Table 1.
Baseline data of the study cohort, stratified by dialysis vintage.
| Variable | All patients | Vintage < 2 yrs* | Vintage ≥ 2 yrs* | |||
|---|---|---|---|---|---|---|
| PD (n=12,171) |
HD (n=117,851) |
PD (n=9,730) |
HD (n=86,837) |
PD (n=2,441) |
HD (n=31,014) |
|
| Age (years) | 54 ± 16 | 62 ± 16 | 55 ± 17 | 63 ± 16 | 52 ± 15 | 59 ± 15 |
| Age >65 years | 29 | 46 | 31 | 49 | 22 | 40 |
| Women | 47 | 45 | 46 | 45 | 51 | 46 |
| Diabetes mellitus | 38 | 45 | 41 | 47 | 26 | 38 |
| Race and/or ethnicity | ||||||
| Caucasians | 54 | 43 | 56 | 46 | 43 | 34 |
| Blacks | 23 | 32 | 20 | 29 | 31 | 41 |
| Hispanics | 13 | 15 | 13 | 15 | 14 | 14 |
| Others | 10 | 10 | 10 | 9 | 12 | 11 |
| Dialysis Vintage (mo) | 3 (1, 17) | 3 (1, 26) | 2 (1, 3) | 2 (1, 4) | 46 (33, 72) | 50 (35, 78) |
| Primary insurance | ||||||
| Medicare | 58 | 68 | 53 | 63 | 81 | 81 |
| Medicaid | 4 | 6 | 4 | 7 | 4 | 6 |
| Others | 38 | 26 | 43 | 30 | 15 | 13 |
| Co-morbidities | ||||||
| IHD | 15 | 19 | 16 | 21 | 10 | 16 |
| CHF | 18 | 27 | 19 | 29 | 14 | 23 |
| MI | 6 | 7 | 6 | 7 | 4 | 5 |
| Cardiac arrest | 0.5 | 0.6 | 0.5 | 0.6 | 0.3 | 0.5 |
| Pericarditis | 0.6 | 0.6 | 0.5 | 0.6 | 0.9 | 0.9 |
| Cardiac dysrhythmia | 3 | 4 | 3 | 5 | 3 | 3 |
| CBVD | 5 | 7 | 5 | 8 | 4 | 6 |
| PVD | 8 | 11 | 9 | 12 | 6 | 9 |
| COPD | 4 | 6 | 4 | 6 | 2 | 4 |
| Current Smokers | 5 | 5 | 5 | 5 | 6 | 5 |
| Weight (kg) | 76 ± 20 | 75 ± 21 | 76 ± 20 | 75 ± 21 | 78 ± 22 | 74 ± 21 |
| BMI (kg/m2) | 27 ± 8 | 27 ± 7 | 27 ± 8 | 27 ± 7 | 27 ± 6 | 26 ± 7 |
| Serum albumin (g/dL) | 3.6 ± 0.5 | 3.7 ± 0.5 | 3.6 ± 0.5 | 3.6 ± 0.5 | 3.6 ± 0.5 | 3.8 ± 0.4 |
| Creatinine (mg/dL) | 8.4 ± 3.8 | 8.0 ± 3.3 | 7.8 ± 3.5 | 7.2 ± 3.1 | 11.2 ± 4.0 | 10.0 ± 3.2 |
| Ferritin (ng/mL) | 245 (112, 498) | 388 (183, 720) | 223 (103, 441) | 314 (155, 595) | 394 (168, 748) | 656 (382, 973) |
| TIBC (mg/dL) | 237 ± 51 | 208 ± 47 | 240 ± 50 | 212 ± 48 | 225 ± 51 | 194 ± 41 |
| Calcium (mg/dL) | 9.2 ± 0.8 | 9.2 ± 0.7 | 9.2 ± 0.7 | 9.1 ± 0.7 | 9.3 ± 0.9 | 9.3 ± 0.8 |
| Phosphorus (mg/dL) | 5.4 ± 1.4 | 5.6 ± 1.5 | 5.3 ± 1.4 | 5.5 ± 1.5 | 5.6 ± 1.6 | 5.8 ± 1.6 |
| PTH (pg/ml) | 283 (157, 514) | 247 (144, 422) | 271 (154, 475) | 235 (138, 385) | 345 (170, 691) | 291 (162, 556) |
| Alkaline Phosphatase (U/L) | 115 ± 85 | 121 ± 93 | 113 ± 80 | 117 ± 90 | 125 ± 100 | 130 ± 101 |
| Hemoglobin (g/dL) | 12.1 ± 1.5 | 12.0 ± 1.4 | 12.2 ± 1.5 | 12.0 ± 1.4 | 11.7 ± 1.6 | 11.8 ± 1.3 |
| WBC count (x103/µl) | 7.6 ± 2.6 | 7.5 ± 2.6 | 7.6 ± 2.5 | 7.7 ± 2.7 | 7.6 ± 3.0 | 7.0 ± 2.4 |
| % lymphocyte | 20 ± 8 | 20 ± 8 | 20 ± 8 | 20 ± 8 | 20 ± 8 | 21 ± 8 |
Categorical variables are given as percentage; continuous variables as mean +/− SD or median (25th, 75th percentile).
Data on dialysis vintage missing on 13,238 HD patients and 507 PD patients
COPD, chronic obstructive pulmonary disease; CHF, Congestive heart failure; IHD, ischemic heart disease; MI, myocardial infarction; PVD, peripheral vascular disease; BMI, body mass index; PTH, parathyroid hormone; CBVD, cerebrovascular disease; PD, peritoneal dialysis; HD, hemodialysis; TIBC, total iron-binding capacity; WBC, white blood cells
Conversion factors for units: albumin and hemoglobin in g/dL to g/L, x10; creatinine in mg/dL to umol/L, x88.4; calcium in mg/dL to mmol/L, x0.2495; phosphorus in mg/dL to mmol/L, x0.3229.
No conversion necessary for ferritin in ng/mL and ug/L, PTH in pg/mL and ng/L, and WBC count in 10^3/uL and 10^9/L.