Incidence of hyperthyroidism in Stockholm, Sweden, 2003-2005

Thyroid Disorders

This article includes a review of information primary care physicians need to know direct their evaluation and treatment of thyroid disorders that include sick euthyroid, hyperthyroidism, hypothyroidism, and subclinical thyroid disorders.

Long-Term Outcome of Graves' Disease: A Gender Perspective

Introduction

In gender-skewed conditions such as Graves' disease (GD), the outcome naturally becomes dominated by the majority. This may lead to gender-biased misunderstandings regarding treatment outcomes. This especially holds true when complications, such as depression, are unevenly distributed. We have, therefore, studied the long-term outcome of GD from a gender perspective.

Materials and Methods

A cohort of 1186 patients with GD was included in a follow-up 6-10 years after inclusion. Choice of treatment, the feeling of recovery, long-term treatment, comorbidity, and quality of life were investigated with questionnaires. All results were studied sex-divided.

Results

We included 973 women and 213 men. There was no difference between men and women in the choice of treatment. At follow-up, women scored significantly worse in the general questionnaire 36-item Short-Form Health Status (SF-36) domain bodily pain and in the thyroid-specific Thyroid-Related Patient-Reported Outcome (ThyPRO) domains depression, impaired sex life, and cosmetic complaints, all p < 0.05. Women were twice as likely (29.5%) to be treated with levothyroxine after successful treatment with antithyroid drugs (ATD) compared with men (14.9%, p < 0.05).

Conclusion

After treatment for GD, women were more affected by depression, impaired sex life, cosmetic issues, and bodily pain despite successful cure of hyperthyroidism. The prevalence of hypothyroidism was also doubled in women. Whether these observed gender differences reflect a worse outcome of GD in women or a natural consequence of a higher prevalence of these symptoms and autoimmunity in the female population is difficult to disentangle. Nevertheless, several years after GD, women reveal more persistent symptoms.

Update on the surgical management of Graves' orbitopathy

Graves' orbitopathy (GO) is a complex autoimmune disorder of the orbit that causes the eye to appear disfigured. GO is typically associated with Graves' disease, an inflammatory autoimmune condition that is caused by thyrotropin receptor autoantibodies. Although our knowledge of the pathophysiology of GO has improved, its exact pathogenesis remains unclear. Some patients suffer from disfigurement, double vision, and even vision loss rather than hyperthyroidism. The disease severity and activity prompt different treatments, as the signs of GO are heterogeneous, so their management can be very complex. Despite medical advances, the first-line treatment for moderate-to-severe active GO is still glucocorticoids, while surgery can be critical for the treatment of chronic inactive GO. Surgery is sometimes required in the acute phase of the disease when there is an immediate risk to vision, such as in dysthyroid optic neuropathy. Most surgeries for GO are rehabilitative and subdivided into three categories: decompression, strabismus repair, and lid surgery. This review is a basic overview of the field, with up-to-date knowledge of the surgical techniques for GO. We review and summarize recent literature on the advances in surgery for GO to provide up-to-date insights on the optimal surgical treatment for GO.

Revision orbital decompression for thyroid eye disease

OBJECTIVE

To compare the indications, surgical techniques and outcomes for revision orbital decompression surgery for thyroid eye disease in open, endoscopic, and combined open and endoscopic approaches.

METHODS

A retrospective review of all revision orbital decompression procedures for thyroid eye disease from a single large academic institution over a 17-year period (01/01/2004-01/01/2021) was performed. Patient demographics, as well as indications and types of surgery were reviewed. Outcome measures included changes in proptosis, intraocular pressure, visual acuity and diplopia.

RESULTS

Thirty procedures were performed on 21 patients. There was a median of 9.4 months between primary orbital decompression and revision decompression surgery. There were 6 bilateral procedures, and 2 of these patients underwent additional revision surgeries due to decreased visual acuity with concern for persistent orbital apex compression or sight-threatening ocular surface exposure in the setting of proptosis. Twenty-five procedures were performed as open surgeries with 5 endoscopic/combined cases. Combined Ophthalmology/Otolaryngology surgery via combined open/endoscopic approaches was favoured for persistent orbital apex disease. Visual acuity remained preserved in all patients. The overall median reduction in proptosis was 2 mm and intraocular pressure change was 1 mmHg regardless of surgical approach. The overall rate of new onset diplopia after surgery was 15%. These patients had open approaches. All endoscopic/combined approach patients had pre-existing diplopia. There were no statistically significant differences between the open and endoscopic/combined groups in regard to change in visual acuity, reduction in proptosis or intraocular pressure.

CONCLUSION

Revision orbital decompression is an uncommon procedure indicated for those patients with progressive symptoms despite previous surgery and intensive medical management. Both endoscopic and non-endoscopic techniques offer favourable outcomes with respect to visual acuity, decrease in intraocular pressure, and improvement in proptosis and overall lead to a low incidence of new onset diplopia.

