Clinical review: Thyroid dysfunction and effects on coagulation and fibrinolysis: a systematic review

Thyroid impairment and male fertility: a narrative review of literature

PURPOSE

To evaluate the effect of thyroid function on male fertility, focusing on hypo- and hyperthyroidism.

METHODS

A PubMed/MEDLINE, Web of Science, and Scopus research was performed. Original studies in English published online up to 31 May 2023 were selected and reviewed. The final reference list was defined based on the relevance of each paper to the scope of this review.

RESULTS

The available data in animals (31 studies) and human (26 studies) showed conflicting results. However, thyroid dysfunction altered erection and ejaculation both in animal models than in men.

CONCLUSION

Both hypothyroidism and hyperthyroidism seem to cause ejaculation and erectile dysfunction. Hence, Guidelines recommend against the systematic screening for thyroid disorders in the men in sub-fertile couples, but only in men with ejaculation and erectile dysfunction and/or altered semen parameters.

Cerebral Venous Sinus Thrombosis Associated With Subclinical Hypothyroidism: A Case Report and Literature Review

Thyroid dysfunction is a well-known cause of cerebral venous sinus thrombosis (CVST), but most reports have focused on CVST associated with hyperthyroidism, with only a few mentioning CVST associated with hypothyroidism. Subclinical hypothyroidism, characterized by thyroid hormone levels within reference values but elevated thyroid-stimulating hormone, can also cause CVST. Here, we present a case of CVST associated with subclinical hypothyroidism. A 48-year-old man with headache, nausea, and left-sided motor weakness was admitted to our hospital, with a history of economy-class syndrome. Magnetic resonance imaging revealed occlusion of the superior sagittal sinus, right transverse sinus, and right sigmoid sinus. Digital subtraction angiography (DSA) confirmed CVST from the right common carotid artery, revealing abnormal staining of the thyroid gland. The patient was serologically in a state of subclinical hypothyroidism. Consequently, the patient was diagnosed with CVST associated with subclinical hypothyroidism. Anticoagulation therapy was initiated shortly after admission. CVST gradually resolved, and the affected sinuses were recanalized. Paraplegia improved, and the patient was discharged home 19 days after admission with a modified Rankin scale of 1. Subclinical hypothyroidism can induce CVST, underscoring the importance of screening for thyroid function in CVST patients, even without apparent thyroid dysfunction symptoms. DSA findings are valuable for diagnosing thyroid disease.

Thyroid storm-induced acute liver dysfunction and portal hypertension in a patient with Graves' disease: a case report

Thyroid storm is a life-threatening condition associated with multiorgan dysfunction and decompensation. We report the case of a 41-year-old woman having Graves' disease presented with thyroid storm complicated with liver dysfunction and portal hypertension in the absence of congestive heart failure or known liver disease. After successful therapeutic management, all biological, clinical and morphological abnormalities regressed.

Conservative management of a rare case of post thyroidectomy tracheal injury with coagulation abnormalities

Background

Tracheal injury is a rare but potentially serious acute complication of endotracheal intubation. Very few cases of tracheal injury associated with coagulation abnormalities have been reported in the literature. We present a rare case of a patient presenting with tracheal injury in combination with coagulation abnormalities following thyroidectomy.

Case presentation

A 58-year-old woman with a history of postoperative chemotherapy for breast cancer, gastric polyps, multiple colonic polyps, esophageal papillary adenomas, and thyroid adenomas presented with dyspnea following 10 ml hemoptysis on the third day after thyroidectomy; she was admitted to the intensive care unit and underwent tracheal intubation for maintaining the airway. Subsequent bronchoscopy revealed a nodular red neoplasm 5-cm from the carina in the trachea obstructing part of the lumen, with a small amount of fresh hemorrhage on the surface. Tracheal injury was considered the preliminary diagnosis. Fiberoptic bronchoscope guided tracheal intubation helped prevent rupture of the tumor, and the cannula was properly inflated to arrest the bleeding while blocking the lower part of the trachea. An emergency surgical evacuation of the cervical hematoma was performed for managing postoperative bleeding. The patient demonstrated persistent pancytopenia despite frequent transfusions. Laboratory examination results revealed abnormal coagulation parameters, anemia, and hepatic dysfunction. Following a multidisciplinary team discussion, pituitrin for hemostasis, tranexamic acid for strengthening hemostasis treatment, and nutritional support and anti-infection treatment were initiated. Endotracheal tube cuff inflation was performed to compress the bleeding site. Complete resolution of the subcutaneous hematoma was observed nine days after the tracheal injury; bronchoscopy revealed residual ecchymosis in the airway hematoma with no evidence of obstruction.

Conclusion

Conservative management of tracheal injury limited to the mucosa or submucosa without significant amount of active bleeding using endotracheal intubation is considered a practical and effective approach. Successful management was ensured by appropriate clinical suspicion, early multidisciplinary team discussion, and prompt diagnosis and interventions.

Association Between Nonthyroidal Illness Syndrome and Disseminated Intravascular Coagulation in Sepsis

Purpose

Both nonthyroidal illness syndrome (NTIS) and disseminated intravascular coagulation (DIC) are commonly occurred in sepsis. The objective of this study is to evaluate the association between NTIS and DIC, as well as their impacts on the mortality in adults with sepsis.

Patients and methods

A total of 1219 septic patients in two Chinese academic centers from October 2012 and October 2022 were enrolled in analysis. We conduct logistic regression models to analyze the independent risk factors for DIC. Modified Poisson regression models are used to estimate the relative risk (RR) of NTIS on the 28 days mortality in septic patients with DIC. Correlation analysis between thyroid function parameters and coagulation parameters is performed with Pearson coefficient be reported.

Results

DIC is diagnosed on 388 (31.8%) of all the 1219 enrolled septic patients within 72 hours after admission. In multivariate logistic regression models, NTIS (OR 3.19; CI 2.31-4.46; p<0.001) is a statistically significant independent risk factor for DIC after adjustment for potential confounders. Twenty-eight days mortality is significantly higher in DIC patients complicated with NTIS compared with the other DIC patients (23.2% vs 14.0%, p=0.024). This result is also robust in different modified Poisson regression models (Model 1: RR 1.46; CI 1.25-1.70; p<0.001; Model 2: RR 1.35; CI 1.14-1.60; p<0.001; Model 3: RR 1.18; CI 1.02-1.37; p=0.026). Correlation analysis reveals that the thyroid function parameters of FT3, FT4 and TSH only have weak correlations with coagulation parameters of platelet count, fibrinogen, FDP, D-dimers, PT, APTT and INR in sepsis.

Conclusion

NTIS is an independent risk factor for DIC in adults with sepsis. DIC patients complicated with NTIS have significantly higher severity and higher rate of mortality.

Hypothyroidism as an Independent Predictor of 30-day Readmission in Head and Neck Cancer Patients

OBJECTIVES

To define the role of hypothyroidism and other risk factors for unplanned readmissions after surgery for head and neck cancer.

STUDY DESIGN

Retrospective cohort study.

METHODS

The Nationwide Readmission Database (NRD) was used to identify patients who underwent surgery for mucosal head and neck cancer (oral cavity, oropharynx, larynx, and hypopharynx) between 2010 and 2017. Univariate and multivariate logistic regression were performed to determine patient, tumor, and hospital related risk factors for 30-day readmission. Readmitted patients were stratified by preoperative diagnosis of hypothyroidism to compare readmission characteristics.

