Iron and iodine supplementation in school children in Ngargoyoso sub-district, Karanganyar regency, Central Java, Indonesia

Background: Schoolchildren living in iodine deficient area are not only vulnerable to iodine deficiency, but also to other micro-nutrient deficiencies. Recent screening on hematologic status in Ngargoyoso sub-district showed very high prevalence of anaemia among school children. Objectives: The present study was designed to test hypothesis that adding iron to iodine supplementation will improve both iodine and hematologic status in schoolchildren living in IDD endemic area. Methods: Three hundred and sixty five school children from year three (± 8 years old) from 22 state-owned elementary schools in Ngargoyoso sub-district were clustered-randomly assigned into two groups. The first group (N=211)) received 60 mg elemental iron (200 mg FeSO4) twice weekly and 100 µg iodine (KIO3) daily via drinking water, for six weeks. The second group (N=154) received 60 mg elemental iron (200mg FeSO4) six days a week and 100 µg iodine (KIO3) daily via drinking water, for six weeks. Both groups received Albendazole 400 mg given in single dose, before starting supplementation. Hemoglobin concentration was measured using haematin-chloride (Sahli) method. Urinary iodine excretion (UIE) was measured using Method A (ammonium persulfate) in an accredited IDD Laboratory in Magelang, Central Java, Indonesia. Goitre prevalence was measured by palpation method. Total goitre rate (TGR) is the sum of grade 1 and grade 2. Statistical analysis was performed using SPSS for Windows release 17.0 (Chicago, IL, USA). Results: Before treatment 98.6% of schoolchildren (N = 365) were anemic (Hb<11,5 g/dl). Median urinary iodine excretion (UIE) was 248.5 µg/L, but 14.6% were below 100 µg/L. After six weeks supplementation hemoglobin concentration increased from 9.827 ± 0,719 g/dl in group one to 10.183 ± 0.742 g/dl, whereas in group two there was an increased in hemoglobin concentration from 9.645 ± 0.591 g/dl to 10.196 ± 0.611 g/dl. Median UIE also increased from 248.5 µg/L to 319 µg/L after six weeks supplementation. The proportion of schoolchildren with UIE less than 100 µg/L also decreased from 14.6% to 7.5%. The difference between groups was significant. Total goitre rate (TGR) was 9.3% at basal, and a follow up is needed. Conclusion: Adding iron to iodine supplementation via drinking water was effective in improving hemoglobin status and iodine intake among school children in Ngargoyoso sub-district, Karanganyar regency, Central Java Province, Indonesia. Keywords: iron, iodine, hemoglobin, urinary iodine excretion