Table 2.
Patient baseline demographic and clinical characteristics
| Variable | Total (N = 252) |
|---|---|
| Age (years) | |
| Mean (SD) | 70.6 (13.37) |
| Median | 72.0 |
| Range | 26, 96 |
| Age group, n (%) | |
| 18 to < 55 years | 27 (10.7) |
| 55 to < 65 years | 57 (22.6) |
| 65 to < 75 years | 53 (21.0) |
| 75 to < 85 years | 79 (31.3) |
| ≥ 85 years | 36 (14.3) |
| Sex, n (%) | |
| Female | 127 (50.4) |
| Male | 125 (49.6) |
| Race, n (%) | |
| Caucasian | 248 (98.4) |
| Asian | 3 (1.2) |
| Unknown | 1 (0.4) |
| Baseline BMI (kg/m2) | |
| n | 216 |
| Mean (SD) | 23.87 (4.489) |
| Median | 23.50 |
| Range | 14.0, 43.6 |
| SIADH etiology, n (%)a | |
| Tumor | 107 (42.5) |
| Idiopathic | 66 (26.2) |
| Drug | 22 (8.7) |
| Pulmonary | 14 (5.6) |
| Disorders of the central nervous system (bleeding and masses) | 5 (2.0) |
| Disorders of the central nervous system (bleeding and masses, head trauma) | 5 (2.0) |
| Serum sodium (mmol/l) | |
| n | 219 |
| Mean (SD) | 123.2 (6.59) |
| Median | 124.0 |
| Range | 103, 142b |
| Volume status, n (%) | |
| Normovolemic | 227 (90.1) |
| Hypervolemic | 10 (4.0) |
| Hypovolemicc | 9 (3.6) |
| Missing | 6 (2.4) |
For each baseline variable, only patients with available data are shown
BMI body mass index, SD standard deviation, SIADH syndrome of inappropriate secretion of antidiuretic hormone
aEtiologies present in ≥ 2% of patients are listed
bOne patient had serum sodium 142 mmol/l at baseline (time of consent to study enrollment), but tolvaptan treatment was not initiated until 5 days later, when the patient had serum sodium 127 mmol/l
cNine patients were hypovolemic at the time of hyponatremia diagnosis, but only one was hypovolemic when tolvaptan was initiated, and the status of another of the nine patients was not known