A nationwide registry-based observational study of thyroid disease incidence in the Faroe Islands.

OBJECTIVE: The occurrence of thyroid disease varies among populations. While the iodine nutrition level of the Faroese seems to have been decreasing over the past decades, there is no systematic evaluation of the thyroid disease pattern in the Faroe Islands. Such knowledge of thyroid disease occurrence in the North Atlantic region may support healthcare planning and prevention. To investigate incidence rates, including subtypes of thyroid diseases, and demographic characteristics of thyroid disease patients in the Faroe Islands, to improve understanding of the patterns and trends of these disorders. DESIGN AND METHOD: A registry-based observational study was conducted over 10 years, encompassing all adult Faroese individuals. PATIENTS AND MEASUREMENTS: Health records from general practitioners and hospitals were used to identify incident cases of thyroid diseases. Validation was performed using multiple data sources. The incidence rates were standardised using population data from the middle of the study period 2006-2018. RESULTS: Among the 1152 individuals diagnosed with thyroid disease, the standardised incidence rates per 100,000 person-years were 55 for hyperthyroidism and 112 for hypothyroidism, and around four times higher in women than in men. Hashimoto's thyroiditis was the dominant cause of hypothyroidism, while Graves' disease was the leading cause of hyperthyroidism. The incidence of hypothyroidism increases with age. A decreasing trend was observed over time for both hypothyroidism and hyperthyroidism. CONCLUSION: Considering the decrease in iodine nutrition levels over the past decades, we were surprised by the high incidence of autoimmune thyroid disease. The findings highlight the need for continuous monitoring of thyroid disease occurrence in coastal areas of the North Atlantic Ocean.

Does iodine fortification affect the risk of atrial fibrillation in incident hyperthyroidism? A national register-based cohort.

OBJECTIVE: Iodine fortification (IF) induces an initial increase followed by a decrease in the incidence of hyperthyroidism in the general population. Within the population of hyperthyroid patients, the sex-, age- and subtype distribution changes after IF. The risk of atrial fibrillation (AF) in hyperthyroid patients may be influenced by these factors. Therefore, we aimed to examine how the association between incident hyperthyroidism and AF was affected by IF increasing the population iodine intake from moderate-mild iodine deficiency to low adequacy. DESIGN, PATIENTS AND MEASUREMENTS: Incident hyperthyroid patients were included at the date of first inpatient or outpatient diagnosis, and AF diagnoses within 3 months before to 6 months after the index date were identified in Danish nationwide registers, 1997-2018. The relative risk (RR) of AF each calendar year (reference: 1997; IF introduced: 2000) was analyzed in Poisson regression models adjusted for age, sex, educational level, geographic region, and comorbidities. RESULTS: Overall, in 62,201 patients with incident hyperthyroidism 7.9% were diagnosed with AF. There was a minor nonsignificantly increased risk of AF during the first years after IF followed by a gradual decrease to RR 0.76 (0.62-0.94) in 2017. There were no statistically significant differences in the development in the risk of AF by sex, age group, or geographic region. CONCLUSIONS: Results indicate that IF may reduce the risk of concomitant AF in hyperthyroid patients. If these results are confirmed, IF may not only reduce the population incidence of hyperthyroidism but also reduce the burden of morbidity in the remaining hyperthyroid patients.

Does thyroid diseases contribute to the natural history of idiopathic adult-onset dystonia? Data from the Italian Dystonia Registry.

A few earlier observations and recent controlled studies pointed to the possible contribution of thyroid diseases in idiopathic adult-onset dystonia (IAOD). The aim of this study was to investigate the association between thyroid status and clinical characteristics of IAOD, focusing on dystonia localization, spread, and associated features such as tremors and sensory tricks. Patients were identified from those included in the Italian Dystonia Registry, a multicentre dataset of patients with adult-onset dystonia. The study population included 1518 IAOD patients. Patients with hypothyroidism and hyperthyroidism were compared with those without any thyroid disease. In the 1518 IAOD patients, 167 patients (11%; 95% CI 9.5-12.6%) were diagnosed with hypothyroidism and 42 (2.8%; 95% CI 1.99-3.74) with hyperthyroidism. The three groups were comparable in age at dystonia onset, but there were more women than men in the groups with thyroid disease. Analysing the anatomical distribution of dystonia, more patients with blepharospasm were present in the hyperthyroidism group, but the difference did not reach statistical significance after the Bonferroni correction. The remaining dystonia-affected body sites were similarly distributed in the three groups, as did dystonia-associated features and spread. Our findings provided novel information indicating that the high rate of thyroid diseases is not specific for any specific dystonia subpopulation and does not appear to influence the natural history of the disease.

