Related Experiment Video
Updated: Jul 16, 2025
04:05
Author Spotlight: Accurately Assessing Thyroid Hormone-Driven Motor Alterations in Mouse
Published on: October 6, 2023
432
Biological variation in thyroid function tests in older adults and clinical implications.
Johannes Riis1,2, Louise Westergaard1,2, Jesper Karmisholt1,3
1Department of Clinical Medicine, Aalborg University, Aalborg, Denmark.
Clinical Endocrinology
|September 19, 2023
Summary
Thyroid function tests in older adults show reduced biological variation, especially for thyroxine (TT4). Measuring TT4 offers a reliable estimate of thyroid function, potentially improving clinical practice.
Area of Science:
- Endocrinology
- Gerontology
- Clinical Chemistry
Background:
- Interpreting thyroid function tests is complex due to biological variation, which increases with age.
- Age-related changes in thyrotropin (TSH) are known, but biological variation in older adults is not well understood.
Purpose of the Study:
- To investigate the biological variation of thyroid function tests in older adults.
- To compare thyroid hormone variation between older and younger adults.
Main Methods:
- Monthly blood sampling from 19 adults aged 65-99 over one year.
- Analysis of serum TSH, total thyroxine (TT4), and total triiodothyronine (TT3).
- Comparison with data from 15 younger euthyroid adults using similar methodology.
Main Results:
- Intraindividual variation (CVI) for TT4 and TT3 was significantly lower in older adults compared to younger adults.
- TT4 showed comparable CVI between individuals in older adults.
- Fewer samples were needed to determine the individual set-point for TT4 and TT3 in older adults.
Conclusions:
- Thyroxine (TT4) provides a reliable estimate of thyroid function in older adults due to lower biological variation.
- Reduced variation in TT4 and TT3 in older adults suggests potential for improved clinical interpretation.
- Measuring TT4 may enhance clinical practice for thyroid function assessment in the elderly.
Related Concept Videos
01:18Functions of Thyroid Hormones
2.8K
The thyroid hormone (TH) plays a pivotal role in the intricate orchestration of physiological processes, exerting profound effects on development, metabolism, and homeostasis throughout different life stages.
TH is indispensable for the normal development and maturation of the skeletal, muscular, and nervous systems during fetal and childhood growth. It facilitates bone mineral turnover and regulates protein synthesis in developing tissues, contributing significantly to overall growth and...
TH is indispensable for the normal development and maturation of the skeletal, muscular, and nervous systems during fetal and childhood growth. It facilitates bone mineral turnover and regulates protein synthesis in developing tissues, contributing significantly to overall growth and...
2.8K
01:20Synthesis and Regulation of Thyroid Hormones
4.7K
Low blood levels of the thyroid hormones — triiodothyronine (T3) and thyroxine (T4) — signal the hypothalamus to release the thyrotropin-releasing hormone (TRH). TRH then reaches the pituitary gland and stimulates the release of thyroid-stimulating hormone(TSH) into the bloodstream.
Upon reaching the thyroid gland, TSH stimulates the follicular cells' active uptake of iodide ions from the blood. The ions diffuse to the apical surface of the cells and are oxidized to iodine. The...
Upon reaching the thyroid gland, TSH stimulates the follicular cells' active uptake of iodide ions from the blood. The ions diffuse to the apical surface of the cells and are oxidized to iodine. The...
4.7K
01:29Bone Disorders
3.6K
Aging and its effect on bone remodeling is the most common cause of bone disorders. In young and healthy people, bone deposition and resorption happen at an equal rate to maintain optimal bone health.
Bone deposition is also affected by the levels of sex hormones like estrogen and testosterone that promote osteoblast activity and bone matrix synthesis. When the level of these hormones decreases due to aging, it causes a reduction in bone deposition. As a result, bone resorption by osteoclasts...
Bone deposition is also affected by the levels of sex hormones like estrogen and testosterone that promote osteoblast activity and bone matrix synthesis. When the level of these hormones decreases due to aging, it causes a reduction in bone deposition. As a result, bone resorption by osteoclasts...
3.6K
01:19The Effect of Aging on Tissues
2.1K
Several body functions deteriorate with age. The external signs of aging are easily identifiable. For example, the skin becomes dry, less elastic, and thins out, forming wrinkles. The skin of the face begins to appear looser due to a decrease in the levels of elastic and collagen fibers in the connective tissue. Additionally, melanin production in the hair follicle decreases with age, resulting in gray hair. Moreover, the senses of sight and hearing decline, so glasses and hearing aids may...
2.1K
01:23The Thyroid Gland
4.0K
The thyroid gland is a small, butterfly-shaped gland located in the neck and covers the anterior surface of the trachea. The gland has two lateral lobes connected by a thin tissue mass called the isthmus. Internally, each lobe comprises many small spherical structures known as thyroid follicles, surrounded by a network of blood vessels.
The follicles have a central cavity lined by simple cuboidal to squamous epithelial cells called follicular cells. These cells produce the glycoprotein...
The follicles have a central cavity lined by simple cuboidal to squamous epithelial cells called follicular cells. These cells produce the glycoprotein...
4.0K
01:19Factors Affecting Drug Biotransformation: Biological
177
Biological factors significantly impact drug metabolism, influencing drug clearance, efficacy, and potential toxicity.
Species differences: Variations in enzyme systems across species can cause disparities in drug metabolism. For instance, humans may metabolize certain drugs faster than rodents, altering therapeutic effects.
Strain differences: Genetic variations within a species can result in differing enzyme activity, impacting drug response and toxicity. For example, some mouse strains may...
Species differences: Variations in enzyme systems across species can cause disparities in drug metabolism. For instance, humans may metabolize certain drugs faster than rodents, altering therapeutic effects.
Strain differences: Genetic variations within a species can result in differing enzyme activity, impacting drug response and toxicity. For example, some mouse strains may...
177