Hyperthyroidism is characterized by increased thyroid hormone synthesis and secretion from the thyroid gland. Subclinical Hyperthyroidism is a mild form of hyperthyroidism that is defined by a low or undetectable serum thyroid-stimulating hormone (TSH) level, with normal free thyroxine (T4) and total or free triiodothyronine (T3) levels. The prevalence of hyperthyroidism in the US population is about 1.2% (0.5% overt and 0.7% subclinical). Subclinical hyperthyroidism is associated with impaired quality of life and hyperthyroid symptoms, as well as increased risk of bone loss and atrial fibrillation.
A study was undertaken in 2003 to understand management strategies at the time in the absence of clinical guidelines. A confidential clinical survey was mailed to 300 physician members in the American Thyroid Association (ATA) to assess their views on the management of subclinical hyperthyroidism using a variety of clinical scenarios. These scenarios included older vs. younger patients and those with mild vs. more severe subclinical hyperthyroidism as determined by the degree of TSH suppression. Respondents showed that they were more likely to recommend additional testing in patients with undetectable TSH values compared to patients with only slightly suppressed values. Additionally, antithyroid drugs were commonly prescribed as a treatment option amongst others such as Beta Blockers and surgery. In 2016, the ATA released guidelines for the diagnosis and management of subclinical hyperthyroidism. These guidelines presented additional treatment requirements and management options for patients with hyperthyroidism.
The central goal of this project is to repeat the prior clinical survey of ATA members to determine if the 2016 guidelines impacted clinical practice and to assess the practice patterns in general medicine providers. More specifically, to determine if any shift in treatment of subclinical hyperthyroidism was recorded among thyroid specialists and to compare practice patterns of Thyroid specialists to general practitioners.