High prevalence of erectile dysfunction in men with hyperthyroidism: a meta-analysis.

OBJECTIVE: The objective of this study was to evaluate the association between hyperthyroidism and the risk of developing erectile dysfunction (ED). METHODS: A comprehensive search of multiple databases, including PubMed, Embase, Cochrane, and Web of Science, was conducted to identify relevant studies investigating the relationship between hyperthyroidism and ED in men. The quality of the included studies was assessed using the Newcastle‒Ottawa Quality Rating Scale, and a meta-analysis was performed using Stata 16.0 and RevMan 5.3 software. RESULTS: A total of four papers encompassing 25,519 study subjects were included in the analysis. Among these, 6,429 individuals had hyperthyroidism, while 19,090 served as controls. The overall prevalence of ED in patients with hyperthyroidism was determined to be 31.1% (95% CI 0.06-0.56). In patients with uncomplicated hyperthyroidism, the incidence of ED was 21.9% (95% CI 0.05-0.38). The combined odds ratio (OR) for the four studies was 1.73 (OR: 1.73; 95% CI [1.46-2.04]; p < .00001). CONCLUSION: Our findings demonstrate a higher incidence of ED in patients with hyperthyroidism. These results provide valuable information for healthcare professionals and can facilitate discussions surrounding appropriate treatment options for ED in patients with hyperthyroidism.

GRADE-ADOLOPMENT of hyperthyroidism treatment guidelines for a Pakistani context.

INTRODUCTION: The prevalence of hyperthyroidism in Pakistan is 2.9%, which is two times higher than in the United States. Most high-quality hyperthyroidism clinical practice guidelines (CPGs) used internationally originate from high-income countries in the West. Local CPGs in Pakistan are not backed by transparent methodologies. We aimed to produce comprehensive, high-quality CPGs for the management of hyperthyroidism in Pakistan. METHODS: We employed the GRADE-ADOLOPMENT approach utilizing the 2016 American Thyroid Association Guidelines for Diagnosis and Management of Hyperthyroidism and Other Causes of Thyrotoxicosis as the source CPG. Recommendations from the source guideline were either adopted as is, excluded, or adapted according to our local context. RESULTS: The source guideline included a total of 124 recommendations, out of which 71 were adopted and 49 were excluded. 4 recommendations were carried forward for adaptation via the ETD process, with modifications being made to 2 of these. The first addressed the need for liver function tests (LFTs) amongst patients experiencing symptoms of hepatotoxicity while being treated with anti-thyroid drugs (ATDs). The second pertained to thyroid status testing post-treatment by radioactive iodine (RAI) therapy for Graves' Disease (GD). Both adaptations centered around the judicious use of laboratory investigations to reduce costs of hyperthyroidism management. CONCLUSION: Our newly developed hyperthyroidism CPGs for Pakistan contain two context-specific modifications that prioritize patients' finances during the course of hyperthyroidism management and to limit the overuse of laboratory testing in a resource-constrained setting. Future research must investigate the cost-effectiveness and risk-benefit ratio of these modified recommendations.

Farming activity and risk of treated thyroid disorders: Insights from the TRACTOR project, a nationwide cohort study.

