-
Swiss Medical Weekly 2014Subclinical hypothyroidism, which is defined as elevated thyroid-stimulating hormone (TSH) levels with free thyroxine concentrations within the reference range, is a... (Review)
Review
Subclinical hypothyroidism, which is defined as elevated thyroid-stimulating hormone (TSH) levels with free thyroxine concentrations within the reference range, is a common disorder that increases with age and affects up to 18% of the elderly, with a higher prevalence in women compared to men. Prospective data have shown an increased risk of coronary heart disease events, heart failure, and cardiovascular mortality among affected adults. Conflicting results have been found on the association between subclinical hypothyroidism and cognitive impairment, depression and the risk of fractures. Management strategies including screening and treatment of subclinical hypothyroidism are still controversial, while the ongoing European randomised controlled trial "TRUST" targets to solve these uncertainties. This narrative review aims to assess current evidence on the clinical aspects, as well as screening and treatment recommendations in adults with subclinical hypothyroidism.
Topics: Asymptomatic Diseases; Cardiovascular Diseases; Female; Humans; Hypothyroidism; Male; Mental Disorders; Muscular Diseases; Thyrotropin; Thyroxine
PubMed: 25536449
DOI: 10.4414/smw.2014.14058 -
Scientific Reports Mar 2022This is a retrospective longitudinal study that uses data from the National Health Insurance Research Database (NHIRD) of Taiwan of which hypothyroid patients who...
This is a retrospective longitudinal study that uses data from the National Health Insurance Research Database (NHIRD) of Taiwan of which hypothyroid patients who received a diagnosis between 2000 and 2010 were selected and followed up until 2011. The primary outcome of this study was the occurrence of tinnitus (ICD-9-CM code 388.3). The relevant comorbidities were selected as potential confounders according to the literature, which included vertigo (ICD-9-CM code 386), insomnia (ICD-9-CM code 780), anxiety (ICD-9-CM code 300.00), and hearing loss (ICD-9-CM code 388-389). The overall incidence of tinnitus was significantly higher in the hypothyroidism cohort than in the non-hypothyroidism cohort (9.49 vs. 6.03 per 1000 person-years), with an adjusted HR of 1.35 (95% CI 1.18-1.54) after adjusting potential confounders. The incidences of tinnitus, as stratified by gender, age, comorbidity, and follow-up time, were all significantly higher in the hypothyroidism cohort than those in the non-hypothyroidism cohort. The incidence of tinnitus significantly increased with age (aHR = 1.01, 95% CI 1.01-1.02). In conclusion, we report the relationship between hypothyroidism and the increased risk for tinnitus. We also found that hypothyroidism patients are at increased risk of developing tinnitus when associated with comorbidities including vertigo, hearing loss, and insomnia.
Topics: Comorbidity; Hearing Loss; Humans; Hypothyroidism; Incidence; Longitudinal Studies; Retrospective Studies; Risk Factors; Sleep Initiation and Maintenance Disorders; Taiwan; Tinnitus; Vertigo
PubMed: 35233053
DOI: 10.1038/s41598-022-07457-0 -
International Journal of Molecular... Nov 2022The primary functional units of the thyroid gland are follicles of various sizes comprised of a monolayer of epithelial cells (thyrocytes) surrounding an apical... (Review)
Review
The primary functional units of the thyroid gland are follicles of various sizes comprised of a monolayer of epithelial cells (thyrocytes) surrounding an apical extracellular cavity known as the follicle lumen. In the normal thyroid gland, the follicle lumen is filled with secreted protein (referred to as colloid), comprised nearly exclusively of thyroglobulin with a half-life ranging from days to weeks. At the cellular boundary of the follicle lumen, secreted thyroglobulin becomes iodinated, resulting from the coordinated activities of enzymes localized to the thyrocyte apical plasma membrane. Thyroglobulin appearance in evolution is essentially synchronous with the appearance of the follicular architecture of the vertebrate thyroid gland. Thyroglobulin is the most highly expressed thyroid gene and represents the most abundantly expressed thyroid protein. Wildtype thyroglobulin protein is a large and complex glycoprotein that folds in the endoplasmic reticulum, leading to homodimerization and export via the classical secretory pathway to the follicle lumen. However, of the hundreds of human thyroglobulin genetic variants, most exhibit increased susceptibility to misfolding with defective export from the endoplasmic reticulum, triggering hypothyroidism as well as thyroidal endoplasmic reticulum stress. The human disease of hypothyroidism with defective thyroglobulin (either homozygous, or compound heterozygous) can be experimentally modeled in thyrocyte cell culture, or in whole animals, such as mice that are readily amenable to genetic manipulation. From a combination of approaches, it can be demonstrated that in the setting of thyroglobulin misfolding, thyrocytes under chronic continuous ER stress exhibit increased susceptibility to cell death, with interesting cell biological and pathophysiological consequences.
