THYROID VOLUME AND URINARY IODINE IN EUROPEAN SCHOOLCHILDREN - STANDARDIZATION OF VALUES FOR ASSESSMENT OF IODINE DEFICIENCY

Up to 1992, most European countries used to be moderately to severely iodine deficient. The present study aimed at evaluating possible chang es in the status of iodine nutrition in 12 European countries during t he past few years. Thyroid volume was measured by ultrasonography in 7 599 schoolchildren aged 7-15 years in one to fifteen sites in The Neth erlands, Belgium, Luxemburg, France, Germany, Austria, Italy, Poland, the Czech and Slovak Republics, Hungary and Romania, The concentration s of urinary iodine were measured in 5709 of them. A mobile unit (Thyr oMobil van) equipped with a sonographic device and facilities for the collection of urine samples visited all sites in the 12 countries. All ultrasounds and all urinary iodine assays were performed by the same investigators, The status of iodine nutrition in schoolchildren has ma rkedly improved in many European countries and is presently normal in The Netherlands, France and Slovakia. It remains unchanged in other co untries such as Belgium. There is an inverse relationship between urin ary iodine and thyroid volume in schoolchildren in Europe. Goiter occu rs as soon as the urinary iodine is below a critical threshold of 10 m u g/dl. Its prevalence is up to 10 to 40% in some remote European area s. This work produced updated recommendations for the normal volume of the thyroid measured by ultrasonography as a function of age, sex and body surface area in iodine-replete schoolchildren in Europe. This st udy proposes a method for a standardized evaluation of iodine nutritio n on a continental basis, which could be used in other continents.