Overview Of Hypothyroidism

Hypothyroidism is defined as having a reduced level of thyroid hormones in the bloodstream due to the thyroid gland becoming underactive and therefore not producing enough of the mentioned hormones. Thyroid hormones are very important as they regulate the body's metabolic rate.

If hypothyroidism is left untreated, it can result in the development of numerous health-related conditions such as peripheral neuropathy, heart conditions such as atrial fibrillation and heart failure as well as mental health issues such as depression.

Causes

There are numerous conditions and scenarios that can result in hypothyroidism and they include the following:

• Autoimmune diseases -  The most common autoimmune condition that results in hypothyroidism is known as Hashimoto's thyroiditis. An autoimmune condition is one where the body's own immune system produces antibodies that attacks normal tissue, in this case the thyroid gland. Essentially, this condition causes the thyroid gland to become underactive and results in a reduced amount of thyroid hormones in the body.
• Radioactive iodine therapy - this oral nuclear medicine therapy is used to treat patients who are diagnosed with hyperthyroidism, where too much thyroid hormone is produced by the thyroid gland. In some cases, though, this form of treatment can work too well and therefore result in permanent hypothyroidism.
• Thyroid surgery - removing a portion or large section of the thyroid gland can result in a reduction of thyroid hormone production. 
• Radiation therapy - radiation therapy that is used to treat certain cancers involving the head and neck can negatively affect the thyroid gland which may lead to hypothyroidism.
• Medications - certain medications such as lithium, which is used to manage mental health conditions such as bipolar mood disorder, can cause hypothyroidism.

Symptoms

Patients in different age groups who are diagnosed with hypothyroidism tend to display different signs and symptoms of this condition. They are as follows:

Adults

• Increased sensitivity to cold.
• Fatigue.
• Impaired memory.
• Decreased appetite.
• Weight gain.
• Dry skin.
• Puffy face.
• Thinning hair.
• Depression.
• Decreased heart rate.
• Muscle and/or joint aches, tenderness, stiffness and weakness.
• Hoarseness.
• Constipation.
• Irregular or heavy menstrual periods.
• Elevated blood cholesterol levels.

READ Thyroid Hormones, Iodine Deficiency and Hypothyroidism

Infants

Hypothyroidism can develop in newborns and infants. The signs and symptoms in this age group include the following:

• Jaundice.
• A large, protruding tongue.
• Frequent choking, especially when feeding.
• A puffy appearance to the face.
• Failure to grow and develop normally.
• Poor muscle tone.
• Constipation.
• Excessive sleepiness.
• If left untreated, hypothyroidism can result in severe mental and physical restrictions.

Children and teenagers

The signs and symptoms of hypothyroidism in this age group is the same as in adults do, but they can also experience the following issues:

• Delayed development of permanent teeth.
• Poor growth that results in developing a short stature.
• Poor mental development.
• Delayed puberty which can affect fertility.