Hypothyroidism in the elderly

Introduction to hypothyroidism in the elderly Hypothyroidism (hypothyroidism) refers to the deficiency of thyroid hormone caused by different causes, the metabolism of the body and the decline of various systemic functions of the body. The clinical syndrome caused by women is more common in men than in men, and with age. Increase, the prevalence rate is rising, due to changes in the autoimmune of the elderly, susceptible to immune disorders and other factors, so the elderly hypothyroidism is not uncommon, dysfunction begins in the old age or from the adult hypothyroidism to the elderly For the elderly, hypothyroidism. basic knowledge The proportion of sickness: 0.01% Susceptible people: the elderly Mode of infection: non-infectious Complications: systemic mucinous edema, coma, coronary heart disease, arrhythmia, heart failure, anemia, angina

The cause of hypothyroidism in the elderly

Thyroid (30%):

(1) Chronic thyroiditis.

(2) Graves' disease after 131I treatment or surgery.

(3) Subacute thyroiditis.

(4) Congenital hormonal production disorders.

(5) ectopic thyroid gland, lack of thyroid gland.

(6) lack of iodine, high iodine.

(7) Infiltration of cancer, amyloidosis, etc.

(8) Pregnancy, one-time sexual hypothyroidism after birth.

(9) Graves disease anti-thyroid preparation application process.

(10) Anti-thyroid substances.

Secondary hypothyroidism (20%):

(1) Secondary: TSH single deficiency, hypopituitarism.

(2) Three-dimensional: TRH single deficiency, hypothalamic hypofunction.

Peripheral hypothyroidism (20%):

Thyroid hormone refractory; anti-thyroid hormone antibody (T3, T4 receptor binding disorder and post-receptor defects).

Pathogenesis

Pathology

(1) The thyroid is divided into different causes:

1 Atrophic lesions: more common in chronic lymphocytic thyroiditis, etc., early glands have a large number of lymphocytes, plasma cell infiltration, long-term follicle destruction replaced by fibrous tissue, residual follicular epithelial cells are short, and the follicles in the follicles are significantly reduced After radiotherapy and surgery, the thyroid gland of the patient also showed obvious atrophy. The secondary hypothyroidism also had glandular shrinkage, follicular atrophy, and epithelial cells were flat, but the follicular cavity was filled with gelatin. In addition to follicular hypertrophy, it usually shows atrophic changes, even underdeveloped or absent.

2 goiter: goiter with unequal size nodules are common in endemic goiter, due to lack of iodine, chronic lymphocytic thyroiditis may also be accompanied by nodules; drug-induced, thyroid often generation Compensatory diffuse enlargement.

(2) pituitary: primary hypothyroidism due to TH reduction, feedback inhibition is weakened and TSH cells hypertrophy, long-term glandular pituitary enlargement, or adenoma, or accompanied by hyperprolactinemia, pituitary gland hypothyroidism patients With atrophy, lesions such as tumors or granuloma can be found.

(3) Others: skin keratinization, mucopolysaccharide deposition in the dermis, PAS or toluidine blue staining positive, formation of mucinous edema, deposition of the same substance between visceral cells, severe cases of serous effusion, skeletal muscle, smooth muscle Myocardium has interstitial edema, muscle lines disappear, muscle fibers are swollen and ruptured with vacuoles, brain cells atrophy, gliosis and focal metastasis, glomerular and tubular basement membrane thickening, endothelial and mesangial cells proliferate, Gastrointestinal mucosal atrophy and atherosclerosis.

2. Pathophysiology

Thyroid hormone deficiency affects all tissues of the body, so the symptoms are multifaceted. The most important pathophysiological changes caused by thyroid hormone deficiency are a large amount of extracellular mucinous substances in the interstitial space of the whole body. The substance is composed of acid mucopolysaccharide. a combination of (hyaluronic acid, chondroitin sulfate) and protein, a mucin that is highly hydrophilic, absorbs a large amount of water, deposits in the interstitial spaces of tissues, and is gradually expressed on the skin. Acidic mucopolysaccharide infiltrates and swells, keratinizes the surface of the skin, shrinks, and has a specific "mucinous edema" in the hair follicle and keratinized embolization of the sweat gland. The myocardial cells are contaminated by mucin and acid mucopolysaccharide, and interstitial edema. Myocardial tension is diminished, the heart is loose and enlarged, and it is a pseudo-hypertrophy of the heart muscle. In severe cases, myocardial fiber breaks, cell necrosis, pericardial effusion, large, cerebellum and hypothalamus can also have edema and degeneration, causing mental retardation, dementia, Nerve atrophy and decreased body temperature.

