AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS AND AMERICAN COLLEGE OF ENDOCRINOLOGY POSITION STATEMENT ON MENOPAUSE-2017 UPDATE.

EXECUTIVE SUMMARY This American Association of Clinical Endocrinologists (AACE)/American College of Endocrinology (ACE) Position Statement is designed to update the previous menopause clinical practice guidelines published in 2011 but does not replace them. The current document reviews new clinical trials published since then as well as new information regarding possible risks and benefits of therapies available for the treatment of menopausal symptoms. AACE reinforces the recommendations made in its previous guidelines and provides additional recommendations on the basis of new data. A summary regarding this position statement is listed below: New information available from randomized clinical trials and epidemiologic studies reported after 2011 was critically reviewed. No previous recommendations from the 2011 menopause clinical practice guidelines have been reversed or changed. Newer information enhances AACE's guidance for the use of hormone therapy in different subsets of women. Newer information helps to support the use of various types of estrogens, selective estrogen-receptor modulators (SERMs), and progesterone, as well as the route of delivery. Newer information supports the previous recommendation against the use of bioidentical hormones. The use of nonhormonal therapies for the symptomatic relief of menopausal symptoms is supported. Newer information enhances AACE's guidance for the use of hormone therapy in different subsets of women. Newer information helps to support the use of various types of estrogens, SERMs, and progesterone, as well as the route of delivery. Newer information supports the previous recommendation against the use of bioidentical hormones. The use of nonhormonal therapies for the symptomatic relief of menopausal symptoms is supported. New recommendations in this position statement include: 1. RECOMMENDATION: the use of menopausal hormone therapy in symptomatic postmenopausal women should be based on consideration of all risk factors for cardiovascular disease, age, and time from menopause. 2. RECOMMENDATION: the use of transdermal as compared with oral estrogen preparations may be considered less likely to produce thrombotic risk and perhaps the risk of stroke and coronary artery disease. 3. RECOMMENDATION: when the use of progesterone is necessary, micronized progesterone is considered the safer alternative. 4. RECOMMENDATION: in symptomatic menopausal women who are at significant risk from the use of hormone replacement therapy, the use of selective serotonin re-uptake inhibitors and possibly other nonhormonal agents may offer significant symptom relief. 5. RECOMMENDATION: AACE does not recommend use of bioidentical hormone therapy. 6. RECOMMENDATION: AACE fully supports the recommendations of the Comité de l'Évolution des Pratiques en Oncologie regarding the management of menopause in women with breast cancer. 7. RECOMMENDATION: HRT is not recommended for the prevention of diabetes. 8. RECOMMENDATION: In women with previously diagnosed diabetes, the use of HRT should be individualized, taking in to account age, metabolic, and cardiovascular risk factors. ABBREVIATIONS: AACE = American Association of Clinical Endocrinologists; ACE = American College of Endocrinology; BMI = body mass index; CAC = coronary artery calcification; CEE = conjugated equine estrogen; CEPO = Comité de l'Évolution des Pratiques en Oncologie; CAD = coronary artery disease; CIMT = carotid intima media thickness; CVD = cardiovascular disease; FDA = Food and Drug Administration; HDL = high-density lipoprotein; HRT = hormone replacement therapy; HT = hypertension; KEEPS = Kronos Early Estrogen Prevention Study; LDL = low-density lipoprotein; MBS = metabolic syndrome; MPA = medroxyprogesterone acetate; RR = relative risk; SERM = selective estrogen-receptor modulator; SSRI = selective serotonin re-uptake inhibitor; VTE = venous thrombo-embolism; WHI = Women's Health Initiative.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS, AMERICAN COLLEGE OF ENDOCRINOLOGY, AND ANDROGEN EXCESS AND PCOS SOCIETY DISEASE STATE CLINICAL REVIEW: GUIDE TO THE BEST PRACTICES IN THE EVALUATION AND TREATMENT OF POLYCYSTIC OVARY SYNDROME - PART 2.

