Hypothyroidism and Type D Personality: Results From E-MPATHY, a Cross-sectional International Online Patient Survey.

CONTEXT: Between 10% and 15% of people with hypothyroidism experience persistent symptoms, despite achieving biochemical euthyroidism. The underlying causes are unclear. Type D personality (a vulnerability factor for general psychological distress) is associated with poor health status and symptom burden but has not been studied in people with hypothyroidism. OBJECTIVE: To investigate type D personality in hypothyroidism and explore associations with other characteristics and patient-reported outcomes. DESIGN: Multinational, cross-sectional survey. SETTING: Online. PARTICIPANTS: Individuals with self-reported, treated hypothyroidism. INTERVENTION: Questionnaire. MAIN OUTCOME MEASURES: Type D personality and associations with baseline characteristics, control of the symptoms of hypothyroidism by medication, satisfaction with care and treatment of hypothyroidism, impact of hypothyroidism on everyday living. RESULTS: A total of 3915 responses were received, 3523 of which were valid. The prevalence of type D personality was 54.2%. Statistically significant associations were found between type D personality and several respondent characteristics (age, marital status, ethnicity, household income, comorbidities, type of treatment for hypothyroidism, most recent TSH level), anxiety, depression, somatization, poor control of the symptoms of hypothyroidism by medication, dissatisfaction with care and treatment of hypothyroidism, and a negative impact of hypothyroidism on everyday living). DISCUSSION: Our study found a high prevalence of type D personality among people with hypothyroidism who responded to the survey. Type D personality may be an important determinant of dissatisfaction with treatment and care among people with hypothyroidism. Our findings require independent confirmation. Close collaboration between the disciplines of thyroidology and psychology is likely to be key in progressing our understanding in this area.

Use of thyroid hormones in hypothyroid and euthyroid patients: A survey of members of the Endocrine Society of Australia.

OBJECTIVE: Hypothyroidism is a common endocrine condition usually managed with levothyroxine (LT4). However, controversy remains around the use of liothyronine (LT3). We aimed to investigate the practices of Australian endocrinologists when managing patients with hypothyroidism, their use of LT3 + LT4 combination therapy and use of thyroid hormones in euthyroid patients. DESIGN AND PARTICIPANTS: Members of the Endocrine Society of Australia (ESA) were invited to participate in an online questionnaire. MEASUREMENTS: We analysed questionnaires that had complete demographic data. RESULTS: Eighty-seven questionnaires fulfilled the criteria. LT4 was used as first line treatment for hypothyroidism by all respondents. Only 45% reported that their patients were dispensed the brand of LT4 that they recommend. LT3 (alone or in combination) was prescribed by 44% in their clinical practice. Although 49% of respondents would consider LT3 + LT4 in patients with normal TSH who had ongoing symptoms of hypothyroidism, the inability of LT4 to restore normal physiology was ranked the least likely explanation for persistent symptoms and only 32% would consider it for themselves if they were diagnosed with hypothyroidism. The majority (55%), in accordance with evidence, would not prescribe thyroid hormone to euthyroid individuals but 39% would consider use in euthyroid female infertility with high levels of thyroid antibodies and 11% in euthyroid patients with a simple goitre growing over time. LT4 use in pregnancy was variable among members. CONCLUSIONS: Australian endocrinologists mostly follow international guidelines when prescribing thyroid hormone therapy and many prescribe combination LT3 and LT4 therapy, particularly for patients who remain symptomatic on LT4 monotherapy. Prescribing practices are largely similar to other countries who have completed similar questionnaires.

Patients' Persistent Symptoms, Clinician Demographics, and Geo-Economic Factors Are Associated with Choice of Therapy for Hypothyroidism by European Thyroid Specialists: The "THESIS" Collaboration.