Elderly thyroid dysfunction prevention

Primary prevention

To prevent the risk factors and causes of hypothyroidism.

(1) Enhance people's self-care awareness to improve bad habits, pay attention to balanced diet, trace elements, drugs have an impact on the thyroid gland.

1 soil, well water, river water contains too much calcium, zinc, fluorine, organic sulfur complex, can cause goiter or strong anti-thyroid activity, some water sources are contaminated by bacteria, may cause goiter due to bacterial toxins.

2 drug effects: phenylbutazone, thiamine, sodium salicylate, potassium thiocyanate, thiouracil, tetracycline, colchicine, potassium perchlorate, nitrate, carbonic acid can inhibit thyroxine synthesis, resulting in Compensatory goiter, long-term medication can affect the intake of iodine and the release of thyroxine to cause goiter, such as some patients with asthma, long-term use of iodine-containing drugs to cause goiter, and even hypothyroidism.

3 food contains thyroid material, such as cruciferous radish, cabbage, rape, cabbage, coriander, cassava, water potato, soybean, walnut and other substances containing certain inhibition of thyroid synthesis, resulting in compensatory goiter For example, soy food can inhibit the reabsorption of thyroxine excreted via bile in the intestine, so that excessive thyroid hormone is excreted from the intestine. Cassava contains cyanocyanin, which easily forms thiocyanate after eating, which inhibits thyroid uptake. Iodine also inhibits the reabsorption of iodine by the renal tubules, which increases urinary iodine.

Although the food has been found to have different degrees of the above effects, the clinical simple food caused by hypothyroidism has not been reported.

(2) Prevent various infectious factors to prevent the initiation of autoimmune processes.

(3) Participate in the physical exercise to enhance physical fitness.

(4) If you find a similar situation, go to the hospital immediately.

2. Secondary prevention

The object is a hypothyroidism patient, the purpose is to prevent the occurrence of various complications of hypothyroidism, early diagnosis and reasonable treatment, so that the condition is stable.

Such as can prevent hypothyroidism, hypothyroidism, hypothyroidism caused by mental disorders.

3. Three levels of prevention

For patients who have had complications of hyperthyroidism, active treatment transforms the condition to a good condition, prevents heart failure, coma, etc., and reduces the mortality and disability rate caused by serious complications.

4. Risk factors and interventions

Hypothyroidism is divided into primary and secondary, and the causes are different.

(1) The primary hypothyroidism accounts for more than 90%. Some people think that it is mainly an autoimmune disease, which is caused by the disease of the thyroid gland. Most of them are the result of the destruction of acquired thyroid tissue. The cause can be:

1 Inflammation: Due to autoimmune reaction or viral infection, it is reported that about 80% of patients have anti-thyroid antibodies in their blood, and often complicated with rheumatism, leukoplakia and pernicious anemia. This disease can produce thyroid autoimmunity. Sexual atrophy or lymphocytic thyroiditis, leading to decreased thyroid function, which is the main cause of hypothyroidism in the elderly. Lymphocytic thyroiditis is an autoimmune disease, and its pathogenesis can be considered to be due to defects in innate immune surveillance. Conditions produce thyroid autoantibodies, form antigen-antibody complexes, activate K cells, and destroy thyroid cells encapsulated by this immune complex.

In addition, due to improper treatment of hyperthyroidism.

2 excessive thyroidectomy.

