“Subclinical” pathologies or conditions are mild forms of hyperthyroidism or hypothyroidism, characterized by thyroid hormones’ levels in the normal range, but slightly altered TSH (thyroid stimulating hormone).
Subclinical hyperthyroidism is a condition defined by TSH levels comprised between 0.1 and 0.4 mIU/L, with thyroid hormones (T3 and T4) in the normal range. This condition is often underestimated and not treated in clinical practice, but important symptoms in mild forms appear in this condition, such as palpitations, weakness, heat intolerance, sleep disturbances, arrhythmias, weight loss, tachycardia, goiter.
The more TSH level stays under the normal range, the more the patient is exposed to long-term risks, mainly cardiovascular and bone-related.
Subclinical hypothyroidism is defined as a condition characterized by TSH levels between 4.0 and 10.0 mIU/L, with thyroid hormones (T3 and T4) in the normal range. Many experts agree to consider subclinical hypothyroidism as an initial and mild insufficiency of the thyroid gland. Subclinical hypothyroidism can manifest with typical hypothyroidism symptoms, but less evident, thus harder to diagnose. Some of these symptoms are drowsiness, slow thinking, memory loss, weight gain, asthenia, cold intolerance, constipation, dryer skin, hair and nails fragility. Taking action in this phase of the pathology allows to protect patients form long-term risks, such as progression to overt form of hypothyroidism, increased risk of metabolic syndrome and cardiovascular diseases, compromised fertility and increased risk of malignant nodules.