Background: Hypothyroidism is common, however, aspects of its treatment remain controversial. Our survey aimed at documenting treatment choices of European thyroid specialists and exploring how patients' persistent symptoms, clinician demographics, and geo-economic factors relate to treatment choices. Methods: Seventeen thousand two hundred forty-seven thyroid specialists from 28 countries were invited to participate in an online questionnaire survey. The survey included respondent demographic data and treatment choices for hypothyroid patients with persistent symptoms. Geo-economic data for each country were included in the analyses. Results: The response rate was 32.9% (6058 respondents out of 17,247 invitees). Levothyroxine (LT4) was the initial treatment preferred by the majority (98.3%). Persistent symptoms despite normal serum thyrotropin (TSH) while receiving LT4 treatment were reported to affect up to 10.0% of patients by 75.4% of respondents, while 28.4% reported an increasing such trend in the past 5 years. The principal explanations offered for patients' persistent symptoms were psychosocial factors (77.1%), comorbidities (69.2%), and unrealistic patient expectations (61.0%). Combination treatment with LT4+liothyronine (LT3) was chosen by 40.0% of respondents for patients who complained of persistent symptoms despite a normal TSH. This option was selected more frequently by female thyroid specialists, with high-volume practice, working in countries with high gross national income per capita. Conclusions: The perception of patients' dissatisfaction reported by physicians seems lower than that described by hypothyroid patients in previous surveys. LT4+LT3 treatment is used frequently by thyroid specialists in Europe for persistent hypothyroid-like symptoms even if they generally attribute such symptoms to nonendocrine causes and despite the evidence of nonsuperiority of the combined over the LT4 therapy. Pressure by dissatisfied patients on their physicians for LT3-containing treatments is a likely explanation. The association of the therapeutic choices with the clinician demographic characteristics and geo-economic factors in Europe is a novel information and requires further investigation.

How patients experience thyroid eye disease.

Objective: To determine the impact of thyroid eye disease (TED) on patients in various stages of the disease. Background: TED is a debilitating and potentially sight-threatening inflammatory autoimmune disease that is frequently misdiagnosed. Challenging quality-of-life (QoL) issues can persist long after the active phase of disease has subsided. Methods: A 62-question survey was designed as a hypothesis-generating instrument to identify key issues confronting patients ≥18 years old with physician-diagnosed TED. Questions focused primarily on physical and emotional status, and QoL experiences in the 2 months prior to the survey. Data for individual questions are presented as summary statistics. Correlations between questions were determined using χ2 analyses. Results: The 443 respondents were 18 to >80 years old; >90% female, and >80% from the United States. Time since TED diagnosis ranged from <1 year to >10 years. Participants provided >500 free-form responses describing experiences of living with TED. Physical signs/symptoms were experienced by 307/443 (69%) patients. Of those responding to the QoL questions (N = 394), 53 (13%) reported symptoms improving, 73 (19%) reported symptoms worsening, and 255 (65%) reported no change in the 2 months prior to the survey. The most bothersome signs/symptoms were dry/gritty eyes, light sensitivity, bulging eyes, and pressure or pain behind the eyes. Respondents <60 years were significantly (p < 0.0001) more likely to report symptomatic TED than older patients. Of 394 respondents, 179 (45%) reported feeling depressed and/or anxious, 174 (44%) reported concern about their appearance, and 73 (19%) avoided public situations; 192 (49%) reported declines in confidence or feelings of general well-being, and 78 (20%) reported an inability to achieve goals. Activities limited by TED included reading, driving, and socializing. The proportion of respondents experiencing these negative QoL measures was higher when patients reported experiencing >5 symptoms, had been diagnosed within the last 5 years, or were <60 years of age. Conclusions: Physical manifestations of TED impact QoL for patients through all phases of the disease. It is essential that physicians and healthcare professionals become more familiar with patient experiences such as those described here to better help patients manage their disease.

Characteristics of specialists treating hypothyroid patients: the "THESIS" collaborative.