3131I treatment dose is too large, the main sequelae of 131I treatment is hypothyroidism, some are temporary, some are permanent, the latter can be divided into early onset hypothyroidism and late onset hypothyroidism, Concord Hospital on 211 cases After 10 years of follow-up, there were 5.2% of hypothyroidism, including 2.8% of early onset and 2.4% of late onset. After 131I treatment abroad, the incidence of hypothyroidism increased by 2% to 3% year by year, and up to 30% after 10 years. ~50%, which is related to the large dose of 131I in foreign countries.

4 anti-thyroid drugs used unreasonable (excess).

5 long-term application of amiodarone can also occur secondary hypothyroidism, but mostly temporary (reversible) hypothyroidism, some elderly people can also cause permanent hypothyroidism, a small number of high iodine areas can also occur goiter and hypothyroidism, according to It is easy to occur that the daily intake of iodide exceeds 6 mg.

6 iodine-deficient causes are more common in endemic goiter areas.

7 Many salts containing monovalent anions (such as SCW-, CLO4-, NO3-) and foods containing SCN-precursors can inhibit thyroid iodine, causing goiter and hypothyroidism.

8 hypothyroidism caused by genetic factors or gene mutations.

9 other, such as extensive metastases in the thyroid gland.

(2) secondary hypothyroidism: secondary hypothyroidism due to insufficient TSH caused by pituitary or hypothalamic diseases, often caused by tumor, surgery, radiotherapy or postpartum pituitary avascular necrosis, the anterior pituitary is extensively destroyed There is often a decrease in the secretion of complex pituitary hormones; individuals with unknown causes may be characterized by insufficient secretion of a single TSH, and insufficient secretion of TRH in the hypothalamus may reduce TSH and TH in succession, resulting in hypothyroidism, granuloma. Caused by chronic inflammation or radiation therapy.

5. Interventions

Maintain a good healthy body, normal immune status, prevent infections such as bacteria and viruses; use iodine-containing drugs and iodine supplements carefully; be appropriate for the treatment of hyperthyroidism, such as surgery 131I treatment; timely detection and treatment of pituitary and hypothalamic diseases, and Genetically related patients are waiting for gene repair treatment.

6. Community intervention

Through the in-depth work of professionals to prevent iodine deficiency and reasonable iodine supplementation, special attention should be paid to the effects of thyroid function when iodine-containing drugs must be used, effective preventive measures should be taken for some infectious factors; timely detection and treatment of hypothyroidism patients in the community To prevent the occurrence of serious complications.

Elderly thyroid dysfunction Complications, systemic mucinous edema, coma, coronary heart disease, arrhythmia, heart failure, anemia, angina

Often complicated by mucinous edema, coronary heart disease, arrhythmia, heart failure, and hypothyroidism or hypothyroidism caused by mental abnormalities.

Symptoms of hypothyroidism in the elderly Common symptoms Hypothyroidism, poor appetite, loss of appetite, anorexia, cortical dysfunction, pernicious anemia, block, rough skin, dullness, bradycardia

Many patients lack typical performance, and clinical manifestations are easily missed. For example, Bahemaka has diagnosed 46 cases of senile hypothyroidism in 2000 populations. In these 46 cases, only those diagnosed by clinical manifestations only accounted for 13%, 28% without hypothyroidism, and 22% with neuropsychiatric symptoms, Sawin reported, 95 out of 2139 were diagnosed with hypothyroidism, of which only 1 was based on routine practice. The case was diagnosed as a reduction in hypothyroidism in the elderly. After further in-depth examination of the medical history, 24% had hypothyroidism symptoms, which showed the difficulty of non-specific and clinical history of early hypothyroidism.

According to the severity of clinical manifestations, the following four stages are elaborated. These stages can also be understood as the continuous development of the disease.

1. Subclinical stage: that is, the initial stage of concealment, there is no clinical manifestation, the most important diagnosis based on this stage is the slight increase of TSH.

