Non-anemic iron deficiency and health outcomes in pre-school children.

摘要

There is a gap in evidence on the epidemiology, diagnosis and management of non-anemic iron deficiency (NAID) in young children. Using the data from a community practice-based research network (TARGet Kids!) four studies were conducted to enrich the evidence-base related to NAID in Canadian pre-school children.;The prevalence of NAID was found to be 7% (95% CI, 5.95%-8.05%). Risk factors significantly associated with NAID included younger age (OR 1.08; 95% CI: 1.06, 1.11), higher zBMI (OR 1.22; 95% CI: 1.01, 1.48), longer duration of breastfeeding (OR 1.05; 95% CI: 1.01, 1.08) and volume of cow's milk intake (OR 1.13; 95% CI: 1.01, 1.26). Practice patterns associated with the management of NAID by community physicians showed substantial variation. Follow-up laboratory tests showed 65.5% had resolution, 25.9% had persistence and 3.4% had progression of NAID to IDA.;To identify clinically important thresholds for serum ferritin (SF) in diagnosing iron deficiency in children a restricted cubic spline regression analysis was performed. A spline curve showing the association between hemoglobin and SF identified: a threshold for SF (17.9 mug/L) where the clinical impact of iron deficiency may not come into effect until values lower than this cut-off has been reached; and a SF cut-off (4.6 mug/L) that may have clinical impact on the neurodevelopment of children.;To assess the effectiveness of iron interventions in children with NAID, the protocol for a multi-site, pragmatic, placebo controlled, superiority randomized trial was described (OptEC trial). The protocol included the methods of an internal pilot study, performed to recalculate the sample size and assess the adherence rate in children enrolled in the OptEC trial. Using internal pilot study data, the initial sample size (Na =112-198) was recalculated to range between 32-56 subjects. Adherence rate ranged between 14% -100% and 44% of the children had an adherence ≥ 86%.