BACKGROUND: Epidemiological data regarding thyroid diseases are lacking, in particular for occupationally exposed populations. OBJECTIVES: To compare the risk of hypothyroidism and hyperthyroidism between farming activities within the complete population of French farm managers (FMs). METHODS: Digital health data from retrospective administrative databases, including insurance claims and electronic health/medical records, was employed. This cohort data spanned the entirety of French farm managers (FMs) who had undertaken work at least once from 2002 to 2016. Survival analysis with the time to initial medication reimbursement as timescale was used to examine the association (hazard ratio, HR) between 26 specific farming activities and both treated hypothyroidism and hyperthyroidism. A distinct model was developed for each farming activity, comparing FMs who had never engaged in the specific farming activity between 2002 and 2016 with those who had. All analyses were adjusted for potential confounders (e.g., age), and sensitivity analyses were conducted. RESULTS: Among 1088561 FMs (mean age 46.6 [SD 14.1]; 31% females), there were 31834 hypothyroidism cases (75% females) and 620 hyperthyroidism cases (67% females), respectively. The highest risks were observed for cattle activities for both hyperthyroidism (HR ranging from 1.75 to 2.42) and hypothyroidism (HR ranging from 1.41 to 1.44). For hypothyroidism, higher risks were also observed for several animal farming activities (pig, poultry, and rabbit), as well as fruit arboriculture (HR = 1.22 [1.14-1.31]). The lowest risks were observed for activities involving horses. Sex differences in the risk of hypothyroidism were observed for eight activities, with the risk being higher for males (HR = 1.09 [1.01-1.20]) than females in viticulture (HR = 0.97 [0.93-1.00]). The risk of hyperthyroidism was two times higher for male dairy farmers than females. DISCUSSION: Our findings offer a comprehensive overview of thyroid disease risks within the FM community. Thyroid ailments might not stem from a single cause but likely arise from the combined effects of various causal agents and triggering factors (agricultural exposome). Further investigation into distinct farming activities-especially those involving cattle-is essential to pinpoint potential risk factors that could enhance thyroid disease monitoring in agriculture.

Long-term Effect of Thyrotropin-binding Inhibitor Immunoglobulin on Atrial Fibrillation in Euthyroid Patients.

OBJECTIVE: Individuals with hyperthyroidism are at an increased risk of atrial fibrillation (AF), but the association between autoantibodies and AF or cardiovascular mortality in individuals who have returned to normal thyroid function remains unclear. METHODS: The study utilized electronic medical records from National Taiwan University Hospital between 2000 and 2022. Each hyperthyroidism patient had at least 1 thyrotropin-binding inhibiting immunoglobulin (TBII) measurement. The relationship between TBII levels and the risk of AF and cardiovascular mortality was assessed using multivariable Cox regression models and Kaplan-Meier survival analysis. RESULTS: Among the 14 618 enrolled patients over a 20-year timeframe, 173 individuals developed AF, while 46 experienced cardiovascular mortality. TBII values exceeding 35% were significantly associated with an elevated risk of AF for both the first TBII (hazard ratio {HR} 1.48 [1.05-2.08], P = .027) and mean TBII (HR 1.91 [1.37-2.65], P < .001). Furthermore, after free T4 levels had normalized, a borderline association between first TBII and AF (HR 1.59 [0.99-2.56], P = .056) was observed, while higher mean TBII increased AF (HR 1.78 [1.11-2.85], P = .017). Higher first and mean TBII burden continued to significantly impact the incidence of cardiovascular mortality (HR 6.73 [1.42-31.82], P = .016; 7.87 [1.66-37.20], P = .009). Kaplan-Meier analysis demonstrated that elevated TBII levels increased the risk of AF and cardiac mortality (log-rank P = .035 and .027, respectively). CONCLUSION: In euthyroid individuals following antithyroid treatment, elevated circulating TBII levels and burden are associated with an elevated risk of long-term incident AF and cardiovascular mortality. Further reduction of TBII level below 35% will benefit to clinical outcomes.

Risk of Incident Thyroid Dysfunction in the Post-Acute Phase of COVID-19: A Population-Based Cohort Study in Hong Kong.

