Table 1.
Baseline characteristics of the cohort according to tertiles of pre-dialysis calculated osmolarity
| Total (N=3,142) | Calculated Osmolarity Tertile | Pa | |||
|---|---|---|---|---|---|
| 1 (n=1,048) | 2 (n=1,049) | 3 (n=1,045) | |||
| Age (y) | 62.6 ± 15.2 | 64.0 ± 14.9 | 62.5 ± 14.9 | 61.4 ± 15.5 | <0.001 |
| Male sex | 1795, 57.1 | 555, 53.0 | 596, 56.8 | 644, 61.6 | <0.001 |
| Black race | 406, 12.9 | 145, 13.8 | 141, 13.4 | 120, 11.5 | 0.2 |
| Diabetes | 1918, 61.0 | 624, 59.5 | 643, 61.3 | 651, 62.3 | 0.4 |
| IHD | 529, 16.8 | 181, 17.3 | 174, 16.6 | 174, 16.6 | 0.9 |
| CHF | 772, 24.6 | 252, 24.0 | 274, 26.1 | 246, 23.5 | 0.4 |
| Access type | 0.2 | ||||
| AVF | 1965, 62.6 | 639, 61.0 | 659, 62.8 | 667, 63.8 | |
| AVG | 570, 18.1 | 200, 19.1 | 202, 19.3 | 168, 16.1 | |
| Catheter | 607, 19.3 | 209, 19.9 | 188, 17.9 | 210, 20.1 | |
| Session Length | 0.4 | ||||
| ≤180 min | 1818, 57.9 | 585, 55.8 | 611, 58.3 | 622, 59.5 | |
| 181–209 min | 781, 24.9 | 270, 25.8 | 252, 24.0 | 259, 24.8 | |
| >209 min | 543, 17.2 | 193, 18.4 | 186, 17.7 | 164, 15.7 | |
| Postdialysis weight (kg) | 76.2 ± 20.9 | 76.4 ± 21.4 | 76.3 ± 20.3 | 76.0 ± 20.9 | 0.9 |
| Serum Sodium (mmol/L) | 136.8 ± 3.2 | 134.9 ± 3.1 | 137.1 ± 2.6 | 138.4 ± 2.9 | <0.001 |
| Serum Albumin (g/dL) | 3.8 ± 0.4 | 3.7 ± 0.4 | 3.9 ± 0.4 | 3.9 ± 0.4 | <0.001 |
| SUN (mg/dL) | 65.9 ± 19.8 | 51.6 ± 14.6 | 64.1 ± 14.0 | 82.0 ± 17.4 | <0.001 |
| Serum Bicarbonate (mmol/L) | 24.0 ± 3.3 | 24.3 ± 3.4 | 23.9 ± 3.3 | 23.7 ± 3.4 | <0.001 |
| Serum Glucose (mg/dL) | 142.3 ± 70.2 | 128.4 ± 57.3 | 145.3 ± 71.8 | 153.3 ± 77.7 | <0.001 |
| Calculated osmolarity (mOsm/L) | 305.1 ± 9.5 | 295.0 ± 5.7 | 305.2 ± 2.2 | 315.2 ± 5.3 | <0.001 |
Note: Values for categorical variables are given as number (percentages); values for continuous variables, as mean ± standard deviation. Conversion factors for units: glucose in mg/dL to mmol/L, ×0.05551; SUN in mg/dL to mmol/L, ×0.357.
IHD, ischemic heart disease; CHF, congestive heart failure; AVF, arteriovenous fistula; AVG, arteriovenous graft; SUN, serum urea nitrogen.
a
P values refer to testing the null of no difference between groups, using analysis of variance for continuous variables and χ2 tests for categorical variables.