9 | 72.4 ± 17.8 | .912 |
| Body mass index, mean ± SD | 25.5 ± 6.4 | 25.7 ± 5.6 | .856 |
| Medical history, no. (%) | |||
| Peripheral vascular disease | 29 (27.1) | 95 (30.7) | .478 |
| Coronary artery disease | 42 (39.3) | 114 (36.9) | .664 |
| Stroke or transient ischemic attack | 8 (7.5) | 45 (14.6) | .058 |
| Malignancy | 23 (21.5) | 51 (16.5) | .245 |
| Venous thromboembolism | 7 (6.5) | 12 (3.9) | .284 |
| Diabetes | 30 (28.0) | 104 (33.7) | .284 |
| Cause of end-stage renal disease, no. (%) | .379 | ||
| Diabetes | 18 (16.8) | 72 (23.3) | |
| Glomerulonephritis | 24 (22.4) | 62 (20.1) | |
| Hypertension | 12 (11.2) | 47 (15.2) | |
| Polycystic kidney disease | 8 (7.5) | 25 (8.1) | |
| Urinary obstruction/reflux | 9 (8.4) | 13 (4.2) | |
| Unknown | 16 (15.0) | 44 (14.2) | |
| Other | 20 (18.7) | 46 (14.9) | |
| Smoking tobacco use, no. (%) | .261 | ||
| Never | 34 (31.8) | 100 (32.4) | |
| Former | 48 (44.9) | 158 (51.1) | |
| Current | 25 (23.4) | 51 (16.5) | |
| Medications, no. (%) | |||
| Angiotensin converting enzyme inhibitor | 32 (29.9) | 123 (39.8) | .068 |
| Warfarin | 22 (20.6) | 41 (13.3) | .070 |
| Antiplatelet agent | 41 (38.3) | 130 (42.1) | .496 |
| Hormone replacement therapy or birth control pill | 8 (7.5) | 19 (6.1) | .631 |
| Vitamin B12, B6, folic acid, or multivitamin | 81 (75.7) | 257 (83.2) | .088 |
| Family history of venous thromboembolism, no. (%) | 4 (3.7) | 14 (4.5) | > .999 |
| Type of dialysis access, no. (%) | < .001 | ||
| Arteriovenous fistula | 81 (75.7) | 299 (96.8) | |
| Arteriovenous graft | 26 (24.3) | 10 (3.2) | |
| Location of dialysis access, no. (%) | .003 | ||
| Lower arm | 66 (61.7) | 151 (48.9) | |
| Upper arm | 38 (35.5) | 157 (50.8) | |
| Leg | 3 (2.8) | 1 (0.3) | |
| Median time from access surgery to first cannulation, d | 56.5 | 56.0 | .709 |
| Median time from access surgery to thrombosis or end of observation period, d | 548.0 | 1037.0 | < .001 |
| Dialysis access angiogram performed, no. (%) | 56 (52.3) | 185 (59.9) | .174 |
| Dialysis access angioplasty or surgical revision performed, no. (%) | 50 (46.7) | 130 (42.1) | .402 |
| Previous dialysis access created but never functioned, no. (%) | 29 (27.1) | 59 (19.1) | .080 |
| Hemoglobin level, g/L, mean ± SD | 116 ± 11 | 118 ± 11 | .084 |
| Erythropoietin dose, U/wk, mean ± SD | 12 104 ± 7567 | 12 353 ± 9107 | .800 |
| Albumin level, g/L, mean ± SD | 37 ± 5 | 36 ± 5 | .022 |
| Urea reduction ratio, mean ± SD | 73 ± 7 | 76 ± 6 | < .001 |
| Thrombophilia, no. (%) | |||
| Factor V Leiden | 7 (6.5) | 6 (1.9) | .046 |
| Prothrombin gene mutation 20210G > A | 3 (2.8) | 9 (2.9) | > .999 |
| Anticardiolipin antibodies (IgG) at least 30 GPL U/mL | 2 (1.9) | 5 (1.6) | > .999 |
| Anticardiolipin antibodies (IgM) at least 30 MPL U/mL | 2 (1.9) | 8 (2.6) | > .999 |
| Lupus anticoagulant | 2 (1.9) | 8 (2.6) | > .999 |
| Factor VIII level greater than 90th percentile* | 18 (16.8) | 30 (9.7) | .047 |
| Homocysteine at least at 85th percentile† | 22 (20.6) | 40 (12.9) | .057 |
| Lipoprotein(a) at least at 85th percentile‡ | 23 (21.5) | 41 (13.3) | .042 |
| Presence of any thrombophilia | 59 (55.1) | 121 (39.2) | .004 |
| TGF-β1 production haplotype, no. (%) | .006 | ||
| High producers | 69 (64.5) | 232 (75.1) | |
| Intermediate producers | 28 (26.2) | 69 (22.3) | |
| Low producers | 10 (9.3) | 8 (2.6) | |
| PAI-1 genotype, no. (%) | .552 | ||
| 4G/4G | 24 (22.4) | 75 (24.3) | |
| 4G/5G | 60 (56.1) | 155 (50.2) | |
| 5G/5G | 23 (21.5) | 79 (25.6) |
Characteristic . | Patients with access thrombosis . | Controls . | P . |
|---|---|---|---|
| N | 107 | 309 | |
| Age, y, mean ± SD | 60.6 ± 17.2 | 64.8 ± 16.0 | .023 |
