Normally, the thyroid produces two thyroid hormones: thyroxine (T4) and triioxothyronine (T3). These hormones are involved in several different functions of the body, including metabolism. Different conditions can cause the thyroid gland to not produce enough of these hormones; this condition is called hypothyroidism, or an underactive thyroid. Patients with an underactive thyroid can have several different symptoms, which vary due to the severity of the thyroid hormone deficiency.
Getting treatment for an underactive thyroid is important, as several complications from an untreated underactive thyroid are possible. Some of the complications are emergency conditions, such as myxedema coma and suppurative thyroiditis.
MedlinePlus noted that myxedema coma is the most severe type of hypothyroidism. Patients can develop myxedema coma if they have untreated hypothyroidism and are exposed to the cold or if they have an infection or illness.
Certain medications, such as lithium, sedatives and amiodarone, may also cause myxedema coma in patients with an untreated underactive thyroid. Symptoms include a slow heart rate, delirium, urine retention, constipation, seizures and fluid build-up.
Other symptoms include low blood sugar, low blood pressure, decreased breathing, a below normal temperature, stupor and coma. Myxedema coma is rare, but life-threatening. Of all cases, 30 to 60 percent of patients die, according to the University of Maryland Medical Center.
Suppurative thyroiditis, an infection of the thyroid gland, is also a rare and life-threatening complication of hypothyroidism. The condition usually begins with an upper respiratory infection.
Patients may have trouble speaking and swallowing, fever, rash and neck pain. The University of Maryland Medical Center noted that people with Hashimoto’s thyroiditis may have a higher risk.
Women with hypothyroidism face certain complications. The MayoClinic.com stated that a woman with untreated hypothyroidism have a higher risk of giving birth to a child with a birth defect, which can affect their intellect and development. The low levels of the thyroid hormones can also affect a woman’s ovulation, which may lead to infertility.
An infant with an underactive thyroid may have intellectual and developmental problems if the hypothyroidism is not treated. The University of Maryland Medical Center stated that when untreated, an infant can lose three to five IQ points every month during her first year of life. If a child over the age of two has hypothyroidism, possible complications include delay in new teeth and slowed physical growth.
Untreated hypothyroidism may affect a patient’s heart, as hypothyroidism patients tend to have high levels of low-density lipoprotein, or LDL, cholesterol, according to the MayoClinic.com. As a result, hypothyroidism may result in heart failure.
Several other complications may occur with untreated hypothyroidism. Depression and impaired mental functioning may occur.
Some patients may develop a goiter. Over time, hypothyroidism can damage the peripheral nerves, resulting in peripheral neuropathy, in which patients may have numbness, tingling or muscle weakness.
References
National Endocrine and Metabolic Diseases Information Service. Hypothyroidism. Web. 5 January 2012
http://endocrine.niddk.nih.gov/pubs/Hypothyroidism
MedlinePlus Medical Encyclopedia. Hypothyroidism. Web. 5 January 2012
http://www.nlm.nih.gov/medlineplus/ency/article/000353.htm
MayoClinic.com. Hypothyroidism: Complications. Web. 5 January 2012
http://www.mayoclinic.com/health/hypothyroidism/DS00353/DSECTION=complications
University of Maryland Medical Center. Hypothyroidism – Complications. Web. 5 January 2012
http://www.umm.edu/patiented/articles/who_gets_hypothyroidism_000038_5.htm
Reviewed January 6, 2012
by Michele Blacksberg RN
Edited by Jody Smith