Unterfunktion der Schilddrüse (Hypothyreose)

Hypothyroidism is characterized by the cells of the body being undersupplied with thyroid hormones (T3 and T4). The cause is insufficient or absent thyroid hormone production. Approximately 10% of the population are affected by this condition.

Latent hyperthyroidism

A reduction in hormone production by the thyroid gland is registered by the anterior pituitary gland, which stimulates the thyroid gland to increase TSH secretion. A higher TSH level boosts hormone production by the thyroid. If the thyroid is able to meet TSH requirement by increasing hormone production, T3 and T4 levels return to normal, whereas the TSH level remains slightly high. The combination of T3 and T4 being within the normal range and TSH being slightly high is termed latent hypothyroidism. When the thyroid hormone level is within the normal range, there are no or only very mild subjective complaints.

Manifest hypothyroidism

A reduction in hormone production by the thyroid is registered by the anterior pituitary gland, which stimulates the thyroid to increase THS secretion. However due to advanced failure, the thyroid gland is unable to increase hormone production. As a result, the TSH level remains above the norm or increases further, while T3 and T4 remain low. The lack of thyroid hormones leads to subjective complaints, which correspond in scope to the degree of thyroid hormone deficiency. 

With an underactive thyroid, there are both physical and psychological complaints.

The most common complaints with hypofunction are:

• Fatigue, listlessness and weakness
• Weight loss
• Hoarseness
• Hypersensitivity to cold
• Constipation
• Cycle disorder and reduced fertility
• Dry skin, increased hair loss and brittle nails
• Elevated blood lipids

The most common psychological complains with under-function are:

• Depression
• Poor memory
• Disinterest and apathy

Therapy:

Thyroid hormone (levothyroxine)

The aim of therapy is to normalize thyroid hormone levels (euthyroidism).