- By Cynthia Weiss
Mayo Clinic Q and A: What is Hashimoto’s thyroiditis?
DEAR MAYO CLINIC: My sister was diagnosed recently with Hashimoto's thyroiditis. She mentioned having to take medication and being on a special diet. Is there anything else she can do to manage symptoms? Am I am at risk for this condition, too?
ANSWER: Hashimoto's thyroiditis is a condition in which your immune system attacks your thyroid. It is named after a Japanese physician who first described the condition in the early 1900s. Hashimoto’s thyroiditis, also known as Hashimoto's disease, is the most common cause of hypothyroidism, or underactive thyroid, in the U.S.
Women experience thyroid problems in far greater numbers than men, and it is estimated that 1 in 8 women can develop a thyroid condition during their lifetime. While Hashimoto's thyroiditis primarily affects middle-aged women, it also occurs in women of any age, as well as in men and children.
People who get Hashimoto's thyroiditis often have family members who have thyroid disease or other autoimmune diseases. Patients with thyroid issues should tell their children and immediate relatives about their condition, so they can be aware and determine if testing is appropriate. While you may not have any symptoms of thyroid issues now, you can speak to your health care provider about whether you should have your thyroid checked.
Hashimoto's thyroiditis typically progresses slowly, over years. In some cases, people may not notice the signs or symptoms of Hashimoto's thyroiditis, as thyroid function can be normal. However, in most cases, a decrease in thyroid hormone production results in chronic inflammation. People may first notice a swelling at the front of the throat.
Other signs and symptoms of hypothyroidism may include fatigue, feeling cold, unexplained weight gain, dry skin, depressed mood, memory issues, constipation, menstrual changes, muscle weakness, or aches and pain. Fertility may be a sign for some women. Some patients with hypothyroidism may go undiagnosed for prolonged periods of time.
Typically, if you have the symptoms of hypothyroidism, undergoing a simple blood test to check your thyroid-stimulating hormone, or TSH, as well as free T4 levels can determine if your thyroid is underactive or not.
Thyroid-stimulating hormone is secreted by the pituitary, which is part of your brain. This hormone provides a measurable signal within the blood to help assess thyroid health. In the most common forms of hypothyroidism, thyroid-stimulating hormone promptly rises when thyroid hormone becomes insufficient for a person. This means a person may have a free T4 thyroid hormone level that still falls within the population normal range, but if the level is not appropriate for that person, the thyroid-stimulating hormone can be expected to be consistently elevated on blood testing.
Should thyroid blood test results raise the question of hypothyroidism, your health care team will advise you if additional testing is warranted.
Recommendations for managing thyroid levels are based on clinical factors, so each person may be different. In some cases, close monitoring with serial thyroid blood tests will be advisable, while in other cases, initiation of thyroid hormone replacement therapy may be indicated. Your sister should visit with an endocrinologist who can help her effectively manage her condition.
Most patients with hypothyroidism requiring therapy can be successfully managed with an oral medication called levothyroxine. Choices include generic or brand-name forms of this medication that need be taken once daily. Your health care team can advise you in more detail about these options.
If hypothyroidism is the cause of a person's symptoms, the symptoms should gradually resolve once thyroid hormone levels are back in the normal range. After thyroid hormone replacement therapy is started, thyroid blood tests are typically checked about every six weeks until the levels are in target range and felt to be stable. Subsequent tests may be performed every six months to one year.
If your sister is receiving hormone therapy for hypothyroidism caused by Hashimoto's thyroiditis, she should schedule follow-up visits as often as her health care provider recommends. It's important to make sure she is receiving the correct dose of medicine. Over time, the dose she needs to adequately replace her thyroid function may change.
The only other caveat is that if your sister's symptoms persist despite medication and thyroid levels evening out, it is possible that the symptoms may be related to another underlying condition other than the thyroid.
Further evaluation for other potential causes of the symptoms is then warranted. Anemia, iron deficiency, obstructive sleep apnea, sleep disruptions, chronic pain, fibromyalgia, behavioral health concerns such as depression and anxiety, as well as significant stress have been found to be present in hypothyroid patients with appropriate thyroid levels and persistent symptoms. For the patient to feel better, these underlying issues need to be addressed. — Dr. Victor Bernet, Endocrinology, Diabetes and Metabolism, Mayo Clinic, Jacksonville, Florida
- Mayo Clinic Q and A: Hypothyroidism and dietary challenges published 9/14/20
- Mayo Clinic Q and A: Thyroid disorder may not show symptoms until pregnancy published 9/24/19
- Mayo Clinic Q and A: Mild hypothyroidism may not need treatment published 9/17/19
- Study finds similar cardiovascular outcomes for generic, brand-name drugs for hypothyroidism published 6/19/19