LEVEL OF EVIDENCE

Level IV.

Impaired Quality of Life After Radioiodine Therapy Compared to Antithyroid Drugs or Surgical Treatment for Graves' Hyperthyroidism: A Long-Term Follow-Up with the Thyroid-Related Patient-Reported Outcome Questionnaire and 36-Item Short Form Health Status Survey

BACKGROUND

Hyperthyroidism is known to have a significant impact on quality of life (QoL), at least in the short term. The purpose of the present study was to assess QoL in patients 6-10 years after treatment for Graves' disease (GD) with radioiodine (RAI) compared to those treated with thyroidectomy or antithyroid drugs (ATD) as assessed with both thyroid-specific Thyroid-Related Patient-Reported Outcome (ThyPRO) questionnaire and general (36-item Short Form Health Status) QoL survey.

METHODS

The study evaluated 1186 GD patients in a sub-cohort from an incidence study 2003-2005 who had been treated according to routine clinical practice at seven participating centers. Patients were included if they had returned the ThyPRO (n = 975) and/or the 36-item Short Form Health Status survey questionnaire (n = 964) and informed consent at follow-up. Scores from ThyPRO were compared to scores from a general population sample (n = 712) using multiple linear regression adjusting for age and sex as well as multiple testing. Treatment-related QoL outcome for ATD, RAI, and surgery were compared, including adjustment for the number of treatments received, sex, age, and comorbidity.

RESULTS

Regardless of treatment modality, patients with GD had worse thyroid-related QoL 6-10 years after diagnosis compared to the general population. Patients treated with RAI had worse thyroid-related and general QoL than patients treated with ATD or thyroidectomy on the majority of QoL scales. Sensitivity analyses supported the relative negative comparative effects of RAI treatment on QoL in patients with hyperthyroidism.

CONCLUSIONS

GD is associated with a lower QoL many years after treatment compared to the general population. In a previous small randomized controlled trial, no difference was found in patient satisfaction years after ATD, RAI, or surgery. Now, it is reported that in a large non-randomized cohort, patients who received RAI had adverse scores on ThyPRO and 36-item Short Form Health Status survey. These findings in a Swedish population are limited by comparison to normative data from Denmark, older age, and possibly a more prolonged course in those patients who received RAI, and a lack of information regarding thyroid status at the time of evaluation. The way RAI may adversely affect QoL is unknown, but since the results may be important for future considerations regarding treatment options for GD, they need to be substantiated in further studies.

Establishment of a tear protein biomarker panel differentiating between Graves' disease with or without orbitopathy

Background

Graves’ orbitopathy (GO) is an autoimmune inflammatory ocular complication and one of the most frequent manifestations of Graves’ disease (GD). Clinical judgment of GO is subjective sometimes leading to clinical and therapeutic challenges. Better tools to diagnose this severe complication are warranted.

Patients and methods

The aim of the present study was to evaluate tear levels of LYZ, LACRT and AZGP1 in GD patients with or without GO, as possible biomarkers for GO. Tear samples were collected from GD patients with moderate-to-severe GO (n = 21) and no clinical signs of GO (n = 21). Additionally, 18 GD patients with mild GO and 9 patients without GO were included in a further part of the study.

Results

Tear levels of LYZ (p < 0.001), LACRT (p = 0.004) and AZGP1 (p = 0.001) were significantly elevated in GD patients with moderate-to-severe GO compared to GD patients without GO. The discriminatory power of the three biomarkers, combined in a panel was confirmed by ROC plot analysis, with an AUC value of 0.93 (sensitivity of 95%; specificity of 80%). Since LYZ showed the best performance in discriminating between GD patients with (moderate-to-severe) and without GO (in combination with limited sample volume available), LYZ levels were also measured in tears from GD patients with mild GO and without GO. Significantly higher levels of LYZ were measured in GD patients with mild GO compared to those without GO (p = 0.003).

Conclusions

We have established a novel three-protein biomarker panel that is able to discriminate between GD patients with and without GO, which might aid in diagnostic evaluation of GO as well as an indicator for disease activity.

Thyroid Dysfunction in Primary Biliary Cholangitis: A Comparative Study at Two European Centers

OBJECTIVES

Primary biliary cholangitis (PBC) is often associated with other autoimmune diseases, but little is known about the influence of thyroid disease (TD) on the natural history of PBC. Our aim is to analyze the association between PBC and TD, and the latter's impact on the natural history of PBC at two European centers.

METHODS

The study involved 921 PBC patients enrolled between 1975 and 2015 in Padova (376 patients) and Barcelona (545 patients), with a mean follow-up of 126.9±91.7 months. Data were recorded on patients' histological stage at diagnosis, biochemical data, associated extrahepatic autoimmune conditions, and clinical events, including hepatic decompensation.

