Table 1.
Baseline Characteristics by Quartile of FGF23.
| Characteristic | FGF23 Quartile 1 (n=568) |
FGF23 Quartile 2 (n=570) |
FGF23 Quartile 3 (n=569) |
FGF23 Quartile 4 (n=569) |
P value (linear trend) |
|---|---|---|---|---|---|
| Age, y, mean±SD | 58.7±9.2 | 59.4±9.1 | 59.0±9.4 | 60.1±9.5 | 0.06 |
| Female, n (%) | 329 (57.9) | 300 (52.6) | 295 (51.9) | 308 (54.1) | 0.17 |
| Race, n (%) | 0.04 | ||||
| Black | 139 (24.5) | 137 (24.0) | 133 (23.4) | 119 (20.9) | |
| Chinese | 78 (13.7) | 83 (14.6) | 69 (12.1) | 70 (12.3) | |
| Hispanic | 135 (23.8) | 115 (20.2) | 117 (20.6) | 100 (17.6) | |
| White | 216 (38.0) | 235 (41.2) | 250 (43.9) | 280 (49.2) | |
| Current Smoker, n (%) | 86 (15.2) | 48 (8.4) | 55 (9.7) | 45 (7.9) | 0.001 |
| Body mass index, kg/m2, mean ± SD | 27.0±4.8 | 27.4±4.9 | 27.5±4.8 | 28.4±5.2 | <0.001 |
| Systolic blood pressure, mmHg, mean ± SD | 122.2±21.3 | 121.8±19.7 | 121.9±19.4 | 123.7±19.2 | 0.37 |
| Anti-hypertensive medication, n (%) | 129 (22.7) | 142 (24.9) | 144 (25.3) | 194 (34.1) | <0.001 |
| Diabetes mellitus, n (%) | 39 (6.9) | 53 (9.3) | 48 (8.5) | 59 (10.4) | 0.20 |
| Total cholesterol, mg/dL, mean ± SD | 194.6±35.4 | 194.4±33.2 | 195.7±36.6 | 195.3±36.1 | 0.93 |
| LDL cholesterol, mg/dL, mean ± SD | 116.8±31.9 | 118.1±31.1 | 118.7±31.6 | 117.8±31.3 | 0.78 |
| Glucose, mg/dL, median (IQR) | 87 (81–96) | 88 (82–95) | 87 (82–96) | 88 (83–96) | 0.95 |
| eGFR mL/min/1.73 m2, mean ± SD | 83.8±14.4 | 80.4±13.8 | 79.8±14.6 | 74.6±15.6 | <0.001 |
| Calcium, mg/dL, mean ± SD | 9.6±0.4 | 9.6±0.4 | 9.7±0.4 | 9.7±0.4 | 0.003 |
| 25- hydroxyvitamin D, ng/mL, mean ± SD | 24.9±12.5 | 25.7±11.2 | 26.6±11.3 | 27.6±11.2 | <0.001 |
| Phosphate, urine, mg/dL, mean ± SD | 47.3±31.8 | 48.5±31.1 | 51.2±37.1 | 54.9±41.7 | 0.002 |
| Parathyroid hormone, pg/mL, mean ±SD | 42.1±18.2 | 41.8±17.1 | 42.4±18.1 | 42.7±18.1 | 0.86 |
| Angiotensin converting enzyme inhibitor, n (%) | 50 (8.8) | 53 (9.3) | 51 (9.0) | 66 (11.6) | 0.34 |
| Angiotensin receptor blocker, n(%) | 15 (2.7) | 23 (4.1) | 18 (3.2) | 39 (6.9) | 0.002 |
FGF23 = fibroblast growth factor 23; eGFR = estimated glomerular filtration rate; LDL = low-density lipoprotein