Albertine Donker

Chapter 7 264 Supplemental Table 4. Univariable linear regression for hepcidin/ferritin ratio (pmol/µg) Males 95% CI Variable Beta a Lower limit Upper limit R 2 , % p Hb, g/dL -0.143 -0.203 -0.083 12.0 0.000 Reticulocytes, x10^9/L -0.004 -0.009 0.002 0.3 0.219 MCV, fL -0.041 -0.060 -0.023 10.3 0.000 Iron, µmol/L -0.007 -0.021 0.007 0.7 0.340 TIBC, µmol/L -0.004 -0.014 0.006 0.2 0.398 TSAT, % -0.002 -0.011 0.007 4.8 0.620 sTfR, µg/mL 0.159 -0.162 0.480 0.0 0.328 ALT, IU/L b 0.273 -0.289 0.834 0.6 0.339 CRP, mg/L b 0.135 0.008 0.262 2.1 0.038 Age, years -0.049 -0.065 -0.033 19.5 0.000 Age group, years 0-< 2 ref ref ref 2-<6 -0.034 -0.340 0.282 22.2 0.834 6-<12 -0.166 -0.454 0.121 0.254 12-<18 -0.643 -0.941 -0.345 0.000 Age, years <12 12-< 18 -0.527 -0.683 -0.371 21.9 0.000 BMI c Normal weight ref ref ref Underweight 0.725 0.145 1.305 2.4 0.015 Overweight 0.120 -0.130 0.369 0.346 Adipose 0.060 -0.393 0.513 0.794 Time blood sampling 8-12 PM ref ref ref 12-3 PM 0.109 -0.065 0.284 1.7 0.217 3- 6 PM 0.251 0.013 0.488 0.039 a Beta expresses the change in the dependent variable-log transformed hepcidin/ferritin ratio- that is associated with a 1-unit change in the independent variable. Independent variables marked with b were log-transformed as well; the interpretation of the regression coefficients for these variables is as follows: a 1% change in the independent variable corresponds to a beta % change in the ferritin/ hepcidin ratio. c BMI was assessed according to international standards established by Cole et al 1 1 Abbreviations: ref denotes reference category