OBJECTIVE: The evidence of thyroid dysfunction in the post-acute phase of SARS-CoV-2 infection is limited. This study aimed to evaluate the risk of incident thyroid dysfunction in the post-acute phase of COVID-19. METHODS: This retrospective, propensity-score matched, population-based study included COVID-19 patients and non-COVID-19 individuals between January 2020 and March 2022, identified from the electronic medical records of the Hong Kong Hospital Authority. The cohort was followed up until the occurrence of outcomes, death, or 31 January 2023, whichever came first. Patients with COVID-19 were 1:1 matched to controls based on various variables. The primary outcome was a composite of thyroid dysfunction (hyperthyroidism, hypothyroidism, initiation of antithyroid drug or levothyroxine, and thyroiditis). Cox regression was employed to evaluate the risk of incident thyroid dysfunction during the post-acute phase. RESULTS: A total of 84 034 COVID-19 survivors and 84 034 matched controls were identified. Upon a median follow-up of 303 days, there was no significant increase in the risk of diagnosed thyroid dysfunction in the post-acute phase of COVID-19 (hazard ratio [HR] 1.058, 95% confidence interval 0.979-1.144, P = .154). Regarding the secondary outcomes, patients with COVID-19 did not have increased risk of hyperthyroidism (HR 1.061, P = .345), hypothyroidism (HR 1.062, P = .255), initiation of antithyroid drug (HR 1.302, P = .070), initiation of levothyroxine (HR 1.086, P = .426), or thyroiditis (P = .252). Subgroup and sensitivity analyses were largely consistent with the main analyses. CONCLUSION: Our population-based cohort study provided important reassuring data that COVID-19 was unlikely to be associated with persistent effects on thyroid function.

Prognostic implications of thyroid disease in patients with atrial fibrillation.

Atrial fibrillation (AF) is often accompanied by thyroid disease (THD). This study aimed to explore the relationship between THD and the occurrence of significant clinical outcomes in patients with AF. This post hoc analysis utilized data from the MISOAC-AF trial (NCT02941978), which enrolled hospitalized patients with AF. Patients were categorized based on their THD history into hyperthyroidism, hypothyroidism, or euthyroidism. Cox regression models were employed to calculate unadjusted and adjusted hazard ratios (aHRs). The primary outcomes of interest included all-cause mortality, cardiovascular death, and hospitalizations during the follow-up period. The study included 496 AF patients (mean age 73.09 ± 11.10 years) with available THD data, who were followed-up for a median duration of 31 months. Among them, 16 patients (3.2%) had hyperthyroidism, 141 (28.4%) had hypothyroidism, and 339 (68.4%) had no thyroid disease. Patients with hypothyroidism exhibited higher rates of hospitalization during follow-up (aHR: 1.57, 95% CI 1.12 to 2.20, p = 0.025) compared to the euthyroid group. Elevated levels of thyroid-stimulating hormone (TSH) were correlated with an increased risk of cardiovascular mortality (aHR: 1.03, 95% CI 1.01 to 1.05, p = 0.007) and hospitalizations (aHR: 1.06, 95% CI 1.01 to 1.12, p = 0.03). Conversely, lower levels of triiodothyronine (T3) were associated with higher risks of all-cause mortality (aHR: 0.51, 95% CI 0.31 to 0.82, p = 0.006) and cardiovascular mortality (aHR: 0.42, 95% CI 0.23 to 0.77, p = 0.005). Among patients with AF, hypothyroidism was associated with increased hospitalizations. Furthermore, elevated TSH levels and decreased T3 levels were linked to higher cardiovascular and all-cause mortality risks, respectively.

Increased risk of incident gout in patients with hyperthyroidism: a nationwide retrospective cohort study.

Previous studies have reported that thyroid dysfunction is associated with increased serum uric acid levels; however, the relationship between hyperthyroidism and incidence of clinical manifestations of gout has not been fully investigated. Therefore, this study aimed to longitudinally investigate the risk of gout in patients with hyperthyroidism. This nationwide retrospective cohort study used data from the Korean National Health Claims Database. We included 76,494 patients with hyperthyroidism and 76,542 age- and sex-matched controls. A Cox proportional hazard regression model was used to adjust for potential confounders and estimate the risk of incident gout in patients with hyperthyroidism. During a mean follow-up of 9 years, incident gout developed in 3,655 (4.8%) patients with hyperthyroidism and 3251 (4.2%) controls. Hyperthyroidism was significantly associated with increased risk of incident gout [adjusted hazard ratio (HR), 1.12; 95% confidence interval (CI) 1.07-1.18], independent of baseline metabolic profiles. The median time from the diagnosis of hyperthyroidism to the development of gout was 6 years. When stratified by age and sex, the risk of gout was still significant in the < 50-year age group (HR: 1.2, 95% CI 1.12-1.29) and males (HR: 1.21, 95% CI 1.12-1.30), but not in the older age group (> 50 years) and females. Hyperthyroidism is an important risk factor for incident gout, particularly in younger age groups (< 50 years) and males. Our results highlight the importance of continuous screening for gout in patients with hyperthyroidism.