Introduction: Thyroid specialists influence how hypothyroid patients are treated, including patients managed in primary care. Given that physician characteristics influence patient care, this study aimed to explore thyroid specialist profiles and associations with geo-economic factors. Methods: Thyroid specialists from 28 countries were invited to respond to a questionnaire, Treatment of Hypothyroidism in Europe by Specialists: an International Survey (THESIS). Geographic regions were defined according to the United Nations Statistics Division. The national economic status was estimated using World Bank data on the gross national income per capita (GNI per capita). Results: 5,695 valid responses were received (response rate 33·0%). The mean age was 49 years, and 65·0% were female. The proportion of female respondents was lowest in Northern (45·6%) and highest in Eastern Europe (77·2%) (p <0·001). Respondent work volume, university affiliation and private practice differed significantly between countries (p<0·001). Age and GNI per capita were correlated inversely with the proportion of female respondents (p<0·01). GNI per capita was inversely related to the proportion of respondents working exclusively in private practice (p<0·011) and the proportion of respondents who treated >100 patients annually (p<0·01). Discussion: THESIS has demonstrated differences in characteristics of thyroid specialists at national and regional levels, strongly associated with GNI per capita. Hypothyroid patients in middle-income countries are more likely to encounter female thyroid specialists working in private practice, with a high workload, compared to high-income countries. Whether these differences influence the quality of care and patient satisfaction is unknown, but merits further study.

Use of thyroid hormones in hypothyroid and euthyroid patients: a 2022 THESIS questionnaire survey of members of the Latin American Thyroid Society (LATS).

PURPOSE: Inconsistencies in the medical management of hypothyroidism have been reported between endocrinologists in different countries. This study aimed to identify the attitudes of Latin America thyroid specialists towards the use of thyroid hormones. METHODS: Online survey of members of the Latin America Thyroid Society. RESULTS: 81/446 (18.2%) completed the questionnaire. Levothyroxine (LT4) was the initial treatment of choice for all respondents. 56.8% would consider LT4 use in biochemically euthyroid patients: infertile women with elevated anti-thyroid antibodies (46.9%), resistant depression (17.3%) and growing goiter (12%). Most respondents preferred tablets (39.5%) over liquid formulations (21.0%) or soft gel capsules (22.2%) and would not consider switching formulations in patients with persistent symptoms. 39.5% would never use LT4 + liothyronine (LT3) combination therapy in symptomatic euthyroid patients, due to low quality evidence for benefit. 60.5% reported that persistence of symptoms despite normal TSH is rare (below 5% of patients) and its prevalence has been stable over the last five years. Psychosocial factors (84.0%), comorbidities (86.4%) and the patient unrealistic expectation (72.8%) were considered the top three explanations for this phenomenon. CONCLUSION: LT4 tablets is the treatment of choice for hypothyroidism. A significant proportion of respondents would use LT4 in some groups of euthyroid individuals, contrasting the recommendations of the major clinical practice guideline indications. LT4 + LT3 combination treatment in euthyroid symptomatic patients was considered by nearly 50%. Practices based on weak or absent evidence included use of thyroid hormones for euthyroid subjects by 56.8% of respondents and use of LT4 + LT3 treatment by 60.5% of respondents for patients with persistent symptoms. In contrast to many European countries, LATS respondents report a low and unchanged proportion of dissatisfied patients over the last five years.

Hypothyroidism and Somatization: Results from E-Mode Patient Self-Assessment of Thyroid Therapy, a Cross-Sectional, International Online Patient Survey.

