The goitre prevalance and urinary iodine status of primary school children in Lesotho

[摘要] English: Iodine deficiency has been called the world's most significant cause ofmental retardation. Studies conducted since 1960 have indicated iodinedeficiency as public health problem in Lesotho. The ICCIDD has beeninstrumental in focusing the world's attention on 100 and the goal of virtualelimination of 100 as a public health problem by the year 2000 wasaccepted by the united systems in 1990. This goal was reaffirmed by thee World Health Assembly in 1993, which also provided a strategicguidance including emphasis on salt iodisation.The main objective of this study was to estimate the current 100 situation inLesotho 5 years after the 1993 National Micronutrient Survey which wasfollowed by iodised oil capsule supplementation as a short term interventionand the introduction of the legislation on universal salt iodisation as a longterm intervention.This was a cross sectional study where stratified random sampling wasused to select 5 schools in each of the 10 districts of Lesotho. All childrenaged 8 to 12 years from the selected schools participated in the study. Thesize of the thyroid gland was determined by palpation and graded accordingto the Joint criteria of the WHO/UNICEF/ICCIDD (1994). Casual urinesamples were obtained from 10 children in each school in the morningduring school hours and frozen until they were analysed for urinary iodinelevel using the Sandell-Kolthoff reaction involving alkaline ashing at theNational University of Lesotho. Using a structured questionnaire, iodised oilsupplementation coverage was determined. Salt samples brought bychildren were also analysed for the presence of iodine using the rapid (spot)test kits. The SAS package was used for statistical analysis of the resultsat the University of Orange Free State. 4071 primary school children were palpated and responded to thequestionnaire, 4071 salt samples and 500 urine samples were analysed.The median urinary iodine concentration of 26.3IJg/l, which ranged from22.3IJg/1to 47.91Jg/l and from 25.7IJg/1 to 27.2IJg/1 in the different districtsand ecological zones respectively, indicated moderate 100. Theprevalence of goitre, which increased with age and was higher in femalesthan males, ranged from 2.2 to 8.8 percent and from 2.3 to 6.3 percent inthe different districts and ecological zones respectively indicating mild tonormal iodine deficiency. The adjusted prevalence of goitre for the wholecountry was 4.9 percent, indicating the absence of 100. 94.2 percent of saltsamples were iodised. Coverage on iodised oil capsules supplementation,which was 55.1 percent, was not adequate.Lesotho was found in this study as having mild to moderate 100, which isstill of public health concern according to WHO/UNICEF/ICCIOO (1994).Iodine deficiency was higher in the Mountains than in the Lowlands.However there is an improvement in controlling 100 in Lesotho as observedfrom the results of the present study and those of the previous studies. Theuse of iodised salt and iodised oil capsules has most likely contributed to adecrease in the 100 prevalence.Similar studies using ultrasonography and the titration method need to beconducted in the future. More iodised oil supplementation is recommendedin the Mountains and in schools, which never received the capsules andthis needs to be coupled with efficient awareness programs. An effectivemonitoring program needs to be initiated to ensure that the entirepopulation use adequately iodised salt.

[发布机构] University of the Free State