2. Clinical hypothyroidism stage: the severity and obviousness of clinical manifestations, depending on the onset and urgency of the onset, the speed and extent of hormone deficiency, and the relationship with the individual's response to thyroid hormone reduction, therefore Severe thyroid hormone deficiency sometimes clinical symptoms can be very mild, so the diagnosis of clinical hypothyroidism should have different degrees of clinical manifestations and increased serum TSH, T4 decreased, clinical hypothyroidism can be divided into light and heavy, the former symptoms Mild or atypical, showing only non-specific symptoms such as fatigue, lethargy, loss of appetite, and feeling of swelling around the body; while the latter is a mild manifestation of mucous edema.

3. The stage of mucinous edema: its manifestation is closely related to the cause. The primary hypothyroidism is insidious, and the course of disease is slow. It can be symptoms of mucus edema for more than 10 years, and secondary hypothyroidism. Need to be determined according to the disease, such as hyperthyroidism thyroid drug overdose, the cause is clear, the symptoms are mild, and soon after the treatment is corrected, the patient who started the disease due to surgery or 131I treatment, the onset is not very hidden, early symptoms from the 4th At the beginning of the week, typical symptoms are common after the 8th week.

(1) General performance: The earliest symptoms of mucinous edema are burnout, chills, slow speech, less sweat, lack of appetite, poor appetite, weight gain, body swelling, constipation, etc. The system's "mucus edema-like" typical performance: facial performance "indifferent", "stiff" or even "idiot", cheeks and eyelids swollen, lower eye pockets drooping, pale pale slightly sallow (caused by increased carotene) ), nose, lip thickening, large tongue and unclear pronunciation, low dumb, thin hair, dry and easy to fall off, ciliary, eyebrows falling off, rough and dry skin, non-depressible mucus edema, weight gain, mucinous edema A variety of organs and systems are involved.

(2) mental nervous system manifestations: memory loss, mental decline, slow response, lethargy, depression, sometimes worry and neurotic performance, severe cases develop into suspected schizophrenia, severe cases with dementia, fantasy, stupor, Drowsiness or convulsions, when the mucin deposition causes cerebellar dysfunction, ataxia, nystagmus and the like.

(3) Muscle and joint performance: muscle weakness and weakness, but also temporary muscle rigidity, paralysis, pain, etc., occasionally myasthenia gravis, chewing muscle, sternocleidomastoid muscle, quadriceps and hand muscles may appear Progressive muscular atrophy, a few cases of muscle hypertrophy, pseudomuscular hypertrophy at the distal extremities, local swelling can be caused when slamming muscles ("muscles" or "hill" phenomenon), relaxation after muscle contraction, loose after fist The systolic phase is normal or prolonged, but the flaccid phase is characteristically prolonged, often exceeding 350ms (normal 240-320ms), and the semi-relaxation time of Achilles tendon reflex is more obvious, which has important diagnostic value for this disease. Patients with mucinous edema may be associated with joint disease, occasional joint effusion, carcinogenesis in the carpal tunnel accumulates outside the nerve and carpal tunnel syndrome occurs, finger numbness, paresthesia.

(4) cardiovascular system performance: cardiac output decreased, bradycardia, often sinus, dilated heart sounds, heart sounds low blunt, ultrasound examination can be found in pericardial effusion, generally high proportion of serous exudate, at the same time There may be pleural or ascites effusion, long-term patients due to increased blood cholesterol, easy to develop coronary heart disease, but due to low metabolic rate, myocardial oxygen consumption decreased, angina and heart failure are rare, the diagnosis of hypothyroidism is hypothyroidism With one of the following exceptions:

1 heart is big.

2 arrhythmia.

3 heart failure.

4 ECG extensive ST-T changes or more than 1 degree atrioventricular block, and reduced or restored after hypothyroidism treatment, digestive system performance, slow gastrointestinal motility, gastric emptying disorder, gastric mucosal atrophy, gastric acid deficiency, half of patients Anti-parietal cell antibody positive, often anorexia, abdominal distension, constipation, severe cases may have paralytic ileus or mucous edema megacolon, due to lack of stomach acid or vitamin B12 malabsorption, can cause iron deficiency anemia or pernicious anemia.