Background: Between 10% and 15% of hypothyroid patients experience persistent symptoms despite achieving biochemical euthyroidism. Unexplained persistent symptoms can be a sign of somatization. This is associated with distress and high health care resource use and can be classified as somatic symptom disorder (SSD). Prevalence rates for SSD differ depending on classification criteria and how they are ascertained, varying between 4% and 25%. As this has not been studied in hypothyroid patients before, the aim of this study was to document somatization in people with hypothyroidism and to explore associations with other patient characteristics and outcomes. Methods: Online, multinational cross-sectional survey of individuals with self-reported, treated hypothyroidism, which included the validated Patient Health Questionnaire-15 (PHQ-15) for assessment of somatization. Chi-squared tests with the Bonferroni correction were used to explore outcomes for respondents with a PHQ-15 score ≥10 (probable somatic symptom disorder [pSSD]) versus a PHQ-15 score <10 (absence of SSD). Results: A total of 3915 responses were received, 3516 of which contained the valid PHQ-15 data (89.8%). The median score was 11.3 (range 0-30 [confidence interval 10.9-11.3]). The prevalence of pSSD was 58.6%. Associations were found between pSSD and young age (p < 0.001), women (p < 0.001), not working (p < 0.001), having below average household income (p < 0.001), being treated with levothyroxine (LT4) (rather than combination of LT4 and L-triiodothyronine [LT3], LT3 alone, or desiccated thyroid extract) (p < 0.001), expression of the view that the thyroid medication taken did not control the symptoms of hypothyroidism well (p < 0.001), and with number of comorbidities (p < 0.001). pSSD was associated with respondent attribution of most PHQ-15 symptoms to the hypothyroidism or its treatment (p < 0.001), dissatisfaction with care and treatment of hypothyroidism (p < 0.001), a negative impact of hypothyroidism on daily living (p < 0.001), and with anxiety and low mood/depression (p < 0.001). Conclusions: This study demonstrates a high prevalence of pSSD among people with hypothyroidism and associations between pSSD and negative patient outcomes, including a tendency to attribute persistent symptoms to hypothyroidism or its treatment. SSD may be an important determinant of dissatisfaction with treatment and care among some hypothyroid patients.

Inter-observer Variability of Clinical Activity Score: Assessments in Patients With Thyroid Eye Disease.

PURPOSE: Thyroid eye disease (TED) can be difficult to manage. The range of available treatments is expanding rapidly; however, cost is a concern and some patients do not respond. The Clinical Activity Score (CAS) was devised as a measure of disease activity and a potential predictor of response to anti-inflammatory treatment. Despite the widespread use of the CAS, inter-observer variability has not been investigated. The aim of the study was to determine the inter-observer variability of the CAS in patients with TED. DESIGN: Prospective reliability analysis. METHODS: Nine patients with a spectrum of clinical features of TED were assessed by 6 experienced observers on the same day. Agreement among the observers was analyzed using the Krippendorff alpha. RESULTS: The Krippendorff alpha for the total CAS was 0.532 (95% CI = 0.199-0.665), whereas alpha values for the individual components of the CAS varied between 0.171 (CI = 0.000-0.334) for lid redness and 0.671 (CI = 0.294-1.000) for spontaneous pain. Assuming that a CAS value ≥3 implies suitability of the patient for anti-inflammatory treatment, the calculated Krippendorff alpha for agreement among assessors on whether treatment should be given or not given was 0.332 (95% CI = 0.0011-0.5862). CONCLUSIONS: This study has shown unreliable inter-observer variability in total CAS and most individual CAS components, thus highlighting the need for improving the performance of the CAS or seeking other methods to assess activity.

Teprotumumab in thyroid eye disease: wonder drug or great divider?

Progress in the management of thyroid eye disease (TED) has been slow for many decades. The recent introduction of teprotumumab (TEP) in the therapeutic arena for TED has had a major impact in view of its efficacy, particularly with respect to its ability to reduce proptosis. However, the high cost of TEP, limited availability to patients outside the USA, and the lack of data on cost-effectiveness are significant barriers to improving the care of patients with TED globally. Recent guidance from authoritative professional organisations deliver different perspectives on the role of TEP in the routine management of patients with TED, underscoring the complexities of interpreting the evidence. The advance that TEP undoubtedly represents in managing TED effectively has highlighted inequities faced by patients and uncertainties about appropriate metrics of efficacy. Professional organisations have an important role addressing these problems. Future studies need to focus on optimising the measurement of outcomes and on assessing cost-effectiveness.

