Albertine Donker

Standardized Pediatric Hepcidin Values 233 7 Table 1. Demographic, clinical and laboratory characteristics of the study population (N=266) Males (n=157) Females (n=109) p Demographic and clinical characteristics Age (range) 9 (0-17) 11.5 (1-17) 0.003 Ethnicity Western-European 144 (92) 105 (96) 0.131 Mediterranean 13 (8) 4(4) 0.131 BMI a Underweight 3 (2) 6 (5) 0.111 Normal weight 131 (83) 91 (84) 0.922 Overweight 18 (12) 10 (9) 0.549 Obese 5 (3) 2 (2) 0.499 Time of blood sampling Between 7.30AM and-12 PM 76 (48) 50 (46) 0.684 Between 12 PM and 3 PM 58 (37) 44 (40) 0.572 Between 3 PM and 6 PM 23 (15) 15 (14) 0.839 Laboratory characteristics Hemoglobulin, g/dL 12.6 (10.4-15.5) 12.6 (10.5-15.1) 0.837 Ht, L/L 0.4 (0.3-0.5) 0.4 (0.3-0.5) 0.706 Reticulocytes, x10 9 /L 47.5 (26.9- 78.4) 52.0 (25.0-106.8) 0.209 MCV, fL 82.0 (72.0-90.0) 84.0 (76.8-94.8) 0.000 MCH, fmol 1.8 (1.5-1.9) 1.8 (1.6-2.0) 0.301 Ferritin, µg/L 41.0 (15.9-98.1) 40.0 (16.5-112.8) 0.937 Iron, µmol/L 16.0 (3.0-26.2) 15.5 (4.0-29.3) 0.903 TIBC, µmol/L 64.5 (50.0-83.0) 66.0 (47.0-86.5) 0.194 TSAT, % 24.0 (9.5-45.0) 23.0 (6.6-45.5) 0.978 sTfR, mg/L 1.3 (0.9-2.0) 1.2 (0.8-1.9) 0.082 ALT, IU/L 18.0 (11.0-42.3) 17.0 (9.8-31.2) 0.229 CRP b , mg/L 0.2 (0.0-3.7) 0.3 (0.0-4.4) 0.209 Data are given as median for continuous variables and as n for categorical variables. For the continuous variables values in parenthesis refer to ranges (age) or p2.5-p97.5, for the categorical variables values in parenthesis refer to percentages. p values for continuous variables were calculated with independent sample median test, p values for categorical values were calculated with Chi Square test. a BMI was assessed according to international standards established by Cole et al 36 b In a 3 year old male, CRP was missing. Hepcidin was low (0.58 nM) in this child, arguing against inflammation. Therefore this case was not excluded although CRP>5 mg/L was an exclusion criterion for the study. Abbreviations: BMI denotes Body Mass Index