RESULTS

A total of 150 patients (16.3%) had TD, including 94 patients (10.2%) with Hashimoto's thyroiditis; 15 (1.6%) with Graves' disease; 22 (2.4%) with multinodular goiter; 7 (0.8%) with thyroid cancer; and 12 (1.3%) with other thyroid conditions. The prevalence of different types of TD was similar in Padova and Barcelona, except for Graves' disease and thyroid cancer, which were more frequent in the Padova cohort (15.7 vs. 5.0%, and 8.6 vs. 1.3%, respectively, P<0.05). Overall, there were no differences between PBC patients with and without TD in terms of their histological stage at diagnosis, hepatic decompensation events, occurrence of HCC, or liver transplantation rate. The presence of associated TD was not associated with lower survival for PBC patients in either cohort.

CONCLUSIONS

TDs, and autoimmune TD like Hashimoto's thyroiditis in particular, are often associated with PBC, but the presence of TD does not influence the rate of hepatic complications or the natural history of PBC.

Safety of AS03-adjuvanted inactivated split virion A(H1N1)pdm09 and H5N1 influenza virus vaccines administered to adults: pooled analysis of 28 clinical trials

Clinical trials have shown that AS03-adjuvanted H5N1 and A(H1N1)pdm09 vaccines are highly immunogenic, although with an increased reactogenicity profile relative to non-adjuvanted vaccines in terms of the incidence of common injection site and systemic adverse events (AEs). We evaluated pooled safety data from 22,521 adults who had received an AS03-adjuvanted H5N1 or A(H1N1)pdm09 influenza or control vaccine with the purpose to identify medically-attended AEs (MAEs), including subsets of serious AEs (SAEs), potentially immune-mediated diseases (pIMDs), and AEs of special interest (AESI), and to explore a potential association of these AEs with the administration of an AS03-adjuvanted influenza vaccine. For participants who had received an AS03-adjuvanted vaccine, the relative risks (RRs) for experiencing a MAE or a SAE compared to control group (participants who had received a non-adjuvanted vaccine or saline placebo) were 1.0 (95% confidence interval [CI]: 0.9; 1.1) and 1.1 (95% CI: 0.9; 1.4), respectively. The overall RRs for experiencing an AESI or a pIMD (AS03-adjuvanted vaccine/control) were 1.2 (95% CI: 0.9; 1.6) and 1.7 (95% CI: 0.8; 3.8), respectively. Thirty-8 participants in the AS03-adjuvanted vaccine group had a pIMD reported after vaccine administration, yielding an incidence rate (IR) of 351.9 (95% CI: 249.1; 483.1) per 100,000 person-years. The estimated IRs in the AS03-adjuvanted vaccine group were greater than the literature reported rates for: facial paresis/VIIth nerve paralysis, celiac disease, thrombocytopenia and ulcerative colitis. These results do not support an association between AS03-adjuvanted H5N1 and A(H1N1)pdm09 vaccines and the AEs collected in the trials included in the analysis.

Pediatric Graves' disease: management in the post-propylthiouracil Era

The most prevalent cause of thyrotoxicosis in children is Graves’ disease (GD), and remission occurs only in a modest proportion of patients. Thus most pediatric patients with GD will need treatment with radioactive iodine (RAI; ¹³¹I) or surgical thyroidectomy. When antithyroid drugs (ATDs) are prescribed, only methimazole (MMI) should be administered, as PTU is associated with an unacceptable risk of severe liver injury. If remission does not occur following ATD therapy, ¹³¹I or surgery should be contemplated. When ¹³¹I is administered, dosages should be greater than 150 uCi/gm of thyroid tissue, with higher dosages needed for large glands. Considering that there will be low-level whole body radiation exposure associated with ¹³¹I, this treatment should be avoided in young children. When surgery is performed near total or total-thyroidectomy is the recommended procedure. Complications for thyroidectomy in children are considerably higher than in adults, thus an experienced thyroid surgeon is needed when children are operated on. Most importantly, the care of children with GD can be complicated and requires physicians with expertise in the area.

Long-term prognosis after medical treatment of Graves' disease in a northern Swedish population 2000-2010

OBJECTIVE

To investigate the long-term prognosis of patients with Graves' disease (GD) after antithyroid drug (ATD) treatment and follow-up outside of highly specialised care.

DESIGN AND METHODS

Medical records of all patients diagnosed with first-time GD in 2000-2010 with at least 6 months ATD treatment at a central hospital and follow-up in primary health care in the county of Norrbotten in northern Sweden were retrospectively reviewed. Patients were followed for relapse until 31st December 2012. We included 219 patients (mean age 46 years, 82.5% women) with follow-up of maximum 10 years and 829 observed patient years. Data were analysed using Kaplan-Meier estimates and log-rank test.

