Thyroid function, sex hormones and sexual function: a Mendelian randomization study.

Hypothyroidism and hyperthyroidism are observationally associated with sex hormone concentrations and sexual dysfunction, but causality is unclear. We investigated whether TSH, fT4, hypo- and hyperthyroidism are causally associated with sex hormones and sexual function. We used publicly available summary statistics from genome-wide association studies on TSH and fT4 and hypo- and hyperthyroidism from the ThyroidOmics Consortium (N ≤ 54,288).

Effects of Thyroid Status on Regional Brain Volumes: A Diagnostic and Genetic Imaging Study in UK Biobank.

Background: Thyroid hormone is essential for optimal human neurodevelopment and may modify the risk of attention-deficit/hyperactivity disorder (ADHD). However, the brain structures involved are unknown and it is unclear if the adult brain is also susceptible to changes in thyroid status.

Methods: We used International Classification of Disease-10 codes, polygenic thyroid scores at different thresholds of association with thyroid traits (PT-values), and image-derived phenotypes in UK Biobank (n = 18 825) to investigate the effects of a recorded diagnosis of thyroid disease and genetic risk for thyroid status on cerebellar and subcortical gray matter volume.

Urinary Iodine Concentrations in Pregnant Women and Offspring Brain Morphology.

Severe maternal iodine deficiency during pregnancy leads to marked intellectual disability in the offspring. Although recent studies showed that even mild-to-moderate maternal iodine deficiency is associated with lower intelligence quotient and attention deficit hyperactivity disorder in offspring, the underlying neurobiological mechanism of these associations remains unknown. The aim of this study was to investigate the association of maternal iodine excretion during pregnancy with offspring brain morphology during pre-adolescence.

Severity of Proteinuria Is Directly Associated With Risk of Hypothyroidism in Adults.

Context: Proteinuria can cause or exacerbate hypothyroidism, possibly due to urinary loss of protein-bound thyroid hormone. However, the precise relationship between proteinuria and hypothyroidism remains unclear.

Objective: This work aimed to determine the prevalence of hypothyroidism in patients with proteinuria and the relationship between hypothyroidism and degree of proteinuria.

Thyroid Function and Physical Activity: A Population-Based Cohort Study.

Thyroid hormones are important metabolic regulators exerting effects in multiple systemic functions including muscular and cardiorespiratory function. Thyroid hormones may influence physical activity levels. However, there are currently no studies evaluating the association between thyroid function and physical activity levels in the general population.

Association of urinary bisphenols during pregnancy with maternal, cord blood and childhood thyroid function.

Background: Most pregnant women are exposed to bisphenols, a group of chemicals that can interfere with various components of the thyroid system.

Objectives: To investigate the association of maternal urinary bisphenol concentrations during pregnancy with maternal, newborn and early childhood thyroid function.

Methods: This study was embedded in Generation R, a prospective, population-based birth cohort (Rotterdam, the Netherlands).

Interpretation of thyroid function tests during pregnancy.

Thyroid hormones are crucial for normal pregnancy and fetal development. Large physiological changes occur during pregnancy, posing challenges for the correct interpretation of thyroid function tests. TSH concentrations are the principal first test to rule out thyroid disease taking into account trimester-specific reference ranges.

GWAS of thyroid stimulating hormone highlights pleiotropic effects and inverse association with thyroid cancer.

Thyroid stimulating hormone (TSH) is critical for normal development and metabolism. To better understand the genetic contribution to TSH levels, we conduct a GWAS meta-analysis at 22.4 million genetic markers in up to 119,715 individuals and identify 74 genome-wide significant loci for TSH, of which 28 are previously unreported.

Variation in Normal Range Thyroid Function Affects Serum Cholesterol Levels, Blood Pressure, and Type 2 Diabetes Risk: A Mendelian Randomization Study.

Observational studies have demonstrated that variation in normal range thyroid function is associated with major cardiovascular risk factors, including dyslipidemia, hypertension, type 2 diabetes (T2D), and obesity. As observational studies are prone to residual confounding, reverse causality, and selection bias, we used a Mendelian randomization (MR) approach to investigate whether these associations are causal or not. Two-sample MR analysis using data from the largest available genome-wide association studies on normal range thyrotropin (TSH) and free thyroxine (fT4) levels, serum lipid levels, blood pressure measurements, T2D, and obesity traits (body mass index [BMI] and waist/hip ratio).

Thyroid Function Test Abnormalities in Twin Pregnancies.

Compared with singletons, a twin pregnancy is associated with a larger thyroid hormone demand and an increased stimulation of gestational thyroid function due to higher concentrations of human chorionic gonadotropin. However, such effects have been sparsely quantified. The aim of this study was to evaluate thyroid function and thyroid function test abnormalities in twin pregnancies during early and late pregnancy compared with singletons.

Insights Into the Mechanism of MCT8 Oligomerization.

Mutations in the thyroid hormone transporter monocarboxylate transporter 8 (MCT8) result in MCT8 deficiency, characterized by severe intellectual and motor disability. The MCT8 protein is predicted to have 12 transmembrane domains (TMDs) and is expressed as monomers, homodimers, and homo-oligomers. This study aimed to delineate the mechanism of MCT8 oligomerization.

