February 15, 2024 - Subclinical hypothyroidism and hypothyroidism share the same etiologies. Worldwide, iodine deficiency is the most common cause of hypothyroidism. However, autoimmune thyroiditis (Hashimoto thyroiditis) is the most common cause of hypothyroidism in the United States.

July 9, 2019 - This JAMA Patient Page describes subclinical hypothyroidism and its causes, symptoms, and treatment.

February 1, 2019 - In different studies, the prevalence ... cause of subclinical hypothyroidism, accounting for 60% to 80% of cases, is Hashimoto (autoimmune) thyroiditis,2 in which thyroid peroxidase antibodies are usually present.2,16...

August 9, 2023 - Elevated TSH levels in the absence of thyroid antibodies and goitre suggest subclinical hypothyroidism. The most common cause is autoimmune thyroiditis.

February 15, 1998 - Subclinical hypothyroidism is caused by the same disorders of the thyroid gland as those that cause overt hypothyroidism (Table 2).

Learn about subclinical (borderline) thyroid conditions

December 10, 2022 - Understand what happens when your thyroid is underactive and learn about treatment for this condition.

Hypothyroidism happens when your thyroid gland does not make enough thyroid hormone to meet your body's needs. Hypothyroidism is more common in women.

October 10, 2022 - Blunt force trauma or injury to the head or neck may reduce the thyroid’s ability to produce enough thyroid hormones to meet the body’s needs. This may lead to subclinical hypothyroidism. Radioactive iodine or antithyroid medications may cause subclinical hypothyroidism in people who have previously undergone treatment for hyperthyroidism.

June 28, 2024 - Causes include pituitary microadenoma and pituitary infarction. TSH elevation is important as a risk factor for cardiovascular disease. Patients with full hypothyroidism have serum levels of triglycerides, total cholesterol and low-density ...

September 10, 2016 - Subclinical thyroid disease occurs when the only lab abnormality is the thyroid-stimulating hormone (TSH) level as the thyroid hormone levels of T3 and T3 are normal. In subclinical hypothyroidism (underactive thyroid), a mild form of hypothyroidism, the TSH is slightly increased.

April 1, 2001 - Subclinical hypothyroidism is usually ... nonpalpable, or diffusely enlarged.12 The usual causes of subclinical hypothyroidism are thyroid autoimmunity and inadequately treated hypothyroidism....

October 21, 2025 - Here’s an example: because the adrenal hormone cortisol is needed to make T3, our most active thyroid hormone, a cortisol deficiency can cause hypothyroidism. But so can too MUCH cortisol from acute stress — it’s a delicate balancing act for the body.

June 5, 2024 - Secondary hypothyroidism is caused by hypothalamic or pituitary disease. Signs and symptoms of primary hypothyroidism are often mild and nonspecific and can include fatigue, cold intolerance, constipation, fluid retention, periorbital edema, and/or impaired mental clarity. Subclinical hypothyroidism (minimal or no symptoms and an elevated serum level of thyroid-stimulating hormone [TSH]) and normal free thyroxine [T4]) is common.

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May 15, 2021 - Diagnosis is based on blood levels of decreased FT4, with a corresponding elevated thyrotropin (i.e., TSH) level in primary causes (thyroid source); the TSH level may be normal to low in secondary (pituitary source) or tertiary (hypothalamic source) causes.5 Subclinical hypothyroidism describes the state of normal FT4 levels when the TSH level is elevated.

January 13, 2025 - It’s important to note that these symptoms can be due to other medical conditions. The most common cause of hypothyroidism is Hashimoto's disease — an autoimmune disorder that causes inflammation of the thyroid gland.

August 18, 2021 - The most common cause is autoimmune thyroid disease. Patients with a family history of autoimmune thyroid disease have a higher risk for developing subclinical and overt hypothyroidism. Subclinical hypothyroidism may occur after any form of thyroid injury such as following a partial thyroidectomy ...

Being an older woman (5% to 10% of women over age 50 have subclinical hypothyroidism and 2% women between age 70 and 80 years have overt hypothyroidism) ... Many permanent or temporary conditions can reduce thyroid hormone secretion and cause hypothyroidism. More than 90% of hypothyroidism cases occur from problems that start in the thyroid gland.

In the UK, the main cause of an underactive thyroid is an autoimmune condition called Hashimoto's disease.