How is Hypothyroidism Diagnosed
How is Hypothyroidism Diagnosed?

Hypothyroidism is detected by a thyroid profile assessing T3, T4, and TSH levels.1

The TSH blood test measures the amount of TSH in your blood.1

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Many people may be living with hypothyroidism without realizing they have it. This may be because symptoms develop slowly and often mimic other conditions.2

In most cases of hypothyroidism, there are:

  • High TSH levels1
  • Lower levels of thyroid hormones1

Since thyroid hormone and TSH levels may change throughout life,3 they should be checked starting at the age of 35 and every 5 years thereafter, as it is a cost-effective measure in the context of the periodic health examination.4 Some people may need to get their TSH levels tested more often than others. Learn More.

The Difficulty with Diagnosing Hypothyroidism

The Difficulty with Diagnosing Hypothyroidism

Hypothyroidism is fairly easy to diagnose through a simple TSH blood test1; however, it is estimated that up to 50% of people with thyroid disease don’t even know they have it.5 This may be because symptoms develop slowly and often mimic other conditions.2

For example, depression and menopause share some similar symptoms with hypothyroidism, such as fatigue, weight gain, and depressed mood.6,7

Timing may also be a factor that confuses a diagnosis of hypothyroidism. It is more common in people over 50,8 in women who have recently given birth, and during menopause.9 Symptoms of hypothyroidism may not appear until a few months after childbirth. They are frequently confused as normal symptoms of recovery after childbirth.10

Abbreviations: T3, Triiodothyronine; T4, Thyroxine; TSH, Thyroid Stimulating Hormone

References:

1. Hypothyroidism (underactive thyroid): diagnosis. Mayo Clinic. Accessed May 22, 2023. https://www.mayoclinic.org/diseases-conditions/hypothyroidism/diagnosis-treatment/drc-20350289 2. Hypothyroidism (underactive thyroid): overview. Mayo Clinic. Accessed May 22, 2023. https://www.mayoclinic.org/diseases-conditions/hypothyroidism/symptoms-causes/syc-20350284 3. Leng O, Razvi S. Hypothyroidism in the older population. Thyroid Res. 2019;12:2. 4. Villar HC, Saconato H, Valente O, Atallah AN. Thyroid hormone replacement for subclinical hypothyroidism. Cochrane Database Syst Rev. 2007;(3):CD003419. 5. About thyroid disease. Thyroid Foundation of Canada. Accessed May 22, 2023. https://thyroid.ca/thyroid-disease/ 6. Thyroid and menopause. British Thyroid Foundation. Accessed May 22, 2023. https://www.btf-thyroid.org/thyroid-and-menopause-article 7. Asamoah T. The link between hypothyroidism and depression. GoodRx Health. Accessed May 23, 2023. https://www.goodrx.com/conditions/hypothyroidism/depression 8. Hypothyroidism. MedlinePlus. Accessed May 22, 2023. https://medlineplus.gov/ency/article/000353.htm 9. Mayo Clinic Q and A: women and thyroid disease. Mayo Clinic. Accessed May 22, 2023. https://newsnetwork.mayoclinic.org/discussion/mayo-clinic-q-and-a-women-and-thyroid-disease/ 10. Postpartum thyroiditis. Johns Hopkins Medicine. Accessed May 22, 2023. https://www.hopkinsmedicine.org/health/conditions-and-diseases/postpartum-thyroiditis