RESULTS

For the 131,013 patients who met inclusion criteria, the readmission rate was 15.9%. Overall, 11.91% of patients had a preoperative diagnosis of hypothyroidism. After controlling for other variables, patients with a preoperative diagnosis of hypothyroidism had 12.2% higher odds of readmission compared to those without hypothyroidism (OR: 1.12, 1.03-1.22, p = 0.008). Patients with hypothyroidism had different reasons for readmission, including higher rates of wound dehiscence, fistula, infection, and electrolyte imbalance. Among readmitted patients, the length of stay for index admission (mean 10.5 days vs. 9.2 days, p < 0.001), readmission (mean 7.0 vs. 6.6 days, p = 0.05), and total hospital charge were higher for hypothyroid patients ($137,742 vs. $119,831, p < 0.001).

CONCLUSION

Hypothyroidism is an independent risk factor for 30-day readmission following head and neck cancer resection. Furthermore, hypothyroid patients are more likely to be readmitted for wound complications, infection, and electrolyte imbalance. Targeted interventions should be considered for hypothyroid patients to decrease readmission rates and associated patient morbidity, potentially leading to earlier initiation of adjuvant treatment.

LEVEL OF EVIDENCE

3 Laryngoscope, 133:2988-2998, 2023.

Subclinical Hypothyroidism, Kidney, and Heart from Normal to Uremic Milieu

Thyroid hormone (TH) imbalances, particularly subclinical hypothyroidism (SCHT), are associated with chronic kidney disease (CKD) and end-stage kidney disease (ESKD). SCHT is more prevalent in CKD and ESKD patients than in the general population, and this condition increases the risk of cardiovascular disease (CVD) morbidity and mortality. The risk of CVD is higher in CKD and ESKD patients compared with the general population. Traditional and nontraditional risk factors, including TH abnormalities, contribute to the high CVD burden in CKD and ESKD patients. The review discusses the link between CKD and hypothyroidism, with a focus on SCHT, and the mechanisms that lead to CVD burden.

Cerebral Sinus Vein Thrombosis and Gender: A Not Entirely Casual Relationship

Cerebral sinus venous thrombosis (CSVT) is a relatively rare acute disorder of cerebral circulation, but it can potentially be associated with serious sequelae and a poor prognosis. The neurological manifestations associated with it are often not adequately taken into consideration given the extreme variability and nuances of its clinical presentation and given the need for radiological methods suitable for this type of diagnosis. CSVT is usually more common in women, but so far there are little data available in the literature on sex-specific characteristics regarding this pathology. CSVT is the result of multiple conditions and is therefore to be considered a multifactorial disease where at least one risk factor is present in over 80% of cases. From the literature, we learn that congenital or acquired prothrombotic states are to be considered extremely associated with the occurrence of an acute episode of CSVT and its recurrences. It is, therefore, necessary to fully know the origins and natural history of CSVT, in order to implement the diagnostic and therapeutic pathways of these neurological manifestations. In this report, we summarize the main causes of CSVT considering the possible influence of gender, bearing in mind that most of the causes listed above are pathological conditions closely linked to the female sex.

The Effects of Chronic Steroid Use on Postoperative Complications Following Thyroidectomy

BACKGROUND

Patients undergoing thyroidectomy are sometimes on chronic steroids for underlying disease. This study examined the postoperative risk profile of thyroidectomy patients on chronic steroids.

METHODS

Patients in the National Surgical Quality Improvement Program (NSQIP) database who underwent thyroidectomy were sorted by presence or absence of chronic steroid use. Clinicodemographics, comorbidities, and postoperative complications were recorded and compared between the two. Univariate and multivariate analyses compared the groups and calculated odds ratios (OR).

RESULTS

We identified 42,857 patients. 41,903 (97.8%) patients were not on chronic steroids, while 954 (2.2%) were. Most underwent total thyroidectomy (18,748, 43.75%) or total lobectomy (16,323, 38.09%). Following univariate and multivariate analyses, patients on chronic steroids had increased risk of postoperative bleeding and transfusions (OR = 0.375, p = 0.046, 95% CI 0.223-0.988), open wound infection (OR = 0.226, p < 0.001, 95% CI 0.117-0.437), pulmonary embolism (OR = 0.312, p = 0.034, 95% CI 0.106-0.918), and ventilator use > 48 h (OR = 0.401, p < 0.008, 95% CI 0.205-0.785).

CONCLUSIONS

Chronic steroid use prior to thyroidectomy is an independent risk factor for multiple postoperative complications, namely postoperative bleeding and transfusions, open wound infection, pulmonary embolism, and ventilator use over 48 h. Patients on chronic steroids should be medically optimized before thyroidectomy to reduce the risk of potentially life-threatening complications.

Congenital hypothyroidism: a case report of an Egyptian child with congenital heart disease, pelvic kidney and cavernous transformation of portal vein

Background

A case of thyroid hormone deficiency which presented at birth. Thyroid hormones are essential for brain development and normal cognitive function. Common symptoms of congenital hypothyroidism (CH) include constipation, decreased activity, increased sleep and feeding difficulty. Common signs include dry skin, macroglossia and umbilical hernia. If congenital hypothyroidism is left untreated after birth, it can lead to permanent intellectual disability and growth failure.

Case presentation.

Here, we report a 10.5-year-old female with the typical features of CH. She is the sixth in order of birth of consanguineous Egyptian parents. No family history of similar condition. Our patient had primary CH caused by thyroid agenesis. She had congenital heart disease, pelvic kidney, cavernous transformation of portal vein and parenchymatous liver disease.

Conclusions

Congenital hypothyroidism is associated with an elevated risk of congenital anomalies. Clinical suspicion of symptoms and signs of congenital hypothyroidism are important for early diagnosis and prevention of serious problems that are related to congenital hypothyroidism.

Takotsubo cardiomyopathy with left ventricle thrombus caused by subacute thyroiditis

We report a rare case of takotsubo cardiomyopathy caused by subacute thyroiditis in a man in his 50s. He went to the doctor with complaints of loss of appetite, diarrhoea, chills and general malaise. He had consciousness disturbance, thyrotoxicosis and thyroid-stimulating hormone (TSH) suppression. Thyroglobulin and C reactive protein levels in the blood were elevated, but TSH receptor antibody, thyroid-stimulating antibody, antithyroglobulin antibody and antithyroid peroxidase antibody were not. We began treatment with prednisolone and propranolol after he was diagnosed with thyroid storm caused by subacute thyroiditis. The ECG revealed inverted T waves on the fifth day after admission. He was newly diagnosed with takotsubo cardiomyopathy on the day. A large thrombus was detected in the left ventricle, requiring anticoagulation therapy. Thus, even if there are no findings of takotsubo cardiomyopathy or thrombus at the onset of thyroid storm, appropriate monitoring is required because they can develop during the treatment course.