5 endocrine system performance, loss of libido, male impotence, women often have menorrhagia, menstrual prolongation and infertility, about 1/3 of patients may have galactorrhea, or even increased saddle, affecting vision, primary hypothyroidism Autoimmune adrenal insufficiency and type 1 diabetes, known as Schmidt syndrome.

6 mucinous edema coma, seen in severe cases, induced by severe physical illness, interrupted TH replacement therapy, cold, infection, surgery and the use of anesthesia, sedatives, etc., clinical manifestations of drowsiness, low temperature (<35 ° C), slow breathing, Bradycardia, hypotension, hypoglycemia, hyponatremia, muscle relaxation in the limbs, reduced or disappeared reflexes, and even coma, shock, heart, kidney dysfunction and life-threatening.

Examination of hypothyroidism in the elderly

1. General inspection

Due to insufficient TH, affecting the synthesis of erythropoietin, bone marrow hematopoietic function can be reduced, can cause mild, moderate normal cell type normal pigmented anemia; due to more menstrual flow can cause small cell hypochromic anemia, a small number of gastric acid deficiency, lack of vitamin B12 Or folic acid can cause megaloblastic anemia, normal or low blood sugar, blood cholesterol, triglyceride often increased.

2. Thyroid function test

(1) serum TSH (sTSH or Utsh) is the earliest manifestation of primary hypothyroidism, such as elevated blood TSH and normal T4, T3, may be subclinical hypothyroidism, umbilical cord blood, neonatal blood or pregnancy Amniocentesis sTSH (or uTSH) at week 22 is helpful in the diagnosis of neonatal and fetal hypothyroidism.

(2) Blood TT4 (or FT4) decreases earlier than TT3 (or FT3).

(3) Blood TT3 (or FT3) decline is only seen in late or severe cases.

(4) As T4 is converted to T3 to compensate for hypothyroidism, blood rT3 is significantly reduced; amniotic fluid rT3 is decreased, which contributes to the prenatal diagnosis of congenital hypothyroidism.

(5) The rate of thyroid 131I decreased.

3. Examination of lesions

(1) Patients with primary hypothyroidism have elevated TSH, and hypothalamic-pituitary hypothyroidism is often reduced.

(2) TRH stimulation test, after intravenous injection of TRH400g, blood TSH does not increase suggestive of pituitary hypothyroidism, delayed elevation is hypothalamic hypothyroidism; if blood TSH base value has increased, TRH stimulation is higher, suggesting For primary hypothyroidism.

(3) blood T3, T4 increased, blood TSH (basic value or TRH excitement) normal or increased, no clinical manifestations of hyperthyroidism, or hypothyroidism patients with a larger dose of TH still no significant effect, suggesting that TH is not sensitive Less.

4. Imaging examination helps to determine the ectopic thyroid, hypothalamic-pituitary lesions.

5. Etiology check

According to the history, physical signs, experimental examinations and special examination results, the cause can be judged, such as TGAb, TPOAb increased, indicating that primary hypothyroidism is caused by autoimmune thyroid disease, potassium perchlorate excretion iodine test positive Diagnosis of congenital TH synthase deficiency.

Diagnosis and diagnosis of thyroid dysfunction in the elderly

In addition to clinical manifestations, it mainly relies on the detection of TT4, FT4, TT3, FT3, TSH and TRH stimulation tests to establish a diagnosis. Based on the confirmed hypothyroidism, the lesions are further identified according to the above examination, and the cause diagnosis is made as much as possible.

Effusion of the spleen with the growth of the saddle, hyperprolactinemia, should be excluded from pituitary tumors, especially prolactinoma, primary hypothyroidism after treatment, blood prolactin returned to normal, and pituitary tumors were ineffective.

Early mild hypothyroidism is more atypical, easily overlooked or misdiagnosed as anemia, idiopathic edema, nephrotic syndrome, glomerulonephritis, coronary heart disease, etc., the diagnosis should also rule out low T4 or T3 syndrome, the latter is common in Chronic liver and kidney disease with low plasma protein, such as suspected ectopic thyroid, or thyroid nodules, the nature of the neck mass is not known, may be considered by thyroid fine needle biopsy or thyroid imaging technology to identify.

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