Thyroid Disorder


Thyroid function in the neonatal period

  • An estimated 1% of babies with Down syndrome have a raised TSH on newborn screening, but classical congenital hypothyroidism due to thyroid dysgenesis is not common.
  • Raised TSH should prompt further investigation, and consideration of treatment with thyroxine.
  • Borderline thyroid dysfunction in the neonate may be transient, and when treatment is started in these cases , treatment should be stopped after the age of 2 years and thyroid function reassessed off treatment.
  • At present there is no hard evidence to justify routinely treating infants with Down syndrome with thyroxine, if they have normal thyroid function.

Thyroid function beyond the neonatal period

  • Thyroid dysfunction , mainly hypothyroidism occurs more commonly in people with Down syndrome at all ages, when compared with the general population.
  • The prevalence of autoimmune thyroiditis increases with age in Down syndrome.
  • Clinical diagnosis of hypothyroidism may be unreliable in Down syndrome because of overlap with features commonly seen in the syndrome e.g. dry skin, thin hair and constipation.
  • Screening for thyroid dysfunction is required throughout life.
  • Capillary TSH testing is a practical reliable method. This can be done by fingerprick samples and on the same cards as used for newborn screening.
  • Mild elevation of TSH with normal fT4 and no symptoms may not require treatment.
  • Hyperthyroidism is less common than hypothyroidism, but occurs more frequently than in the general population.

DSMIG Guidance

Thyroid Disorder

Guideline for Basic Essential Medical Surveillance

DSMIG’s evidence-based guideline for basic essential medical surveillance.

Last updated: 2001

Presentations at DSMIG Meetings

Materials from meetings are available for members only who need to log in to access them. For details on how to become a member click here.

Additional Resources

Thyroid Disorder – Down’s syndrome association health series leaflet 

Updated 2013


Book Chapter - Endocrine Disorders – Thyroid Disorder

Malcolm Donaldson and Kath Leyland

ds-current-perspectives-book-coverDown Syndrome – Current Perspectives

Edited by Richard Newton , Shiela Puri and Liz Marder