Long-Term Follow-up of Graves Orbitopathy After Treatment With Short- or Long-Term Methimazole or Radioactive Iodine.

OBJECTIVE: The aim of this study was to compare long-term outcomes in terms of new onset or worsening of Graves orbitopathy (GO) in patients with Graves disease treated with different therapeutic modalities for hyperthyroidism. METHODS: A total of 1163 patients with Graves disease were enrolled in this study; 263 patients were treated with radioiodine and 808 patients received methimazole (MMI) therapy for a median of 18 months, of whom 178 patients continued MMI for a total of 96 months (long-term methimazole [LT-MMI]). The thyroid hormonal status and GO were evaluated regularly for a median of 159 months since enrollment. RESULTS: The rates of relapse, euthyroidism, and hypothyroidism at the end of follow-up were as follows: radioiodine treatment group: 16%, 22%, and 62%, respectively; short-term MMI group: 59%, 36%, and 5%, respectively; and LT-MMI group: 18%, 80%, and 2%, respectively. During the first 18 months of therapy, worsening of GO (11.5% vs 5.7%) and de novo development of GO (12.5% vs 9.8%) were significantly more frequent after radioiodine treatment (P <.004). Overall worsening and de novo development of GO from >18 to 234 months occurred in 26 (9.9%) patients in the radioiodine group and 8 (4.5%) patients in the LT-MMI group (P <.037). No case of worsening or new onset of GO was observed in patients treated with LT-MMI from >60 to 234 months of follow-up. CONCLUSION: Progression and development of GO were associated more with radioiodine treatment than with MMI treatment; GO may appear de novo or worsen years after radioiodine treatment but not after LT-MMI therapy.

Gut Microbiome Associated With Graves Disease and Graves Orbitopathy: The INDIGO Multicenter European Study.

CONTEXT: Gut bacteria can influence host immune responses but little is known about their role in tolerance-loss mechanisms in Graves disease (GD; hyperthyroidism caused by autoantibodies, TRAb, to the thyrotropin receptor, TSHR) and its progression to Graves orbitopathy (GO). OBJECTIVE: This work aimed to compare the fecal microbiota in GD patients, with GO of varying severity, and healthy controls (HCs). METHODS: Patients were recruited from 4 European countries (105 GD patients, 41 HCs) for an observational study with cross-sectional and longitudinal components. RESULTS: At recruitment, when patients were hyperthyroid and TRAb positive, Actinobacteria were significantly increased and Bacteroidetes significantly decreased in GD/GO compared with HCs. The Firmicutes to Bacteroidetes (F:B) ratio was significantly higher in GD/GO than in HCs. Differential abundance of 15 genera was observed in patients, being most skewed in mild GO. Bacteroides displayed positive and negative correlations with TSH and free thyroxine, respectively, and was also significantly associated with smoking in GO; smoking is a risk factor for GO but not GD. Longitudinal analyses revealed that the presence of certain bacteria (Clostridiales) at diagnosis correlated with the persistence of TRAb more than 200 days after commencing antithyroid drug treatment. CONCLUSION: The increased F:B ratio observed in GD/GO mirrors our finding in a murine model comparing TSHR-immunized with control mice. We defined a microbiome signature and identified changes associated with autoimmunity as distinct from those due to hyperthyroidism. Persistence of TRAb is predictive of relapse; identification of these patients at diagnosis, via their microbiome, could improve management with potential to eradicate Clostridiales.

Use of Thyroid Hormones in Hypothyroid and Euthyroid Patients: A THESIS questionnaire survey of members of the Irish Endocrine Society.