Fluctuations in Thyroid Hormone Levels During Initial Treatment for Differentiated Thyroid Carcinoma are Associated with Changes in Hemostasis: A Prospective Cohort Study

Background: During treatment for differentiated thyroid carcinoma (DTC), patients go from euthyroidism to severe hypothyroidism to subclinical hyperthyroidism induced by thyroid hormone suppression therapy (THST). Severe hypothyroidism may induce a tendency toward bleeding, whereas hyperthyroidism is thrombogenic. Therefore, treatment for DTC may increase the risk of bleeding during thyroid hormone withdrawal, and thrombosis during THST. This study aims to provide prospective analysis of changes in the hemostatic system from euthyroidism to hypothyroidism, and during THST, in patients treated for DTC. Methods: This is a secondary study in a larger Dutch prospective cohort. Consecutive samples were obtained from 20 patients (18 female [90%]; median age 48 [interquartile range 35.8-56.5] years) throughout their treatment for DTC during euthyroidism (n = 5), severe hypothyroidism (n = 20), and THST (n = 20). We measured selected hemostatic proteins and C-reactive protein (CRP), performed functional tests of hemostasis (a thrombin generation test and a plasma-based clot lysis test), and assessed markers of in vivo activation of hemostasis (thrombin-antithrombin complexes, plasmin-antiplasmin [PAP] complexes, and D-dimer levels). Results: During hypothyroidism, the majority of measured parameters did not change. During THST, plasma levels of nearly all measured hemostatic proteins were higher than during hypothyroidism. Additionally, CRP significantly increased from 1.3 (0.5-3.3) to 3.2 (1.3-5.1) mg/L during THST (p < 0.01). Ex vivo thrombin generation increased from 626.0 (477.0-836.3) to 876.0 (699.0-1052.0) nM × min (p = 0.02), and ex vivo clot lysis time increased from 60.6 (55.6-67.4) to 76.0 (69.7-95.0) minutes during THST (p < 0.01). PAP levels reduced from 266.5 (211.8-312.0) to 192.0 (161.0-230.0) μg/L during THST (p < 0.01); other markers of in vivo activation of coagulation remained unaffected. Conclusions: During THST-induced hyperthyroidism, a shift toward a more hypercoagulable and hypofibrinolytic state occurred. However, in vivo activation of hemostasis did not increase. The rise in CRP levels suggests the presence of a low-grade inflammation in patients during THST. Both a hypercoagulable and hypofibrinolytic state and a low-grade inflammation are associated with an increased risk of cardiovascular diseases (CVD). Therefore, the subtle changes found during THST could potentially play a role in the pathogenesis of CVD as observed in DTC patients. Clinical Trial Registration: This study is part of a larger clinical trial registered at the Netherlands Trial Register (NTR ID 7228).

Association between hyperthyroidism and thromboembolism: A retrospective observational study

Background

Thyroid gland diseases are a common health problem worldwide. Increase of thyroid gland hormones can cause numerous conditions that range from mild cases to life-threatening diseases. Hyperthyroidism is not a common risk factor for venous thrombosis (VT), many studies found a relation between hyperthyroidism and thromboembolism.

Objectives

We sought to detect any changes in thyroid-stimulating hormone (TSH), and free T4 value associated with the occurrence of Deep vein thrombosis (DVT), pulmonary embolism (PE), and cerebral VT.

Methodology

An observational retrospective review of outpatients' records in King Abdulaziz Medical City in Riyadh from January 2018 to March 2020 includes all patients with hyperthyroidism, patients who are bedridden, recent surgeries, and those on oral contraceptives pills or on anticoagulants were excluded from the study. All symptomatic VT cases are objectively confirmed.

Results

Three hundred patients were recognized, of whom most were female (80%), whereas (20%) were male, mean age in identified patients was (42.3 ± 14.5 years; range, 18-80 years). Of all patients, 3 (1%) patients had DVTs, equally 3 (1%) patients had PE, and 2 (0.7%) patients had cerebral embolism. TSH level has a significant association with the overall risk of DVT, PE, and cerebral embolism. In the FT₄ level, there was a significant association with the risk of DVT and PE but not with cerebral embolism.

Conclusions

The literature indicates a significantly associated between the development of VT and hyperthyroidism. Furthermore, the data support that hyperthyroidism is considered an additional risk factor for VT.

Hypothyroidism and Spine Surgery: a Review of Current Findings

PURPOSE OF REVIEW

Hypothyroidism is a common medical comorbidity and has been linked to adverse surgical outcomes. However, its effect on spine surgery outcomes is less clear. The aim of this review is to compile current literature to serve as a guide for spine surgeons when treating patients with hypothyroidism.

RECENT FINDINGS

In both the cervical and lumbar spine, patients with hypothyroidism are at increased risk of postoperative medical complications. Consequently, patients with hypothyroidism experience increased healthcare costs and readmission rates. However, there are some contradictory findings with some studies suggesting that hypothyroidism may have a protective effect in patients undergoing lumbar fusion, specifically against postoperative myocardial infraction and decreased inpatient mortality. When examining spine surgery outcomes, there are mixed results when considering the effect of hypothyroidism. Some studies have shown increased medical complications, hardware failure, and increased expenditure; however, other recent findings suggest possible protective effects. Future studies are needed to help create concrete guidelines for treating patients with hypothyroidism.

Two Cases of Thyrotoxicosis and Euglycemic Diabetic Ketoacidosis Under Sodium-glucose Transport Protein 2 Inhibitor Treatment

Thyrotoxicosis and sodium-glucose transport protein 2 inhibitors (SGLT2is) are associated with the induction of euglycemic diabetic ketoacidosis (euDKA). We herein report two cases of euDKA in patients with diabetes mellitus wherein both thyrotoxicosis and SGLT2i treatment were the underlying causes. One patient developed thyrotoxicosis during the course of type 2 diabetes mellitus, whereas the other patient was suspected of developing slowly progressive insulin-dependent diabetes mellitus during the course of Graves' disease. Although such cases are rare, there is some concern that similar cases may occur because of the increased frequency of SGLT2i use in recent years.

Prolonged APTT and autoimmune overt hypothyroidism identified postpartum: a case report

INTRODUCTION

Thyroid disorders have been linked to abnormalities in the coagulation system, and a hypocoagulant state has been proposed in hypothyroidism. The assessment of thyroid function is, however, not routinely recommended as part of the assessment for coagulation disorders.

CASE PRESENTATION

We present a 32-year-old woman who had no history of thyroid disease and who recently gave birth preterm because of severe preeclampsia and intrauterine growth restriction. Due to severe placental dysfunction, she underwent a routine biochemical assessment of the coagulation system 6 months postpartum, and a prolonged activated partial thromboplastin time (APTT) (43 s) was identified along with a low level of coagulation factor VIII (0.44 IU/mL), and a low level of von Willebrand factor (vWF) antigen (0.35 IU/mL), vWF activity (0.38 IU/mL) as well as reduced generation of thrombin. The assessment of thyroid function in the patient identified autoimmune, overt hypothyroidism with a thyroid-stimulating hormone (TSH) concentration of 139 mIU/L, low levels of the peripheral thyroid hormones (total thyroxine: 43 nmol/L, total triiodothyronine: 0.9 nmol/L), and high levels of thyroid peroxidase antibodies (296 U/mL) as well as thyroglobulin antibodies (927 U/mL).

CONCLUSION

In this case, prolonged APTT provided a diagnostic clue for the assessment of thyroid function in a young woman with a recent history of severe placental dysfunction. The identification of autoimmune, overt hypothyroidism emphasizes that measurement of TSH may be of clinical importance in cases of unexplained prolonged APTT or other biochemical signs of abnormalities in the coagulation system.

ESTABLISHED FACTS

Hypothyroidism has been associated with alterations of the coagulation system suggesting a hypocoagulant state. At present, measurement of thyroid-stimulating hormone is not routinely recommended as part of the assessment for coagulation disorders.

NOVEL INSIGHTS

In this case, biochemical assessment of the coagulation system was routinely performed following a pregnancy complicated by severe placental dysfunction. Overt hypothyroidism of autoimmune origin was identified secondary to prolonged activated partial thromboplastin time (APTT) postpartum along with low levels of coagulation factor VIII, von Willebrand factor, and thrombin generation. Measurement of thyroid-stimulating hormone may be considered in cases of unexplained prolonged APTT.