Topics: Mice; Humans; Animals; Thyroglobulin; Hypothyroidism; Thyroid Epithelial Cells; Endoplasmic Reticulum; Proteins
PubMed: 36362390
DOI: 10.3390/ijms232113605 -
European Journal of Pediatrics Jul 2021Screening for hypo- or hyperthyroidism in adults is generally done by measuring the serum thyrotropin (thyroid-stimulating hormone, TSH) concentration. This is an... (Review)
Review
Screening for hypo- or hyperthyroidism in adults is generally done by measuring the serum thyrotropin (thyroid-stimulating hormone, TSH) concentration. This is an efficient approach in case of suspected acquired thyroid disease. However, in infants and children, congenital hypothalamus-pituitary-thyroid (HPT) axis disorders also need to be considered, including primary and central congenital hypothyroidism, and even rarer thyroid hormone receptor and transporter defects. In primary congenital hypothyroidism, TSH will be elevated, but in the other congenital HPT axis disorders, TSH is usually within the normal range. Free thyroxine (FT4) assessment is essential for the diagnosis in these conditions.Conclusion: Here we discuss a number of rare congenital HPT axis disorders in which TSH is normal, but FT4 is low, and provide a clinical algorithm to distinguish between these disorders. What is Known: • A single thyroid-stimulating hormone (TSH) measurement is an appropriate screening method for primary hypothyroidism. • For central hypothyroidism and rare thyroid hormone receptor and transporter defects a free thyroxine (FT4) measurement is essential for the diagnosis because TSH is usually normal. What is New: • Here we present a new problem-oriented clinical algorithm including a diagnostic flow-chart for low FT4 and normal TSH in infants and children.
Topics: Adult; Child; Congenital Hypothyroidism; Humans; Infant; Thyroid Diseases; Thyroid Function Tests; Thyrotropin; Thyroxine
PubMed: 33585976
DOI: 10.1007/s00431-021-03976-6 -
International Journal of Clinical... Jul 2015Accurate diagnosis and treatment of subclinical hypothyroidism (SCH) is challenging in clinical practice because of differing upper limits of normal (ULN) for... (Review)
Review
BACKGROUND AND AIMS
Accurate diagnosis and treatment of subclinical hypothyroidism (SCH) is challenging in clinical practice because of differing upper limits of normal (ULN) for thyroid-stimulating hormone (TSH). This review summarises the various definitions of SCH and their impact on reported SCH prevalence.
METHODOLOGY
Articles reporting the prevalence of SCH in relation to the ULN of TSH in human studies were identified through an English-language PubMed search for 'subclinical hypothyroidism,' 'prevalence,' and 'TSH' within the title and/or abstract. Relevant articles and related literature were selected for inclusion.
RESULTS
Estimates for the prevalence of SCH varied by sex, age, race/ethnicity, and geographic location (range, 0.4-16.9%). Higher rates of SCH were consistently reported in women (0.9-16.9%) and older individuals (2.7-16.9%). However, the ULN of TSH in those considered free of thyroid disease and not at risk increased progressively with age, suggesting that reports of SCH prevalence in elderly people may be overestimated. Multiple studies reported an increased risk of progression to overt hypothyroidism among individuals with elevated TSH and antithyroid antibodies.
CONCLUSIONS
Given the variable definition of SCH based on an inconsistent ULN for TSH, it is currently difficult to ascertain the true prevalence of SCH and to correctly label and treat patients with SCH; use of age-adjusted definitions may be considered when assessing prevalence. A diagnosis of SCH does not necessarily merit treatment, especially if TSH elevations are transient (i.e. not persistent for > 3-6 months) and the patient lacks other risk factors for developing overt hypothyroidism.
Topics: Diagnosis, Differential; Disease Progression; Global Health; Humans; Hypothyroidism; Prevalence; Reproducibility of Results; Thyrotropin
PubMed: 25846327
DOI: 10.1111/ijcp.12619 -
Medicina Oral, Patologia Oral Y Cirugia... Jan 2023Burning mouth syndrome is an idiopathic condition characterized by burning pain in a normal-appearing oral mucosa lasting at least four to six months. In the case of... (Review)
Review
BACKGROUND
Burning mouth syndrome is an idiopathic condition characterized by burning pain in a normal-appearing oral mucosa lasting at least four to six months. In the case of secondary burning mouth syndrome is associated with local or systemic factors (such as thyroid disorders) that can cause these symptoms. The aim of this review was to study the relationship between thyroid disorders and burning mouth syndrome.
