| Hyponatraemia (Na<135 mEq/L) n=29 (18.86%) | Normonatraemia (Na=135–145 mEq/L) n=143 (83.14%) | P-value | |
|---|---|---|---|
| Age | 90.1 (86.4–93.4) | 88.4 (85.5–90.3) | 0.1287* |
| Nonagenarians | 15 (52.72%) | 40 (27.97%) | 0.0164¥ |
| Females | 20 (68.97%) | 83 (58.04%) | 0.3056¥ |
| Barthel | 50 (20–70) | 65 (45–85) | 0.0103* |
| Pfeiffer | 4 (2–6) | 3 (1–5) | 0.1777* |
| Polypharmacy | 10.0 (8–14) | 11.0 (8–14) | 0.9706* |
| Loop diuretics | 17 (58.62%) | 92 (64.34%) | 0.6729¥ |
| Thiazides | 10 (34.48%) | 12 (8.39%) | 0.0006¥ |
| Potassium-sparing | 3 (10.34%) | 6 (4.20%) | 0.1781¥ |
| Selective serotonin reuptake inhibitors | 7 (24.14%) | 28 (19.58%) | 0.6147¥ |
| Antipsychotics | 5 (17.24%) | 32 (22.38%) | 0.6280¥ |
| Na+(mEq/L) | 132 (131–133) | 139 (138–141) | 0.0000* |
| K+ (mEq/L) | 4.8 (4.25–5.05) | 4.5 (4.1–4.8) | 0.0667* |
| Glomerular filtration rate (GFR) (ml/min) | 27.7 (19.6–52.9) | 43.7 (28.9–61.7) | 0.0213* |
| Heart failure | 12 (41.38%) | 79 (55.24%) | 0.2213¥ |
| Atrial fibrillation | 11 (37.93%) | 59 (41.26%) | 0.8370¥ |
| Diabetes mellitus | 19 (65.52%) | 59 (41.26%) | 0.0236¥ |
| Renal failure (GFR<30 ml/min) | 15 (51.72%) | 34 (23.94%) | 0.0057¥ |
| LOS (days) | 13 (9–17) | 10 (7–16) | 0.1318* |
| Mortality | 4 (13.79%) | 19 (13.29%) | 1.0000¥ |
| 30 day re-admission | 7 (28.00%) | 28 (22.58%) | 0.6070¥ |
| 30 day mortality | 2 (8.00%) | 7 (5.65%) | 0.6470¥ |
* -Mann–Whitney U -and Wilcoxon. Median data (P25–P75).¥Fisher’s exact test