Hypothyroidism is one of the most prevalent endocrine disorders, second only to diabetes. Hypothyroidism diagnosis can be difficult in view of its varied and non-specific symptoms. The reason is that thyroid hormones affect virtually every organ system in the body. At the same time, the severity of thyroid hormone deficiency may vary and does not always correlate with the changes in laboratory testing results. Clinical presentation of patients with hypothyroidism may include multiple symptoms and, as a result, it can be difficult to diagnose this disorder, especially in elderly and polymorbid individuals. In some patients, the prevailing symptoms indicate that only a particular system is affected. Thus, there are diseases known as the "masks" of hypothyroidism, and this review is focused on their clinical manifestations. Conditions that may be running under the "mask" of hypothyroidism include diastolic hypertension, dyslipidemia, hydropericardium, chronic constipation, biliary lithiasis, polyarthritis, alopecia, onycholysis, depression, dysfunctional uterine bleeding, infertility, anemia, etc. Due to a variety of clinical signs and symptoms, a patient with hypothyroidism may get an appointment with any medical specialist or receive a follow-up care provided in parallel by multiple specialists. Physicians should be aware of potential hypothyroidism and specific effects of the underactive thyroid on patient’s organs and systems. It is necessary to obtain a thorough medical history about comorbidities which would help to figure out that hypothyroidism is the cause of co-occurring conditions. KEYWORDS: autoimmune thyroiditis, hypothyroidism, subclinical hypothyroidism, euthyroidism, dyslipidemia, cardiovascular diseases, arterial hypertension FOR CITATION: Verbovoy A.F., Dolgikh Yu.A., Verbovaya N.I. Hypothyroidism is an interdisciplinary problem. Russian Medical Inquiry. 2022;6(9):509–515 (in Russ.). DOI: 10.32364/2587-6821-2022-6-9-509-515.
