Table 1:
Baseline characteristics of 25 910 adult patients for whom hemodialysis was initiated between 2001 and 2007 in Canada
| Characteristic | Stage of initiation; no. (%) of patients* | p value | |
|---|---|---|---|
| Early†n = 8441 | Late‡n = 17 469 | ||
| Age, yr, mean (SD) | 67.5 (14.0) | 63.7 (15.2) | < 0.001 |
| Sex, male | 5656 (67.0) | 9 853 (56.4) | < 0.001 |
| Ethnicity | < 0.001 | ||
| Asian | 329 (3.9) | 1 013 (5.8) | |
| Black | 253 (3.0) | 542 (3.1) | |
| White | 6576 (77.9) | 12 979 (74.3) | |
| Other | 726 (8.6) | 2 079 (11.9) | |
| Unknown | 557 (6.6) | 856 (4.9) | |
| Estimated GFR, mL/min per 1.73 m2 | |||
| Mean (SD) | 15.5 (7.7) | 7.1 (2.0) | < 0.001 |
| Median (IQR) | 13.4 (3.8) | 7.2 (3.0) | < 0.001 |
| Serum albumin before dialysis, g/L | |||
| Mean (SD) | 32.0 (7.0) | 31.9 (6.8) | 0.29 |
| Median (IQR) | 33.0 (9.0) | 32.0 (9.0) | 0.033 |
| Primary cause of renal disease | 0.018 | ||
| Glomerulonephritis | 608 (7.2) | 2 247 (12.9) | |
| Diabetes mellitus | 3427 (40.6) | 5 917 (33.9) | |
| Renal vascular disease | 1865 (22.1) | 3 364 (19.3) | |
| Other | 1427 (16.9) | 3 765 (21.6) | |
| Cause uncertain or unknown | 1114 (13.2) | 2 176 (12.5) | |
| Late referral | 2807 (35.9) | 6 585 (40.6) | < 0.001 |
| Dialysis access via arteriovenous fistula or arteriorvenous graft | 1774 (22.3) | 3 799 (22.7) | 0.46 |
| Comorbidity index for end- stage renal disease, mean (SD) | 2.6 (2.3) | 1.9 (2.1) | < 0.001 |
| Comorbidities | |||
| Coronary artery disease | 3790 (44.9) | 5 468 (31.3) | < 0.001 |
| Peripheral vascular disease | 2195 (26.0) | 3 144 (18.0) | < 0.001 |
| Cerebrovascular disease | 1418 (16.8) | 2 306 (13.2) | < 0.001 |
| Diabetes mellitus | 4448 (52.7) | 7 577 (43.4) | < 0.001 |
| Hypertension | 6930 (82.1) | 14 377 (82.3) | 0.65 |
| Pulmonary edema | 2760 (32.7) | 4 193 (24.0) | < 0.001 |
| Lung disease | 1418 (16.8) | 2 184 (12.5) | < 0.001 |
| Other malignancy or serious disease | 2026 (24.0) | 3 529 (20.2) | < 0.001 |
| Transplant§ | 490 (5.8) | 2 166 (12.4) | < 0.001 |
Note: GFR = glomerular filtation rate, IQR = interquartile range, SD = standard deviation.
*
Unless stated otherwise.
†
Early initiation was defined as initiation with estimated GFR > 10.5 mL/min per 1.73 m2.
‡
Late initiation was defined as initiation with estimated GFR ≤ 10.5 mL/min per 1.73 m2.
§
Transplantation was performed during follow-up, after initiation of dialysis.