Iodine intake in Portugal: preliminary results in pregnant women
Edward Limbert1, Susana Prazeres1, Ana Miranda1, João Castro2, Francisco Carrilho3, Henrique Reguengo4 & Fatima Borges4
Introduction: Iodine is the key element for the synthesis of thyroid hormones and its intake modulates the physiology and physiopathology of thyroid gland. In Portugal, endemic goiter has disappeared, but some data make us consider that iodine intake, as in other European areas, is far from being sufficient. Taking into account the potential harmful effects of moderate iodine deficiency during pregnancy, when needs are increased, and the absence of recent data on iodine intake in Portugal, a countrywide study on urine iodine was undertaken. Preliminary results of this on going study from pregnant women are presented
Material and Methods: Target Population-Pregnant women from maternity hospitals and school children from strategic geographical areas (coast line and inland);1911 urines from 8 maternity hospitals were analysed.
Urinary iodide-A fast colorimetric method (Gnat et al, Clin Chem 2003) is being used
Statistical methods-Central methods and proportional comparison tests
Global Results: Median urinary iodide concentration was 88.9 μg/L, being 21.3% below 50 μg/L.19% had values above. 150 μg/L
Results by Hospital: Median urinary iodine varied from 78 to 124 μg/L; 13.9% to 29.6% of women had values below 50 μg/L and 12.5 to 34% had values above 150 μg/L In South Portugal the proportion of women with values below 50 μg/L was significantly lower in Greater Lisbon than in other cities.
Conclusions: Although this results are preliminary they point out to an inadequate iodine intake in pregnant women, from most Portuguese regions. Considering these preliminary results the on going study needs to be completed (data from pregnant women and also from school children) and more detailed analysis is warranted in order to explain the observed differences between regions. Taking into account the potential deleterious effects of inadequate iodine supply during pregnancy, iodine supplementation is recommended in this period of life.