Polycystic ovary syndrome (PCOS) is recognized as the most common endocrine disorder of reproductive-aged women around the world. This document, produced by the collaboration of the American Association of Clinical Endocrinologists and the Androgen Excess Society aims to highlight the most important clinical issues confronting physicians and their patients with PCOS. It is a summary of current best practices in 2014. Insulin resistance is believed to play an intrinsic role in the pathogenesis of PCOS. The mechanism by which insulin resistance or insulin give rise to oligomenorrhea and hyperandrogenemia, however, is unclear. Hyperinsulinemic-euglycemic clamp studies have shown that both obese and lean women with PCOS have some degree of insulin resistance. Insulin resistance is implicated in the ovulatory dysfunction of PCOS by disrupting the hypothalamic-pituitary-ovarian axis. Given the association with insulin resistance, all women with PCOS require evaluation for the risk of metabolic syndrome (MetS) and its components, including type 2 diabetes, hypertension, hyperlipidemia, and the possible risk of clinical events, including acute myocardial infarction and stroke. Obese women with PCOS are at increased risk for MetS with impaired glucose tolerance (IGT; 31 to 35%) and type 2 diabetes mellitus (T2DM; 7.5 to 10%). Rates of progression from normal glucose tolerance to IGT, and in turn to T2DM, may be as high as 5 to 15% within 3 years. Data suggest the need for baseline oral glucose tolerance test every 1 to 2 years based on family history of T2DM as well as body mass index (BMI) and yearly in women with IGT. Compared with BMI- and age-matched controls, young, lean PCOS women have lower high-density lipoprotein (HDL) size, higher very-low-density lipoprotein particle number, higher low-density lipoprotein (LDL) particle number, and borderline lower LDL size. Statins have been shown to lower testosterone levels either alone or in combination with oral contraceptives (OCPs) but have not shown improvement in menses, spontaneous ovulation, hirsutism, or acne. Statins reduce total and LDL cholesterol but have no effect on HDL, C-reactive protein, fasting insulin, or homeostasis model assessment of insulin resistance in PCOS women, in contrast to the general population. There have been no long-term studies of statins on clinical cardiac outcomes in women with PCOS. Coronary calcification is more prevalent and more severe in PCOS than in controls. In women under 60 years of age undergoing coronary angiography, the presence of polycystic ovaries on sonography has been associated with more arterial segments with >50% stenosis, but the relationship between PCOS and actual cardiovascular events remains unclear. Therapies for PCOS are varied in their effects and targets and include both nonpharmacologic as well as pharmacologic approaches. Weight loss is the primary therapy in PCOS--reduction in weight of as little as 5% can restore regular menses and improve response to ovulation- inducing and fertility medications. Metformin in premenopausal PCOS women has been associated with a reduction in features of MetS. Clamp studies using ethinyl estradiol/drosperinone combination failed to reveal evidence of an increase in either peripheral or hepatic insulin resistance. Subjects with PCOS have a 1.5-times higher baseline risk of venous thromboembolic disease and a 3.7-fold greater effect with OCP use compared with non-PCOS subjects. There is currently no genetic test to screen for or diagnose PCOS, and there is no test to assist in the choice of treatment strategies. Persistent bleeding should always be investigated for pregnancy and/or uterine pathology--including transvaginal ultrasound exam and endometrial biopsy--in women with PCOS. PCOS women can have difficulty conceiving. Those who become pregnant are at risk for gestational diabetes (which should be evaluated and managed appropriately) and the microvascular complications of diabetes. Assessment of a woman with PCOS for infertility involves evaluating for preconceptional issues that may affect response to therapy or lead to adverse pregnancy outcomes and evaluating the couple for other common infertility issues that may affect the choice of therapy, such as a semen analysis. Women with PCOS have multiple factors that may lead to an elevated risk of pregnancy, including a high prevalence of IGT--a clear risk factor for gestational diabetes--and MetS with hypertension, which increases the risk for pre-eclampsia and placental abruption. Women should be screened and treated for hypertension and diabetes prior to attempting conception. Women should be counseled about weight loss prior to attempting conception, although there are limited clinical trial data demonstrating a benefit to this recommendation. Treatment for women with PCOS and anovulatory infertility should begin with an oral agent such as clomiphene citrate or letrozole, an aromatase inhibitor.

AMERICAN ASSOCIATION OF CLINICAL ENDOCRINOLOGISTS, AMERICAN COLLEGE OF ENDOCRINOLOGY, AND ANDROGEN EXCESS AND PCOS SOCIETY DISEASE STATE CLINICAL REVIEW: GUIDE TO THE BEST PRACTICES IN THE EVALUATION AND TREATMENT OF POLYCYSTIC OVARY SYNDROME--PART 1.

