Difference in goiter rates between two areas in Mae Hong Son province despite an equally sufficient iodine supply

Abstract

The study was designed to investigate the problem of endemic goiter and iodine supplementation in Mae Hong Son, Thailand. Routine school data still showed high goiter rates in many areas. Six such schools and five schools with declining prevalence of goiter were selected. A single examiner examined all the children. Their weight, height, body mass index, ethnicity, history of iodine intake and migration were recorded. Urine samples were collected for measuring iodine and thiocyanate levels. From 653 children, 105 and 13 were found to have grade 1 and 2 goiter status, respectively. Median values of urine iodine level in children from all schools suggested sufficient iodine supplementation. Multivariate analysis showed that hilltribe minorities had a 2.09 times higher risk of endemic goiter than Thai children. Urine thiocyanate levels among children from high prevalence schools were significantly higher than those from low prevalence schools. No other significant correlation was found. Possible roles of other known and unknown goitrogens should also be investigated.