Though the incidence of thyroid disease increases with age, the similarity of symptoms to aging means that they are diagnosed less frequently than they occur. Hair loss, fatigue or problems with memory and concentration do not seem so suspicious to us in an elderly person. And they should!

Contents:

  1. Aging thyroid - structural changes in the thyroid gland
  2. Aging thyroid - TSH, T3, and T4 levels in the elderly
  3. Aging thyroid - hypothyroidism in the elderly
  4. Aging thyroid gland - hyperthyroidism in the elderly
  5. Aging thyroid gland - neoplastic changes in the elderly
  6. Aging thyroid - what tests?
  7. Aging thyroid - development of the thyroid gland

The aging of the thyroid gland often does not have symptoms that are easily associated with hypothyroidism or hyperthyroidism in the elderly. Especially since thyroid hormone disorders in the elderly may be atypical in terms of clinical development. Subclinical forms of hypothyroidism or hyperthyroidism are common.

Meanwhile, we live longer and longer. And although we have access to modern technologies and drugs, we have to accept the fact that all cells of the body are aging. For this reason, eyesight deteriorates, joints ache sometimes, and memory fails more often. The aging thyroid gland sends out more subtle clinical signals that are easy to overlook, especially when, due to your old age, someone has other comorbidities and takes a lot of medications

Aging thyroid - structural changes in the thyroid gland

The lobes of the thyroid gland are divided into lobules, and these, in turn, into vesicles made of epithelial cells. C cells hide in the walls of the follicles or between them. With age, the follicular epithelium flattens and changes retrograde, thereby reducing the size of the thyroid follicles. Interestingly, the number of C cells is similar in men and women up to the age of 30, and in the following years it increases in men and decreases in women.

With age, the amount of glandular tissue in the thyroid gland decreases, while fibrous tissue and lymphatic elements (infiltrates) increase, and nodules may appear. They are detected in ultrasound in 50% of patients over 60 years of age. Italian scientists have shown thyroid nodules in nearly 75% of women aged 55-74,living in iodine deficient areas.

Aging thyroid - TSH, T3, and T4 levels in the elderly

In the elderly, the daily T4 production in the thyroid gland decreases by about 20 µg. On the other hand, T3 is reduced by about 20 µg in men and by about 10 µg in women. Only a fraction of T3 (around 20%) is released directly from the thyroid gland, most of it is produced by the conversion of T4 in the liver, kidneys, brain, and skeletal muscle.

Prolonged malnutrition or severe diseases (e.g. myocardial infarction or infections) inhibit peripheral T4 conversion, lowering T3 levels. Some medications, often taken by elderly people, have a similar effect, e.g. propranolol, amiodarone, glucocorticoids and iodine-based contrast agents.

The level of thyrotropin (TSH) in the blood serum of old people was the subject of numerous studies. TSH, or thyrotropin, is a hormone produced by the anterior pituitary gland, but its level is an indicator of how the thyroid functions. It seems that there are no significant physiological changes in TSH levels related to age, its level is modified, but usually the result is normal, ie in the range of 0.4-4.3 µIU / ml. One of the studies showed that in the group between 18 and 24 years of age the average TSH concentration is 1.47 mIU / l, and in people over eighty - 1.07 mIU / l.

In older age, however, the availability of iodine decreases. With age, the thyroid gland captures less and less iodine (provided with food and drink). In people between 80 and 90 years of age this gland capacity is about 40% lower than that of 30-year-olds. Fortunately, natural hormone reserves are usually sufficient to keep the thyroid gland working properly.

Aging thyroid - hypothyroidism in the elderly

The incidence of hypothyroidism increases with age. It occurs about 5 times more often in women than in men, it is found in 1-6% of people up to the age of 60.

The main cause of hypothyroidism is chronic lymphocytic inflammation of this gland, i.e. Hashimoto's disease. Even 20-30% of women over 80 have it. (data vary by region, iodine intake is important). An important cause of thyroid insufficiency and hormone deficiency is also treatment related to other diseases, e.g.

  • radioiodine therapy,
  • radiotherapy of head and chest neoplasms,
  • administration of lithium s alt or interferon,
  • taking antitussives and antiseptics based on iodine compounds.

In elderly people it is recommended, especially initially, to uselower doses of thyroid hormones, which is the result of reduced demand and increased tissue sensitivity to these hormones, but after 6-8 weeks the tests should be repeated and the dose verified.

Due to the decrease in the rate of metabolic processes with age, the final dose of levothyroxine is usually about 40% lower than in young people. It sometimes happens that the dose is properly selected, but at the same time, drugs that inhibit the absorption of the hormone are used.

Many of the symptoms of hypothyroidism are the same as aging. This is e.g.

  • memory impairment
  • apathy
  • psychophysical slowdown
  • dry skin
  • cold intolerance
  • constipation
  • hair loss.

For this reason, patients often do not even know that their thyroid is not functioning properly. In the long run, this can have a negative effect on the body, such as:

  • slow heart rate
  • increasing the risk of atherosclerosis
  • arterial stiffness.

According to some experts, the possible presence of hypothyroidism in old age is very likely due to coexistence in the same person

  • hypercholesterolemia
  • macrocytic (megaloblastic anemia, where the maturation of blood cells is disturbed)
  • constipation
  • features of congestive heart failure.

