EUthyroid2: the Next Step Towards the Elimination of Iodine Deficiency and Preventable Iodine-related Disorders in Europe

BACKGROUND: Iodine deficiency (ID) is a leading risk factor for the development of thyroid disorders, of which in particular women are affected. During pregnancy, ID can increase the risk of developmental disorders in the offspring, however, it is considered as one of the most preventable causes of mental impairment in children. Therefore, the EUthyroid2 project aims to contribute to the prevention of ID and associated symptom and disease burden in adolescence and young women in Europe and beyond.

AIM: An educational intervention is to be developed, implemented in ambulatory care settings and evaluated to effectively raise awareness for the risks of ID among young women (18-24 years) in three European countries (Norway, Poland, UK) as well as Bangladesh and Pakistan.

METHODS: A cluster-randomised controlled trial is to be conducted in each of the five countries. 10 clusters per country (5 intervention group clusters and 5 control group clusters) are planned to achieve a final sample size of 200 study participants per implementing country with one baseline (before the intervention) and two follow-up measurements (2-4 weeks and 6-8 months after the intervention). In all, 1000 participants are to be recruited and data for all measurement points collected. Due to differences in the healthcare systems, the ambulatory care units, where the intervention will be implemented, may vary across the countries. Before recruiting the women, the healthcare professionals who carry out the intervention will receive a specially designed training program. To assure the intervention's functionality and effectiveness, recommendations for the development of complex interventions, appropriate theories and frameworks will be considered and a context analysis will be conducted. The primary outcome of the study is iodine awareness and knowledge measured by a newly developed questionnaire. Other outcomes includes measurement of iodine status (urinary iodine concentration), intake of dietary iodine sources (measured by a food frequency questionnaire), and iodine related behaviours. Sociodemographic characteristics and general dietary habits will also be measured. Descriptive analyses for all variables will be performed. Intervention groups will be compared to control groups over time to test effectiveness. Subgroup and country-specific analyses will also be computed. A process evaluation will be conducted to evaluate the implementation process with a convergent parallel mixed methods design. For this, healthcare professionals in the ambulatory care settings and the women who received the intervention will be invited to participate in an online survey. Further, ca. 20-30 semi-structured interviews will be conducted with women and healthcare professionals.

CONCLUSION / OUTLOOK: The project results may support health authorities across countries to implement effective measures to reduce ID and associated risks. This may sustainably reduce the disease burden induced by ID for young women, pregnant women and their offspring.

• Significant change in the urinary iodine status of women (18-24 years) within the intervention group from T1 (baseline) to T2 (2-4 weeks) or T3 (6-8 months) and compared to women (18-24 years) in the control group [Time frame: T1 = baseline (before the intervention); T2 = first follow-up (2-4 weeks after the intervention); T3 = second follow-up (6-8 months after the intervention)]
• Significant change in intake of dietary iodine sources of women (18-24 years) within the intervention group from T1 (baseline) to T2 (2-4 weeks) or T3 (6-8 months) and compared to women (18-24 years) in the control group [Time frame: T1 = baseline (before the intervention); T2 = first follow-up (2-4 weeks after the intervention); T3 = second follow-up (6-8 months after the intervention)]
• Significant change in awareness of iodine of healthcare professionals before (T1) and after the training (T2) [Time frame: T1 = baseline (before the training); T2 = follow-up (2-4 weeks after the training)]
• Significant change in intake of dietary iodine sources of the healthcare professional before (T1) and after the training (T2) [Time frame: T1 = baseline (before the training); T2 = follow-up (2-4 weeks after the training)]