BACKGROUND: Replacement of thyroid hormones (TH) with Levothyroxine (LT4) is the treatment of choice for hypothyroidism, however, there are aspects of treatment where uncertainties exist and practice varies. Factors influencing initiation and choice of TH replacement may impact patient satisfaction, safety, and health care costs. METHODS: The aim of the study was to examine the attitudes of Irish endocrinologists regarding the treatment of hypothyroid and euthyroid patients with TH. Members of the Irish Endocrine Society (IES) were invited to participate in an online survey. RESULTS: Forty-eight invitations were sent, and 39 (81.3%) participants responded. All respondents favoured LT4 tablet therapy for treatment of hypothyroidism, but 20.5% prescribed combination therapy (LT4 and liothyronine), and 13% regularly used desiccated thyroid extract. A significant proportion (51%) might prescribe TH in euthyroid patients; 41% for thyroid auto-antibody positive women seeking pregnancy, 18% for goitre and 5% for unexplained fatigue. Many (38%) consider combination therapy in patients with persistent symptoms. Respondents reported seeing LT4 treated patients with persistent symptomatology more frequently and perceive psychosocial factors and comorbidities to be the most common reasons for such symptoms. CONCLUSION: LT4 tablets are the treatment of choice for hypothyroidism in Ireland. Approximately a third of Irish endocrinologists either regularly use, or would consider, liothyronine for hypothyroid patients. A significant proportion would give TH to euthyroid individuals in specific circumstances. The prescription of TH amongst Irish endocrinologists was generally in keeping with recommended practice, and areas where practice deviated from guidance were typically where evidence was conflicting or insufficient.

Use of thyroid hormones in hypothyroid and euthyroid patients: A THESIS questionnaire survey of UK endocrinologists.

OBJECTIVE: Management of hypothyroidism is controversial because of medication cost pressures and scientific uncertainty on how to address treatment dissatisfaction experienced by some patients. The objective was to investigate the experience and preferences of UK endocrinologists in use of thyroid hormones. DESIGN: Web-based survey. PATIENTS: UK endocrinologists were invited to participate. MEASUREMENTS: Responses to questionnaire. RESULTS: The response rate was 21% (272/1295). While levothyroxine monotherapy is regarded as the treatment of choice for hypothyroidism, 51% of respondents stated that combined treatment with levothyroxine and liothyronine could be considered for levothyroxine-treated patients whose symptoms persist despite normalisation of serum thyroid stimulating hormone (TSH) concentration. However, only 40% are currently prescribing such treatment, and just 23% would consider taking it themselves. A small minority prescribe desiccated thyroid extract, and those most likely to do so are aged over 60 years. Most respondents stated that they have no influence over brand or formulation of levothyroxine dispensed to their patients and expect no major differences in efficacy between different formulations. A total of 9% would prescribe levothyroxine for euthyroid enlarging goitre, and 29% for euthyroid female infertility with high titre thyroid peroxidase antibodies, despite recent trials finding no benefit. CONCLUSIONS: UK endocrine practice in management of hypothyroidism is broadly in line with international guidance. However, a minority of respondents would consider thyroid hormone supplementation in euthyroid individuals for female infertility, enlarging goitre, and other indications in which evidence of efficacy is lacking. Willingness to consider prescribing combined levothyroxine and liothyronine, for hypothyroid symptoms which persist despite normalised TSH, has increased in comparison to previous international surveys, despite inconsistent evidence of benefit.

The enigma of persistent symptoms in hypothyroid patients treated with levothyroxine: A narrative review.

