Hypothyroidism

The thyroid gland is butterfly-shaped in the lower part of your neck, in front of your windpipe. The thyroid gland produces hormones that influence other glands and many physiological functions. Thyroid hormones regulate your body’s metabolism, which refers to all the chemical processes that take place in your body. This includes the production of energy and hormones, tissue growth, elimination of waste products, and the distribution of nutrients in the blood.

Your thyroid produces two thyroid hormones: thyroxine (T4) and triiodothyronine (T3). These hormones are secreted into your blood circulation and regulate the function of every cell and tissue in your body. T4 and T3 are necessary for good health, metabolism, and energy level control.

The hypothalamus and pituitary gland in your brain regulate T4 and T3 production. When T4 and T3 levels are low, the hypothalamus produces thyrotropin-releasing hormone (TRH) to signal the pituitary gland to produce thyroid-stimulating hormone (TSH) and vice versa. The TSH travels in the bloodstream and signals the thyroid gland to produce more T4 and T3. When T4 and T3 levels are high, the pituitary gland stops producing TSH.

The causes of hypothyroidism are:

1. Hashimoto’s Thyroiditis is the most common cause of hypothyroidism in the United States. Hashimoto’s Thyroiditis is an autoimmune disorder. It occurs when abnormal blood antibodies and white blood cells attack and damage the thyroid cells. This leaves few thyroid cells, which cannot produce adequate thyroid hormones.
2. In some parts of the world, a lack of iodine is the most common cause of hypothyroidism. This is rarely seen in the United States. In the United States, iodine is added to salt, food, and water.
3. Pregnancy is a physiological state that increases the need for Levothyroxine. Some women can develop hypothyroidism during pregnancy. Some infants are born without a functioning thyroid gland. All infants in the United States are tested for hypothyroidism at birth.
4. Thyroid gland surgery- for hyperthyroidism, thyroid nodules or thyroid cancer, radioactive iodine therapy, or radiation treatments that affect part or all of the thyroid glands can also cause hypothyroidism.
5. Less common causes of hypothyroidism include infections, certain medications, such as lithium, and excessive iodine intake.
6. In rare cases, hypothyroidism can occur with a normal thyroid gland. This often occurs when there is a problem with the hypothalamus or the pituitary gland. The pituitary gland does not produce enough TSH. In turn, the thyroid gland cannot produce T4 and T3 without the TSH signal. This is called central or secondary hypothyroidism.

The risk factors for hypothyroidism are:

1. Women are more likely than men to develop thyroid disease.
2. A family history of thyroid disease.
3. Medical conditions, including diabetes, vitiligo (an autoimmune disease that causes light-colored patches of skin), pernicious anemia, and premature gray hair, are associated with hypothyroidism.
4. An iodine deficiency can cause hypothyroidism. This is more common in the developing world.
5. Medications such as lithium carbonate, amiodarone, immunotherapy, and interferon alpha.
6. Radiation treatments, radioactive iodine therapy, or removal of all or part of the thyroid gland can affect its function and cause hypothyroidism.

The symptoms of hypothyroidism usually develop slowly over months or years. Hypothyroidism causes your metabolic rate to slow down.

Symptoms of hypothyroidism:

1. Fatigue, feeling sluggish.
2. Dry, flaky skin
3. Puffiness of eyes
4. Increased hair loss – scalp and eyebrows.
5. Brittle nails
6. Increased sleepiness
7. Cold intolerance
8. Muscle aches and cramps
9. Constipation
10. Menstrual irregularities in women
11. Infertility
12. Weight gain
13. Memory impairment, decreased motivation, and sometimes depressed mood.

Signs of hypothyroidism:

• Deep or hoarse voice
• Swollen neck
• Slow pulse and abnormalities in blood pressure
• High cholesterol levels

In severe cases, heart failure or coma (Myxedema). This consists of tissue swelling, fluid buildup in the heart and lungs, slowed muscle reflexes, and problems with thinking skills. You should call emergency medical services if you or a person you know develops signs of myxedema coma.

Dr Reena Thomas will help diagnose this condition with a comprehensive medical evaluation and physical examination. She will order blood tests to check your thyroid function and thyroid autoantibodies. She may do an ultrasound of the neck in the office to evaluate your thyroid gland and look for any abnormalities in its structure, such as the presence of any thyroid nodules.