Study on the Relationship Between Iodine Nutrition and Thyroid Diseases in the Elderly

The aging trend of China's population is intensifying. More than 50% of the elderly in China suffer from thyroid disease. Thyroid dysfunction in the elderly increases the risk of cardiovascular and metabolic diseases. Even if thyroid-stimulating hormone (TSH) is within the normal range, brain atrophy and infarction-like vascular damage in elderly males will be aggravated with the increased TSH level. Iodine is an essential component of thyroid hormones. Iodine deficiency or excess may lead to a series of thyroid diseases. The risk threshold of iodine intake in the elderly is unknown. The goal of this observational study is to clarify the relationship between thyroid diseases and iodine intake in the elderly. The aims are:

1. to clarify the differences in the prevalence of thyroid diseases in the elderly with different iodine nutrition backgrounds.
2. to analyze the effects of mild iodine deficiency and iodine excess on the thyroid health of the elderly.
3. to explore the hazard threshold of iodine intake for old people.
4. to compare the differences in thyroid disease and iodine nutritional status between young and middle-aged people and old people.

Study Overview

• Status: Recruiting
• Conditions: Elderly; Nutrition, Healthy
• Intervention / Treatment: Other: Naturally different iodine levels exposure

Detailed Description

Part 1：A cross-sectional survey of thyroid diseases in adults in different iodine nutrition background areas.

Investigators will separately include adults ( middle-aged people and old people) in iodine-deficient, iodine-appropriate, and iodine-excessive areas. Venous blood will be collected to measure thyroid function and serum iodine. Thyroid volume and nodular disease were determined by B-ultrasonography. Drinking water, saliva and 24-h and spot urinary samples will be collected to precisely evaluate the daily iodine intake. Multiple indicators were used to accurately evaluate the iodine intake level of the subjects, and understand the differences in the prevalence of thyroid diseases in the elderly under different iodine nutrition backgrounds. Besides, the differences in thyroid disease and iodine nutritional status between young and middle-aged people and old people will be compared.

Part 2：A survey on the iodine nutrition status in the elderly with/without thyroid disease in iodine-appropriate areas.

Investigators will collect basic information (height, weight, age, other medical histories, etc.) and thyroid disease history information. Thyroid B-ultrasound and thyroid function tests were used to understand the current thyroid status of the elderly. The iodine dietary frequency questionnaire was used to assess the long-term iodine intake level of the survey subjects, and spot urinary iodine, 24-h urinary iodine and salivary iodine were used to assess the short-term iodine intake level of the survey subjects.

• Study Type: Observational
• Enrollment (Estimated): 1000

Contacts and Locations

• Study Contact: Name: Wenxing Guo, Doctor; Phone Number: (86)18822024500; Email: guowenxing@tmu.edu.cn
• Study Contact Backup: Name: Zhangzhao Wang, Doctor; Phone Number: (86)13821470215; Email: graik.wang@163.com

Study Locations

• China
  • Gansu
    • Lanzhou, Gansu, China, 730099
      • Recruiting
      • Gansu Provincial Center for Disease Control and Prevention
      • Contact: Yanling Wang
  • Shandong
    • Jinan, Shandong, China, 250014
      • Recruiting
      • Shandong provincial institute for endemic disease control
      • Contact: Xiaoming Wang
  • Tianjin
    • Tianjin, Tianjin, China, 300070
      • Active, not recruiting
      • Tianjin Medical University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

• Sampling Method: Probability Sample

Study Population

Elderly people with different levels of iodine exposure.

Description

Inclusion Criteria:

1. adults with at least 5 years of local residence;

Exclusion Criteria:

1. adults with family genetic diseases
2. adults with special dietary habits
3. adults taking iodine-containing drugs or supplements
4. adults with protein or nutritional deficiencies

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
thyroid function Indicators	Blood samples were collected to evaluate thyroid function.	2 years
thyroid volume	Thyroid volume was measured by B-ultrasound.	2 years
thyroid nodules	thyroid nodules were measured by B-ultrasound.	2 years
concentration of urinary iodine	The midstream urine samples were collected.	2 years
concentration of salivary iodine	The salivary samples were collected.	2 years
dietary iodine intake	Dietary iodine was measured by idine dietary frequency questionnaire.	2 years

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
free triiodothyronine (FT3)	thyroid function Indicators	2 years
free thyroxine (FT4)	thyroid function Indicators	2 years
thyroid-stimulating hormone (TSH)	thyroid function Indicators	2 years
thyroperoxidase antibody (TPOAb)	thyroid function Indicators	2 years
thyroglobulin antibody (TGAb)	thyroid function Indicators	2 years