Polycystic Ovary Syndrome (PCOS) is recognized as the most common endocrine disorder of reproductive-aged women around the world. This document, produced by the collaboration of the American Association of Clinical Endocrinologists (AACE) and the Androgen Excess and PCOS Society (AES) aims to highlight the most important clinical issues confronting physicians and their patients with PCOS. It is a summary of current best practices in 2015. PCOS has been defined using various criteria, including menstrual irregularity, hyperandrogenism, and polycystic ovary morphology (PCOM). General agreement exists among specialty society guidelines that the diagnosis of PCOS must be based on the presence of at least two of the following three criteria: chronic anovulation, hyperandrogenism (clinical or biological) and polycystic ovaries. There is need for careful clinical assessment of women's history, physical examination, and laboratory evaluation, emphasizing the accuracy and validity of the methodology used for both biochemical measurements and ovarian imaging. Free testosterone (T) levels are more sensitive than the measurement of total T for establishing the existence of androgen excess and should be ideally determined through equilibrium dialysis techniques. Value of measuring levels of androgens other than T in patients with PCOS is relatively low. New ultrasound machines allow diagnosis of PCOM in patients having at least 25 small follicles (2 to 9 mm) in the whole ovary. Ovarian size at 10 mL remains the threshold between normal and increased ovary size. Serum 17-hydroxyprogesterone and anti-Müllerian hormone are useful for determining a diagnosis of PCOS. Correct diagnosis of PCOS impacts on the likelihood of associated metabolic and cardiovascular risks and leads to appropriate intervention, depending upon the woman's age, reproductive status, and her own concerns. The management of women with PCOS should include reproductive function, as well as the care of hirsutism, alopecia, and acne. Cycle length >35 days suggests chronic anovulation, but cycle length slightly longer than normal (32 to 35 days) or slightly irregular (32 to 35-36 days) needs assessment for ovulatory dysfunction. Ovulatory dysfunction is associated with increased prevalence of endometrial hyperplasia and endometrial cancer, in addition to infertility. In PCOS, hirsutism develops gradually and intensifies with weight gain. In the neoplastic virilizing states, hirsutism is of rapid onset, usually associated with clitoromegaly and oligomenorrhea. Girls with severe acne or acne resistant to oral and topical agents, including isotretinoin (Accutane), may have a 40% likelihood of developing PCOS. Hair loss patterns are variable in women with hyperandrogenemia, typically the vertex, crown or diffuse pattern, whereas women with more severe hyperandrogenemia may see bitemporal hair loss and loss of the frontal hairline. Oral contraceptives (OCPs) can effectively lower androgens and block the effect of androgens via suppression of ovarian androgen production and by increasing sex hormone-binding globulin. Physiologic doses of dexamethasone or prednisone can directly lower adrenal androgen output. Anti-androgens can be used to block the effects of androgen in the pilosebaceous unit or in the hair follicle. Anti-androgen therapy works through competitive antagonism of the androgen receptor (spironolactone, cyproterone acetate, flutamide) or inhibition of 5α-reductase (finasteride) to prevent the conversion of T to its more potent form, 5α-dihydrotestosterone. The choice of antiandrogen therapy is guided by symptoms. The diagnosis of PCOS in adolescents is particularly challenging given significant age and developmental issues in this group. Management of infertility in women with PCOS requires an understanding of the pathophysiology of anovulation as well as currently available treatments. Many features of PCOS, including acne, menstrual irregularities, and hyperinsulinemia, are common in normal puberty. Menstrual irregularities with anovulatory cycles and varied cycle length are common due to the immaturity of the hypothalamic-pituitary-ovarian axis in the 2- to 3-year time period post-menarche. Persistent oligomenorrhea 2 to 3 years beyond menarche predicts ongoing menstrual irregularities and greater likelihood of underlying ovarian or adrenal dysfunction. In adolescent girls, large, multicystic ovaries are a common finding, so ultrasound is not a first-line investigation in women <17 years of age. Ovarian dysfunction in adolescents should be based on oligomenorrhea and/or biochemical evidence of oligo/anovulation, but there are major limitations to the sensitivity of T assays in ranges applicable to young girls. Metformin is commonly used in young girls and adolescents with PCOS as first-line monotherapy or in combination with OCPs and anti-androgen medications. In lean adolescent girls, a dose as low as 850 mg daily may be effective at reducing PCOS symptoms; in overweight and obese adolescents, dose escalation to 1.5 to 2.5 g daily is likely required. Anti-androgen therapy in adolescents could affect bone mass, although available short-term data suggest no effect on bone loss.

Cardiovascular and metabolic risks associated with PCOS.

