We recommend against screening* asymptomatic nonpregnant adults aged 18 years and older for thyroid dysfunction in primary care settings (strong recommendation, low-certainty evidence)
This recommendation does not apply to adults who have the following risk factors for thyroid dysfunction:
- Individuals who have had a previously diagnosed thyroid disease or surgery;
- Individuals receiving thyroid medications or medications that may affect thyroid function (i.e., lithium, amiodarone);
- Individuals with previous or ongoing exposure to thyroid radioiodine therapy or head and neck radiotherapy; or
- Individuals with pituitary or hypothalamic diseases.
*Screening refers to measuring levels of thyroid-stimulating hormone (TSH) in patients with no apparent signs or symptoms of thyroid dysfunction. Screening differs from measuring levels of TSH among patients who are experiencing signs and symptoms (e.g., fatigue, weight gain, menstrual irregularities, goitre) or are at risk for thyroid dysfunction due to secondary causes (e.g., pituitary or hypothalamic diseases) to investigate possible thyroid dysfunction.