Subclinical thyroid dysfunction: a joint statement on management from the American Association of Clinical Endocrinologists, the American Thyroid Association, and the Endocrine Society.

UBCLINICAL THYROID DYSFUNCTION is a common clinical problem for which there are many controversial issues regarding screening, evaluation, and management. Subclinical hypothyroidism is defined as an elevated serum thyroidstimulating hormone (TSH) level associated with normal total or free thyroxine (FT4) and free triiodothyronine (FT3) levels. The overall prevalence is 4% to 10% in the general population, and up to 20% in women older than 50 years (1‐3). Several alternative names have been proposed to describe this condition and include “compensated hypothyroidism,” “preclinical hypothyroidism,” “mild thyroid failure,” and “mild hypothyroidism.” While each term has subtle implications that may be more or less appropriate in various circumstances, we will use the term “subclinical hypothyroidism” in the interest of consistency with a recent publication that is the topic of this discussion. Subclinical hyperthyroidism is defined as low serum TSH levels associated with normal FT4 and FT3 levels. The prevalence is approximately 2%, being more common in women, in blacks, and in the elderly (4,5). In order to develop an evidence-based approach to the various unresolved clinical issues regarding subclinical thyroid disease, the American Association of Clinical Endocrinologists (AACE), the American Thyroid Association (ATA), and The Endocrine Society (TES) jointly sponsored a Consensus Development Conference, which was held in September 2002. A number of questions were presented to a panel of 13 experts, including 8 experts in thyroid disease; the remaining 5 had expertise in cardiology, epidemiology, biostatistics, evidence-based medicine, health-services research, general internal medicine, and clinical nutrition. The consensus panel report is the result of an extensive review of the published literature on these topics available at the time. The conference participants meticulously followed the principles of evidence-based medicine (EBM) to summarize all existing pertinent data (a summary of the data reviewed is available at www.endo-society.org/education/evidencereport.cfm) and to make EBM recommendations on the controversial issues of screening, evaluation, and management of patients with subclinical thyroid disease. The recently published consensus panel’s conclusions and recommendations (6) were developed independently and therefore did not require official review or approval by the three sponsoring societies. Recognizing the EBM methodology cannot adequately address gray areas where existing evidence is inadequate and that EBM-based guidelines cannot specifically address the multitude of variations encountered by clinicians in their management of individual patients, the consensus authors also published an accompanying case-based discussion illustrating how the guidelines could be applied in several patient scenarios (7). The authors of these two outstanding articles are to be congratulated for these excellent publications and thanked for their service to the community of providers who care for patients with thyroid disorders. Subsequently, having carefully studied the consensus conference data, summaries, and recommendations, the leadership of AACE, ATA, and TES determined that it would not be appropriate for practicing clinicians and the regulatory elements of the health care industry to be left with the impression that the membership of these three organizations unanimously agreed with all of the consensus conference recommendations, despite their sponsorship of the conference itself. They felt that the data in several areas were inconclusive and that further alternative interpretations and recommendations was not only reasonable but also warranted in the interest of academic fairness. Two members from each of these respective organizations were therefore invited to form a panel to review the consensus conference recommendations to determine if there were areas of legitimate and significant disagreement. All members of this panel