RESULTS

During the observation period, 43.5% of the patients had relapsed into active GD. The cumulative relapse rates were 22.6, 30.2, 36.9 and 41.5% after 6 months, 1, 3 and 5 years respectively. The presence of goitre (P=0.014) predicted relapse. Previous smoking was protective against relapse (P=0.003). The levels of free thyroxine or free tri-iodothyronine, age, gender, current smoking and ophthalmopathy did not predict relapse. Agranulocytosis was found in 1.7% (95% CI 0.7-4.0%).

CONCLUSION

A long-term remission of 56.5%, in an iodine-sufficient area where ATD is offered to most patients in the real world of central and district hospitals, is higher than in most studies. Relapse was most common during the first year, and prognosis was excellent after 4 years without relapse. The protective effect of previous smoking merits further research.

Graves' ophthalmopathy: epidemiology and natural history

Graves' ophthalmopathy (GO) is an autoimmune disorder of the orbit that is clinically relevant in 25-50% of patients with Graves' disease and 2% of patients with chronic thyroiditis. The age-adjusted annual incidence of clinically relevant GO is 16 per 100,000 population in women and 2.9 in men. At the onset of ophthalmopathy, 80-90% of patients have hyperthyroidism, with the rest having euthyroidism or hypothyroidism. The natural history of GO consists of two phases: an active inflammatory phase and a static phase. Anti-inflammatory therapy is indicated for the first phase of GO. Approximately 5% of patients experience late reactivation of GO. Asians appear to have less severe manifestations, with milder orbital edema, proptosis and muscle restriction. Genetic, anatomic and environmental factors influence the development of GO. Aging, thyroid dysfunction, thyroid stimulating hormone (TSH) receptor antibodies, smoking and radioiodine treatment for hyperthyroidism also influence the development and course of GO.

Incidence rate and clinical features of hyperthyroidism in a long-term iodine sufficient area of Sweden (Gothenburg) 2003-2005

OBJECTIVES

To study hyperthyroidism in long-term iodine sufficiency (IS), as iodine supply affects its occurrence.

DESIGN

Prospective descriptive study.

PATIENTS

In 2003-2005, all referred cases of subclinical (SH) and overt hyperthyroidism (OH) were registered at diagnosis from a population (n = 631 239) in Gothenburg, Sweden.

MEASUREMENTS

Information on age, gender, smoking, thyroid associated ophthalmopathy (TAO), thyroid hormones and TSH receptor antibodies (TRab) was collected. Incidences were calculated. SH and OH cases with Graves' disease (GD), toxic multinodular goiter (TMNG) and solitary toxic adenoma (STA) were compared. In GD, TRab+ and TRab- cases and patients with (TAO+) and without TAO (TAO-) were compared.

RESULTS

The total incidence (n/100 000/year) of hyperthyroidism was 27·6; OH 23·8; SH 3·8; GD 21·4; TMNG 4·3; and STA 1·8. SH was more common among TMNG (40·2%) and STA (45·7%) than in GD (5·9%). SH-GD patients were older, more often smokers and had lower TRab levels than OH-GD patients. FreeT4 and T3 levels in GD were higher than in TMNG and STA. FreeT4, T3 and TRab decreased with age in patients with GD, P < 0·0001. TRab- patients had lower T3 than TRab+ patients, P < 0·001. TRab was positively correlated to FreeT4, P < 0·0001. TAO occurred in 20% of patients with GD. TAO+ patients were younger than TAO- patients. Smokers did not have more TAO.

CONCLUSION

The total incidence of hyperthyroidism was low. GD dominated with an age-related decline of thyroid hormones and TRab levels. The spectrum of hyperthyroidism in this long-term IS area may represent the future situation for countries with shorter history of IS.

Thyroid dysfunction in the elderly

Thyroid dysfunction is common in the general population, and mild or subclinical forms can be present in more than 10% of individuals aged >80 years. The diagnosis of abnormal thyroid hormone concentrations in people aged >60 years poses a challenge, as the clinical presentation of thyroid dysfunction is usually nonspecific, and ageing is associated with a number of physiological changes that can affect thyroid function test results. Furthermore, the presence of acute or chronic nonthyroidal illnesses and the use of medications that interfere with thyroid function tests are common confounders in the determination of thyroid status in the elderly. Early diagnosis and treatment of overt thyroid dysfunction is crucial in this population in view of the marked effects of abnormal circulating thyroid hormone levels on a number of organ systems, including the heart, the skeleton and the neurological system. The clinical significance of mild thyroid overactivity and underactivity remains uncertain, and the need for treatment of subclinical thyroid dysfunction is much debated. A number of large epidemiological studies have identified associations between mild thyroid dysfunction and short-term as well as long-term adverse outcomes, and a small but increasing number of randomized controlled intervention studies have been reported. Guidelines recommend treatment of thyroid dysfunction on the basis of the degree of abnormal serum TSH concentrations, patient age and associated comorbidities. This Review describes the current evidence on the prevalence, diagnosis, management and long-term consequences of thyroid dysfunction in the elderly.