Association between physical activity and thyroid function in American adults: a survey from the NHANES database.

OBJECTIVE: Physical activity (PA) is closely related to our lives, and the effects of PA on thyroid function have not been elucidated. METHODS: Using data from the National Health and Nutrition Examination Survey (NHANES) 2007-2012, we included 5877 participants and analyzed the associations of thyroid function with weekly physical activity (PAM, expressed in metabolic equivalents of task) and physical activity time (PAT) in American adults. Univariate and multivariate logistic analyses were used to demonstrate the associations of PAM and PAT with the primary outcome. Linear regression analysis was performed to determine the associations between thyroid biochemical indicators/diseases and PAM/PAT. RESULTS: Our study revealed noticeable sex differences in daily PA among the participants. The odds ratio of the fourth versus the first quartile of PAM was 3.07 (confidence interval, CI [1.24, 7.58], p = 0.02) for overt hypothyroidism, 3.25 (CI [1.12, 9.45], p = 0.03) for subclinical hyperthyroidism in adult men. PAT in the range of 633-1520 min/week was found to be associated with the occurrence of subclinical hyperthyroidism [p < 0.001, OR (95% CI) = 5.89 (1.85, 18.80)], PAT of the range of > 1520 min/week was found to be associated with the occurrence of overt hypothyroidism [p < 0.001, OR (95% CI) = 8.70 (2.80, 27.07)] and autoimmune thyroiditis (AIT) [p = 0.03, OR (95% CI) = 1.42 (1.03, 1.97)] in adult men. When PAM < 5000 MET*minutes/week or PAT < 1000 min/week, RCS showed an L-shaped curve for TSH and an inverted U-shaped curve for FT4. The changes in FT3 and TT3 in men were linearly positively correlated with PAM and PAT, while TT4 is linearly negatively correlated. CONCLUSION: The amount of daily physical activity of American adults is strongly associated with changes in thyroid function, including thyroid hormone levels and thyroid diseases. Thyroid hormone levels were varied to a certain extent with changes in PAM and PAT.

Zinc and Ferritin Levels and Their Associations with Functional Disorders and/or Thyroid Autoimmunity: A Population-Based Case-Control Study.

Population zinc and iron status appear to be associated with an increased risk of thyroid function abnormalities and thyroid autoimmunity (AITD). In the present study, we aimed to determine whether zinc and/or iron levels (assessed by ferritin levels) were associated with the presence of AITD and with alterations in thyroid function. A population-based case-control study (n = 1048) was conducted (cases: n = 524; controls: n = 524). Participants were measured for blood concentrations of zinc and ferritin, TSH, FT4, FT3, and thyroid autoantibodies. No significant differences were found in relation to ferritin levels between cases and controls. Among cases, the prevalence of low zinc levels in those with hypothyroidism (both subclinical and overt) was 49.1% [odds ratio (OR) of low zinc levels: 5.926; 95% CI: 3.756-9.351]. The prevalence of low zinc levels in participants with hyperthyroidism (both subclinical and overt) was 37.5% [OR of low zinc levels: 3.683; 95% CI: 1.628-8.33]. The zinc value that best discriminated the highest frequency of AITD was 70.4 µg/dL [sensitivity: 0.947, 1-specificity: 0.655, specificity: 0.345]. The highest frequency of AITD was calculated based on a zinc value <70 µg/dL (relative to a normal value), with this frequency being significantly higher in cases than in controls [OR: 9.3; 95% CI: 6.1-14.3 (p = 0.001)]. In conclusion, the results of our study suggest that zinc deficiency is associated with an increased frequency of functional thyroid disorders and thyroid autoimmunity.

THE RELATION OF THYROID DISTURBANCE AND ISCHEMIC HEART DISEASE IN IRAQI PATIENTS.

