Table 2. Characteristics of Patients With Kidney Stones and Hypercalcemia Who Completed Parathyroid Hormone Level Measurement.
| Characteristic | No. (%) | P value | ||
|---|---|---|---|---|
| Total patients (n = 1873) | Hypercalcemia | |||
| Measured (n = 1369) | Albumin-corrected (n = 504) | |||
| PTH level, median (IQR), pg/mL | 67.7 (32.0-121.6) | 71.8 (32.3-125.3) | 58.7 (31.1-104.2) | .09 |
| Serum calcium concentration, median (IQR), mg/dL | 10.8 (10.6-11.1) | 10.9 (10.7-11.2) | 10.7 (10.6-10.8) | <.001 |
| No. of calcium concentration measurements >10.5 mg/dL per patient, median (IQR) | 2.0 (1.0-4.0) | 2.0 (1.0-1.4) | 1.0 (1.0-3.0) | .58 |
| Elevated PTH level | 717 (38.3) | 558 (40.8) | 159 (31.5) | <.001 |
| 24-h Urine calcium excretion, median (IQR), mg | 206.0 (96.0-331.1) | 221.0 (111.0-324.5) | 104.5 (42.5-208.2) | <.001 |
| eGFR <45 mL/min/1.73 m2 | 804 (42.9) | 493 (36.0) | 311 (61.7) | <.001 |
| Parathyroidectomy | ||||
| Within 2 y | 189 (10.1) | 185 (13.5) | 4 (0.8) | <.001 |
| 2-5 y | 34 (1.8) | 31 (2.3) | 3 (0.6) | .02 |
Abbreviations: eGFR, estimated glomerular filtration rate; IQR, interquartile range; PTH, parathyroid hormone.
SI conversion factors: To convert serum calcium concentration to millimoles per liter, multiply by 0.25; PTH to nanograms per liter, multiply by 1.