Subclinical thyroid disease

INTRODUCTION

Subclinical thyroid disease is a common finding on testing of thyroid function and its management remains controversial.

SOURCE OF DATA

Epidemiological data from large population studies from USA and Europe.

AREAS OF AGREEMENT

There is an increased risk of progression to overt hypothyroidism or hyperthyroidism. The treatment of mild thyroid failure is of importance in optimizing pregnancy outcome.

AREAS OF CONTROVERSY

Diagnostic criteria differ and there is variation between management guidelines. The difference was found in long-term clinical outcomes between endogenous and exogenous subclinical hyperthyroidism.

GROWING POINTS

Meta-analyses have provided epidemiological data in cardiovascular mortality and morbidity in subclinical thyroid disease. Increased use of echocardiography and bone markers in identifying those who benefit from intervention.

AREAS TIMELY FOR DEVELOPING RESEARCH

A randomized controlled trial to identify those subjects identified from screening programmes that benefit from intervention in terms of morbidity and mortality.

The incidence and prevalence of thyroid autoimmunity

The thyroid gland is the most common organ affected by autoimmune disease. Other autoimmune diseases, most notably type 1 diabetes mellitus, are increasing in incidence. It is unknown whether autoimmune thyroid diseases are following the same pattern. This review summarizes studies of autoimmune thyroid disease incidence and prevalence since 1950, not only for these measures of occurrences, but also for commenting on identified risk factors for thyroid autoimmunity. We find that incidence of autoimmune thyroid disease is currently higher than in historic series although the studies are so variable in design, patient population, disease definition, and laboratory methods that it is impossible to tell whether this difference is real. Further research is required to assess the possibility of changing disease patterns of autoimmune thyroid disease as opposed to simple changes in diagnostic thresholds.

Epidemiology of Graves' orbitopathy (GO) and relationship with thyroid disease

The incidence of Graves' orbitopathy (GO) is 16/100,000 in females and 2.9/100,000 in males as studied in Olmsted county. It can be calculated that the approximate prevalence is 0.25%. There is a gender bimodal distribution. Go usually occurs at the time of onset of the hyperthyroidism but may present up to a year before that time or as long as 5 years afterwards. Around 10-15% of patients have never been hyperthyroid and some are hypothyroid at GO presentation. Although the incidence of GO has probably been decreasing during the last 2 decades definite figures for this assertion are not available. Risk factors that may influence the incidence of GO include cigarette smoking and radioiodine treatment of hyperthyroidism. There are also complex genetic factors with multiple susceptibility alleles that contribute to the expression of the disease. The probability is that a reduction of the incidence of GO will be achieved by influencing the environmental factors.

Subclinical thyroid disease

Subclinical thyroid diseases--subclinical hyperthyroidism and subclinical hypothyroidism--are common clinical entities that encompass mild degrees of thyroid dysfunction. The clinical significance of mild thyroid overactivity and underactivity is uncertain, which has led to controversy over the appropriateness of diagnostic testing and possible treatment. In this Seminar, we discuss the definition, epidemiology, differential diagnoses, risks of progression to overt thyroid disease, potential effects on various health outcomes, and management of subclinical hyperthyroidism and subclinical hypothyroidism. Treatment recommendations are based on the degree to which thyroid-stimulating hormone concentrations have deviated from normal and underlying comorbidities. Large-scale randomised trials are urgently needed to inform how to best care for individuals with subclinical thyroid disease.

Incidence of hyperthyroidism in Sweden

INTRODUCTION

The incidence of hyperthyroidism has been reported in various countries to be 23-93/100,000 inhabitants per year. This extended study has evaluated the incidence for ~40% of the Swedish population of 9 million inhabitants. Sweden is considered to be iodine sufficient country.

METHODS

All patients including children, who were newly diagnosed with overt hyperthyroidism in the years 2003-2005, were prospectively registered in a multicenter study. The inclusion criteria are as follows: clinical symptoms and/or signs of hyperthyroidism with plasma TSH concentration below 0.2 mIE/l and increased plasma levels of free/total triiodothyronine and/or free/total thyroxine. Patients with relapse of hyperthyroidism or thyroiditis were not included. The diagnosis of Graves' disease (GD), toxic multinodular goiter (TMNG) and solitary toxic adenoma (STA), smoking, initial treatment, occurrence of thyroid-associated eye symptoms/signs, and demographic data were registered.

