Estimates indicate that at least 3 percent of adult females in the United States receive treatment for hypothyroidism, an underactive thyroid gland, according to an article in the Oct. 9, 2007, edition of the journal "Circulation." Because subtle symptoms often go unnoticed, this likely represents a gross underestimation of the incidence of disease.
An underactive thyroid gland commonly requires a prescription of thyroid hormone to supplement the body's inadequate supply. If not enough thyroid hormone is taken, the patient continues to experience the symptoms of hypothryoidism.
Significance
Thyroid hormone controls metabolism through complex mechanisms involving interactions with other glands, hormones, cells and genes. With effects on nearly every major organ system, the importance of recognizing symptoms of an under-medicated thyroid cannot be overstated, as explained in the "Textbook of Internal Medicine."
While a doctor sees "signs" of disease through exams or laboratory tests, patients experience "symptoms," and these symptoms often bring the patient to medical attention.
General Well-Being
Because body systems and energy expenditure slow down in the hypothyroid state, patients generally feel sluggish. In fact, a symptom of ongoing or severe fatigue in patients taking thyroid hormone raises suspicion of under-treatment of the thyroid, states a review article in the December 2009 "Postgraduate Medical Journal." Patients feel weak and experience decreased tolerance for exercise, that when combined with decreased metabolism, contributes to weight gain. Depression could be another manifestation.
Gastrointestinal Effects
A comprehensive review article in the June 21, 2009, "World Journal of Gastroenterology" explains that all parts of the gastrointestinal, or GI, system suffer the effects of hypothyroidism. Constipation results from the slowing of the intestines and represents, by far, the most common GI symptom. Significant under-medication with thyroid hormone sometimes results in difficult or painful swallowing due to changes in how the esophagus, or food tube, works. When delayed emptying of the stomach occurs, patients often present with symptoms of nausea and heartburn as well as decreased appetite.
Other Common Symptoms
The "Postgraduate Medical Journal" review explains that the most sensitive indicators of under-treatment involve the skin. Dry, coarse skin with decreased sweating and intolerance to cold become bothersome. Hair turns coarse and brittle as well.
Goiters also frequently bring patients to medical attention as described on MayoClinic.com. When too little thyroid hormone circulates in the blood the pituitary gland secretes TSH--thyroid stimulating hormone--to tell the thyroid to make more thyroid hormone. When the thyroid is continuously bombarded with TSH, it enlarges from being overworked. This enlargement results in a goiter that shows up as a lump at the base of the neck. A goiter in a patient taking thyroid hormone pills reveals that treatment is likely inadequate.
Long-Term Consequences
Rarely, life-threatening problems occur from long-standing hypothyroidism. Patients who cannot or do not take their medication over an extended period of time risk enlargement of the heart and heart failure, which may present as a symptom of shortness of breath or chest tightness. Other symptoms of long-term hypothyroidism include slow speech, hair loss, possible deafness and problems with fertility, the "Postgraduate Medical Journal" article reveals.
References
- "Circulation"; Thyroid Disease and the Heart; Irwin Klein, MD and Sara Danzi, PhD.; 2007
- "Harrison's Textbook of Internal Medicine, 17th edition"; Anthony Fauci, Eugene Braunwald, et al, editors; 2009
- "The World Journal of Gastroenterology"; Consequences of Dysthyroidism on the Digestive Tract and Viscera; Daher, Ronald, et al; 2009
- "Postgraduate Medical Journal"; Management of Thryoid Disorders in Primary Care: Challenges and Controversies; C.H. Todd; 2009
- MayoClinic.com: Goiter, Causes