| Female, no. (%) | 46 (43) | 112 (36.2) | .215 |
| Race, no. (%) | .176 | ||
| White | 90 (84.1) | 271 (87.7) | |
| Black | 10 (9.3) | 14 (4.5) | |
| Other | 7 (6.5) | 24 (7.8) | |
| Weight, kg, mean ± SD | 72.1 ± 18.9 | 72.4 ± 17.8 | .912 |
| Body mass index, mean ± SD | 25.5 ± 6.4 | 25.7 ± 5.6 | .856 |
| Medical history, no. (%) | |||
| Peripheral vascular disease | 29 (27.1) | 95 (30.7) | .478 |
| Coronary artery disease | 42 (39.3) | 114 (36.9) | .664 |
| Stroke or transient ischemic attack | 8 (7.5) | 45 (14.6) | .058 |
| Malignancy | 23 (21.5) | 51 (16.5) | .245 |
| Venous thromboembolism | 7 (6.5) | 12 (3.9) | .284 |
| Diabetes | 30 (28.0) | 104 (33.7) | .284 |
| Cause of end-stage renal disease, no. (%) | .379 | ||
| Diabetes | 18 (16.8) | 72 (23.3) | |
| Glomerulonephritis | 24 (22.4) | 62 (20.1) | |
| Hypertension | 12 (11.2) | 47 (15.2) | |
| Polycystic kidney disease | 8 (7.5) | 25 (8.1) | |
| Urinary obstruction/reflux | 9 (8.4) | 13 (4.2) | |
| Unknown | 16 (15.0) | 44 (14.2) | |
| Other | 20 (18.7) | 46 (14.9) | |
| Smoking tobacco use, no. (%) | .261 | ||
| Never | 34 (31.8) | 100 (32.4) | |
| Former | 48 (44.9) | 158 (51.1) | |
| Current | 25 (23.4) | 51 (16.5) | |
| Medications, no. (%) | |||
| Angiotensin converting enzyme inhibitor | 32 (29.9) | 123 (39.8) | .068 |
| Warfarin | 22 (20.6) | 41 (13.3) | .070 |
| Antiplatelet agent | 41 (38.3) | 130 (42.1) | .496 |
| Hormone replacement therapy or birth control pill | 8 (7.5) | 19 (6.1) | .631 |
| Vitamin B12, B6, folic acid, or multivitamin | 81 (75.7) | 257 (83.2) | .088 |
| Family history of venous thromboembolism, no. (%) | 4 (3.7) | 14 (4.5) | > .999 |
| Type of dialysis access, no. (%) | < .001 | ||
| Arteriovenous fistula | 81 (75.7) | 299 (96.8) | |
| Arteriovenous graft | 26 (24.3) | 10 (3.2) | |
| Location of dialysis access, no. (%) | .003 | ||
| Lower arm | 66 (61.7) | 151 (48.9) | |
| Upper arm | 38 (35.5) | 157 (50.8) | |
| Leg | 3 (2.8) | 1 (0.3) | |
| Median time from access surgery to first cannulation, d | 56.5 | 56.0 | .709 |
| Median time from access surgery to thrombosis or end of observation period, d | 548.0 | 1037.0 | < .001 |
| Dialysis access angiogram performed, no. (%) | 56 (52.3) | 185 (59.9) | .174 |
| Dialysis access angioplasty or surgical revision performed, no. (%) | 50 (46.7) | 130 (42.1) | .402 |
| Previous dialysis access created but never functioned, no. (%) | 29 (27.1) | 59 (19.1) | .080 |
| Hemoglobin level, g/L, mean ± SD | 116 ± 11 | 118 ± 11 | .084 |
| Erythropoietin dose, U/wk, mean ± SD | 12 104 ± 7567 | 12 353 ± 9107 | .800 |
| Albumin level, g/L, mean ± SD | 37 ± 5 | 36 ± 5 | .022 |
| Urea reduction ratio, mean ± SD | 73 ± 7 | 76 ± 6 | < .001 |
| Thrombophilia, no. (%) | |||
| Factor V Leiden | 7 (6.5) | 6 (1.9) | .046 |
| Prothrombin gene mutation 20210G > A | 3 (2.8) | 9 (2.9) | > .999 |
| Anticardiolipin antibodies (IgG) at least 30 GPL U/mL | 2 (1.9) | 5 (1.6) | > .999 |
| Anticardiolipin antibodies (IgM) at least 30 MPL U/mL | 2 (1.9) | 8 (2.6) | > .999 |
| Lupus anticoagulant | 2 (1.9) | 8 (2.6) | > .999 |
| Factor VIII level greater than 90th percentile* | 18 (16.8) | 30 (9.7) | .047 |
| Homocysteine at least at 85th percentile† | 22 (20.6) | 40 (12.9) | .057 |
| Lipoprotein(a) at least at 85th percentile‡ | 23 (21.5) | 41 (13.3) | .042 |
| Presence of any thrombophilia | 59 (55.1) | 121 (39.2) | .004 |
| TGF-β1 production haplotype, no. (%) | .006 | ||
| High producers | 69 (64.5) | 232 (75.1) | |
| Intermediate producers | 28 (26.2) | 69 (22.3) | |
| Low producers | 10 (9.3) | 8 (2.6) | |
| PAI-1 genotype, no. (%) | .552 | ||
| 4G/4G | 24 (22.4) | 75 (24.3) | |
| 4G/5G | 60 (56.1) | 155 (50.2) | |
| 5G/5G | 23 (21.5) | 79 (25.6) |