RESULTS

A total of 2916 patients were diagnosed with de novo hyperthyroidism showing the total incidence of 27.6/100,000 inhabitants per year. The incidence of GD was 21.0/100,000 and toxic nodular goiter (TNG=STA+TMNG) occurred in 692 patients, corresponding to an annual incidence of 6.5/100,000. The incidence was higher in women compared with men (4.2:1). Seventy-five percent of the patients were diagnosed with GD, in whom thyroid-associated eye symptoms/signs occurred during diagnosis in every fifth patient. Geographical differences were observed.

CONCLUSION

The incidence of hyperthyroidism in Sweden is in a lower range compared with international reports. Seventy-five percent of patients with hyperthyroidism had GD and 20% of them had thyroid-associated eye symptoms/signs during diagnosis. The observed geographical differences require further studies.

Hyperthyroidism and other causes of thyrotoxicosis: management guidelines of the American Thyroid Association and American Association of Clinical Endocrinologists

OBJECTIVE

Thyrotoxicosis has multiple etiologies, manifestations, and potential therapies. Appropriate treatment requires an accurate diagnosis and is influenced by coexisting medical conditions and patient preference. This article describes evidence-based clinical guidelines for the management of thyrotoxicosis that would be useful to generalist and subspeciality physicians and others providing care for patients with this condition.

METHODS

The development of these guidelines was commissioned by the American Thyroid Association in association with the American Association of Clinical Endocrinologists. The American Thyroid Association and American Association of Clinical Endocrinologists assembled a task force of expert clinicians who authored this report. The task force examined relevant literature using a systematic PubMed search supplemented with additional published materials. An evidence-based medicine approach that incorporated the knowledge and experience of the panel was used to develop the text and a series of specific recommendations. The strength of the recommendations and the quality of evidence supporting each was rated according to the approach recommended by the Grading of Recommendations, Assessment, Development, and Evaluation Group.

RESULTS

Clinical topics addressed include the initial evaluation and management of thyrotoxicosis; management of Graves' hyperthyroidism using radioactive iodine, antithyroid drugs, or surgery; management of toxic multinodular goiter or toxic adenoma using radioactive iodine or surgery; Graves' disease in children, adolescents, or pregnant patients; subclinical hyperthyroidism; hyperthyroidism in patients with Graves' ophthalmopathy; and management of other miscellaneous causes of thyrotoxicosis.

CONCLUSIONS

One hundred evidence-based recommendations were developed to aid in the care of patients with thyrotoxicosis and to share what the task force believes is current, rational, and optimal medical practice.

Hyperthyroidism and other causes of thyrotoxicosis: management guidelines of the American Thyroid Association and American Association of Clinical Endocrinologists

BACKGROUND

Thyrotoxicosis has multiple etiologies, manifestations, and potential therapies. Appropriate treatment requires an accurate diagnosis and is influenced by coexisting medical conditions and patient preference. This article describes evidence-based clinical guidelines for the management of thyrotoxicosis that would be useful to generalist and subspeciality physicians and others providing care for patients with this condition.

METHODS

The development of these guidelines was commissioned by the American Thyroid Association in association with the American Association of Clinical Endocrinologists. The American Thyroid Association and American Association of Clinical Endocrinologists assembled a task force of expert clinicians who authored this report. The task force examined relevant literature using a systematic PubMed search supplemented with additional published materials. An evidence-based medicine approach that incorporated the knowledge and experience of the panel was used to develop the text and a series of specific recommendations. The strength of the recommendations and the quality of evidence supporting each was rated according to the approach recommended by the Grading of Recommendations, Assessment, Development, and Evaluation Group.

RESULTS

Clinical topics addressed include the initial evaluation and management of thyrotoxicosis; management of Graves' hyperthyroidism using radioactive iodine, antithyroid drugs, or surgery; management of toxic multinodular goiter or toxic adenoma using radioactive iodine or surgery; Graves' disease in children, adolescents, or pregnant patients; subclinical hyperthyroidism; hyperthyroidism in patients with Graves' ophthalmopathy; and management of other miscellaneous causes of thyrotoxicosis.

CONCLUSIONS

One hundred evidence-based recommendations were developed to aid in the care of patients with thyrotoxicosis and to share what the task force believes is current, rational, and optimal medical practice.

Epidemiology of subtypes of hyperthyroidism in Denmark: a population-based study

OBJECTIVE

Few population-based studies have described the epidemiology of subtypes of hyperthyroidism.

DESIGN

A prospective population-based study, monitoring two well-defined Danish cohorts in Aalborg with moderate iodine deficiency (n=311 102) and Copenhagen with only mild iodine deficiency (n=227 632).