A significant minority of patients with hypothyroidism report persistent symptoms despite achieving normal thyroid biochemistry after levothyroxine (L-T4) replacement. Four principal lines of thinking, which are not mutually exclusive, may explain this enigma. The 'low tissue liothyronine hypothesis' emphasizes the potential imperfections of L-T4 replacement therapy that may lead to hypothyroidism in some tissues such as the brain, while others (eg hypothalamus) are euthyroid. The 'Somatic Symptom and Related Disorders hypothesis' draws attention to an incidental coexistence of a diagnosis of Somatic Symptom and Related Disorders in patients with treated hypothyroidism. The 'autoimmune neuroinflammation hypothesis' highlights the potential consequences of inflammatory mediators due to thyroid autoimmunity (the commonest cause of hypothyroidism) on the brain. The 'comorbidities and psychosocial hypothesis' implicates a variety of physical and psychosocial factors that have been noted to be associated with a diagnosis of hypothyroidism, which may be primarily the cause of persistent complaints. Over the past twenty years, a great deal of time and effort has been expended pursuing the 'low tissue liothyronine hypothesis', which has failed to yield results that translate to patient benefits. This has skewed the balance in clinical practice, in favour of pursuing answers relating to L-T4 and liothyronine combination treatment, while the alternative explanations have been downplayed and potentially useful interventions have been given insufficient attention.

Management of thyroid eye disease: a Consensus Statement by the American Thyroid Association and the European Thyroid Association.

Thyroid eye disease (TED) remains challenging for clinicians to evaluate and manage. Novel therapies have recently emerged, and their specific roles are still being determined. Most patients with TED develop eye manifestations while being treated for hyperthyroidism and under the care of endocrinologists. Endocrinologists, therefore, have a key role in diagnosis, initial management, and selection of patients who require referral to specialist care. Given that the need for guidance to endocrinologists charged with meeting the needs of patients with TED transcends national borders, and to maximize an international exchange of knowledge and practices, the American Thyroid Association and European Thyroid Association joined forces to produce this Consensus Statement.

Management of Thyroid Eye Disease: A Consensus Statement by the American Thyroid Association and the European Thyroid Association.

Thyroid eye disease (TED) remains challenging for clinicians to evaluate and manage. Novel therapies have recently emerged, and their specific roles are still being determined. Most patients with TED develop eye manifestations while being treated for hyperthyroidism and under the care of endocrinologists. Endocrinologists, therefore, have a key role in diagnosis, initial management, and selection of patients who require referral to specialist care. Given that the need for guidance to endocrinologists charged with meeting the needs of patients with TED transcends national borders, and to maximize an international exchange of knowledge and practices, the American Thyroid Association and European Thyroid Association joined forces to produce this consensus statement.

Use of thyroid hormone in hypothyroid patients and euthyroid subjects in Spain: A THESIS* questionnaire survey.

BACKGROUND: Hypothyroidism is one of the leading conditions in endocrinology. Despite that fact, clinical indications for treatment still vary among Spanish specialists. AIMS: To identify attitudes of Spanish specialists relating to the use of levothyroxine (LT4) and the management of hypothyroidism. METHODS: The members of the Sociedad Española de Endocrinología y Nutrición (Spanish Society of Endocrinology and Nutrition) were invited to participate in a web-based survey. The survey, initially in English, was modified to reflect in accordance with the availability of thyroid hormone formulations in Spain. RESULTS: A total of 505 of 1956 (25.8%) members (66% female) completed the survey; 97.4% declared that LT4 is the first-line therapy for hypothyroidism. The indications for LT4 therapy in euthyroidism were infertility in thyroid antibody-positive women (48.5%) and simple goitre (21.2%). However, 44.2% of specialists reported that there was no indication for LT4 therapy in such patients. Only a minority of respondents (2.6%) considered combining LT4 with liothyronine as the treatment of choice from inception, whereas 49% stated that it should never be used. CONCLUSIONS: The standard of treatment of hypothyroidism in Spain is almost exclusively with LT4 tablets. Availability of other formulations of LT4 or combination therapy for hypothyroidism management remains to be explored, especially in patients with persistent symptoms. Notably, non-evidence-based use of LT4 is widely practiced in Spain for euthyroid women with autoimmune thyroiditis and fertility issues.