Thyroid disorders and cardiovascular manifestations: an update

Cardiovascular disease (CVD) remains the leading cause of death worldwide, representing a major health, social, and economic issue. Thyroid disorders are very common and affect >10% of the adult population in total. The aim of this review is to describe the physiologic role of thyroid hormones on cardiovascular system, to present cardiovascular manifestations in patients with thyroid disorders, emphasizing in molecular mechanisms and biochemical pathways, and to summarize current knowledge of treatment options. Thyroid hormone receptors are located both in myocardium and vessels, and changes in their concentrations affect cardiovascular function. Hyperthyroidism or hypothyroidism, both clinical and subclinical, without the indicated therapeutical management, may contribute to the progression of CVD. According to recent studies, even middle changes in thyroid hormones levels increase cardiovascular mortality from 20% to 80%. In more details, thyroid disorders seem to have serious effects on the cardiovascular system via plenty mechanisms, including dyslipidemia, hypertension, systolic and diastolic myocardial dysfunction, as well endothelial dysfunction. On top of clinical thyroid disorders management, current therapeutics focus on younger patients with subclinical hypothyroidism and elderly patients with subclinical hyperthyroidism.

Endocrine system dysfunction and chronic heart failure: a clinical perspective

Chronic heart failure (CHF) leads to an excess of urgent ambulatory visits, recurrent hospital admissions, morbidity, and mortality regardless of medical and non-medical management of the disease. This excess of risk may be attributable, at least in part, to comorbid conditions influencing the development and progression of CHF. In this perspective, the authors examined and described the most common endocrine disorders observed in patients with CHF, particularly in individuals with reduced ejection fraction, aiming to qualify the risks, quantify the epidemiological burden and discuss about the potential role of endocrine treatment. Thyroid dysfunction is commonly observed in patients with CHF, and sometimes it could be the consequence of certain medications (e.g., amiodarone). Male and female hypogonadism may also coexist in this clinical context, contributing to deteriorating the prognosis of these patients. Furthermore, growth hormone deficiency may affect the development of adult myocardium and predispose to CHF. Limited recommendation suggests to screen endocrine disorders in CHF patients, but it could be interesting to evaluate possible endocrine dysfunction in this setting, especially when a high suspicion coexists. Data referring to long-term safety and effectiveness of endocrine treatments in patients with CHF are limited, and their impact on several "hard" endpoints (such as hospital admission, all-cause, and cardiovascular mortality) are still poorly understood.

Association of longitudinal trends in thyroid function with incident carotid atherosclerosis in middle-aged and older euthyroid subjects: the Tianjin Chronic Low-Grade Systemic Inflammation and Health (TCLSIH) cohort study

BACKGROUND

Previous studies have posited that an association exists between thyroid function and the heart and vasculature. It remains unclear, however, whether longitudinal trends in thyroid function contribute to the development of atherosclerosis. We conducted a cohort study to examine the association of longitudinal trends in thyroid function with incident carotid atherosclerosis (CA) in middle-aged and older euthyroid subjects.

METHODS

This cohort study's participants were recruited from the Tianjin Chronic Low-grade Systemic Inflammation and Health Cohort Study in Tianjin, China. Free triiodothyronine (FT3), thyroxine (FT4) and thyroid-stimulating hormone (TSH) were measured using chemiluminescence immunoassay. CA was assessed using carotid ultrasonography. Thyroid function and ultrasonography were assessed yearly during follow-up. Multivariable Cox proportional hazards regression models were used to assess the association between thyroid function and incident CA.

RESULTS

A total of 3,181 participants were enrolled in the cohort study. Within 7,762 person-years of follow-up, 944 participants developed CA, the incidence rate of CA was 122 per 1,000 person-years. The fully adjusted hazards ratios (95% confidence interval) of CA for per 1-unit increase in changes of FT3, FT4 and TSH were 1.34(1.22-1.47), 1.22(1.19-1.26) and 0.92 (0.77-1.09) (P < 0.0001, <0.0001 and = 0.32, respectively), respectively. Similar significant associations between mean levels of FT3 and FT4 and incident CA were observed. However, baseline thyroid function was not associated with incident CA.

CONCLUSIONS

These findings suggest that higher mean levels and higher values of changes in thyroid hormones were associated with a higher risk of incident CA in middle-aged and older euthyroid subjects.

Thyroid Hormone Therapy and Incident Stroke

CONTEXT

Stroke is a leading cause of death and disability and there is a need to identify modifiable risk factors.

OBJECTIVE

We aimed to determine the relationship between thyroid hormone treatment intensity and incidence of atrial fibrillation and stroke.

METHODS

We conducted a retrospective cohort study using data from the Veterans Health Administration between 2004 and 2017, with a median follow-up of 59 months. The study population comprised 733 208 thyroid hormone users aged ≥18 years with at least 2 thyroid stimulating hormone (TSH) measurements between thyroid hormone initiation and incident event (atrial fibrillation or stroke) or study conclusion (406 030 thyroid hormone users with at least 2 free thyroxine [T4] measurements).

RESULTS

Overall, 71 333/643 687 (11.08%) participants developed incident atrial fibrillation and 41 931/663 809 (6.32%) stroke. In multivariable analyses controlling for pertinent factors such as age, sex, and prior history of atrial fibrillation, higher incidence of stroke was associated with low TSH or high free T4 levels (ie, exogenous hyperthyroidism; eg, TSH <0.1 mIU/L; OR 1.33; 95% CI, 1.24-1.43; free T4>1.9 ng/dL, OR 1.17, 95% CI 1.06-1.30) and high TSH or low free T4 levels (ie, exogenous hypothyroidism; eg, TSH >5.5 mIU/L; OR 1.29; 95% CI, 1.26-1.33; free T4 <0.7 ng/dL; OR 1.29; 95% CI, 1.22-1.35) compared with euthyroidism (TSH >0.5-5.5 mIU/L and free T4 0.7-1.9 ng/dL). Risk of developing atrial fibrillation and stroke was cumulative over time for both patients with exogenous hyperthyroidism and hypothyroidism.

CONCLUSION

Both exogenous hyper- and hypothyroidism were associated with increased risk of stroke, highlighting the importance of patient medication safety.

Incidence and Clinical Outcomes of Hypothyroidism in Patients Undergoing Spinal Fusion

Background

Hypothyroidism has been independently associated with the development of several comorbidities and is known to increase complication rates in non-spinal surgeries. However, there are limited data regarding the effects of hypothyroidism in major spine surgery. Therefore, we present the largest retrospective analysis evaluating outcomes in hypothyroid patients undergoing spinal fusion.

Methods

A retrospective review of the National Inpatient Sample (NIS) from 2004-2014 was performed. Patients with an International Classification of Diseases, 9th revision, Clinical Modification (ICD-9-CM) procedure code indicating spinal fusion (81.04-81.08, 81.34-81.38, 81.0x, 81.3x) were included. Patients with an ICD-9-CM diagnosis code indicating hypothyroidism (244.x) were compared to those without. Cervical and lumbar fusions were evaluated independently. Significant covariates in univariable logistic regression were utilized to construct multivariable models to analyze the effect of hypothyroidism on perioperative morbidity and mortality.

Results

A total of 4,149,125 patients were identified, of which 9.4% were hypothyroid. Although, hypothyroid patients had a higher risk of hematologic complications (lumbar - odds ratio [OR] 1.176, p < 0.0001; cervical - OR 1.162, p < 0.0001), they exhibited decreased in-hospital mortality (lumbar - OR .643, p < 0.0001; cervical - OR .606, p < 0.0001). Hypothyroid lumbar fusion patients also demonstrated decreased rates of perioperative myocardial infarction (MI) (OR .851, p < 0.0001). All these results were independent of patient gender.

