Potential Preventive Effect of Selenium on Iodine-induced Thyroid Autoimmunity During Pregnancy

NCT03377218 | Unknown

• 1 other identifier: RigaStradinsU_Iodine3
• Study Type: interventional
• Target: 300
• Locations: 1 country
• Sites: 1

Brief Summary

In 1994, the WHO and UNICEF Joint Committee on Health Policy recommended Universal Salt Iodization as a safe, cost-effective and sustainable strategy to ensure sufficient intake of iodine by all individuals. However, it is still absent in Latvia. A recent countrywide study in 2013 shows iodine deficiency among pregnant women in Latvia: 81 % of pregnant women had UIC levels below the WHO recommended range of 150-250 mcg/g Cr. Because mild to moderate iodine deficiency during pregnancy can adversely affect fetal brain development, WHO-UNICEF and ICCIDD advise an increase in the recommended daily dosage of iodine to 250 mcg/day for pregnant women and breastfeeding women and 150 mcg/day for women in the preconception period. Data from a survey of the Latvian population indicate that approximately 100 mcg of iodine per day is consumed through foods and iodized salt. To meet the increased iodine requirement in pregnancy, pregnant women should take a supplement containing 150 mcg of iodine daily from the earliest time possible. A sudden increase in iodine intake in an iodine-deficient population may increase thyroid autoimmunity. It is evident that thyroid disease has multiple adverse effects during pregnancy and in the developing fetus especially in women with elevated serum anti-thyroid antibody titers. Studies have considered supplementing with selenium to reduce the risk of auto-immune thyroiditis/post-partum autoimmune thyroid disease. Of the 11 trials of selenium supplementation in patients with autoimmune thyroiditis, 7 have shown benefit with treatment for 6 months or longer. Aim of study is to approve that 150 mcg of iodine daily improves iodine status in pregnant women and iodine 150 mcg in combination with selenium 100 mcg daily reduce risk of thyroid autoimmunity. Hypothesis of study is that 150 mcg iodine daily during pregnancy improves iodine status. Iodine in combination with selenium is less associated with thyroid autoimmunity. Study design: Pregnant women are randomized for either 150 mcg iodine intake daily or 150 mcg iodine combined with 100 mcg selenium daily. Interventional group is compared with controls without particular iodine supplementation. Participants are asked to complete a questionnaire on dietary habits concerning iodine. Thyroid function (thyroid-stimulating hormone, free thyroxine) and thyroperoxidase antibodies (TPO-Ab) and urinary iodine are measured during first, second and third trimester of pregnancy and week 8 after delivery in both, intervention and control group.

Conditions

Pregnancy; Thyroid Autoimmune Disease; Iodine Deficiency; Selenium Deficiency

Outcome Measures

Primary Outcomes (2)

• UIC

  Urinary iodine concentration

  At baseline - 9/10 weeks of gestation, second sample - 24 weeks of gestation (14 weeks from baseline), third sample - 34 weeks of gestation (24 weeks from the baseline) and fourth sample - 8 weeks postpartum- (38 weeks after the baseline sample)

• Change in anti-TPO Ab

  Change in anti-thyroperoxidase antibodies

  At baseline - 9/10 weeks of gestation, second sample - 24 weeks of gestation (14 weeks from baseline), third sample - 34 weeks of gestation (24 weeks from the baseline) and fourth sample - 8 weeks postpartum- (38 weeks after the baseline sample)

Secondary Outcomes (2)

• TSH

  At baseline - 9/10 weeks of gestation, second sample - 24 weeks of gestation (14 weeks from baseline), third sample - 34 weeks of gestation (24 weeks from the baseline) and fourth sample - 8 weeks postpartum- (38 weeks after the baseline sample)

• fT4

  At baseline - 9/10 weeks of gestation, second sample - 24 weeks of gestation (14 weeks from baseline), third sample - 34 weeks of gestation (24 weeks from the baseline) and fourth sample - 8 weeks postpartum- (38 weeks after the baseline sample)

Study Arms (3)

Control

NO INTERVENTION

Without additional iodine supplementation.

Iodine

EXPERIMENTAL

Receiving iodine.

Dietary Supplement: Iodine

Iodine + Selenium

EXPERIMENTAL

Receiving iodine and selenium.

Dietary Supplement: Iodine + Selenium

Interventions

Iodine DIETARY_SUPPLEMENT

Receiving 150 μg iodine (as potassium iodide) daily

Iodine

Iodine + Selenium DIETARY_SUPPLEMENT

Receiving a combination of 150 μg iodine (as potassium iodide) and 100 μg selenium daily

Iodine + Selenium

Eligibility Criteria

• Age: 18 Years+
• Sex: female
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• healthy women before 10 weeks of gestation
• signed informed consent form

You may not qualify if:

• pre-existing thyroid disease
• pregnancy after assisted reproductive technologies
• known hypersensitivity reaction to iodine or selenium, or other components of dietary supplement used in the study

Sponsors & Collaborators

• Riga Stradins University: lead
• Latvian Biomedical Research and Study Centre: collaborator
• Riga Maternity hospital: collaborator
• Latvian Institute of Organic Synthesis: collaborator

Study Sites (1)

Riga Maternity hospital

Riga, Latvia

RECRUITING

MeSH Terms

Interventions

Iodine; Selenium

Intervention Hierarchy (Ancestors)

Halogens; Elements; Inorganic Chemicals; Chalcogens; Minerals

Study Officials

• Ilze Konrade, professor

  Riga Stradins University

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Ilze Konrade, professor

CONTACT

29140141; drkonrade@inbox.lv

Vija Veisa, doctor

CONTACT

26442100; vijaveisa@inbox.lv

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: associate professor

Study Record Dates

• First Submitted: November 18, 2017
• First Posted: December 19, 2017
• Study Start: January 5, 2018
• Primary Completion: December 1, 2018
• Study Completion: January 1, 2019
• Last Updated: April 19, 2018

Record last verified: 2018-04

Locations

LA (1)