The Results of 16 Years of Iodization: Assessment of Iodine Deficiency Among School-age Children in Antalya, Turkey

A 10-Year Impact Evaluation of the Universal Salt Iodization (USI) Intervention in Sarawak, Malaysia, 2008–2018

A universal salt iodization (USI) was introduced in Sarawak, Malaysia in 2008 to control the iodine deficiency disorders (IDD) among its population. The purpose of this study is to evaluate the impact of the USI among school children in Sarawak after 10 years of implementation. The data were extracted from 2008 and 2018 Sarawak state-wide IDD surveys. Briefly, both surveys were cross-sectional surveys covering information on the socio-demographic, status of goitre, urinary iodine, and the amount of iodine in the salt samples. A total of 1104 and 988 between the ages of 8 and 10 were involved in the 2008 and 2018 surveys, respectively. The overall prevalence of goitre among the school children in Sarawak was significantly lower in 2018 (0.1%) compared to 2008 (2.9%). The median urinary iodine concentration (UIC) in urine samples had risen significantly from 102.1 µg/L in 2008 to 126.0 µg/L in 2018. In terms of iodine content in salt samples, the median concentration improved significantly in 2018 (35.5 µg/L) compared to 2008 (14.7 µg/L). After 10 years of USI implementation in Sarawak, the results from both surveys confirmed the effectiveness of mandatory USI in increasing the nutritional iodine status of school children in Sarawak.

Assessment of the Impact of Salt Iodisation Programmes on Urinary Iodine Concentrations and Goitre Rates: A Systematic Review

Introduction

Two main strategies are currently recommended for the prevention and control of iodine deficiency in the world: implementation of universal salt iodisation programmes and permanent monitoring of iodine consumption by the population. Although iodine intake and coverage iodised salt have increased in the world population, iodine deficiency disorders (IDDs) may still be a public health problem in a few countries or communities.

Objective

To assess the impact of salt iodisation programmes on urinary iodine concentrations and goitre rates in the world population. Methodology. A systematic review based on the PRISMA method. We obtained articles from Scopus, Science Direct, MEDLINE databases, and other sources between March and April 2020, without limitation of dates. "Iodisation" AND "urinary iodine concentrations" AND "goitre" in English, Portuguese, and Spanish without filters and clinical trial, case-control, and cross-sectional studies were included in this review.

Results

Of 479 abstracts, twenty-three were eligible. Coverage on iodised salt was in the range of 16 to 98%, and 11 studies had been sufficient, whilst eight studies had adequate iodine concentration in salt and three excess. 81.8% of studies that had an adequate median of UIC had a good impact in their respective salt iodisation programmes.

Conclusion

After 18 years of salt iodisation programme implementation in the 13 countries, the majority achieved sustaining elimination of IDD whilst all had adequate median UIC; however, more detailed studies are still needed to confirm that all communities are equally protected of IDD.

Bilateral retinal toxicity as a result of poisoning with pure iodine

Iodine is an essential mineral that is necessary for the synthesis of thyroid hormones, which can cause many diseases in the body. The application of adding potassium iodate to table salts started in Turkey in 1998. High doses of iodate cause retinal toxicity, leading to significant vision loss. A 42-year-old paranoid schizophrenic patient who attempted suicide with pure iodine was admitted with bilateral vision loss. Widespread retinal pigment epithelium (RPE), ellipsoid zone (EZ) and interdigitation zone (IZ) damage were present in the optical coherence tomography (OCT) assessment. Fundus autofluorescence (FAF) findings, which included hypoautofluorescence areas that supported this condition, were also found. In conclusion, iodate in high doses is toxic on RPE, EZ and IZ. This situation could be irreversible depending on the dose.