Table 1.
Clinical characteristics and biochemistry of patients as a whole and of patients subdivided according to quartiles of parathyroid hormone
| All patients | 1st quartile PTH (≤50 pg/ml) | 2nd quartile PTH (51–69 pg/ml) | 3rd quartile PTH (70–132 pg/ml) | 4th quartile PTH (≥133 pg/ml) | P across quartiles | |
|---|---|---|---|---|---|---|
| No. patients | 979 | 245 | 245 | 244 | 245 | |
| Age (years) | 56.8 (48.0–66.0) | 54.0 (44.0–64.0) | 53.0 (48.0–60.0) | 62.0 (50.0–70.0) | 59.0 (50.0–73.0) | 0.000 |
| Male (%) | 658 (67) | 175 (71.8) | 153 (62.9) | 165 (66.8) | 165 (67.3) | 0.166 |
| Diabetes (%) | 243 (24.8) | 51 (21) | 59 (24) | 71 (29) | 61 (25) | 0.330 |
| Body mass index (kg/m2) | 26.7 (24.1–30.0) | 26.7 (24.0–30.0) | 26.9 (24.2–32.0) | 26.1 (23.8–29.9) | 25.9 (24.0–29.2) | 0.547 |
| Glomerular filtration rate (ml/min) | 36.0 (28.0–67.0) | 74.0 (49.5–110.0) | 30.5 (28.4–60.9) | 33.8 (28.4–49.0) | 29.0 (20.0–36.0) | 0.000 |
| Hemoglobin (g/dl) | 12.5 (11.0–14.0) | 14.0 (12.8–15.3) | 12.5 (11.0–13.7) | 12.5 (11.0–13.6) | 11.3 (10.5–12.2) | 0.000 |
| Iron (µg/dl) | 76.0 (57.0–97.0) | 82.0 (61.0–103.0) | 82.5 (64.0–103.5) | 66.0 (54.0–92.0) | 68.0 (46.5–92.5) | 0.000 |
| Ferritin (ng/ml) | 105.0 (54.0–187.0) | 107.0 (50.5–200.5) | 104.5 (49.3–175.3) | 100.0 (52.0–169.0) | 100.0 (60.0–168.0) | 0.198 |
| Transferrin (mg/dl) | 302 (266–343) | 312 (272–356) | 298 (266–334) | 300 (264–340) | 295 (253–331) | 0.045 |
| Transferrin saturation (%) | 18 (14–23) | 19 (14–23) | 21 (16–25) | 17 (13–20) | 19 (13–24) | 0.019 |
| Calcium (mg/dl) | 9.4 (9.0–9.8) | 9.6 (9.2–9.8) | 9.6 (9.3–10.0) | 9.4 (9.0–9.9) | 9.0 (8.5–9.4) | 0.000 |
| Phosphorus (mg/dl) | 4.0 (3.3–4.8) | 3.6 (3.1–4.1) | 4.6 (3.5–5.0) | 3.8 (3.2–4.7) | 4.4 (3.8–5.3) | 0.000 |
| Alkaline phosphatase (IU/l) | 77 (60–98) | 70 (57–91) | 73 (59–90) | 84 (66–106) | 93 (69–122) | 0.000 |
| Proteinuria (mg/24 h) | 621 (210–1550) | 525 (205–1,330) | 330 (174–1,440) | 675 (217–1,380) | 1152 (357–2,407) | 0.000 |
| C-reactive protein (mg/dl) | 6.0 (2.0–9.0) | 1.1 (1.1–5.7) | 8.0 (5.0–10.0) | 7.0 (2.0–10.0) | 4.5 (2.0–7.0) | 0.007 |
| Uric acid (mg/dl) | 6.1 (5.1–7.2) | 5.7 (4.8–6.8) | 5.8 (4.7–6.7) | 6.6 (5.6–7.5) | 6.8 (5.8–7.9) | 0.000 |
| Fibrinogen (mg/dl) | 364.0 (300.0–455.0) | 330.0 (276.0–431.0) | 353.0 (293.0–426.0) | 372.0 (308.0–450.0) | 399.0 (343.0–498.0) | 0.000 |
| Serum albumin (mg/dl) | 4.2 (3.8–4.6) | 4.4 (4.2–4.7) | 4.4 (4.1–4.6) | 4.2 (3.8–4.6) | 3.9 (3.5–4.3) | 0.000 |
| Homocysteine (µg/l) | 18.3 (14.0–23.8) | 16.0 (12.0–21.3) | 17.2 (14.3–21.1) | 21.5 (16.5–27.0) | 26.5 (20.0–35.2) | 0.000 |
| Total cholesterol (mg/dl) | 179 (151–210) | 190 (162–226) | 187 (158–212) | 175 (147–200) | 166 (139–191) | 0.000 |
| Triglycerides (mg/dl) | 122 (93–176) | 122 (92–172) | 109 (81–146) | 125 (96–174) | 128 (99–190) | 0.048 |
| HDL-cholesterol (mg/dl) | 48 (38–58) | 48 (38–59) | 50 (39–63) | 48 (40–56) | 47 (35–56) | 0.225 |
| LDL-cholesterol (mg/dl) | 103 (82–129) | 113 (91–142) | 107 (84.8–131) | 100 (77–118) | 98 (82–115) | 0.000 |
| Hemoglobin <12.0 mg/dl (%) | 399 (40.8) | 33 (13.5) | 105 (42.8) | 99 (40.5) | 161 (65.5) | 0.000 |
| Hemoglobin <11.0 mg/dl (%) | 225 (23) | 13 (5.3) | 62 (25.4) | 55 (22.5) | 91 (37.1) | 0.000 |
| Hemoglobin <10.0 mg/dl (%) | 103 (10.5) | 8 (3.5) | 3 (1.5) | 31 (12.5) | 60 (24.5) | 0.000 |