Table 1. Demographics and clinical characteristics by quartiles of FGF-23.
| Variable | Full cohort | Quartile 1 | Quartile 2 | Quartile 3 | Quartile 4 |
|---|---|---|---|---|---|
| Range | 1.41–36.68 | 36.69–46.65 | 46.66–60.16 | 60.17–1615.79 | |
| N | 2738 | 683 | 685 | 686 | 684 |
| Age (years) | 74 (3) | 73 (3) | 74 (3) | 74 (3) | 74 (3) |
| Female | 1403 (51%) | 381 (56%) | 357 (52%) | 322 (47%) | 343 (50%) |
| Black | 1073 (39%) | 295 (43%) | 253 (37%) | 253 (37%) | 272 (40%) |
| Education | |||||
| < HS | 643 (24%) | 173 (25%) | 151 (22%) | 156 (23%) | 163 (24%) |
| HS grad | 884 (32%) | 226 (33%) | 230 (34%) | 217 (32%) | 211 (31%) |
| postsecondary | 1204 (44%) | 283 (42%) | 301 (44%) | 313 (46%) | 307 (45%) |
| Diabetes | 979 (36%) | 211 (31%) | 239 (35%) | 253 (37%) | 276 (40%) |
| Hypertension | 2017 (74%) | 472 (69%) | 476 (70%) | 521 (76%) | 548 (80%) |
| HTN meds use | 1489 (55%) | 297 (44%) | 343 (50%) | 389 (57%) | 460 (68%) |
| Coronary Artery Disease | 492 (18%) | 93 (14%) | 108 (16%) | 131 (19%) | 160 (24%) |
| Heart Failure | 32 (1.2%) | 3 (0.4%) | 3 (0.4%) | 3 (0.4%) | 23 (3.5%) |
| Cerebrovascular Disease | 190 (7%) | 52 (8%) | 36 (5%) | 47 (7%) | 55 (8%) |
| Systolic Blood Pressure (mmHg) | 135 (21) | 134 (20) | 135 (20) | 136 (21) | 138 (22) |
| Diastolic Blood Pressure (mmHg) | 71 (12) | 70 (12) | 72 (11) | 71 (12) | 72 (12) |
| Body Mass Index (kg/m2) | 27.3 (4.7) | 26.7 (4.7) | 27.0 (4.7) | 27.4 (4.5) | 28.1 (4.9) |
| Total Cholesterol (mg/dL) | 203 (39) | 202 (38) | 204 (39) | 201 (37) | 203 (41) |
| LDL (mg/dL) | 122 (35) | 120 (35) | 123 (34) | 121 (34) | 123 (36) |
| HDL (mg/dL) | 54 (17) | 57 (18) | 55 (18) | 52 (16) | 51 (15) |
| Statin use | 349 (13%) | 73 (11%) | 78 (11%) | 107 (16%) | 91 (13%) |
| C-reactive protein (mg/L) | 1.65 [0.99, 3.07] | 1.61 [0.96, 3.01] | 1.48 [0.92, 2.75] | 1.63 [1.00, 3.10] | 1.98 [1.09, 3.48] |
| eGFR_cysC (ml/min/1.73m2) | 72 (18) | 77 (17) | 77 (17) | 72 (17) | 64 (20) |
| eGFR_cysC < 60 | 670 (25%) | 104 (15%) | 120 (18%) | 168 (25%) | 278 (41%) |
| Urine Albumin/Creatinine ratio (mg/g) | 7.59 [3.92, 18.97] | 7.18 [3.66, 15.76] | 7.02 [3.81, 16.16] | 7.27 [3.37, 17.12] | 9.56 [4.78, 31.30] |
| UACR ≥ 30 | 471 (18%) | 89 (13%) | 96 (14%) | 115 (17%) | 171 (26%) |
| Calcium (mg/dL) | 8.87 (0.43) | 8.80 (0.39) | 8.84 (0.41) | 8.89 (0.44) | 8.95 (0.47) |
| Phosphorus (mg/dL) | 3.55 (0.48) | 3.51 (0.44) | 3.52 (0.47) | 3.53 (0.48) | 3.64 (0.51) |
| Parathyroid hormone (pg/ml) | 33.6 [22.1, 45.7] | 31.7 [23.5, 41.7] | 31.2 [24.1, 41.4] | 34.1 [25.7, 45.3] | 38.1 [27.7, 55.9] |
| 25(OH) vitD (ng/ml) | 26 (11) | 24 (12) | 26 (10) | 27 (11) | 27 (12) |
| Soluble klotho (pg/mL) | 683.1 (325.7) | 710.0 (352.2) | 700.8 (354.4) | 679.6 (307.1) | 642.0 (279.3) |