RESUMO
Objective To analysis the progress in prevention and control of iodine deficiency disorders (IDD) in Dalian and to provide a scientific basis for further prevention and control of the disease.Methods From 2006 to 2010,5 or 9 townships were randomly sampled from each county in Dalian,4 villages were sampled from each selected townships and 15 or 8 households were sampled from each selected villages for collecting salt samples and salt iodine level was determined by direct titration method.Sixty daytime urine samples from pregnant women,breast feeding women,infants and young children were collected,respectively,every year to detect urinary iodine level.From 2007 to 2009,2 to 11 counties were sampled and from each selected county one school was sampled to collect 100 daytime urine samples of children aged 8-10 and iodine content was determined.From 2006 to 2009,2 to 5 counties were sampled,from each selected county 2 to 5 schools were sampled and 100 children aged 8 to 10 in each selected school were sampled to detect intelligence quotient level and the thyroid volume.Results From 2006 to 2010,16 012 copies of households' edible salt samples were monitored; the average iodine content was ranged 29.68-31.51 mg/kg,the rate of qualified iodized salt in household ranged from 97.24％ to 98.42％.A total of 1398 copies of urine samples of pregnant women,486 breast feeding women,473 infants and 502 young children were monitored,and the median value of urinary iodine was 129.3-189.6,114.6-190.6,148.5-298.5 and 144.4-187.3 μg/L,respectively.A total of 1657 urine samples were monitored,1264 intelligence quotient level and 1197 thyroid volume of school-age children were determined,the median urinary iodine,thyroid goiter rate and intelligence quotient level was 217.9-266.7 μg/L,0-3.29％ and 110.4-117.2 μg/L,respectively.Conclusions From 2006 to 2010,the city's households qualified iodized salt coverage rate has reached the national standard for elimination of iodine deficiency disorders.The iodine nutrition of key population and school-age children has reached adequate level,the thyroid goiter rate is less than 5％,and the level of intelligence quotient has increased every year.But the iodine nutrition of breast feeding women in 2009 and 2010,pregnant women in 2010 is inadequate,so iodine nutrition surveillance and health education in pregnant and breast feeding women need to be strengthened in the future.
RESUMO
Objective To obtain scientific data for control of iodine deficiency disorders(IDD) by reviewing the surveillance information of school children intelligence quotient(IQ) after the implementation of universal salt iodization. Methods One thousand five hundred and eighty children were selected from 11 primary school in Dalian city of Liaoning province during 2006 to 2009. IQ was measured by Combined Raven Test-C2(CRT-C2) in China. Groups of IQ were classified as outstanding(≥ 130), excellent (120- 129), above average (110- 119), average (90 - 109), below average(80 - 89), margin(70 - 79), low(≤69). Urinary samples of children were collected randomly. Urinary iodine were determined by As-Ce catalytic spectrophotometry. The growth characteristics of IQ were analyzed according to surveillance year and born year. Results The average IQ of children aged 8-10 were 110.4 ± 14.0,112.5 ± 12.4,117.2 ± 11.4,116.2 ± 12.6, respectively, increased year by year from 2006 to 2009. Its average annual increase from 2007 to 2009 were 2.1,3.4,1,9 compared with the IQ in 2006 respectively. The medians of urinary iodine were 224.7,266.7,222.1 μg/L from the year 2007 to 2009, respectively, which were all between 200 - 300 μg/L and can be classified as more than adequate level. The average IQ of children born during the year of 1994 to 2000 were 106.7 ± 13.0,108.1 ± 13.9,108.5 ± 13.4,111.3 ± 14.3,113.6 ± 12.5,115.3 ± 12.3,119.8 ± 11.2, respectively. Its average annual increase from 1995 - 2000 were 1.4,0.9,1.5,1.7,1.7,2.2 compared with the IQ born in 1994 respectively. The ratio of IQ in margin group and low group were all below 2% ; the ratio was increasing in excellent group and outstanding group and decreasing in average group and below average group significantly year after year(x2 = 52.471,34.329,66.483,11.148, all P<0.01). Conclusions Universal salt iodization improves IQ scores. IQ index should be brought into the surveillance project and put in use in IDD control.