Mirjam Vreugdenhil

Zinc deficiency (ZnD) has adverse health consequences such as stunted growth. Since young children have an increased risk of developing ZnD, it is important to determine its prevalence and associated factors in this population. However, only a few studies have reported on ZnD prevalence in young children from Western high-income countries. This study evaluated ZnD prevalence and associated factors, including dietary Zn intake, in healthy 1–3-year-old children from Western European, high-income countries. ZnD was defined as serum Zn concentration <9.9 µmol/L. A total of 278 children were included with a median age of 1.7 years (Q1–Q3: 1.2–2.3). The median Zn concentration was 11.0 µmol/L (Q1–Q3: 9.0–12.2), and ZnD prevalence was 31.3%. No significant differences were observed in the socio-economic characteristics between children with and without ZnD. Dietary Zn intake was not associated with ZnD. ZnD is common in healthy 1–3-year-old children from Western European countries. However, the use of currently available cut-off values defining ZnD in young children has its limitations since these are largely based on reference values in older children. Moreover, these values were not evaluated in relation to health consequences, warranting further research.

Chronic low-grade inflammation in type 1 diabetes (T1D) might increase hepcidin synthesis, possibly resulting in functional iron deficiency (FID). We hypothesized that in T1D children with FID, hepcidin concentrations are increased compared to those with normal iron status and those with absolute iron deficiency (AID). We evaluated hepcidin concentrations in T1D children in relation to iron status, and investigated whether hepcidin is useful in assessing FID. A cross-sectional study was conducted. FID was defined as elevated zinc protoporphyrin/heme ratio and/or red blood cell distribution width, and AID as low serum ferritin concentration. Post-hoc analyses with different definitions of FID were performed, using transferrin saturation and reticulocyte hemoglobin content. Serum hepcidin concentrations were measured using mass-spectrometry. The IRODIAB-study is registered at www.trialregister.nl (NTR4642). This study included 215 T1D children with a median age of 13.7 years (Q₁–Q₃: 10.1–16.3). The median (Q₁–Q₃) hepcidin concentration in patients with normal iron status was 1.8 nmol/l (0.9–3.3), in AID-patients, 0.4 nmol/l (0.4–0.4) and in FID-patients, 1.6 nmol/l (0.7–3.5). Hepcidin concentrations in FID-patients were significantly higher than in AID-patients (p < 0.001). Irrespective of FID-definition used, hepcidin concentrations did not differ between FID-patients and patients with normal iron status. This might be explained by the influence of various factors on hepcidin concentrations, and/or by differences in response of iron parameters over time. Single hepcidin measurements do not seem useful in assessing FID in T1D children. Multiple hepcidin measurements over time in future studies, however, might prove to be more useful in assessing FID in children with T1D.

HEPCIDIN IS NOT AN APPROPRIATE INDICATOR OF IRON STATUS IN PAEDIATRIC TYPE 1 DIABETES PATIENTS Authors: Mirjam Vreugdenhil1*, Marjolijn D. Akkermans1*, E.C.A. Mieke Houdijk1, Boudewijn Bakker2, Agnes Clement-de Boers1, Daniëlle C.M. van der Kaay1, Dorine W. Swinkels3, Coby M. Laarakkers3, Martine C. de Vries4, M. Claire Woltering2, Dick Mul5, Johannes B. van Goudoever6,7, Frank