ABSTRACT
Objective To study the consumption rate of qualified iodized salt at household level based on the salt surveillance results from 2004 to 2011,and to provide a scientific basis for setting up appropriate control strategies to iodine deficiency disorders.Methods Iodized salt monitoring results in Hainan Province from 2004 to 2011 were collected with retrospective method.Coverage rate of iodized salt,qualified rate of iodized salt and consumption rate of qualified iodized salt were calculated at the provincial,city(county) levels and on geographic distribution (coastal,plains and mountains).Qualified iodized salt criteria was set as (35 ± 15)mg/kg,unqualified iodized salt criteria was set as 5 to ＜ 20 mg/kg or ＞ 50 mg/kg,and criteria of non-iodized salt was set as ＜ 5 mg/kg.Results From 2004 to 2011,at provincial level,the median of iodized salt was raised from 30.25 mg/kg to 32.14 mg/kg; the iodized salt coverage rate,the qualified rate of iodized salt and the consumption rate of qualified iodized salt was raised from 77.81％ (4780/6143) to 96.06％ (5890/6132),90.48％ (4325/4780) to 98.72％(5815/5890),and 70.41％(4325/6143) to 94.83％(5815/6132),respectively.From 2004 to 2011,at city (county) level,the proportion of iodized salt coverage rate that higher than 90.00％,of qualified rate of iodized salt that higher than 95.00％ and of consumption rate of qualified iodized salt that higher than 90.00％ was raised from 44.45％(8/18) to 88.89％(16/18),16.67％(3/18) to 100.00％(18/18),and 22.22％(4/19) to 88.89％(16/18),respectively.The iodized salt coverage rate in the coastal and plain townships was raised from 70.55％(1440/2041) to 95.02％(1869/1967),and 75.36％ (1762/2338) to 96.24％(2331/2422),respectively.The iodized salt coverage rate in mountainous townships maintained at 89.46％ (1578/1764)-97.46％ (1690/1734) in the 8 years.There were 2 counties where the iodized salt coverage rate was less than 90％.There were 9 and 4 townships,where the iodized salt coverage rate was less than 90％ in coastal and plain townships,respectively,in 2011.Conclusions The rate of qualified iodized salt has been raised in Hainan Province,but part of coastal and plain townships (towns) are still serious in non-iodized salt problem.Comprehensive intervention on iodine deficiency disorders should be strengthened in these areas.
ABSTRACT
Objective To estimate the impact of universal salt iodization on child intelligence quotient (IQ) development in Hainan province. Methods In this is a cross-section study from September in 2008 to April in 2009,the observation group was historical iodine deficiency ward which includes 2 counties and 6 townships,and the control group was non-historical ward which includes 6 counties and 9 townships. Comparison of child IQ distribution according to different geographical housing position(plain,mountainous area,coast),age and sex based on the result of urine iodine examination and the IQ test of children between 8 and 10 years old. Results The median of urinary iodine of children in the observation group was 196.2μg/L which was 2.13 times of the urinary iodine median in the control group(91.9μg/L). The average IQ of children in the observation group was 94.7 which was 8.5 higher than the control group(86.2) ; IQ≤69 rate in this group was 7.7%(91/1179),and it was 8.9 percentage point lower than the control group[16.6%(253/1520)]; IQ≥ 110 rate of the group was 18.3%(216/1179),and it was 10.0 percentage point higher than the control group[8.3%(126/1520)]. The average IQ of children living in mountainous area(83.1) was the lowest in the control group. It was 3.5 and 5.1 lower than that of the children living in the plain(86.6) and coastal area(88.2) respectively; the IQ≤69 rate of children living in mountainous area [20.5%(91/443)]was the highest,and it was 3.8 and 7.1 percentage point higher than that of the children living in the plain [16.7% (89/533)]and coastal areas [13.4% (73/544)]respectively. The average IQ of children aged 8 (97.4) was similar to those aged 9(95.9) in the observation group which was 6.8 and 5.3 higher than that of the children aged 10(90.6) in the same group respectively; However,the average IQ of children aged 8,9 and 10 was close in the control group(86.8,86.3 and 85.6). The average IQ of boys(96.2) was 3.1 higher than that of the girls(93.1),and their IQ≤69 rate[6.3%(37/590)]was 2.9 percentage point lower than that of the girls[9.2% (54/589)]in the observation group. On the other hand,the average IQ(87.2) of boys was 2.1 higher than that of the girls(85.1),and IQ≤69 rate[14.5%(114/787)]was 4.5 percentage point lower than that of the girls [19.0%(139/733)]in the control group. The average IQ of children with different housing geographical position,age and sex in observation group was 5.0-12.4 higher than that of the control group; their IQ≤69 rate was 7.7-13.2 percentage point lower than that of the control group; their IQ≥110 rate was 5.6-13.0 percentage point higher than that of the control group. Conclusions Supplementing salt iodization can improve child intelligence. Supplementing iodine can increase the child IQ and reduce the child mental retardation.
ABSTRACT
Objective To know the prevalence of iodine deficiency disorders(IDD) and the implementation of control measures against the disorders in high-risk areas of Hainan province. Methods Typical sampling principle was used. Eight townships with lower coverage rate of iodized salt were chosen in IDD high-risk counties of Hainan. New cretinism cases were screened among children aged 10 years and under. Intelligence quotient (IQ)value, urinary iodine (UI) concentration and thyroid gland size (by palpation and B ultrasonic) were investigated in children aged 8 to 10 years and questionnaire was also carried out among students from grade 5 in elementary school. Edible salt and urine of women of childbearing age were collected to detect iodine levels, respectively,questionnaire was also carried out among the women of childbearing age. The UI was determined by As3-Ce4+ catalytic spectrophotometer, the salt iodine level was determined using self-quantitative kit. IQ values were measured by the Combined Raven Test in China (CRT-C2). Results Seventy-two townships were investigated in three consecutive years, 7937 children aged 8 to 10 years, 1797 women of childbearing age and 4128 students of grade 5 were included in the survey. One child was diagnosed as suspected new cretinism case. The coverage rate of iodized salt was increased from 44.6%(629/1411) in 2007 to 92.1%(1688/1832) in 2009. The goiter rate was dropped from 5.9% (269/4548), 6.0% (274/4548) in 2007 to 1.6% (24/1461), 0.1% (2/1461) in 2009 bypalpation, and by B-ultrasound, respectively, in children aged 8 to 10 years. The median urinary iodine(MUI) was found to be increased from 97.4 μg/L in 2007 to 165.0 μg/L in 2009, and the percentage of UI less than 50.0 μg/L, and 100.0 μg/L were dropped from 21.4%(973/4548), 51.2%(2329/4548) in 2007 to 7.5 %(110/1461), 23.4%(342/1461) in 2009, respectively. The MUI of women of childbearing age was found to be elevated from 73.7 μg/L in 2007 to 126.1 μg/L in 2009, and the value was also increased from 55.7 μg/L to 121.5 μg/L in pregnant women, but these values were still lower than 150.0 μg/L The pass rate of the questionnaire of IDD controlling among the students of grade 5 and the women of childbearing age was raised from 29.8% (446/1495) ,24.1% (179/742) in 2007 to 65.8%(732/1112), 72.1%(264/366) in 2009, respectively. The mean IQ of children was 90.4±16.0, and the percentage of IQ value less than 69 was 12.6% (1000/7937). Conclusions The diseased state of IDD has improved in the high-risk counties of disorders in Hainan province, but the pregnant women are still iodine deficient. Iodine supplimentation should be promoted among pregnant women.