Conclusions

Hypothyroid patients undergoing spinal fusion demonstrated lower rates of inpatient mortality and, in lumbar fusions, also had lower rates of acute MI when compared to their euthyroid counterparts. This suggests that hypothyroidism may offer protection against all-cause mortality and may be cardioprotective in the postoperative period for lumbar spinal fusions independent of patient gender.

COVID-19 and the Endocrine System: A Comprehensive Review on the Theme

Background and aim. The review aimed to summarize advances in the topic of endocrine diseases and coronavirus disease 2019 (COVID-19). Methods. Scientific and institutional websites and databases were searched and data were collected and organized, when plausible, to angle the discussion toward the following clinical issues. (1) Are patients with COVID-19 at higher risk of developing acute or late-onset endocrine diseases or dysfunction? (2) May the underlying endocrine diseases or dysfunctions be considered risk factors for poor prognosis once the infection has occurred? (3) Are there defined strategies to manage endocrine diseases despite pandemic-related constraints? Herein, the authors considered only relevant and more frequently observed endocrine diseases and disorders related to the hypothalamic-pituitary region, thyroid and parathyroid glands, calcium-phosphorus homeostasis and osteoporosis, adrenal glands, and gonads. Main. Data highlight the basis of some pathophysiological mechanisms and anatomical alterations of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2)-induced endocrine dysfunctions. Some conditions, such as adrenal insufficiency and cortisol excess, may be risk factors of worse clinical progression once the infection has occurred. These at-risk populations may require adequate education to avoid the SARS-CoV-2 infection and adequately manage medical therapy during the pandemic, even in emergencies. Endocrine disease management underwent a palpable restraint, especially procedures requiring obligate access to healthcare facilities for diagnostic and therapeutic purposes. Strategies of clinical triage to prioritize medical consultations, laboratory, instrumental evaluations, and digital telehealth solutions should be implemented to better deal with this probably long-term situation.

The interrelationship between pregnancy, venous thromboembolism, and thyroid disease: a hypothesis-generating review

Pregnancy induces physiological changes that affect the risk of thrombosis and thyroid disease. In this hypothesis-generating review, the physiological changes in the coagulation system and in thyroid function during a normal pregnancy are described, and the incidence of venous thromboembolism (VTE) and thyroid disease in and after a pregnancy are compared and discussed. Furthermore, evidence regarding the association between thyroid disease and VTE in non-pregnant individuals is scrutinized. In conclusion, a normal pregnancy entails hormonal changes, which influence the onset of VTE and thyroid disease. Current evidence suggests an association between thyroid disease and VTE in non-pregnant individuals. This review proposes the hypothesis that maternal thyroid disease associates with VTE in pregnant women and call for future research studies on this subject. If an association exists in pregnant women specifically, such findings may have clinical implications regarding strategies for thyroid function testing and potential thromboprophylaxis in selected individuals.

Severe Prekallikrein Deficiency Associated with Low Level of Factor XII: A Case Report

Hereditary deficiency of plasma prekallikrein (PPK) is a rare autosomal recessive disease. The affected patients are often asymptomatic and diagnosed incidentally during preoperative investigations or during hospitalization by isolated prolongation of activated partial thromboplastin time (aPTT). In this article, we report, a 46-year-old woman who was candidate for two invasive procedures (thyroid FNA and hysterectomy) and underwent preoperative evaluation. Due to prolonged aPTT with normal PT she was referred to the IBTO reference coagulation laboratory for specific coagulation assays. Ultimately, the examinations revealed severe PPK deficiency (<1%) with partial deficiency of factor XII level (25%).

Endovascular management of acute mesenteric ischemia in a young patient with thyrotoxicosis and atrial fibrillation: A case report and review of the literature

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Acute mesenteric ischemia has a high mortality rate of 50%–80%.

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CT angiography is highly valuable in the diagnosis of acute mesenteric ischemia.

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Patients who present with peritonitis or hemodynamic instability should undergo open surgery.

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Endovascular management is increasingly being considered as the main modality of management of AMI in selected cases.

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Endovascular management of AMI involves aspiration thrombectomy, thrombolysis, and/or possible angioplasty and stenting.

Introduction

Acute mesenteric ischemia caused by an embolism resulting from atrial fibrillation in a thyrotoxic young male patient is a rare event. Endovascular intervention is increasingly being considered as the primary modality of treatment in selected patients.

Presentation of case

A 41-years male known to have hyperthyroidism presented with atrial fibrillation, acute mesenteric ischemia, splenic infarction, and left renal infarction. He was successfully managed with endovascular intervention of the superior mesenteric artery.

Discussion

Acute mesenteric ischemia has a high mortality rate. CT angiography is the investigation of choice for diagnosis of the mesenteric vessels occlusion and assessment of bowel ischemia. The clinical presentation guides into the treatment and the choice between open surgery and endovascular intervention as the primary modality of treatment. Thyrotoxicosis is a risky comorbid condition for any procedure to be done, so proper perioperative management is essential to decrease morbidity and mortality.

Conclusion

Prompt diagnosis and management of acute mesenteric ischemia is essential to decrease the morbidity and mortality rates. Endovascular management can be considered as a primary modality of treatment in selected cases.

Thyroid Storm, Rhabdomyolysis, and Pulmonary Embolism: An Unusual Triad Case Report

Introduction: Thyroid storm is a medical emergency associated with significant mortality. Hyperthyroid states have been associated with hypercoagulability as well as rhabdomyolysis. However, the pathophysiology of this association remains under investigation. Case Report: A 62-year-old male patient presented to the emergency department with weakness and was found to have thyroid storm with concurrent submassive pulmonary embolisms and rhabdomyolysis. To our knowledge, this is the first reported presentation of this triad. Conclusion: This case highlights the potentially difficult diagnosis and management of thyroid storm, as well as associated life-threatening complications, including venous thromboemboli and rhabdomyolysis.

Relationship of thyroid dysfunction with cardiovascular diseases: updated review on heart failure progression

Heart disease remains the leading cause of death globally. Heart failure (HF) is a clinical syndrome that results from impairment of the ability of the ventricle to fill with or eject blood. Over the past two decades, accumulated evidence has revealed the contribution of thyroid hormones to cardiovascular (CV) events, exerting their action through genomic and non-genomic pathways within the cardiomyocytes. The pivotal role of thyroid hormones in maintaining cardiac homeostasis has been observed in previous investigations which suggest that the CV system is adversely impacted by fluctuations in thyroid hormone levels, such as those that occur in hypothyroidism, hyperthyroidism, and low triiodothyronine syndrome (LT₃S). Thyroid dysfunction has direct effects on myocardial contractility, systolic and diastolic blood pressure, heart mass, heart rate, ejection fraction, and heart output, which may ultimately lead to HF. Recent clinical data have shown that thyroid hormone replacement therapy for hypothyroid patients appears to provide the potential for reducing CV events. Therefore, this review aims to address the impact of thyroid hormone dysfunction on pathophysiological mechanisms contributing to the development and progression of HF.