Collaborators and Investigators

• Sponsor: Tianjin Medical University
• Collaborators: Tianjin Medical University General Hospital; Shandong Provincial Institute for Endemic Disease Control
• Investigators: Study Chair: Wenxing Guo, Doctor, Public Health School, Tianjin Medical University

Publications and helpful links

General Publications

• Leung AM, Braverman LE. Consequences of excess iodine. Nat Rev Endocrinol. 2014 Mar;10(3):136-42. doi: 10.1038/nrendo.2013.251. Epub 2013 Dec 17.
• Laurberg P, Cerqueira C, Ovesen L, Rasmussen LB, Perrild H, Andersen S, Pedersen IB, Carle A. Iodine intake as a determinant of thyroid disorders in populations. Best Pract Res Clin Endocrinol Metab. 2010 Feb;24(1):13-27. doi: 10.1016/j.beem.2009.08.013.
• Zimmermann MB, Boelaert K. Iodine deficiency and thyroid disorders. Lancet Diabetes Endocrinol. 2015 Apr;3(4):286-95. doi: 10.1016/S2213-8587(14)70225-6. Epub 2015 Jan 13.
• Li Y, Teng D, Ba J, Chen B, Du J, He L, Lai X, Teng X, Shi X, Li Y, Chi H, Liao E, Liu C, Liu L, Qin G, Qin Y, Quan H, Shi B, Sun H, Tang X, Tong N, Wang G, Zhang JA, Wang Y, Xue Y, Yan L, Yang J, Yang L, Yao Y, Ye Z, Zhang Q, Zhang L, Zhu J, Zhu M, Ning G, Mu Y, Zhao J, Shan Z, Teng W. Efficacy and Safety of Long-Term Universal Salt Iodization on Thyroid Disorders: Epidemiological Evidence from 31 Provinces of Mainland China. Thyroid. 2020 Apr;30(4):568-579. doi: 10.1089/thy.2019.0067. Epub 2020 Mar 24.
• Miller JC, MacDonell SO, Gray AR, Reid MR, Barr DJ, Thomson CD, Houghton LA. Iodine Status of New Zealand Elderly Residents in Long-Term Residential Care. Nutrients. 2016 Jul 23;8(8):445. doi: 10.3390/nu8080445.
• Limanova Z. Thyroid disease in the elderly. Vnitr Lek. 2018 Winter;64(11):993-1002.
• Zhai X, Zhang L, Chen L, Lian X, Liu C, Shi B, Shi L, Tong N, Wang S, Weng J, Zhao J, Teng X, Yu X, Lai Y, Wang W, Li C, Mao J, Li Y, Fan C, Li L, Shan Z, Teng W. An Age-Specific Serum Thyrotropin Reference Range for the Diagnosis of Thyroid Diseases in Older Adults: A Cross-Sectional Survey in China. Thyroid. 2018 Dec;28(12):1571-1579. doi: 10.1089/thy.2017.0715. Epub 2018 Nov 27.
• Barbesino G. Thyroid Function Changes in the Elderly and Their Relationship to Cardiovascular Health: A Mini-Review. Gerontology. 2019;65(1):1-8. doi: 10.1159/000490911. Epub 2018 Jul 20.
• Iacone R, Iaccarino Idelson P, Russo O, Donfrancesco C, Krogh V, Sieri S, Macchia PE, Formisano P, Lo Noce C, Palmieri L, Galeone D, Rendina D, Galletti F, Di Lenarda A, Giampaoli S, Strazzullo P, On Behalf Of The Minisal-Gircsi Study Group. Iodine Intake from Food and Iodized Salt as Related to Dietary Salt Consumption in the Italian Adult General Population. Nutrients. 2021 Sep 30;13(10):3486. doi: 10.3390/nu13103486.

Study record dates

Study Major Dates

• Study Start (Actual): February 17, 2023
• Primary Completion (Estimated): June 1, 2025
• Study Completion (Estimated): December 30, 2025

Study Registration Dates

• First Submitted: December 21, 2022
• First Submitted That Met QC Criteria: February 3, 2023
• First Posted (Actual): February 8, 2023

Study Record Updates

• Last Update Posted (Actual): August 16, 2023
• Last Update Submitted That Met QC Criteria: August 12, 2023
• Last Verified: August 1, 2023

More Information

Terms related to this study

• Keywords: adults; iodine; thyroid diseases
• Additional Relevant MeSH Terms: Endocrine System Diseases; Thyroid Diseases
• Other Study ID Numbers: NSFC-82204041

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: The data of the study are available from the project leader upon reasonable request.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No