Subclinical Thyroid Disease

Thyroid disease is a broad term used to describe any dysfunction of the thyroid gland. According to the National Institutes of Health, around 6 percent of Americans suffer from a type of thyroid disease. However, this number does not include those who have subclinical thyroid disease, a condition which occurs when an individual experiences symptoms of thyroid dysfunction yet has normal thyroid function test results.

The Thyroid

• The thyroid is a member of the endocrine system. It releases two hormones which help process energy, synthesize protein and regulate the stimulation of other hormones.

Thyroid Disease

• There are two main types of thyroid disease: hypothyroidism and hyperthyroidism. Hypothyroidism occurs when too little thyroid hormone is produced, causing metabolic and cardiac function to slow down. Hyperthyroidism occurs when there is too much thyroid hormone in the bloodstream, causing metabolism and cardiac function to speed up.

Symptoms of Thyroid Disease

• Hypothyroidism is characterized by weight gain, depression, slowed pulse, low body temperature and increased need for sleep. Symptoms of hyperthyroidism include racing heartbeat, insomnia, elevated mood, weight loss and intolerance to heat.

Subclinical Thyroid Disease

• An individual is considered to suffer from subclinical thyroid disease when they report symptoms of either hyperthyroidism or hypothyroidism while their blood tests for thyroid function remain in the range of normal function.

Controversy

• There is a growing consensus among health care professionals that thyroid disease is severely under diagnosed due to thyroid function test ranges which are too broad. Supporters of reference range reform point to the high number of subclinical thyroid cases as evidence, which researchers at the University of Florida Health Science Center have estimated include up to 20 percent of the population.