ABSTRACT
OBJECTIVE: To document the population iodine nutritional status in Australian schoolchildren. DESIGN AND SETTING: Cross-sectional survey of schoolchildren aged 8-10 years, based on a one-stage random cluster sample drawn from all Year 4 school classes in government and non-government schools in the five mainland Australian states of New South Wales, Victoria, South Australia, Western Australia and Queensland. The study was conducted between July 2003 and December 2004. PARTICIPANTS: 1709 students from 88 schools (881 boys and 828 girls), representing 85% of the estimated target number of students. The class participation rate was 65%. MAIN OUTCOME MEASURES: (i) Urinary iodine excretion (UIE) levels (compared with the criteria for the severity of iodine deficiency of the World Health Organization/International Council for the Control of Iodine Deficiency Disorders: iodine replete, UIE > or = 100 microg/L; mild iodine deficiency, UIE 50-99 microg/L; moderate iodine deficiency, UIE 20-49 microg/L; severe iodine deficiency, UIE < 20 microg/L); (ii) Thyroid volumes measured by ultrasound (compared with new international reference values). RESULTS: Overall, children in mainland Australia are borderline iodine deficient, with a national median UIE of 104 microg/L. On a state basis, NSW and Victorian children are mildly iodine deficient, with median UIE levels of 89 microg/L and 73.5 microg/L, respectively. South Australian children are borderline iodine deficient, with a median UIE of 101 microg/L. Both Queensland and Western Australian children are iodine sufficient, with median UIE levels of 136.5 microg/L and 142.5 microg/L, respectively. Thyroid volumes in Australian schoolchildren are marginally increased compared with international normative data obtained from children living in iodine sufficient countries. There was no significant association between UIE and thyroid volume. CONCLUSION: Our results confirm the existence of inadequate iodine intake in the Australian population, and we call for the urgent implementation of mandatory iodisation of all edible salt in Australia.
Subject(s)
Iodine/deficiency , Age Factors , Child , Cluster Analysis , Cross-Sectional Studies , Female , Humans , Iodine/urine , Male , New South Wales , Nutrition Surveys , Queensland , Reference Values , Sex Factors , South Australia , Thyroid Gland/diagnostic imaging , Ultrasonography , Victoria , Western Australia , World Health OrganizationABSTRACT
Thyroid nodules are common clinically (prevalence, about 5%) and even more common on ultrasound examination (about 25%). About 5% of thyroid nodules are malignant. Most thyroid cancers are well-differentiated papillary or follicular tumours with an excellent prognosis (10-year survival, 80%-95%). The incidence of papillary thyroid cancer appears to be increasing on the east coast of Australia. Fine-needle aspiration biopsy of the thyroid is the most cost-effective diagnostic tool. Recommended initial management of all follicular carcinomas and of papillary carcinomas > 1.0 cm is total thyroidectomy followed by radioiodine ablation. Most patients should be managed postoperatively with doses of thyroid hormone sufficient to suppress plasma levels of thyroid-stimulating hormone. Recurrences can occur many years after initial therapy, and follow-up should be lifelong. Thyroid nodules are very common, but have a relatively low risk of malignancy
