Hepcidin is the systemic regulator of iron homeostasis and may serve as a marker of iron status; however it has not been assessed in prospective iron fortification interventions. Iron biomarker kinetics may allow visualization of time effects and population dynamics during iron repletion.The objective ofthis study was to assess the time-dependent rise in iron status markers and hepcidin following iron fortification.
449 Moroccan children aged 3-14 y were randomised to consume fortified (8 mg iron) or control biscuits for 28 weeks (6 days/week). At baseline, at two randomised midpoints (between weeks 5-11 and weeks 13-21), and at endpoint, we measured hepcidin, serum ferritin (Sf), body iron stores (BIS), and haemoglobin (Hb). We evaluated the effect of the time-by-treatment interaction on the outcomes by repeated measured mixed effect models. Model fit was evaluated by Akaike (AIC) and Bayesian (BIC) Information Criteria.
Preliminary analysis (n=304) revealed a baseline median (IQR) hepcidin of 2.7 µg/L (1.4-4.4), Sf of 22.8 µg/L (13.7-32.0), BIS of 4.0 mg/Kg BW (1.9-5.6), and Hb of 12.2 g/dL (11.5-12.8). While iron fortification significantly improved Sf and BIS compared to control (time-by-treatment effect: p<0.001) no effect was observed for hepcidin (p=0.16). However, hepcidin was a significant covariate to the models for Sf and BIS; their fit improved with significantly lower AIC and BIC (p<0.001).
Our preliminary results suggest that hepcidin is a less sensitive biomarker in measuring the effect of iron interventions than SF and BIS but may improve the explanatory power of predictive models for iron status.