Urinary Concentrations of Phthalate Metabolite Mixtures in Relation to Serum Biomarkers of Thyroid Function and Autoimmunity among Women from a Fertility Center.

Background: Although previous epidemiological studies have explored associations of phthalate metabolites with thyroid function, no studies to date have assessed associations of mixtures with thyroid function and autoimmunity among potentially susceptible subgroups such as subfertile women.

Objective: We aimed to explore associations of mixtures of urinary phthalate metabolites with serum markers of thyroid function and autoimmunity.

Methods: This cross-sectional study included 558 women attending a fertility center who provided one spot urine and one blood sample at enrollment (2005-2015).

Association of maternal thyroid function with birthweight: a systematic review and individual-participant data meta-analysis.

Background: Adequate transplacental passage of maternal thyroid hormone is important for normal fetal growth and development. Maternal overt hypothyroidism and hyperthyroidism are associated with low birthweight, but important knowledge gaps remain regarding the effect of subclinical thyroid function test abnormalities on birthweight-both in general and during the late second and third trimester of pregnancy. The aim of this study was to examine associations of maternal thyroid function with birthweight.

Thyroid Function Affects the Risk of Stroke via Atrial Fibrillation: A Mendelian Randomization Study.

Context: Observational studies suggest that variations in normal range thyroid function are associated with cardiovascular diseases. However, it remains to be determined whether these associations are causal or not.

Objective: To test whether genetically determined variation in normal range thyroid function is causally associated with the risk of stroke and coronary artery disease (CAD) and investigate via which pathways these relations may be mediated.

The Genetic Basis of Thyroid Function: Novel Findings and New Approaches.

Context: Genetic factors are major determinants of thyroid function. Over the last two decades, multiple genetic variants have been associated with variations in normal range thyroid function tests. Most recently, a large-scale genome-wide association study (GWAS) doubled the number of known variants associated with normal range thyrotropin (TSH) and free thyroxine (FT4) levels.

Familial dysalbuminaemic hyperthyroxinaemia interferes with current free thyroid hormone immunoassay methods.

Objective: Familial dysalbuminaemic hyperthyroxinaemia (FDH), most commonly due to an Arginine to Histidine mutation at residue 218 (R218H) in the albumin gene, causes artefactual elevation of free thyroid hormones in euthyroid individuals. We have evaluated the susceptibility of most current free thyroid hormone immunoassay methods used in the United Kingdom, Europe and Far East to interference by R218H FDH.

Methods: Different, one- and two-step immunoassay methods were tested, measuring free T4 (FT4) and free T3 (FT3) in 37 individuals with genetically proven R218H FDH.

Maternal Iodine Status During Pregnancy Is Not Consistently Associated with Attention-Deficit Hyperactivity Disorder or Autistic Traits in Children.

Background: Severe iodine deficiency during pregnancy can cause intellectual disability, presumably through inadequate placental transfer of maternal thyroid hormone to the fetus. The association between mild-to-moderate iodine deficiency and child neurodevelopmental problems is not well understood.

Objectives: We investigated the association of maternal iodine status during pregnancy with child attention-deficit hyperactivity disorder (ADHD) and autistic traits.

Overt Thyroid Dysfunction and Anti-Thyroid Antibodies Predict Response to Anti-PD-1 Immunotherapy in Cancer Patients.

Thyroid dysfunction is among the most common adverse effects during anti-programmed cell death 1 (PD-1) immunotherapy, and alongside correlations with elevated anti-thyroid antibodies (ATAb), studies have found correlations with survival. However, the exact relations remain to be clarified. We, therefore, aimed at clarifying the relationship between thyroid dysfunction, ATAbs, and survival in anti-PD-1 treated cancer patients.

Longitudinal Analysis of the Effect of Radioiodine Therapy on Ovarian Reserve in Females with Differentiated Thyroid Cancer.

Although international guidelines have become more conservative on the use of radioactive iodine (RAI) therapy, it is still one of the cornerstones of the treatment of patients with advanced differentiated thyroid cancer (DTC). As a large proportion of females diagnosed with DTC is in their reproductive years, knowledge about the effect of RAI on their gonadal and reproductive function is important. Earlier studies evaluating Anti-Müllerian hormone (AMH) as a representative of ovarian reserve were either cross-sectional, had relatively low numbers, had no patients with multiple RAI therapies, or had a relatively short follow-up.

Thyroid Function and the Risk of Fibrosis of the Liver, Heart, and Lung in Humans: A Systematic Review and Meta-Analysis.

Fibrotic diseases have an unclear etiology and poor prognosis. Fluctuations in thyroid function may play a role in the development of fibrosis, but evidence is fragmented and inconclusive. This systematic review and meta-analysis aimed to investigate the association of thyroid function with fibrotic diseases of the liver, heart, and lung in humans.

Unique near-complete deletion of GLI2 in a patient with combined pituitary hormone deficiency and post-axial polydactyly.

Introduction: Combined pituitary hormone deficiency (CPHD) can cause a broad spectrum of health problems, ranging from short stature only, to convulsions or even death. In the majority of patients, the cause is unknown.

Methods: The idex case had unexplained CPHD, pituitary anomalies on MRI and polydactyly.