MATERIAL AND METHODS
The present study followed the PRISMA guidelines. An electronic search strategy was developed for PubMed/Medline, Scopus and Cochrane. The following combination of keywords and Boolean operators were used: Thyroid AND burning mouth; Thyroid AND burning mouth syndrome; Hypothyroidism AND burning mouth; Hypothyroidism AND burning mouth syndrome; Hyperthyroidism AND burning mouth; Hyperthyroidism AND burning mouth syndrome. The results were processed by existing free software in https://www.graphpad.com/. To evaluate the association of the categorical variables we used the Fisher test at a level of significance of p-value ≤ 0,05. As a primary summary measure the Odds Ratio (OR) has been used. To analyze the risk of bias the guidelines of the GRADE guide were used and the grade of evidence was analyzed by the guide of Joanna Briggs Institute: Levels of Evidence and Grades of Recommendations.
RESULTS
After applying the inclusion and exclusion criteria, 5 studies were selected for review. The Chi-square was 10.92 and the Odds Ratio was 3.31 with respect to TSH values with p <0.0001 (Fisher's test). The population of patients with TSH alterations is increased in 80.49% and decreased in 19.51%.
CONCLUSIONS
It can be concluded that thyroid hormone abnormalities are a factor in secondary burning mouth syndrome; specially in patients with hypothyroidism.
Topics: Humans; Burning Mouth Syndrome; Hypothyroidism; Thyroid Hormones; Hyperthyroidism; Thyrotropin
PubMed: 36173716
DOI: 10.4317/medoral.25596 -
Revista de Neurologia Jul 2022Headache and hypothyroidism are common comorbidities. This is a cross-sectional study of the prevalence of hypothyroidism in headache patients in the largest Mexican...
INTRODUCTION
Headache and hypothyroidism are common comorbidities. This is a cross-sectional study of the prevalence of hypothyroidism in headache patients in the largest Mexican headache registry.
PATIENTS AND METHODS
PREMECEF is an e-database for patients with headaches. Data was recollected from July 2017-April 2019 in three centers of Monterrey, Mexico.
RESULTS
Of 869 patients, 35 (4%) had hypothyroidism. Four had two different headache diagnoses; of the 39 individual diagnoses, 23 were primary, 1 secondary, 13 cranial neuralgias, and 2 unspecified headaches. Hypothyroidism prevalence: 8.3% in unspecified, 6.5% in cranial neuralgias, 3.4% in primary, and 1.9% in secondary headaches; in tension-type headache (TTH) was 3.9%, in migraines 3.2%, in trigeminal neuralgia 6.1%, and in occipital neuralgia 6.3%.
CONCLUSION
This is the first report on the prevalence of hypothyroidism in occipital and trigeminal neuralgia. The prevalence of hypothyroidism in migraine and TTH is higher than the general population.
Topics: Comorbidity; Cranial Nerve Diseases; Cross-Sectional Studies; Headache; Humans; Hypothyroidism; Mexico; Migraine Disorders; Neuralgia; Tension-Type Headache; Trigeminal Neuralgia
PubMed: 35765824
DOI: 10.33588/rn.7501.2022054 -
The Journal of Endocrinology Dec 2015Central congenital hypothyroidism (CCH) may occur in isolation, or more frequently in combination with additional pituitary hormone deficits with or without associated... (Review)
Review
Central congenital hypothyroidism (CCH) may occur in isolation, or more frequently in combination with additional pituitary hormone deficits with or without associated extrapituitary abnormalities. Although uncommon, it may be more prevalent than previously thought, affecting up to 1:16 000 neonates in the Netherlands. Since TSH is not elevated, CCH will evade diagnosis in primary, TSH-based, CH screening programs and delayed detection may result in neurodevelopmental delay due to untreated neonatal hypothyroidism. Alternatively, coexisting growth hormones or ACTH deficiency may pose additional risks, such as life threatening hypoglycaemia. Genetic ascertainment is possible in a minority of cases and reveals mutations in genes controlling the TSH biosynthetic pathway (TSHB, TRHR, IGSF1) in isolated TSH deficiency, or early (HESX1, LHX3, LHX4, SOX3, OTX2) or late (PROP1, POU1F1) pituitary transcription factors in combined hormone deficits. Since TSH cannot be used as an indicator of euthyroidism, adequacy of treatment can be difficult to monitor due to a paucity of alternative biomarkers. This review will summarize the normal physiology of pituitary development and the hypothalamic-pituitary-thyroid axis, then describe known genetic causes of isolated central hypothyroidism and combined pituitary hormone deficits associated with TSH deficiency. Difficulties in diagnosis and management of these conditions will then be discussed.