METHODS

A laboratory monitoring system identified subjects with thyroid function tests suggesting overt hyperthyroidism (low s-TSH combined with high s-thyroxine or s-triiodothyronine). For all subjects, we collected information on medical history, thyroid scintigraphy and thyroid hormone receptor antibody (TRAb) measurement. Information was used to disprove or verify primary overt hyperthyroidism and to subclassify hyperthyroidism into nosological disorders.

RESULTS

From 1997 to 2000 (2 027 208 person-years of observation), we verified 1682 new cases of overt hyperthyroidism. The overall standardized incidence rate (SIR) per 100 000 person-years was 81.6, and was higher in Aalborg compared with Copenhagen (96.7 vs 60.0, P<0.001), giving an SIR ratio (SIRR (95% confidence interval (CI))) between moderate versus mild iodine-deficient areas of 1.6 (1.4-1.8). Nosological types of hyperthyroidism (percentage/SIRR (95% CI)): multinodular toxic goitre (MNTG) 44.1%/1.9 (1.6-2.2), Graves' disease (GD) 37.6%/1.2 (0.99-1.4), solitary toxic adenoma (STA) 5.7%/2.4 (1.3-3.5), 'mixed type' hyperthyroidism (TRAb-positive, scintigraphicly multinodular) 5.4%/6.0 (3.0-12), subacute thyroiditis 2.3%/0.9 (0.4-1.4), postpartum thyroid dysfunction 2.2%/1.6 (0.8-3.0), amiodarone-associated hyperthyroidism 0.8%/7.1 (1.1-65), hyperthyroidism after thyroid radiation 0.7%/12.3 (0.8-50), lithium-associated hyperthyroidism 0.7%/0.97 (0.4-4.8) and hyperthyroidism caused by various other factors 0.7%. Lifetime risk for overt hyperthyroidism was 10.5%/6.5%/2.4% (females/all/males).

CONCLUSION

Hyperthyroidism was common in Denmark with MNTG and GD as dominating entities. The higher incidence of hyperthyroidism in the most iodine-deficient region was caused by higher frequency of MNTG, 'mixed-type', STA and amiodarone-associated hyperthyroidism.

Urticaria and thyroid autoimmunity

BACKGROUND

Chronic urticaria is a common clinical condition whose etiology, in about 75% of cases, is unknown and is therefore called chronic idiopathic urticaria (CIU). A link between CIU and autoimmune thyroid diseases was proposed several decades ago. Here we review this topic.

SUMMARY

Several studies have been performed to determine if and to what degree there is an association between CIU and autoimmune thyroid diseases, particularly autoimmune thyroiditis. Many of these studies were not well controlled, however. Approximately one-fourth of CIU patients have serological evidence of thyroid autoimmunity, suggesting that these two disorders are associated. The mechanisms for the apparent association between CIU and serological evidence of thyroid autoimmunity are not clear. There are no data regarding the correlations between CIU and histological features of autoimmune thyroiditis or hypothyroidism. Despite this, there are anecdotal reports regarding L-thyroxine administration in patients with CIU.

CONCLUSIONS

Screening for thyroid autoimmunity is probably useful in patients with CIU. More solid evidence, based on still lacking well-conducted controlled studies, is desirable to determine if there is a therapeutic role for L-thyroxine treatment in ameliorating the skin manifestations of urticaria.

Thyroid-associated ophthalmopathy; quality of life follow-up of patients randomized to treatment with antithyroid drugs or radioiodine

OBJECTIVE

The objective of this study was to investigate quality of life (QoL) in patients with Graves' disease treated with radioiodine or antithyroid drugs.

DESIGN AND METHODS

The design of the study consists of an open, prospective, randomized multicenter trial between radioiodine and medical treatment. A total of 308 patients were included in the study group: 145 patients in the medical group and 163 patients in the radioiodine group. QoL was measured with a 36-item Short Form Health Status Survey questionnaire (SF-36) at six time points during the 48-month study period.

RESULTS

Patient who developed or got worse of thyroid-associated ophthalmopathy (TAO) at any time point during the 4-year study period (TAO group) had lower QoL when no respect was paid to the mode of treatment. TAO occurred in 75 patients who had radioiodine treatment at some time point during the study period as compared with TAO in 40 medically treated patients (P<0.0009). Comparisons between the group of patients who have had TAO versus the group without TAO, in relation to treatments and time, showed significantly decreased QoL scores for the TAO groups at several time points during the study. In patients without TAO, there were no differences in QoL related to mode of treatment.

CONCLUSIONS

The QoL in patients with Graves' ophthalmopathy was similar in radioiodine and medically treated patients, but patients who developed or had worsening of TAO had decreased QoL independent of mode of treatment. Furthermore, patients with TAO recovered physically within 1 year but it took twice as long for them to recover mentally.