This study conducted in Baghdad focused on patients with coronary heart disease admitted to three hospitals. The study included 60 Iraqi patients with coronary heart disease and a control group of 30 healthy individuals. Blood samples were collected from both groups after fasting. The study analyzed the demographic characteristics of the patients and control group, including age groups, sex distribution, and BMI. The majority of patients had hypertension, while 58.33% had diabetes. The study found that IHD patients had significantly higher T3 and T4 levels compared to the control group. However, there was no significant difference in TSH levels. The study also examined thyroid function parameters among different age groups and found no significant differences in individuals with hypothyroidism. The highest prevalence of hyperthyroidism was among individuals with hypertension, while the highest spread of hypothyroidism was among individuals with diabetes. The study observed significant differences in mean HbA1c levels among the three groups, with the highest levels in patients with hypothyroidism. In conclusion, this study suggests potential alterations in thyroid function associated with ischemic heart disease and emphasizes the need for further research on the clinical implications and underlying mechanisms involved.

The Clinical Characteristics and Outcomes of COVID-19 Patients with Pre-Existing Thyroid Dysfunction: A Nationwide Study.

To which extent the pre-existing hypothyroidism or hyperthyroidism has an impact on coronavirus infection 2019 (COVID-19) outcomes remains unclear. The objective of this study was to evaluate COVID-19 morbidity and mortality in patients with pre-existing thyroid dysfunction. A retrospective cohort of patients with a polymerase chain reaction (PCR)-confirmed COVID-19 infection (n=14 966) from March 11 to May 30, 2020, was established using the database of the Turkish Ministry of Health. We compared the morbidity and mortality rates of COVID-19 patients with pre-existing hypothyroidism (n=8813) and hyperthyroidism (n=1822) to those patients with normal thyroid function (n=4331). Univariate and multivariate regression analyses were performed to identify the factors associated with mortality. Mortality rates were higher in patients with hyperthyroidism (7.7%) and hypothyroidism (4.4%) than those with normal thyroid function (3.4%) (p<0.001 and p=0.008, respectively). Pre-existing hyperthyroidism was significantly associated with an increased risk of mortality (OR 1.54; 95% CI, 1.02-2.33; p=0.042) along with advanced age, male gender, lymphopenia and chronic kidney disease (p<0.001 for all). Although a potential trend was noted, the association between pre-existing hypothyroidism and mortality was not significant (OR 1.36; 95% CI, 0.99-1.86; p=0.055). In conclusion, this study showed an association between pre-existing hyperthyroidism with higher COVID-19 mortality. A potential trend towards increased mortality was also observed for hypothyroidism. The risk was more pronounced in patients with hyperthyroidism.

Control of Thyroid Dysfunction in Spanish Population Registered in the Primary Care Clinical Database: An Analysis of the Proportion of Patients with Thyrotropin Values Outside the Reference Range.

Inadequate control of thyroid dysfunction is common and has deleterious health consequences. Our objective was to determine the prevalence of TSH values outside the reference range, as an indicator of inadequate control of hypothyroidism and hyperthyroidism in patients undergoing treatment for thyroid dysfunction in Spain. An observational, retrospective, non-interventional study was conducted using the Primary Care Clinical Database (BDCAP). Patients treated with thyroid hormone for hypothyroidism and with antithyroid drugs for hyperthyroidism were identified. We assessed serum TSH concentration, considering values from 0.4 to 4.0 mU/l as the reference interval. We found 360 313 people with hypothyroidism on thyroid hormone replacement and 9239 with hyperthyroidism on antithyroid drugs therapy. TSH values outside the reference range in hypothyroid subject were detected in 126 866 (35.20%) people, of whom 107 205 (29.75%) had TSH>4.0 mU/l, suggesting inappropriately low doses of levothyroxine, and 19 661 (5.46%) had TSH<0.4 mU/l, suggesting inappropriate over replacement. In the hyperthyroid group, TSH values outside the reference range were observed in 4252 (46.02%) patients. There were 2833 (30.66%) patients with TSH<0.4 mU/l, suggesting undertreatment, and 1419 (15.36%) with TSH>4.0 mU/l, suggesting overtreatment with antithyroid medication. People over 65 years of age had a lower frequency of undertreatment of hypothyroidism and a lower frequency of overtreatment and undertreatment of hyperthyroidism. In conclusion, our results suggest that inadequate control of thyroid dysfunction, due to its high frequency and its consequences for health, is a public health problem that should be addressed by clinicians and health authorities.

