Demystifying Thyroid Disease

More than half of the Americans suffering from a thyroid disorder go undiagnosed. During January, National presents the opportunity to educate populations on the significance of this small, butterfly-shaped gland located just above your collarbone and in front of the windpipe. This gland produces hormones that regulate the body’s metabolic rate and impacts vital functions such as brain development, muscle strength, digestive function, breathing, heart rate, body temperature and bone maintenance.

According to the American Thyroid Association, 1 in 10 people suffer from a thyroid disorder, and at least 1 in 8 women will develop a thyroid disorder during their lifetime. By raising awareness of thyroid disease, patients can be more effective advocates for themselves and request testing and treatment.

Disease Identification and Treatment

Disorders of the thyroid gland include hyperthyroidism, hypothyroidism, large glands (goiters) and a variety of cancers. The most common forms of thyroid disease are hyperthyroidism and hypothyroidism. A gland that is making too much hormone is hyperactive. Too little is termed hypoactive. Because nearly all parts of our bodies are sensitive to thyroid hormone, abnormal levels can cause a huge variety of problems and symptoms. High levels can cause weight loss, rapid heartbeat, anxiety, muscle weakness and more. Low thyroid hormone levels can cause weight gain, slowed heartbeat, fatigue, feeling cold, constipation and more.

Thyroid cancer refers to thyroid cells that have the potential to multiply abnormally or to spread to other organs such as the lungs or bones. In 2021 thyroid cancers were 2.3% of all new cancer cases, but only 0.4% of all cancer deaths. New cases outnumbered deaths 20 to 1, reflecting that most thyroid cancers are successfully treated. Signs and symptoms that do need evaluation are a lump in the neck or thyroid gland, voice changes and/or difficulty swallowing. While there are many types of thyroid cancer, the four major types are: • Papillary Thyroid Cancer – The most common thyroid cancer, this malignancy grows slowly and often spreads to lymph nodes in the neck. It may spread further if not treated.

• Follicular Thyroid Cancer – The second most common cancer affecting the thyroid, it may present with lumps in the gland but is more likely to spread via the blood to other organs than to the lymph nodes.

• Medullary Thyroid Cancer – Often hereditary and rare, it develops from the small islands of calcitonin cells found in the thyroid gland. These cells make calcitonin, a different hormone than thyroid hormone.

• Anaplastic Thyroid Cancer – The rarest and most aggressive form of thyroid cancer, this tumor has often spread before being diagnosed and is still very difficult to control.

Options differ for each type of thyroid problem. Endocrinologists (specialists in diseases of glands that secrete hormones into the blood) use a patient’s medical records, physical exam, blood work and imaging tests (such as ultrasound and nuclear scans) to manage thyroid cancers and other thyroid disorders. Measures such as skinny needle biopsies, surgeries of the gland or lymph nodes, radioactive iodine scans or treatments, chemotherapy or X-ray therapy may be needed. Medications are available to slow down overactive glands, and thyroid hormone supplements can make up for underactive glands. Thyroid hormone pills are one of the most prescribed of all medicines.

Causes of thyroid disease

Conditions that can cause high or low thyroid function include:

• Thyroiditis: Any condition where there is inflammation or damage of thyroid cells may be painful or painless.

• Hashimoto’s thyroiditis: A painless disease, Hashimoto’s thyroiditis is an often inherited autoimmune condition in which the body’s immune cells attack and damage the thyroid.

• Postpartum thyroiditis: Usually a temporary condition, this instance of inflammation occurs in 5% to 9% of women after childbirth. Experts are unsure of the causes, but the condition is seen more in patients with antithyroid antibodies before pregnancy.

• Iodine deficiency: Iodine is used by the thyroid to produce hormones. Iodine deficiency affects several million people around the world. Iodine deficiency is uncommon in the United States, mainly due to the iodine found in iodized salt and some foods such as dairy. Iodine requirements are higher in pregnancy and during breastfeeding.

Conditions that can cause hyperthyroidism include:

• Graves’ disease: In this condition, the entire thyroid gland can be overactive and produce too much hormone. This is also called toxic diffuse goiter. As with Hashimoto’s, this condition is caused by our immune system producing antibodies. These antibodies stimulate thyroid cells to overproduce hormones. The gland can get quite large or just be too busy. This condition may involve a special inflammation around the eyes that can be severe.

• Autonomous Nodules: Hyperthyroidism can be caused by groups of cells (lumps or nodules) that are overactive within the thyroid. If there are more than one of these, it is called a toxic multi-nodular goiter.

• Thyroiditis: If inflammation causes thyroid cells to spill thyroid hormone into the blood, levels can be high. This may resolve back to normal or progress to gland damage and underactivity.

The thyroid problems we have now are not new; they were described in ancient times. Lifestyle doesn’t seem to have major effects on thyroid health. Women who are pregnant or planning a pregnancy may need extra iodine supplements. All of us would benefit from a diet of real food with plenty of colorful vegetables and fruit to provide the antioxidants that limit inflammation. While science has demystified many aspects of thyroid disease, we clearly have much more to learn about our thyroid glands. Mysteries remain, but most patients can expect to do well with proper diagnosis and treatment.

David Scarborough, MD, is a professor of clinical medicine and division chief for endocrinology at Ochsner LSU Health Shreveport.