Does a small difference in iodine status among children in two regions of Belgium translate into a different prevalence of thyroid nodular diseases in adults?

Purpose: To explore whether there are regional differences in iodine status and in prevalence of thyroid diseases in the two main regions of Belgium.
Methods: A national survey of iodine status among children was performed in 1998. The raw data of this survey were reanalyzed to explore regional differences. The total number of thyroidectomies, carried out for multinodular goiter or solitary nodules, was obtained from the Minimal Clinical Summary hospital discharge database. Percentage of people with thyroid diseases going to the general practitioner or the specialist was assessed by means of data about the number of adults using anti-thyroid medications. Food consumption patterns were explored using national food consumption data.
Results: In Flanders, median urinary iodine concentration (UIC) was higher than in Wallonia, 84 μg/L (n = 1,316) and 78 μg/L (n = 1,268), respectively (p < 0.001). There were no differences in goiter prevalence and thyroid volume between the regions among children. Data from the food consumption survey showed a significant higher consumption of seafood in Flanders compared to Wallonia. Further, it was observed that the number of thyroidectomies, carried out for MNG or solitary nodules, and the use of anti-thyroid medication were significantly higher in Wallonia than in Flanders.
Conclusion: Iodine status in children was found slightly different in both regions of the country. This finding is in agreement with a higher incidence of thyroidectomies and more extensive use of anti-thyroid medications in the adult population in the region with the lowest iodine excretion.