Authors: Heydon EE, Thomson CD, Mann J, Williams SM, Skeaff SA, Sherpa KT, Heydon JL
Citation: Public Health Nutr 2009 Sep;12(9):1431-6
PMID : 19105860, Journal: Public Health Nutr, 12, 9
Date created: 2009-08-06
OBJECTIVE: To assess the iodine status of Sherpa residents living in Kunde village, Khumbu region, Nepal.
DESIGN: Prevalence of goitre was determined by palpation. Urinary iodine concentrations (UIC) were determined in casual morning samples, and thyroid-stimulating hormone (TSH) in finger-prick blood samples on filter paper. Dietary and demographic data were obtained via questionnaire, and selected foods analysed for iodine.
SETTING: Khumbu region is an area of low soil iodine in Nepal, where the prevalence of goitre was greater than 90% in the 1960s prior to iodine intervention.
SUBJECTS: Two hundred and fifteen of 219 permanent residents of Kunde were studied.
RESULTS: Overall prevalence of goitre was 31% (Grade 1 goitre, 27.0%; Grade 2, 4.2%). When adjusted to a world population, goitre prevalence was 27% (95% CI 23, 32%); Grade 2 goitre prevalence was 2.8% (95% CI 1.0, 4.6%). Median UIC was 97 microg/l, but only 75 microg/l in women of childbearing age. Thirty per cent had UIC < 50 microg/l and 52% had UIC < 100 microg/l, while 31% of children aged 300 microg/l. Ten per cent of participants had TSH concentrations >5 microU/ml.
CONCLUSIONS: The prevalence of severe iodine deficiency has decreased since the 1960s, but mild iodine deficiency persists, particularly in women of childbearing age. The consumption of high-iodine uncooked instant noodles and flavour sachets by school-aged children contributed to their low prevalence of goitre and excessive UIC values. This finding may obscure a more severe iodine deficiency in the population, while increasing the risk of iodine-induced hyperthyroidism in children. Ongoing monitoring is essential.