Analysis of an investigation results on iodine deficiency disorders in Gansu in 2009

Abstract

Objective To master the status in control of iodine deficiency disorders (IDD) in Gansu province and to provide the basis for development of control strategies. Methods One county which reached the national standardization of IDD elimination was selected randomly from each of 14 cities of Gansu province in 2009, then one town was selected respectively from five directions (east, south, west, north, and central) of the above selected counties. One village was chosen from every town which was selected for investigating household iodized salt and iodized salt sales network. At the same time the thyroid of children was examined, their urinary iodine (UI) was determined, the intelligence quotient(IQ) values of children were measured and health education was surveyed in one primary school which was chosen in each of the selected town. Results A total of 1420 edible salt samples were tested;the weighted iodized salt coverage rate and the weighted qualified iodized salt rate were 99.53% and 98.15 respectively. Urine samples were collected from 1761 children included in the study. The urinary iodine median was 225.87 μg/L. The urinary iodine medians were at optimal levels in five counties, over the optimal levels in seven counties and at excessive levels in two counties. A total of 3051 children aged 8 - 10 were randomly selected for thyroid examination. The weighted thyroid goiter rate(TGR) of children was 1.9%, and TGR was higher than 5% only in Hoaggu county. IQ of 2815 children was tested and the mean IQ was 105.3, except for the country of Zhuoni and Kangle, the mean IQ of other counties were over 100. The average score of health education was 3.2.Children of 57.08% (1229/2153) knew that iodine deficiency could lead to mental retardation, 71.76% (1544/2153) knew that iodine deficiency could cause thyroid goiter, 68.04%( 1465/2153 ) knew that eating iodized salt was the best method for IDD prevention and control and 61.82%(1331/2153) informed their families of the benefits of eating iodized salt. Each town had one agency selling iodized salt and each village had one more retail store with iodized salt, but 73.5%(75/102) of the stores without license for the sales. Conclusions Great progress has been made on the prevention and control of IDD in Gansu province. The qualified iodized salt consumption rate has reached the national standard for IDD elimination, TGR has decreased markedly, the urinary iodine levels in more counties are over the optimal levels and iodized salt distribution network is basically sound. But progress in health education is uneven. Key words: Iodine ; Deficiency disorders; Goiter, endemic ; Urine; Salts