Polycystic ovary syndrome, the most common endocrine disorder of reproductive age women, is often associated with insulin resistance and associated disorders. The frequency of type 2 diabetes, hyperlipidemia, cardiac risk markers, structural vascular disease, and clinical disease events are increased in this population of women. PCOS, however, represents a broad spectrum of clinical presentations, as defined by different criteria proposed in Europe and the United States. The role of insulin resistance and hence the risk of cardiometabolic disorders may in part be determined by the definition of PCOS used. Epidemiologic studies and clinical trials support the need to identify women with PCOS to determine their risk of cardiometabolic disorders to prevent and/or treat their serious consequences.

Clinical practice guidelines for hypothyroidism in adults: cosponsored by the American Association of Clinical Endocrinologists and the American Thyroid Association.

OBJECTIVE: Hypothyroidism has multiple etiologies and manifestations. Appropriate treatment requires an accurate diagnosis and is influenced by coexisting medical conditions. This paper describes evidence-based clinical guidelines for the clinical management of hypothyroidism in ambulatory patients. METHODS: The development of these guidelines was commissioned by the American Association of Clinical Endocrinologists (AACE) in association with American Thyroid Association (ATA). AACE and the ATA assembled a task force of expert clinicians who authored this article. The authors examined relevant literature and took an evidence-based medicine approach that incorporated their knowledge and experience to develop a series of specific recommendations and the rationale for these recommendations. The strength of the recommendations and the quality of evidence supporting each was rated according to the approach outlined in the American Association of Clinical Endocrinologists Protocol for Standardized Production of Clinical Guidelines-2010 update. RESULTS: Topics addressed include the etiology, epidemiology, clinical and laboratory evaluation, management, and consequences of hypothyroidism. Screening, treatment of subclinical hypothyroidism, pregnancy, and areas for future research are also covered. CONCLUSIONS: Fifty-two evidence-based recommendations and subrecommendations were developed to aid in the care of patients with hypothyroidism and to share what the authors believe is current, rational, and optimal medical practice for the diagnosis and care of hypothyroidism. A serum thyrotropin is the single best screening test for primary thyroid dysfunction for the vast majority of outpatient clinical situations. The standard treatment is replacement with L-thyroxine. The decision to treat subclinical hypothyroidism when the serum thyrotropin is less than 10 mIU/L should be tailored to the individual patient.

Clinical practice guidelines for hypothyroidism in adults: cosponsored by the American Association of Clinical Endocrinologists and the American Thyroid Association.

BACKGROUND: Hypothyroidism has multiple etiologies and manifestations. Appropriate treatment requires an accurate diagnosis and is influenced by coexisting medical conditions. This paper describes evidence-based clinical guidelines for the clinical management of hypothyroidism in ambulatory patients. METHODS: The development of these guidelines was commissioned by the American Association of Clinical Endocrinologists (AACE) in association with American Thyroid Association (ATA). AACE and the ATA assembled a task force of expert clinicians who authored this article. The authors examined relevant literature and took an evidence-based medicine approach that incorporated their knowledge and experience to develop a series of specific recommendations and the rationale for these recommendations. The strength of the recommendations and the quality of evidence supporting each was rated according to the approach outlined in the American Association of Clinical Endocrinologists Protocol for Standardized Production of Clinical Guidelines-2010 update. RESULTS: Topics addressed include the etiology, epidemiology, clinical and laboratory evaluation, management, and consequences of hypothyroidism. Screening, treatment of subclinical hypothyroidism, pregnancy, and areas for future research are also covered. CONCLUSIONS: Fifty-two evidence-based recommendations and subrecommendations were developed to aid in the care of patients with hypothyroidism and to share what the authors believe is current, rational, and optimal medical practice for the diagnosis and care of hypothyroidism. A serum thyrotropin is the single best screening test for primary thyroid dysfunction for the vast majority of outpatient clinical situations. The standard treatment is replacement with L-thyroxine. The decision to treat subclinical hypothyroidism when the serum thyrotropin is less than 10 mIU/L should be tailored to the individual patient.

Management of thyroid dysfunction during pregnancy and postpartum: an Endocrine Society clinical practice guideline.

