Table 1. Patient characteristics and outcomes, total cohort and by hepcidin tertile.
hepcidin tertile | |||||
---|---|---|---|---|---|
total cohort | <44 ng/ml | 44–76 ng/ml | >76 ng/ml | ||
n = 249 | n = 83 | n = 84 | n = 82 | p-value | |
age, yrs | 66.5 (57.0–73.2) | 67.6 (57.2–73.2) | 66.0 (55.4–72.5) | 66.3 (58.1–74.2) | 0.9 |
gender, male | 52.6% | 42.2% | 52.4% | 63.4% | 0.02 |
body mass index, kg/m2 | 29.4 (27.0–33.2) | 29.3 (26.8–34.1) | 29.6 (27.8–32.9) | 29.4 (26.4–32.9) | 0.8 |
Diabetes mellitus | 0.5 | ||||
Type 1 | 10.0% | 12.1% | 7.1% | 11.0% | |
Type 2 | 90.0% | 88.9% | 92.9% | 89.0% | |
duration of diabetes, yrs | 10 (4–21.5) | 10 (3–19) | 12 (4–24) | 10 (4–22) | 0.5 |
diabetic retinopathy a | 32.1% | 28.9% | 33.3% | 34.2% | 0.7 |
history of CVD b | 32.1% | 37.4% | 32.1% | 26.8% | 0.4 |
smoking c | 27.4% | 24.4% | 33.3% | 24.4% | 0.3 |
hypertension a | 81.9% | 73.5% | 85.7% | 86.6% | 0.049 |
blood pressure, mmHg | |||||
systolic | 143 ± 22 | 142 ± 20 | 143 ± 23 | 144 ± 22 | 0.9 |
diastolic | 81 ± 14 | 80 ± 15 | 81 ± 14 | 80 ± 12 | 0.8 |
hyperlipidemia a | 42.2% | 32.5% | 42.9% | 51.2% | 0.052 |
Laboratory | |||||
GFR, ml/min/1.73m2 | 51 (30–71) | 53 (39–76) | 51 (31–70) | 44 (25–70) | 0.07 |
CKD d | 0.05 | ||||
stage G1 | 6.3% | 6.6% | 4.9% | 7.4% | |
stage G2 | 30.5% | 29.0% | 35.4% | 27.2% | |
stage G3a | 18.0% | 25.0% | 15.9% | 13.6% | |
stage G3b | 18.8% | 23.7% | 19.5% | 13.6% | |
stage G4 | 19.7% | 13.2% | 20.7% | 24.7% | |
stage G5 | 6.7% | 2.6% | 3.7% | 13.6% | |
proteinuria, mg/day | 186 (107–1145) | 156 (94–530) | 182 (119–879) | 300 (127–1605) | 0.10 |
HbA1c, % | 6.9 (6.4–8.0) | 6.9 (6.4–7.8) | 7.1 (6.4–8.1) | 6.9 (6.4–8.1) | 0.9 |
C-reactive protein, mg/dL | 0.34 (0.14–0.78) | 0.34 (0.16–0.63) | 0.25 (0.11–0.90) | 0.37 (0.19–0.99) | 0.4 |
albumin, g/dL | 4.1 (3.8–4.4) | 4.1 (3.8–4.4) | 4.1 (3.9–4.4) | 4.2 (3.8–4.6) | 0.8 |
total cholesterol, mg/dL | 198 (176–223) | 198 (176–221) | 194 (174–209) | 199 (177–227) | 0.6 |
hemoglobin, g/L | 131 ± 20 | 132 ± 19 | 133 ± 20 | 129 ± 19 | 0.3 |
anemia e | 37.9% | 31.1% | 33.3% | 49.4% | 0.04 |
ferritin, μg/L | 149 (71–244) | 65 (38–112) | 154 (105–223) | 260 (159–363) | <0.001 |
EPO, U/L | 13.5 (9.2–18.4) | 15.2 (9.6–23.7) | 12.8 (9.1–16.6) | 13.4 (9.3–16.7) | 0.04 |
hepcidin, ng/ml | 62.0 (33.0–83.0) | 26 (16.8–33) | 62 (55–69) | 96 (83–120) | <0.001 |
Outcomes | |||||
death | 19.7% | 22.9% | 13.1% | 23.2% | 0.18 |
initiation of RRT | 14.1% | 4.8% | 15.5% | 22.0% | 0.006 |
doubling of SCr | 2.0% | 2.6% | 2.9% | 1.6% | 0.9 |
progression of CKD (RRT or doubling of SCr) | 16.1% | 7.4% | 18.1% | 23.2% | 0.02 |
Legend: data are means ± standard deviation, medians (interquartile range) and proportions (%); p-value across hepcidin tertiles; abbreviations: EPO, endogenous erythropoietin; CVD, cardiovascular disease, GFR, glomerular filtration rate; TIA, transient ischemic attack; SCr, serum creatinine; RRT, renal replacement therapy.
a self-reported history or as specified in the patient’s chart
b self-reported history of angina pectoris, myocardial infarction, stroke /TIA, or as specified in the patient’s chart
c current smoker or stopped within the past 5 yrs
d CKD stages G1 and G2 defined as proteinuria and GFR >90 ml/min and 60–90 ml/min, respectively
e hemoglobin <120 g/L in women and <135 g/L in men