Increased Thyroid Function in Haemochromatosis

Williams, Robert

doi:10.1136/bmj.1.5129.1078

Cited by 5 publications

(1 citation statement)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…HFE C282Y occurs in linkage disequilibrium with class I alleles at human leukocyte antigen (HLA)-A and -B loci and with the hemochromatosis ancestral haplotype HLA-A*03,B*07 on chromosome 6p (1,36). In Western European whites, Hashimoto thyroiditis and Graves' disease have been associated with HLA class II loci (37)(38)(39), but there are few reports of these disorders in whites with hemochromatosis phenotypes or C282Y homozygosity (6,40,41). This suggests that linkage disequilibrium of HFE C282Y with HLA class II loci is not great, that the ancestral hemochromatosis haplotype does not include susceptibility alleles for common autoimmune thyroid disorders, or that there are other susceptibility factors for Hashimoto thyroiditis and Graves' disease.…”

Section: Thyroid Levels In C282y Homozygotesmentioning

confidence: 99%

Thyroid-Stimulating Hormone and Free Thyroxine Levels in Persons with HFE C282Y Homozygosity, a Common Hemochromatosis Genotype: The HEIRS Study

Barton¹,

Leiendecker–Foster

Reboussin

et al. 2008

Thyroid

View full text Add to dashboard Cite

for the Hemochromatosis and Iron Overload Screening Study Research InvestigatorsBackground: Relationships of thyroid and iron measures in large cohorts are unreported. We evaluated thyroidstimulating hormone (TSH) and free thyroxine (T4) in white participants of the primary care-based Hemochromatosis and Iron Overload Screening (HEIRS) Study. Methods: We measured serum TSH and free T4 in 176 HFE C282Y homozygotes without previous hemochromatosis diagnoses and in 312 controls without HFE C282Y or H63D who had normal serum iron measures and were matched to C282Y homozygotes for Field Center, age group, and initial screening date. We defined hypothyroidism as having TSH >5.00 mIU=L and free T4 <0.70 ng=dL, and hyperthyroidism as having TSH <0.400 mIU=L and free T4 >1.85 ng=dL. Multivariate analyses were performed using age, sex, Field Center, log 10 serum ferritin (SF), HFE genotype, log 10 TSH, and log 10 free T4. Results: Prevalences of hypothyroidism in C282Y homozygotes and controls were 1.7% and 1.3%, respectively, and of hyperthyroidism 0% and 1.0%, respectively. Corresponding prevalences did not differ significantly. Correlations of log 10 SF with log 10 free T4 were positive ( p ¼ 0.2368, C282Y homozygotes; p ¼ 0.0492, controls). Independent predictors of log 10 free T4 were log 10 TSH (negative association) and age (positive association); positive predictors of log 10 SF were age, male sex, and C282Y homozygosity. Proportions of C282Y homozygotes and controls who took medications to supplement or suppress thyroid function did not differ significantly. Conclusions: Prevalences of hypothyroidism and hyperthyroidism are similar in C282Y homozygotes without previous hemochromatosis diagnoses and controls. In controls, there is a significant positive association of SF with free T4. We conclude that there is no rationale for routine measurement of TSH or free T4 levels in hemochromatosis or iron overload screening programs.

show abstract

Section: Thyroid Levels In C282y Homozygotesmentioning

confidence: 99%

Thyroid-Stimulating Hormone and Free Thyroxine Levels in Persons with HFE C282Y Homozygosity, a Common Hemochromatosis Genotype: The HEIRS Study

Barton¹,

Leiendecker–Foster

Reboussin

et al. 2008

Thyroid

View full text Add to dashboard Cite

show abstract

Thyroid Disease in Hemochromatosis

Edwards¹

1983

Arch Intern Med

View full text Add to dashboard Cite

Endocrine dysfunction in hereditary hemochromatosis

Pelusi

Gasparini

Bianchi

et al. 2016

J Endocrinol Invest

View full text Add to dashboard Cite

Hereditary hemochromatosis (HH) is a genetic disorder of iron overload and subsequent organ damage. Five types of HH are known, classified by age of onset, genetic cause, clinical manifestations and mode of inheritance. Except for the rare form of juvenile haemochromatosis, symptoms do not usually appear until after decades of progressive iron loading and may be triggered by environmental and lifestyle factors. Despite the last decades discovery of genetic and phenotype diversity of HH, early studies showed a frequent involvement of the endocrine glands where diabetes and hypogonadism are the most common encountered endocrinopathies. The pathogenesis of diabetes is still relatively unclear, but the main mechanisms include the loss of insulin secretory capacity and insulin resistance secondary to liver damage. The presence of obesity and/or genetic predisposition may represent addictive risk factor for the development of this metabolic disease. Although old cases of primary gonad involvement are described, hypogonadism is mainly secondary to selective deposition of iron on the gonadotropin-producing cells of the pituitary gland, leading to hormonal impaired secretion. Cases of hypopituitarism or selected tropin defects, and abnormalities of adrenal, thyroid and parathyroid glands, even if rare, are reported. The prevalence of individual gland dysfunction varies enormously within studies for several bias due to small numbers of and selected cases analyzed, mixed genotypes and missing data on medical history. Moreover, in the last few years early screening and awareness of the disease among physicians have allowed hemochromatosis to be diagnosed in most cases at early stages when patients have no symptoms. Therefore, the clinical presentation of this disease has changed significantly and the recognized common complications are encountered less frequently. This review summarizes the current knowledge on HH-associated endocrinopathies.

show abstract

Increased Thyroid Function in Haemochromatosis

Cited by 5 publications

References 8 publications

Thyroid-Stimulating Hormone and Free Thyroxine Levels in Persons with HFE C282Y Homozygosity, a Common Hemochromatosis Genotype: The HEIRS Study

Thyroid-Stimulating Hormone and Free Thyroxine Levels in Persons with HFE C282Y Homozygosity, a Common Hemochromatosis Genotype: The HEIRS Study

Thyroid Disease in Hemochromatosis

Endocrine dysfunction in hereditary hemochromatosis

Contact Info

Product

Resources

About