OBJECTIVE: The aim was to update the guidelines for the management of thyroid dysfunction during pregnancy and postpartum published previously in 2007. A summary of changes between the 2007 and 2012 version is identified in the Supplemental Data (published on The Endocrine Society's Journals Online web site at http://jcem.endojournals.org). EVIDENCE: This evidence-based guideline was developed according to the U.S. Preventive Service Task Force, grading items level A, B, C, D, or I, on the basis of the strength of evidence and magnitude of net benefit (benefits minus harms) as well as the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system to describe both the strength of recommendations and the quality of evidence. CONSENSUS PROCESS: The guideline was developed through a series of e-mails, conference calls, and one face-to-face meeting. An initial draft was prepared by the Task Force, with the help of a medical writer, and reviewed and commented on by members of The Endocrine Society, Asia and Oceania Thyroid Association, and the Latin American Thyroid Society. A second draft was reviewed and approved by The Endocrine Society Council. At each stage of review, the Task Force received written comments and incorporated substantive changes. CONCLUSIONS: Practice guidelines are presented for diagnosis and treatment of patients with thyroid-related medical issues just before and during pregnancy and in the postpartum interval. These include evidence-based approaches to assessing the cause of the condition, treating it, and managing hypothyroidism, hyperthyroidism, gestational hyperthyroidism, thyroid autoimmunity, thyroid tumors, iodine nutrition, postpartum thyroiditis, and screening for thyroid disease. Indications and side effects of therapeutic agents used in treatment are also presented.

American Association of Clinical Endocrinologists Protocol for Standardized Production of Clinical Practice Guidelines--2010 update.

In 2004, the American Association of Clinical Endocrinologists (AACE) published the "Protocol for Standardized Production of Clinical Practice Guidelines," which was to be implemented in forthcoming clinical practice guidelines (CPG). This protocol formally incorporated subjective factors and evidence-based medicine (EBM) methods that tightly mapped evidence levels to recommendation grades. A uniform publication template and multilevel review process were also outlined. Seven CPG have been subsequently published with use of this 2004 AACE protocol. Recently, growing concerns about the usefulness of CPG have been raised. The purposes of this report are to address shortcomings of the 2004 AACE protocol and to present an updated 2010 AACE protocol for CPG development. AACE CPG are developed without any industry involvement. Multiplicities of interests among writers and reviewers that might compromise the usefulness of CPG are avoided. Three major goals are to (1) balance transparently the effect of rigid quantitative EBM methods with subjective factors, (2) create a less onerous, less time-consuming, and less costly CPG production process, and (3) introduce an electronic implementation component. The updated 2010 AACE protocol emphasizes "informed judgment" and hybridizes EBM descriptors (study design type), qualifiers (study flaws), and subjective factors (such as risk, cost, and relevance). In addition, by focusing on more specific topics and clinical questions, the expert evaluation and multilevel review process is more transparent and expeditious. Lastly, the final recommendations are linked to a new electronic implementation feature.

Management of thyroid dysfunction during pregnancy and postpartum: an Endocrine Society Clinical Practice Guideline.

OBJECTIVE: The objective is to provide clinical guidelines for the management of thyroid problems present during pregnancy and in the postpartum. PARTICIPANTS: The Chair was selected by the Clinical Guidelines Subcommittee (CGS) of The Endocrine Society. The Chair requested participation by the Latin American Thyroid Society, the Asia and Oceania Thyroid Society, the American Thyroid Association, the European Thyroid Association, and the American Association of Clinical Endocrinologists, and each organization appointed a member to the task force. Two members of The Endocrine Society were also asked to participate. The group worked on the guidelines for 2 yr and held two meetings. There was no corporate funding, and no members received remuneration. EVIDENCE: Applicable published and peer-reviewed literature of the last two decades was reviewed, with a concentration on original investigations. The grading of evidence was done using the United States Preventive Services Task Force system and, where possible, the GRADE system. CONSENSUS PROCESS: Consensus was achieved through conference calls, two group meetings, and exchange of many drafts by E-mail. The manuscript was reviewed concurrently by the Society's CGS, Clinical Affairs Committee, members of The Endocrine Society, and members of each of the collaborating societies. Many valuable suggestions were received and incorporated into the final document. Each of the societies endorsed the guidelines. CONCLUSIONS: Management of thyroid diseases during pregnancy requires special considerations because pregnancy induces major changes in thyroid function, and maternal thyroid disease can have adverse effects on the pregnancy and the fetus. Care requires coordination among several healthcare professionals. Avoiding maternal (and fetal) hypothyroidism is of major importance because of potential damage to fetal neural development, an increased incidence of miscarriage, and preterm delivery. Maternal hyperthyroidism and its treatment may be accompanied by coincident problems in fetal thyroid function. Autoimmune thyroid disease is associated with both increased rates of miscarriage, for which the appropriate medical response is uncertain at this time, and postpartum thyroiditis. Fine-needle aspiration cytology should be performed for dominant thyroid nodules discovered in pregnancy. Radioactive isotopes must be avoided during pregnancy and lactation. Universal screening of pregnant women for thyroid disease is not yet supported by adequate studies, but case finding targeted to specific groups of patients who are at increased risk is strongly supported.