Screening for New Markers to Assess Thyroid Hormone Action by OMICs Analysis of Human Samples

Determination of the levels of thyroid-stimulating hormone (TSH) and free thyroid hormones (fTHs) is crucial for assessing thyroid function. However, as a result of inter-individual genetic variability and different environmental factors individual set points exist for TSH and fTHs and display considerable variation. Furthermore, under specific pathophysiological conditions like central hypothyroidism, TSH secreting pituitary tumors, or thyroid hormone resistance the established markers TSH and fTH fail to reliably predict thyroid function and adequate supply of TH to peripheral organs. Even in case of overt hyper- and hypothyroidism circulating fTH concentrations do not correlate with clinical symptoms. Therefore, there is a clear need for novel, more specific biomarkers to diagnose and monitor thyroid function. OMICs screening approaches allow parallel profiling of hundreds to thousands of molecules and thus comprehensive monitoring of molecular alterations in tissues and body fluids that might be associated with changes in thyroid function. These techniques thus constitute promising tools for the identification of urgently needed novel biomarkers. This mini review summarizes the findings of OMICs studies in thyroid research with a particular focus on population-based and patient studies as well as interventional approaches investigating the effects of thyroid hormone administration.

No Dataset Left Behind: Mechanistic Insights into Thyroid Receptor Signaling Through Transcriptomic Consensome Meta-Analysis

Background: Discovery-scale omics datasets relevant to thyroid receptors (TRs) and their physiological and synthetic bioactive small-molecule ligands allow for genome-wide interrogation of TR-regulated genes. These datasets have considerable collective value as a reference resource to allow researchers to routinely generate hypotheses addressing the mechanisms underlying the cell biology and physiology of TR signaling in normal and disease states. Methods: Here, we searched the Gene Expression Omnibus database to identify a population of publicly archived transcriptomic datasets involving genetic or pharmacological manipulation of either TR isoform in a mouse tissue or cell line. After initial quality control, samples were organized into contrasts (experiments), and transcript differential expression values and associated measures of significance were generated and committed to a consensome (for consensus omics) meta-analysis pipeline. To gain insight into tissue-selective functions of TRs, we generated liver- and central nervous system (CNS)-specific consensomes and identified evidence for genes that were selectively responsive to TR signaling in each organ. Results: The TR transcriptomic consensome ranks genes based on the frequency of their significant differential expression over the entire group of experiments. The TR consensome assigns elevated rankings both to known TR-regulated genes and to genes previously uncharacterized as TR-regulated, which shed mechanistic light on known cellular and physiological roles of TR signaling in different organs. We identify evidence for unreported genomic targets of TR signaling for which it exhibits strikingly distinct regulatory preferences in the liver and CNS. Moreover, the intersection of the TR consensome with consensomes for other cellular receptors sheds light on transcripts potentially mediating crosstalk between TRs and these other signaling paradigms. Conclusions: The mouse TR datasets and consensomes are freely available in the Signaling Pathways Project website for hypothesis generation, data validation, and modeling of novel mechanisms of TR regulation of gene expression. Our results demonstrate the insights into the mechanistic basis of thyroid hormone action that can arise from an ongoing commitment on the part of the research community to the deposition of discovery-scale datasets.

Association between Sudden Sensorineural Hearing Loss and Preexisting Thyroid Diseases: A Nationwide Case-Control Study in Taiwan

Background: Little evidence is available about the risk of sudden sensorineural hearing loss (SSNHL) in patients with thyroid diseases. We assessed whether a diagnosis of thyroid disease, particularly hyperthyroidism or hypothyroidism, is associated with SSNHL risk in an Asian population. Material and Methods: This case-control study was conducted with population-based data from Taiwan’s National Health Insurance Research Database from January 2000 to December 2013. The case group comprised 3331 adult patients with newly diagnosed SSNHL, and four controls without SSNHL for each case matched by sex, age, monthly income, and urbanization level of residence. Underlying Thyroid diseases were retrospectively evaluated in the case and control groups. Multivariate logistic regression analyses were used to explore relations between thyroid diseases and SSNHL. Results: Of the 3331 cases, 5.7% had preexisting thyroid diseases, whereas only 4.0% of the 13,324 controls had the same condition. After adjustment for sex, age, monthly income, urbanization level of residence, history of hypertension, diabetes mellitus, chronic otitis media, and hyperlipidemia, associations were identified between a history of either hypothyroidism (adjusted odds ratio [AOR], 1.54; 95% CI, 1.02–2.32; p = 0.042) or hyperthyroidism (AOR, 1.41; 95% CI, 1.07–1.85; p = 0.015) and an elevated risk of SSNHL. In subgroup analysis, the correlation between hypothyroidism and increased SSNHL risk remained significant only for patients aged over 50 years (AOR, 1.61; 95% CI, 1.01–2.57; p = 0.045), and that between hyperthyroidism and SSNHL was significant only for female patients (AOR, 1.48; 95% CI, 1.09–2.01; p = 0.012). Treatment for hypothyroidism and hyperthyroidism did not alter the association in subgroup analyses. Conclusion: Preexisting hypothyroidism and hyperthyroidism appear associated with SSNHL susceptibility in Taiwan. Physicians should be wary of this elevated risk of SSNHL among patients with previously diagnosed thyroid dysfunction, especially women and patients aged more than 50 years.

Preclinical studies on the toxicology, pharmacokinetics and safety of K1-70TM a human monoclonal autoantibody to the TSH receptor with TSH antagonist activity

Background

The human monoclonal autoantibody K1-70™ binds to the TSH receptor (TSHR) with high affinity and blocks TSHR cyclic AMP stimulation by TSH and thyroid stimulating autoantibodies.

Methods

The preclinical toxicology assessment following weekly intravenous (IV) or intramuscular (IM) administration of K1-70™ in rats and cynomolgus monkeys for 29 days was carried out. An assessment of delayed onset toxicity and/or reversibility of toxicity was made during a further 4 week treatment free period. The pharmacokinetic parameters of K1-70™ and the effects of different doses of K1-70™ on serum thyroid hormone levels in the study animals were determined in rats and primates after IV and IM administration.

Results

Low serum levels of T3 and T4 associated with markedly elevated levels of TSH were observed in the study animals following IV and IM administration of K1-70™. The toxicological findings were attributed to the pharmacology of K1-70™ and were consistent with the hypothyroid state. The no observable adverse effect level (NOAEL) could not be established in the rat study while in the primate study it was 100 mg/kg/dose for both males and females.

Conclusions

The toxicology, pharmacodynamic and pharmacokinetic data in this preclinical study were helpful in designing the first in human study with K1-70™ administered to subjects with Graves’ disease.

Normal-range thyroid-stimulating hormone levels and cardiovascular events and mortality in type 2 diabetes

AIMS

Thyroid dysfunction is a risk factor for cardiovascular disease. Whether thyroid function within the normal range is a risk factor for cardiovascular disease remains uncertain. The aim of this study is to evaluate whether plasma thyroid-stimulating hormone (TSH) levels in the normal range are a risk factor for cardiovascular disease and mortality in participants with type 2 diabetes mellitus with high cardiovascular risk.

METHODS

We included 1265 participants with high cardiovascular risk, type 2 diabetes, and TSH within the normal range (0.35-5.00 mIU/L) from the Second Manifestations of ARTerial disease cohort. The primary outcome was major cardiovascular events (MACE; vascular death, stroke and myocardial infarction). Secondary outcomes of interest were the separate vascular outcomes and all-cause mortality. Cox proportional hazard models were used to evaluate the risk of plasma TSH levels on all outcomes.

RESULTS

A total of 191 MACE occurred during a total follow-up of 8183 years. Plasma TSH levels were not associated with MACE (hazard ratio (HR) per mIU/L TSH increase 0.93; 95% confidence interval (95%CI) 0.80-1.08). With a total of 54 strokes during the study period, plasma TSH was associated with a lower risk of stroke (HR per mIU/L 0.64, 95% CI 0.45-0.89). There was no association between plasma TSH levels and risk of myocardial infarction, vascular death, or all-cause mortality.