Aging thyroid gland - hyperthyroidism in the elderly

The incidence of hyperthyroidism (hyperthyroidism) is higher in women than in men, especially after the age of 70

The cause of the disease (more often than in young people)

  • multinodular goiter
  • single thyroid tumor
  • Graves' disease.
  • Occasionally the cause of hyperthyroidism may be thyroid cancer or excessive secretion of TSH by the pituitary adenoma.
  • Often hyperthyroidism in older age groups develops as a result of administering too high doses of levothyroxine in the treatment of hypothyroidism or neutral goiter therapy.

And in this case it is easy to overlook the symptoms of the disease, because they are less severe. Heat intolerance, muscle tremors or increased nervous excitability are much less common than in young people with hyperthyroidism. On the other hand, it can manifest itself with symptoms from the digestive system (diarrhea, vomiting) or nervous system (depression, manic states, dementia).

Hyperthyroidism should always be suspected and ruled out in the case of worsening dementia disorders, aggressive behavior,hallucinations. In the elderly, hyperthyroidism has a particularly negative effect on the central nervous system. In people over 55 years of age with lowered TSH levels, a 2-3-fold increase in the risk of Alzheimer's disease has been shown, and in people between 60 and 90 years of age, with an increased concentration of FT4 - an increased risk of brain atrophy in the region hippocampus and amygdala.

In the elderly, hyperthyroidism increases the risk of osteoporosis and fractures.

The relationship between hyperthyroidism and atrial fibrillation is best documented. It is present in 20-35% of elderly patients with hyperthyroidism, with the risk being especially high in cases of hyperthyroidism due to nodular changes.

Aging thyroid gland - neoplastic changes in the elderly

Many people over 50 has benign changes in the thyroid gland that do not require further diagnosis and treatment. Poland is one of the countries with a low incidence of thyroid cancer. Women get sick more often.

The risk of getting sick also increases with age. Please note that it is greater especially in the case of:

  • positive history of radiotherapy (head, neck, whole body),
  • previous history of thyroid cancer in the family,
  • presence of a hard tumor that cannot be moved against the substrate,
  • hoarseness,
  • difficulty swallowing,
  • lymph node enlargement
  • any changes that suspect malignancy on ultrasound.

Fine-needle biopsy is the basic test that enables the differentiation of benign lesions from thyroid neoplasms. In people over 40 years of age Thyroid cancer, especially if differentiated, is more aggressive, has a greater tendency to spread beyond the thyroid gland and form distant metastases. Fortunately, the detection rate of this type of cancer is increasing and therefore treatment can be started at an early stage.

Aging thyroid - what tests?

Thyroid diseases are currently a problem of 30-40% of Poles. When this gland is sick, it does not hurt and usually does not make itself felt for a long time. But the effects of disturbances in his work affect the entire body.

Everyone should check their TSH levels once in a while, ideally every 12 months, to check that their thyroid is in good condition and that there is nothing wrong with it.

In the case of hyperfunction of the gland, the TSH level is low (below 0.1 µIU / ml), in the case of hypothyroidism - high (above 4.3 µIU / ml). Free hormones, i.e. fT3 and fT4, are also determined from the blood serum. In the diagnosis of autoimmune thyroid diseases (including Hashimoto's and Graves' diseases),anti-thyroid peroxidase (anti-TPO) antibodies, anti-thyroglobulin (anti-TG) antibodies and anti-TSH receptor antibodies - hTRAb.

Ultrasound examination detects even 2-millimeter lesions, but it does not make it possible to determine whether they are benign or malignant. If the ultrasound shows significant enlargement of the thyroid gland, your doctor may order a chest X-ray to see if the gland grows inward and forms a retrosternal goiter. This test also provides information whether the goiter compresses the trachea and esophagus.

Aging thyroid - development of the thyroid gland

Thyroid development begins in the 4th week of pregnancy. It wanders around the 7th week to reach its final position - on the front surface of the trachea. It is made of two lobes connected by a narrow strait (knot). Sometimes there is also a third lobe - the pyramidal one. The volume of the thyroid gland under physiological conditions does not exceed 18 ml in women and 25 ml in men.

The thyroid gland may enlarge during pregnancy, and its size also varies depending on the phase of a woman's monthly cycle. It should feel soft to the touch and its surface should be smooth.

The thyroid gland produces the following hormones from iodine and amino acids: triiodothyronine (T3) and thyroxine (T4). They are essential for the development and work of the central nervous system, heart and reproductive system. Hormones produced by the thyroid are responsible for proper metabolism, a slim figure, good mood, skin and hair. There are also cells in the thyroid that produce calcitonin.

Problem: thyroid and women's matters

Disorders of the thyroid gland have a huge impact on the reproductive system. Her hyperfunction may accelerate puberty and cause the first menstruation to appear early, even in the age of 9 years. In later years, it can cause scanty bleeding or even amenorrhea.

Hypothyroidism can delay puberty and stop growth. It can cause heavy periods, even leading to anemia. It promotes the development of polycystic ovary syndrome, which results in anovulation and impeded implantation of a fertilized egg in the uterus. In women who are pregnant, it increases the risk of miscarriage, premature birth, birth defects or the mental retardation of the baby.

About the authorJoanna Karwat A journalist specializing in he alth matters. For over 25 years, she has been following trends in medicine and meets doctors to talk about new treatments. She received two distinctions in the "Medical Journalist of the Year 2022" competition in the press journalism category. He spends every free moment playing volleyball. She won gold inJournalists' Championship in Beach Volleyball in 2016.

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Category:

Geriatrics