Median urinary iodine concentration reflected sufficient iodine supply in neonates from Northeast Germany in 2005-2006.

PURPOSE: Data from recent adult studies suggest a decline of median urinary iodine concentrations (UIC) in Germany, but since 1996 no German study investigated UIC in neonates. The aim of our study was to investigate UIC and serum thyroid-stimulating hormone (TSH) levels in neonates from Germany. METHODS: We used data from 399 neonates, which were born between April 2005 and November 2006 in the Northeast of Germany. UIC were evaluated by a photometric procedure with Sandell and Kolthoff reaction and afterwards corrected to be comparable with an ICP-MS method. TSH was determined from capillary blood, which was taken within 5 days after birth, by DELFIA. RESULTS: Median UIC were 150 µg/L (25th percentile: 104 µg/L; 75th percentile: 196 µg/L) and differed between boys (153.3 µg/L) and girls (131.5 µg/L; p = 0.012). The prevalence of serum TSH levels > 5 mIU/L was 14%. Neonates from mothers with intake of iodine supplementation (150 µg/L) had significantly higher median UIC than neonates from mothers without iodine supplementation (132 µg/L; p = 0.011). Multivariable linear regression adjusted for sex and iodine supplementation of the mother revealed a significant association between UIC and log-transformed serum TSH levels (ß = 0.003: 95% confidence interval (CI) = 0.0001-0.005; p = 0.028). CONCLUSIONS: Neonates in Northeast Germany did show a sufficient supply of iodine. This points towards the possibility of a sufficient iodine supply of neonates also in other regions of Germany, even though recent studies in adults may indicate mild iodine deficiency.

Association of socioeconomic status with iodine supply and thyroid disorders in northeast Germany.

OBJECTIVES: Studies on the potential association of socioeconomic status with iodine supply and the risk for thyroid disorders from developed countries are sparse. Socioeconomic status, however, may particularly impact the efficiency of iodine prophylaxis programs, which are based on the voluntary principle. This study aims to investigate whether the socioeconomic status is cross-sectionally and longitudinally related to low urinary excretion or thyroid disorders in the population of northeast Germany. METHODS: Data of the population-based Study of Health in Pomerania were used. The study population comprised 4056 adults for cross-sectional and 2860 adults for longitudinal analyses. Assessment of socioeconomic status comprised different scales of education, income, employment, and occupation. Thyroid-related outcomes included urinary iodine excretion, serum thyrotropin, and sonographically defined goiter and nodules. Statistical analyses were adjusted for confounders. RESULTS: Some of the socioeconomic variables were associated with thyroid-related characteristics in cross-sectional analyses. For example, there was an overall tendency for groups with higher education and higher income to have larger thyroid volumes and an increased risk of goiter. However, most of these associations did not attain statistical significance after correcting the target p-value for multiple testing. Longitudinal analyses did not demonstrate consistent results. CONCLUSIONS: Socioeconomic status neither substantially influences iodine supply nor does it have a major impact on the prevalence and incidence of thyroid deficiency-related disorders in the adult population of northeast Germany, indicating a good efficacy of the German iodine fortification program in all socioeconomic groups.