CONCLUSIONS

Higher TSH levels within the normal range are associated with a lower risk of stroke in high-risk patients with type 2 diabetes, but not associated with the risk of other cardiovascular events or mortality.

Massive cerebral venous sinus thrombosis secondary to Graves' disease

Cerebral venous sinus thrombosis (CVT) is a rare cerebrovascular condition accounting for 0.5–1% of all types of strokes in the general population. Hyperthyroidism is associated with procoagulant and antifibrinolytic activity, thereby precipitating a hypercoagulable state that predisposes to CVT. We report the case of a 31-year-old Korean man with massive CVT and diagnosis of concomitant Graves’ disease at admission. Early diagnosis and prompt treatment of CVT are important to improve prognosis; therefore, CVT should be considered in the differential diagnosis in all patients with hyperthyroidism presenting with neurological symptoms.

Thyroid Function and Cardiovascular Disease: The Mediating Role of Coagulation Factors

CONTEXT

Mechanisms linking high and high-normal thyroid function to increased cardiovascular risk remain unclear. Hypothetically, coagulation can play a role.

OBJECTIVE

To investigate (i) the association of thyroid function with coagulation factors and (ii) whether coagulation factors mediate the association of thyroid function with cardiovascular disease (CVD).

DESIGN AND SETTING

Rotterdam Study, a population-based prospective study.

PARTICIPANTS AND MAIN OUTCOME MEASURES

In 5918 participants (mean age, 69.1 years), we measured TSH, free T4 (FT4), and coagulation factors [von Willebrand factor antigen (VWF:Ag), ADAMTS13 activity, fibrinogen]. Participants were followed up for the occurrence of cardiovascular events and deaths. Associations of thyroid function with coagulation factors (standardized z scores) and CVD were assessed through linear regression and Cox proportional hazards models, adjusted for potential confounders. We performed causal mediation analyses to evaluate whether the effect of thyroid function on CVD is mediated by coagulation.

RESULTS

Higher FT4 levels were associated with higher VWF:Ag (β = 0.34; 95% CI = 0.22, 0.47), lower ADAMTS13 activity (β = -0.22; 95%CI = -0.35, -0.09), and higher fibrinogen (β = 0.26; 95% CI = 0.13, 0.39); 857 incident cardiovascular events and 690 cardiovascular deaths occurred. FT4 levels were positively associated with cardiovascular events and deaths. The effect of FT4 on incident cardiovascular events was minimally mediated by fibrinogen (1.6%) but not by VWF:Ag and ADAMTS13. VWF:Ag and fibrinogen together mediated 10.0% of the effect of FT4 on cardiovascular deaths.

CONCLUSIONS

Higher FT4 levels were associated with higher VWF:Ag, lower ADAMTS13 activity, and higher fibrinogen levels, indicating a procoagulant state. VWF:Ag and fibrinogen explained up to 10% of the link between FT4 and CVD.

TUBB1 mutations cause thyroid dysgenesis associated with abnormal platelet physiology

The genetic causes of congenital hypothyroidism due to thyroid dysgenesis (TD) remain largely unknown. We identified three novel TUBB1 gene mutations that co‐segregated with TD in three distinct families leading to 1.1% of TUBB1 mutations in TD study cohort. TUBB1 (Tubulin, Beta 1 Class VI) encodes for a member of the β‐tubulin protein family. TUBB1 gene is expressed in the developing and adult thyroid in humans and mice. All three TUBB1 mutations lead to non‐functional α/β‐tubulin dimers that cannot be incorporated into microtubules. In mice, Tubb1 knock‐out disrupted microtubule integrity by preventing β1‐tubulin incorporation and impaired thyroid migration and thyroid hormone secretion. In addition, TUBB1 mutations caused the formation of macroplatelets and hyperaggregation of human platelets after stimulation by low doses of agonists. Our data highlight unexpected roles for β1‐tubulin in thyroid development and in platelet physiology. Finally, these findings expand the spectrum of the rare paediatric diseases related to mutations in tubulin‐coding genes and provide new insights into the genetic background and mechanisms involved in congenital hypothyroidism and thyroid dysgenesis.

An overview of the contribution of acupuncture to thyroid disorders

Thyroid dysfunction, affecting people of all ages, not only damages human growth and energy metabolism but is also comorbid with other illnesses such as cardiovascular disease, kidney disease and gastrointestinal disorders. With the increasing acceptance of alternative and complementary therapies, acupuncture, a traditional Chinese medical practice, has also been employed to address this problem. Analysing 29 clinical projects that were retrieved from 29 major digital databases and include 1757 patients aged 7-79 years from China, Italy, Korea, Macedonia and Russia, this narrative review offers an overview of the efficacy, and evaluated the safe and cost-effective use of acupuncture against hyperthyroidism, hypothyroidism and thyroid-relevant illnesses. Findings indicated reductions in patient symptoms and improvements in biomarkers where acupuncture was used alone or in combination therapy. In addition to showing the role of acupuncture as an alternative and complementary medicine or as an adjunctive therapy for curative and rehabilitative purposes, more well-designed researches are needed to achieve reliable data.

Comparison of Hospital Outcomes of Transcatheter AorticValve Implantation With Versus Without Hypothyroidism

Comparative outcomes of transcatheter aortic valve implantation (TAVI) in patients with and without hypothyroidism were not previously reported. This study aimed to appraise the clinical outcomes and impact of hypothyroidism on patients who underwent TAVI. Patients with hypothyroidism who underwent TAVI from 2011 to 2014 were identified in the National Inpatient Sample database using the International Classification of Diseases, ninth Revision, Clinical Modification. The primary outcome was the effect of hypothyroidism on inpatient mortality. Secondary outcomes were the impact of hypothyroidism on post-TAVI complications. We also evaluated the length of hospital stay and the cost of hospitalization. Propensity score-matched analysis was performed to address potential confounding. The hypothyroid patients who underwent TAVI had no significant increase in the risk of in-hospital mortality (odds ratio 0.78; 95% confidence interval 0.51 to 1.21, p = 0.282), or most postprocedural complications. However, hypothyroid patients were more likely to develop hemorrhage requiring transfusion (odds ratio 1.36, 95% confidence interval 1.05 to 1.76, p = 0.043). In conclusion, TAVI is a feasible and relatively safe alternative with reasonable in-hospital outcomes in patients with hypothyroidism and severe symptomatic aortic stenosis. However, hypothyroid patients are more likely to require a blood transfusion after TAVI. Additional randomized trials are needed to evaluate TAVR outcomes in hypothyroid patients.

Study on Coagulation Factor VIII and Fibrinogen Levels in Patients with Thyroid Disorders

INTRODUCTION

A kaleidoscope of coagulation disorders has been reported in patients with thyroid dysfunctions. Globally, these disorders involve both primary and secondary hemostasis and range from subclinical laboratory abnormalities to, more rarely, life-threatening hemorrhages or thrombotic events. While overt hypothyroidism appears to be associated with a bleeding tendency, hyperthyroidism emerged to have an increased risk of thrombotic events. As a controversy, subclinical hypothyroidism and mild hypothyroidism have been reported as prothrombotic state. The mechanisms involved in these observations are also not conformed.

OBJECTIVE

To study the levels of prothrombotic coagulation factor VIII and fibrinogen in patients with thyroid disorder at baseline and to correlate the change in these factors after attaining euthyroid state by treatment.

STUDY DESIGN

This was a longitudinal interventional study.