Polycystic ovarian syndrome and insulin resistance: implications for estrogen use in premenopausal and postmenopausal women.

Polycystic ovarian syndrome (PCOS) is the most frequent endocrine disorder of reproductive age women, affecting an estimated 8-10% of all women in this age group or approximately six million women. Further, women with PCOS continue to manifest the metabolic alterations inherent in the insulin resistance syndrome after menopause, rendering them more susceptible to type 2 diabetes and cardiovascular disease. Aging and obesity further contribute to these risks. Since estrogen-containing therapy is commonly used for menstrual regulation in premenopausal women with PCOS, it is important to evaluate the possible consequences of hormonal therapy on subsequent metabolic and cardiovascular risk. In postmenopausal women, a consensus regarding the appropriate role of estrogen replacement therapy is currently in evolution. By examining the effects of estrogen with or without progesterone on insulin resistance, insight may be gained about the risk/benefit ratio of this therapy in the subset of women with insulin resistance, PCOS, and type 2 diabetes. The goal of this review, then, is to examine the known effects of estrogen on insulin sensitivity and its implications for cardiovascular and metabolic risk.

Subclinical thyroid disease: scientific review and guidelines for diagnosis and management.

CONTEXT: Patients with serum thyroid-stimulating hormone (TSH) levels outside the reference range and levels of free thyroxine (FT4) and triiodothyronine (T3) within the reference range are common in clinical practice. The necessity for further evaluation, possible treatment, and the urgency of treatment have not been clearly established. OBJECTIVES: To define subclinical thyroid disease, review its epidemiology, recommend an appropriate evaluation, explore the risks and benefits of treatment and consequences of nontreatment, and determine whether population-based screening is warranted. DATA SOURCES: MEDLINE, EMBASE, Biosis, the Agency for Healthcare Research and Quality, National Guideline Clearing House, the Cochrane Database of Systematic Reviews and Controlled Trials Register, and several National Health Services (UK) databases were searched for articles on subclinical thyroid disease published between 1995 and 2002. Articles published before 1995 were recommended by expert consultants. STUDY SELECTION AND DATA EXTRACTION: A total of 195 English-language or translated papers were reviewed. Editorials, individual case studies, studies enrolling fewer than 10 patients, and nonsystematic reviews were excluded. Information related to authorship, year of publication, number of subjects, study design, and results were extracted and formed the basis for an evidence report, consisting of tables and summaries of each subject area. DATA SYNTHESIS: The strength of the evidence that untreated subclinical thyroid disease is associated with clinical symptoms and adverse clinical outcomes was assessed and recommendations for clinical practice developed. Data relating the progression of subclinical to overt hypothyroidism were rated as good, but data relating treatment to prevention of progression were inadequate to determine a treatment benefit. Data relating a serum TSH level higher than 10 mIU/L to elevations in serum cholesterol were rated as fair but data relating to benefits of treatment were rated as insufficient. All other associations of symptoms and benefit of treatment were rated as insufficient or absent. Data relating a serum TSH concentration lower than 0.1 mIU/L to the presence of atrial fibrillation and progression to overt hyperthyroidism were rated as good, but no data supported treatment to prevent these outcomes. Data relating restoration of the TSH level to within the reference range with improvements in bone mineral density were rated as fair. Data addressing all other associations of subclinical hyperthyroid disease and adverse clinical outcomes or treatment benefits were rated as insufficient or absent. Subclinical hypothyroid disease in pregnancy is a special case and aggressive case finding and treatment in pregnant women can be justified. CONCLUSIONS: Data supporting associations of subclinical thyroid disease with symptoms or adverse clinical outcomes or benefits of treatment are few. The consequences of subclinical thyroid disease (serum TSH 0.1-0.45 mIU/L or 4.5-10.0 mIU/L) are minimal and we recommend against routine treatment of patients with TSH levels in these ranges. There is insufficient evidence to support population-based screening. Aggressive case finding is appropriate in pregnant women, women older than 60 years, and others at high risk for thyroid dysfunction.