Topics: Congenital Hypothyroidism; Humans; Infant, Newborn; Pituitary Gland; Pituitary Hormones
PubMed: 26416826
DOI: 10.1530/JOE-15-0341 -
Frontiers in Endocrinology 2022Congenital hypothyroidism diagnosed by TSH assessment in bloodspot screening may be overlooked in preterm newborns due to immaturity of the...
Congenital hypothyroidism diagnosed by TSH assessment in bloodspot screening may be overlooked in preterm newborns due to immaturity of the hypothalamus-pituitary-thyroid axis in them. The purpose of the study was to determine the prevalence and causes of hypothyroxinemia in preterm newborns, determined by TSH and FT4 serum concentration measurement, performed on the 3-5 day of life. We assessed TSH, FT4 and FT3 serum concentration on the 3-5 day of life in preterm children born at our centre within three consecutive years. We assessed the incidence of hypothyroxinemia, and its cause: primary hypothyroidism, secondary hypothyroidism or low FT4 syndrome - with normal TSH concentration, its dependence - among others - on gestational age (GA), birth body weight (BBW) and being SGA. A total of 525 preterm children were examined. FT4 concentration was decreased in 14.9% of preterm newborns. The most frequent cause of hypothyroxinemia was low FT4 syndrome (79.5%). More than 92% cases of hypothyroxinemia occurred in children born before the 32 week and/or with BBW below 1500 g. Thus, every fourth child in these groups had a reduced FT4 concentration. Neonates with hypothyroxinemia were significantly lighter than those with normal FT4. In older and heavier neonates with hypothyroxinemia, serious congenital defects were observed. Neither IVH nor SGA nor twin pregnancies predispose children to hypothyroxinemia. Among newborns with untreated hypothyroxinemia in whom TSH and FT4 assessment was repeated within 2-5 weeks, a decreased FT4 concentration was confirmed in 56.1% of cases. As hypothyroxinemia affects 25% of newborns born before the 32 week of gestation and those in whom BBW is less than 1500g, it seems that in this group of children the newborn screening should be extended to measure serum TSH and FT4 concentration between the 3-5 day of life. In older and heavier neonates, additional serum TSH and FT4 assessment should be limited to children with severe congenital abnormalities but not to all SGA or twins. Despite the fact that the most common form of preterm hypothyroxinemia is low FT4 syndrome, it should be emphasized that FT4 remains lowered on subsequent testing in more them 50% of cases.
Topics: Aged; Birth Weight; Child; Congenital Hypothyroidism; Female; Gestational Age; Humans; Infant, Newborn; Pregnancy; Pregnancy Complications; Prevalence; Thyrotropin
PubMed: 36034431
DOI: 10.3389/fendo.2022.940152 -
Clinical Endocrinology Jun 2016The management of primary hypothyroidism with levothyroxine (L-T4) is simple, effective and safe, and most patients report improved well-being on initiation of... (Review)
Review
The management of primary hypothyroidism with levothyroxine (L-T4) is simple, effective and safe, and most patients report improved well-being on initiation of treatment. However, a proportion of individuals continue to suffer with symptoms despite achieving adequate biochemical correction. The management of such individuals has been the subject of controversy and of considerable public interest. The American Thyroid Association (ATA) and the European Thyroid Association (ETA) have recently published guidelines on the diagnosis and management of hypothyroidism. These guidelines have been based on extensive reviews of the medical literature and include sections on the role of combination therapy with L-T4 and liothyronine (L-T3) in individuals who are persistently dissatisfied with L-T4 therapy. This position statement by the British Thyroid Association (BTA) summarises the key points in these guidelines and makes recommendations on the management of primary hypothyroidism based on the current literature, review of the published positions of the ETA and ATA, and in line with best principles of good medical practice. The statement is endorsed by the Association of Clinical Biochemistry, (ACB), British Thyroid Foundation, (BTF), Royal College of Physicians (RCP) and Society for Endocrinology (SFE).
Topics: Disease Management; Drug Therapy, Combination; Humans; Hypothyroidism; Practice Guidelines as Topic; Thyroxine; Triiodothyronine
PubMed: 26010808
DOI: 10.1111/cen.12824