Liver failure due to antithyroid drugs: report of a case and literature review

Hyperthyroidism is a common endocrine disorder affecting 2% of females and 0.5% of males worldwide and antithyroid drugs constitute the first line of treatment in the majority of cases. These agents may cause severe adverse effects and among them liver failure, although rare, is a potential lethal one. This case illustrates the sudden and abrupt deterioration of hepatic function due to antithyroid drug administration. This case along with a concise literature review is presented aiming to increase the awareness of endocrinologists of possible fatal complications from the everyday use of common agents such as antithyroid drugs.

Shifts in propylthiouracil and methimazole prescribing practices: antithyroid drug use in the United States from 1991 to 2008

CONTEXT

The thionamide antithyroid drugs methimazole and propylthiouracil are the mainstay of pharmacologic therapy for Graves' disease. However, little is known about the rate of use of these drugs and the prescribing practices of physicians treating hyperthyroidism.

OBJECTIVE

The objective of the study was to examine the frequency of methimazole and propylthiouracil use from years 1991 to 2008.

METHODS

The data were acquired by the U.S. Food and Drug Administration's Division of Epidemiology through two databases: IMS National Sales Perspectives and the Surveillance Data, Inc. Vector One: National database.

RESULTS

There was a 9-fold increase in the annual number of methimazole prescriptions during the study period, from 158,000 to 1.36 million per year. There was a 19% increase in the annual number of propylthiouracil prescriptions, from 348,000 to 415,000 per year. Propylthiouracil, which held two thirds of the market from 1991 to 1995, was surpassed by methimazole in 1996. Patient demographic data indicated that although 72% of methimazole prescriptions were for females, males were more likely to be on methimazole (82%) than females (74%) (P < 0.001, two tailed chi(2) test). The only demographic group in which methimazole use decreased was women of child-bearing age (5% decrease, P < 0.001, two tailed chi(2)). The incidence of hyperthyroidism in 2008 was estimated based on the number of new prescriptions of thionamides by age group and data from the 2008 U.S. census: 0.44 per 1000 for ages 0-11 yr, 0.26 per 1000 for ages 12-17 yr, 0.59 per 1000 for ages 18-44 yr, 0.78 per 1000 for ages 45-64 yr, and 1.01 per 1000 for ages 65+ yr.

CONCLUSIONS

Methimazole has become the most frequently prescribed antithyroid drug. The remarkable increase in the total number of dispensed thionamide prescriptions over the last 18 yr may indicate a trend toward pharmacological treatment as primary treatment of Graves' disease in the United States.

Cancer risk in patients hospitalised for Graves' disease: a population-based cohort study in Sweden

Background:

The possibility of an association of Graves’ disease (GD) with subsequent cancers raised by certain studies.

Methods:

Using a database on 18 156 hospitalised GD patients, subsequent cancers were ascertained.

Results:

Increased risks of thyroid and parathyroid tumours were limited to the early follow-up period, which is probably a surveillance bias. Cancer sites with observed excess included the mouth and breast, in contrast to decreased risks of colon cancer, melanoma and non-Hodgkin's lymphoma.

Conclusion:

Increased subsequent cancers in GD patients appeared to be balanced by decreased risks at other sites; chance cannot be excluded.

Hyperthyroidism and suicide: a retrospective cohort study in Sweden

OBJECTIVES

Mental symptoms and impaired quality of life commonly occur in patients treated for hyperthyroidism. Our aim was to determine whether a history of hyperthyroidism implies an increased risk of suicide.

DESIGN

Historic cohort study of 43,633 patients treated with radioiodine or surgery for hyperthyroidism between 1950 and 2005. The majority of the radioiodine-treated patients came from Stockholm. Two comparison cohorts consisted of 44,921 patients registered with an operation for atoxic nodular goitre between 1965 and 2005, and 354,861 patients with a cholecystectomy between 1965 and 2001.

METHODS

Subjects were followed from the date of diagnosis until death, emigration or end of follow-up. Information on outcome was obtained from population and health registers.

RESULTS

The number of observed suicide deaths was 134 in the study cohort. A naive comparison with the age-, sex- and calendar period-matched general Swedish population yielded a moderately increased standardized mortality ratio (SMR), but stratifications revealed that the excess was mainly driven by women from Stockholm, whose baseline suicide risk was higher than for women in the rest of Sweden. Using the population rates from Stockholm, the SMR among Stockholm women with Graves' disease was 1.14 (95% confidence intervals (CI) 0.66-1.86) and toxic goitre 0.99 (95% CI 0.51-1.72). A direct comparison between the study cohort and the combined comparison cohorts, with multiple adjustments (including adjustment for residence in Stockholm), yielded a relative risk of suicide of 0.93 (0.68-1.26).

CONCLUSIONS

This study did not confirm an increased risk of suicide among patients treated for hyperthyroidism.