Iodine deficiency in Calabria: Characterization of endemic goiter and analysis of different indicators of iodine status region-wide

The distribution of goiter prevalence in schoolchildren (no.=13,984, age 6–14 yr), the neonatal TSH results obtained from the congenital hypothyroidism screening program and the urinary iodine excretion values (no.=284) were employed for the assessment of iodine deficiency in Calabria, a Southern Italy region. Data were collected during the years 1990–1996. In the inland territory, goiter prevalence ranged from 19 to 64%. At sea level, there was a great variability of goiter prevalence, with values varying from 5.3 to 25.7%. The analysis of the neonatal hypothyroidism screening program data (no.=21,078) showed a 14.8% frequency of TSH levels >5 μU/ml whole blood in newborns from the inland territory and a 14.1% frequency at sea level. Urinary iodine excretion resulted (mean±SD) 53.8±43.4 μg/l (range: <20 to 189 μg/l) in the inland territory and 89.6±59.8 μg/l (range: 26 to 333 μg/l) at sea level. Median urinary iodine excretion values in 13 villages or small towns of the inland territory ranged from 31 to 57 μg/l. In 2 major towns located at sea level, the median iodine excretion values were 72 μg/l in Crotone main city and 94 μg/l in Reggio Calabria main city. The data indicated that moderate, with pockets of severe iodine deficiency is present in the inland region while iodine supply varies from sufficient to marginally low in the coastal areas. Mild iodine deficiency was found in a major town located at sea level.