Table 1. Baseline characteristics in cases as compared to controls.
Values are depicted as mean (95% confidence interval), frequencies, or median [interquartile range].
| Case | Control | P-value | |
|---|---|---|---|
| n = 474 | weighted n = 16,373 | ||
| Age | 64.6 (63.9, 65.3) | 64.2 (63.7, 64.6) | 0.39 |
| Black race (%) | 33 | 36 | 0.28 |
| Body mass index (kg/m2) | 29.9 (29.5, 30.5) | 29.2 (28.7, 29.7) | 0.05 |
| Male sex (%) | 42 | 43 | 0.72 |
| Region of residence (%) | <0.001 | ||
| Non-belt | 35 | 48 | |
| Buckle | 22 | 20 | |
| Belt | 44 | 32 | |
| Income < $20,000 per year (%) | 28 | 14 | <0.001 |
| Less than a high school diploma (%) | 8 | 7 | 0.63 |
| Co-morbidities | |||
| Diabetes (%) | 28 | 17 | <0.001 |
| Hypertension (%) | 61 | 55 | 0.06 |
| Coronary heart disease (%) | 20 | 14 | 0.005 |
| Current smoking (%) | 17 | 12 | 0.04 |
| Physical activity, none (%) | 38 | 32 | 0.07 |
| Chronic kidney disease (%) | 26 | 17 | <0.001 |
| Laboratory measures | |||
| Calcium (mg/dL) | 9.16 (9.10, 9.22) | 9.25 (9.20, 9.30) | 0.08 |
| Phosphorus (mg/dL) | 3.48 (3.44, 3.52) | 3.52 (3.47, 3.56) | 0.24 |
| Parathyroid hormone (pg/ml) | 47.1 (44.4, 49.8) | 43.4 (41.8, 45.0) | 0.15 |
| 25-hydroxyvitamin D (ng/ml) | 25.8 (24.8, 26.7) | 26.8 (25.9, 27.6) | 0.03 |
| Fibroblast growth factor 23 (RU/ml) | 74.3 [56.2, 112.4] | 67.9 [51.9, 97.0] | 0.03 |