Iodine Status in Europe in 2014

Iodine deficiency has been recognised as a worldwide problem since the last century [1]. The International Council for Iodine Deficiency Disorders Global Network (ICCIDD GN) has underpinned remarkable progress in ameliorating this problem during the last nearly 30 years and especially during the last decade [2]. The number of iodine-deficient countries in the world has decreased from 54 in 2003 to 47 in 2007 and 32 in 2011 [3]. This remarkable rate of progress has been largely due to intensive work by the ICCIDD GN, UNICEF and WHO. Nevertheless, of these 32 countries, 11 (34%) are in Europe, the largest number from any continent [3]. West and Central Europe has a total population of about 600 million situated in 35 countries (table 1), with country populations ranging from 0.3 to 75 million. Attention was drawn to the iodine deficiency problem in this area more than 10 years ago [4]. In general, the iodine deficiency is mild, but nevertheless this may have an impact on childhood development. For example, mild-to-moderate iodine deficiency in the first trimester of pregnancy was associated with increased odds of the intelligence quotient of offspring being in the lowest quartile (odds ratio: 1.43; 95% CI: 1.04-1.98; p = 0.03), with the greatest negative impact observed with the verbal intelligence quotient (odds ratio: 1.66; 95% CI: 1.20-2.31; p = 0.002) [5]. A review of the current evidence indicates that a correction of mild-to-moderate iodine deficiency improves cognitive performance in school-age children, but there are insufficient data on developmental outcomes in early life [6]. There are 2 randomised studies of iodine supplementation in children with mild iodine deficiency in Albania [7] and New Zealand [8] showing improved cognition. However, large-scale controlled trials are now needed to clarify whether gestational iodine supplementation will benefit infant and childhood neurodevelopment in more European countries with marginal iodine deficiency.