Migraine and thyroid dysfunction: Co-occurrence, shared genes and biological mechanisms.

BACKGROUND AND PURPOSE: Migraine and thyroid dysfunction, particularly hypothyroidism, are common medical conditions and are known to have high heritability. Thyroid function measures, thyroid stimulating hormone (TSH) and free thyroxine (fT4), are also known to be genetically influenced. Although observational epidemiological studies report an increased co-occurrence of migraine and thyroid dysfunction, a clear and combined interpretation of the findings is currently lacking. A narrative review is provided of the epidemiological and genetic association evidence linking migraine, hypothyroidism, hyperthyroidism and thyroid hormones TSH and fT4. METHODS: An extensive literature search was conducted in the PubMed database for epidemiological, candidate gene and genome-wide association studies using the terms migraine, headache, thyroid hormones, TSH, fT4, thyroid function, hypothyroidism and hyperthyroidism. RESULTS: Epidemiological studies suggest a bidirectional relationship between migraine and thyroid dysfunction. However, the nature of the relationship remains unclear, with some studies suggesting migraine increases the risk for thyroid dysfunction whilst other studies suggest the reverse. Early candidate gene studies have provided nominal evidence for MTHFR and APOE, whilst more recently genome-wide association studies have provided robust evidence for THADA and ITPK1 being associated with both migraine and thyroid dysfunction. CONCLUSIONS: These genetic associations improve our understanding of the genetic relationship between migraine and thyroid dysfunction, provide an opportunity to develop biomarkers to identify migraine patients most likely to benefit from thyroid hormone therapy, and indicate that further cross-trait genetic studies have excellent potential to provide biological insight into their relationship and inform clinical interventions.

Increased prevalence of thyroid dysfunction in Tehran - HAMRAH study.

BACKGROUND: The aim of the current study is to assess the prevalence of different categories of thyroid dysfunction and their associated risk factors among the modern urban population of Tehran, the capital of Iran. METHODS: The present investigation is a sub-study of the HAMRAH study, a population-based prospective study designed to assess the prevalence of traditional cardiovascular risk factors and their changes through a 10-year follow-up. 2228 (61% female) adults aged between 30 and 75 years old and with no overt cardiovascular diseases were selected through a multistage cluster randomized sampling. Blood levels of thyroid-stimulating hormone (TSH), thyroxin (T4), and triiodothyronine (T3) were measured with the aim of assessing the prevalence of abnormal thyroid function status among the modern urban Iranian population, and in order to report the total prevalence of participants with clinical hypo- or hyperthyroidism, the number of individuals taking thyroid-related drugs were added to the ones with overt thyroid dysfunction. A subgroup analysis was also performed to determine the associated risk factors of thyroid dysfunction. RESULTS: The prevalence of thyroid dysfunction among the total population was 7% (95%CI: 5.9 - 8%) and 0.4% (95% CI: 0.1 - 0.6%) for subclinical and overt hypothyroidism, and 1.6% (95% CI: 1 - 2%) and 0.2% (95% CI: 0 - 0.3%) for subclinical and overt hyperthyroidism, respectively. Clinical thyroid dysfunction was detected in 10.3% of the study population (9.4% had clinical hypo- and 0.9% had clinical hyperthyroidism). In the subgroup analysis, thyroid dysfunction was significantly more prevalent among the female participants (P-value = 0.029). CONCLUSIONS: In the current study, the prevalence of different categories of abnormal thyroid status, and also the rate of clinical hypo- and hyperthyroidism was assessed using the data collected from the first phase of the HAMRAH Study. In this study, we detected a higher prevalence of clinical and subclinical hypothyroidism among the Iranian population compared to the previous studies.

Autoimmune thyroid status in subclinical thyroid disorders in patients attending a tertiary care center in Nepal: a hospital-based cross-sectional study.

