Clinical trial NCT06218043: An Iodine Balance Study to Investigate the Recommended Iodine Intake in an Elderly Population
Official title: An Iodine Balance Study in the Elderly
Study type: INTERVENTIONAL
Overall status: RECRUITING
Phase: NA
Conditions: Nutrition, Healthy
Keywords: recommended intake of iodine
iodine balance study
thyroid diseases
elderly
Lead sponsor: Tianjin Medical University
Sponsor class: OTHER
Collaborators: name: Tianjin Medical University General Hospital
name: Gansu Provincial Centre for Disease Control and Prevention
First posted: 2024-01-23
Enrollment: 30
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: NA
Intervention model: SEQUENTIAL
Intervention model description: When the first phase of the iodine balance study without intervention is completed. After an interval of 4 days, subjects who eat iodized salt will be included, the iodized salt will be replaced with non-iodized salt, and the second phase of the iodine balance experiment will begin.
Primary purpose: HEALTH_SERVICES_RESEARCH

Brief summary: Current Chinese dietary iodine reference intake (DRIs) standards lack direct data on recommended iodine intake (RNI) in the elderly. The elderly have a high prevalence of thyroid diseases. The risk threshold of iodine intake in the elderly is unknown. Identifying the appropriate iodine intake for the elderly to maintain optimal thyroid function to reduce the burden on medical resources is a public health issue requiring high attention. The iodine balance study is an important method for exploring physiological iodine requirements. Few iodine balance studies have been conducted in the elderly. This study aimed to conduct an iodine balance study and provide information on the appropriate iodine intake level for elderly people.

Detailed description: The investigators measured subjects' food and water intake throughout the day using weighing methods, and collected all urine and fecal samples. Food, drinking water, fecal and urine samples were taken to determine iodine concentrations. Each subject was required to participate in two phases of iodine balance studies. Each stage lasts 4 to 10 days. There was no intervention in the first half of the experiment, and there was an intervention of iodized salt/non-iodized salt consumption in the second half of the experiment. The appropriate level of iodine intake for the elderly was explored by fitting and analyzing the dose change relationship between iodine intake and iodine excretion.

Eligibility criteria: The target population of this study is elderly people over 60 years old. Adults living in the same household can also participate.

Inclusion Criteria:

1. aged 18 and above;
2. at least 5 years of local residence.

Exclusion Criteria:

1. family genetic diseases；
2. special dietary habits；
3. taking iodine-containing drugs or supplements；
4. metabolic diseases;
5. thyroid diseases.

Primary outcomes:
measure: Iodine intake
timeFrame: Each phase of the iodine balance study lasts 4 to 10 days.
measure: Iodine excretion
timeFrame: Each phase of the iodine balance study lasts 4 to 10 days.
Secondary outcomes:
measure: thyroid function indexes
timeFrame: Within one week before the start of the experiment.
measure: thyroid volumn
timeFrame: Within one week before the start of the experiment.
measure: salivary iodine
timeFrame: 4 to 10 days
measure: blood pressure
timeFrame: Within one week before the start of the experiment.
measure: fasting blood glucose
timeFrame: Within one week before the start of the experiment.
Other outcomes:
Locations:
city: Lanzhou
country: China
facility: Gansu provincial center for disease control and prevention
state: Gansu
city: Jinan
country: China
facility: Shandong provincial institute for endemic disease control
state: Shandong
city: Tianjin
country: China
facility: Tianjin Medical University
state: Tianjin
Study officials:
affiliation: Department of Nutrition and Food Hygiene, School of Public Health, Tianjin Medical University
name: Wenxing Guo
role: STUDY_CHAIR
References:
citation: 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.
citation: Farebrother J, Zimmermann MB, Andersson M. Excess iodine intake: sources, assessment, and effects on thyroid function. Ann N Y Acad Sci. 2019 Jun;1446(1):44-65. doi: 10.1111/nyas.14041. Epub 2019 Mar 20.
citation: Dold S, Zimmermann MB, Baumgartner J, Davaz T, Galetti V, Braegger C, Andersson M. A dose-response crossover iodine balance study to determine iodine requirements in early infancy. Am J Clin Nutr. 2016 Sep;104(3):620-8. doi: 10.3945/ajcn.116.134049. Epub 2016 Jul 27.
citation: Malvaux P, Beckers C, De Visscher M. Iodine balance studies in nongoitrous children and in adolescents on low iodine intake. J Clin Endocrinol Metab. 1969 Jan;29(1):79-84. doi: 10.1210/jcem-29-1-79. No abstract available.
citation: Ingenbleek Y, Malvaux P. Iodine balance studies in protein-calorie malnutrition. Arch Dis Child. 1974 Apr;49(4):305-9. doi: 10.1136/adc.49.4.305.
citation: Chinese Nutrition Society. Chinese Dietary Reference Intakes. Beijing, People's Medical Publishing House. 2014: 230-237. Chinese.
citation: Yang L, Wang J, Yang J, Zhang H, Liu X, Mao D, Lu J, Gu Y, Li X, Wang H, Xu J, Tan H, Zhang H, Yu W, Tao X, Fan Y, Cai Q, Liu X, Yang X. An iodine balance study to explore the recommended nutrient intake of iodine in Chinese young adults. Br J Nutr. 2020 Dec 14;124(11):1156-1165. doi: 10.1017/S0007114520002196. Epub 2020 Jun 22.
citation: Tan L, Tian X, Wang W, Guo X, Sang Z, Li X, Zhang P, Sun Y, Tang C, Xu Z, Shen J, Zhang W. Exploration of the appropriate recommended nutrient intake of iodine in healthy Chinese women: an iodine balance experiment. Br J Nutr. 2019 Mar 14;121(5):519-528. doi: 10.1017/S0007114518003653. Epub 2018 Dec 11.