Table 2.
Baseline characteristics of the study population stratified by quartile of Na coefficient of variation (CV)
| 1st CV ≤ 0.71 n = 14,580 |
2nd 0.71 < CV ≤ 1.25 n = 14,037 |
3rd 1.25 < CV ≤ 1.94 n = 14,206 |
4th CV > 1.94 n = 14,138 |
p value | |
|---|---|---|---|---|---|
| Age, years, mean (SD) | 57.8 (18.3) | 60.5 (17.9) | 62.1 (17.3) | 63.2 (18.0) | < 0.001 |
| Men, n (%) | 6587 (45.2) | 6806 (48.5) | 6925 (48.7) | 6314 (44.7) | < 0.001 |
| Charlson/Deyo score, n (%) | < 0.001 | ||||
| 0 | 11,771 (80.7) | 10,869 (77.4) | 10,754 (75.7) | 10,563 (74.7) | |
| 1 | 2063 (14.1) | 2232 (15.9) | 2375 (16.7) | 2412 (17.1) | |
| 2 | 411 (2.8) | 531 (3.8) | 585 (4.1) | 642 (4.5) | |
| > 2 | 335 (2.3) | 405 (2.9) | 492 (3.5) | 521 (3.7) | |
| Comorbidities, n (%) | |||||
| Cardiovascular | 5130 (35.2) | 5424 (38.6) | 5837 (41.1) | 5677 (40.2) | < 0.001 |
| Malignancies | 4151 (28.5) | 4440 (31.6) | 4808 (33.8) | 4671 (33.0) | < 0.001 |
| Gastrointestinal | 2307 (15.8) | 2229 (15.9) | 2342 (16.5) | 2242 (15.9) | 0.363 |
| Genito/urinary | 1408 (9.7) | 1502 (10.7) | 1617 (11.4) | 1801 (12.7) | < 0.001 |
| Endocrine/metabolic | 2466 (16.9) | 2441 (17.4) | 2655 (18.7) | 2508 (17.7) | 0.001 |
| Infectious | 496 (3.4) | 632 (4.5) | 820 (5.8) | 1101 (7.8) | < 0.001 |
| Respiratory | 1277 (8.8) | 1654 (11.8) | 2122 (14.9) | 2572 (18.2) | < 0.001 |
| eGFR, mean (SD), mL/min/1.73 m2* | 83.0 (25.0) | 80.1 (25.5) | 78.1 (25.8) | 77.3 (27.1) | < 0.001 |
| Na, median (IQR), mEq/L* | 140.0 (139.0, 142.0) | 140.0 (138.0, 142.0) | 140.0 (138.0, 142.0) | 139.0 (136.0, 142.0) | < 0.001 |
| Na CV, median (IQR) | 0.5 (0.0, 0.5) | 1.0 (1.0, 1.1) | 1.5 (1.5, 1.7) | 2.5 (2.1, 3.1) | < 0.001 |
*Value at hospital admission