BACKGROUND: Thyroid dysfunction is the leading endocrine disorder worldwide. Iodine deficiency disorders, which were once the major etiology of thyroid dysfunctions, now have been succeeded by autoimmune thyroid diseases with the rise in aberrant salt ionization protocols. This study endeavors to access the level of thyroid autoantibodies viz. anti-thyroid peroxidase (anti-TPO), anti-thyroglobulin (TGA), and anti-thyroid stimulating hormone receptor (TRAb) in individuals with subnormal thyroid profiles. METHODS: This hospital-based cross-sectional study was conducted at the Department of Clinical Biochemistry, Tribhuvan University for a period of six months. Using non-probability (purposive) sampling method, a total of 60 patients were enrolled with subnormal thyroid profiles to include the population who have not yet started medication. Thyroid hormones (free T3, free T4, TSH) and thyroid antibodies (anti-TPO, TGA, and TRAb) were measured. For non-parametric data, Chi-square test and Kruskal-Wallis test were used. Spearman's correlation was done to determine the association between variables. RESULTS: Out of 60 participants, the majority of the population between 25 and 44 years were diagnosed with thyroid dysfunction with female preponderance. Among all, 40% (n = 24) had subclinical hyperthyroid states while, 60% (n = 36) had subclinical hypothyroid states, and 75% (n = 45) of the total exhibited positive thyroid antibodies. In subclinical hypothyroid patients with TSH above 10 µIU/ml, anti TPO (58.5%) and TGA (66.7%) positivity were highly prevalent. On the other hand, TRAb was exclusively positive in hyperthyroid condition (50% among the group) which is by far the first of its kind reported in Nepal. CONCLUSION: The rise in autoimmune thyroid disease among the Nepalese population infers that addressing iodine deficiency simply through salt iodinization may not be adequate to deal with the rising burden of thyroid disorders, especially in iodine-depleted areas. Also, the increasing prevalence of thyroid autoantibodies positivity in subclinical hypothyroidism in the Nepalese population accounts for the arduous screening and monitoring of autoimmune thyroid disorders in Nepal.

The Incidence of Graves' Hyperthyroidism Before and After COVID-19 Messenger RNA Vaccination.

OBJECTIVE: Case reports of postvaccine early-onset Graves' hyperthyroidism (PVGD) after the administration of COVID-19 vaccination have emerged. Our aim was to investigate whether the incidence of Graves' hyperthyroidism (GD) has increased after the introduction of COVID-19 vaccination. METHODS: We compared the incidence of new-onset GD at a single academic center during 2 periods: December 2017 to October 2019 and December 2020 to October 2022, ie, before and after the implementation of COVID-19 vaccinations. We defined PVGD as laboratory-confirmed hyperthyroidism and GD within 4 weeks after the vaccination or clear onset of symptoms of thyrotoxicosis within 4 weeks of vaccination with evidence of hyperthyroidism and GD within 3 months. RESULTS: During the prevaccination period, 803 patients carried diagnoses of GD, and of these, 131 were new. During the postvaccination period, 901 patients carried diagnoses of GD, and of these, 138 were new. There was no statistically significant difference in the incidence of GD (P = .52), age at onset, gender, or race between the 2 groups. Twenty-four of 138 newly diagnosed patients in the post-COVID-19 group met the criteria for PVGD. The median free T4 was higher, but this was not statistically significant (3.9 vs 2.5 ng/dL, P = .05). There were no differences in age, gender, race, antibody titers, or type of vaccination between PVGD and controls. CONCLUSION: There was no increase in new-onset GD after COVID-19 vaccination. Median free T4 was higher in patients with PVGD, but this was not statistically significant.

Gender variations in the impact of hyperuricemia on thyroid disorders.

This study aimed to examine the impact of hyperuricemia on various thyroid disorders with emphasized focus on differences resulting from different genders. 16094 adults aged ≥18 years were enrolled in this cross-sectional study using a randomized stratified sampling strategy. Clinical data including thyroid function and antibodies, uric acid, and anthropometric measurements were measured. Multivariable logistic regression was used to determine the association between hyperuricemia and thyroid disorders. Women who have hyperuricemia are at a significantly increased risk of developing hyperthyroidism. Women's risk of overt hyperthyroidism and Graves' disease may be markedly increased by hyperuricemia. Men with hyperuricemia did not differ significantly in their chance of acquiring any thyroid disorders.