SUBJECTS AND METHODS

Forty patients were recruited based on the inclusion and exclusion criteria, and their coagulation profile (prothrombin time, aPTT, Factor VIII, and fibrinogen levels), routine hematological, and biochemical profile was done at baseline and 6 weeks after attaining euthyroid state.

RESULTS AND CONCLUSION

Hyperthyroidism and mild hypothyroidism were found to be hypercoagulable states and moderate-to-severe hypothyroidism as hypocoagulable states. Nevertheless, further observational and intervention studies are needed to provide more definitive information on the clinical relevance of this association, along with the potential implication for prevention and treatment of coagulation/fibrinolytic abnormalities in patients with thyroid dysfunction.

Cerebral venous sinus thrombosis precipitated by Graves' disease

Cerebral venous sinus thrombosis usually occurs in patients with a precipitating condition such as thrombophilic disorders, pregnancy or due to medications, such as oestrogens. Some case reports have reported the co-occurrence of cerebral venous sinus thrombosis in patients with hyperthyroidism. However, the association of cerebral venous sinus thrombosis with hyperthyroidism remains contentious. We present the case of a patient who presented with a clinical picture of cerebral venous sinus thrombosis with no obvious precipitating factor. Further investigations revealed the presence of hyperthyroidism due to Graves' disease, which was thought to be the provocative disorder for cerebral venous sinus thrombosis. We would like to draw the attention of clinicians to a possible causative association between cerebral venous sinus thrombosis and hyperthyroidism.

Maternal thyroid disorder in pregnancy and risk of cerebral palsy in the child: a population-based cohort study

Background

Cerebral palsy is the most frequent motor disability in childhood, but little is known about its etiology. It has been suggested that cerebral palsy risk may be increased by prenatal thyroid hormone disturbances. The objective of this study was to investigate whether maternal thyroid disorder is associated with increased risk of cerebral palsy.

Methods

A population-based cohort study using two study populations. 1) 1,270,079 children born in Denmark 1979–2007 identified in nationwide registers, and 2) 192,918 children born 1996–2009 recruited into the Danish National Birth Cohort and The Norwegian Mother and Child Cohort study, combined in the MOthers and BAbies in Norway and Denmark (MOBAND) collaboration cohort. Register-based and self-reported information on maternal thyroid disorder was studied in relation to risk of cerebral palsy and its unilateral and bilateral spastic subtypes using multiple logistic regression. Children were followed from the age of 1 year to the age of 6 years, and cerebral palsy was identified in nationwide registers with verified diagnoses.

Results

In register data, hypothyroidism was recognized in 12,929 (1.0%), hyperthyroidism in 9943 (0.8%), and unclassifiable thyroid disorder in 753 (< 0.1%) of the mothers. The odds ratio for an association between maternal thyroid disorder and bilateral spastic cerebral palsy was 1.0 (95% CI: 0.7–1.5). Maternal thyroid disorder identified during pregnancy was associated with elevated risk of unilateral spastic cerebral palsy (odds ratio 3.1 (95% CI: 1.2–8.4)). In MOBAND, 3042 (1.6%) of the mothers reported a thyroid disorder in pregnancy, which was not associated with cerebral palsy overall (odds ratio 1.2 (95% CI: 0.6–2.4)).

Conclusions

Maternal thyroid disorder overall was not related to bilateral spastic cerebral palsy, but maternal thyroid disorder identified in pregnancy was associated with increased risk of unilateral spastic cerebral palsy. These findings should be replicated in studies making use of maternal blood samples.

Electronic supplementary material

The online version of this article (10.1186/s12887-018-1152-5) contains supplementary material, which is available to authorized users.

Hypothyroidism and hyperthyroidism change ectoenzyme activity in rat platelets

The purinergic system has an important role in the regulation of vascular functions. The interference of thyroid hormones in this system and in cardiovascular events has been studied in recent years. However, the mechanisms involved in vascular, purinergic, and oxidative changes in thyroid disorders are not completely understood. Therefore, the present study aimed to assess purinergic enzyme activity in platelets from rats with hypothyroidism and hyperthyroidism induced, respectively, by continuous exposure to methimazole (MMI) at 20 mg/100 mL or L-thyroxine at 1.2 mg/100 mL in drinking water for 1 month. Results showed that rats exposed to L-thyroxine had a significant decrease in NTPDase activity, wherein ATP hydrolysis was 53% lower and ADP hydrolysis was 40% lower. Moreover, ecto-5'-nucleotidase activity was decreased in both groups, by 39% in the hypothyroidism group and by 52% in the hyperthyroidism group. On the other hand, adenosine deaminase (ADA) activity was increased in hyperthyroidism (75%), and nucleotide pyrophosphatase/phosphodiesterase (NPP) activity was increased in animals with hypothyroidism (127%) and those with hyperthyroidism (128%). Our findings suggest that changes in purinergic enzyme and purine levels could contribute to the undesirable effects of thyroid disturbances. Moreover, oxidative stress and, in particular, a high level of ROS production, showed a causal relation with changes in ectonucleotidase activity and nucleotide and nucleoside levels.

Thyroid function and atrial fibrillation: Is there a mediating role for epicardial adipose tissue?

Background

The underlying mechanism of the association between thyroid function and atrial fibrillation (AF) is poorly understood, but epicardial adipose tissue (EAT) could be a promising mediator.

Methods

In the 1995 participants (mean age 64.5 years) from the population-based Rotterdam Study, we measured thyroid function (thyroid-stimulating hormone, free thyroxine [FT4]) and performed computed tomography to quantify EAT volumes. All participants were followed for the occurrence of AF. We assessed associations of thyroid-stimulating hormone and FT4 with EAT and AF and performed causal mediation analysis to decompose the overall effect of thyroid function on AF with EAT as mediator.

Results

Higher FT4 levels were associated with larger EAT volumes in persons with large waist circumferences, defined by sex-specific cutoffs (0.08 mL more EAT per 1-SD increase in FT4, 95% CI: 0.02, 0.14), but not in persons with a normal waist circumference. In persons with a large waist circumference, higher FT4 levels were associated with a higher AF risk (hazard ratio 1.50, 95% CI: 1.22, 1.83). We found no evidence of a mediating role of EAT in the association of thyroid function with AF (mediated interaction 1.6%, pure indirect effect 3.2%). The estimate of reference interaction of EAT with thyroid function on AF risk was more substantial (10.8%), but statistically nonsignificant.

Conclusions

Higher FT4 levels are associated with larger EAT volumes in persons with abdominal obesity. We report no mediating role of EAT in the association of thyroid function with AF, but found evidence for a suggested interaction of FT4 with EAT volumes on AF risk.

Thromboelastography in wild Florida manatees (Trichechus manatus latirostris)

BACKGROUND

Thromboelastography (TEG) provides a comprehensive evaluation of blood clot formation. This test can be used to identify abnormalities in coagulation by assessing multiple aspects of the clotting cascade, including the speed of clot initiation and formation, clot strength, and ultimately fibrinolysis. Thromboembolic disease has been hypothesized to play a role in the pathophysiology of cold stress syndrome (CSS), an important cause of mortality in the threatened Florida manatee (Trichechus manatus latirostris).

OBJECTIVES

The objective of this study was to establish thromboelastography RIs using the TEG 5000 with citrated whole blood samples and kaolin activation in wild, healthy manatees.

METHODS

In December 2014 and January 2015, 29 wild manatees (17 male and 12 female) were blood sampled as part of the annual wild manatee health assessments organized by United States Geological Survey (USGS). TEG was performed using citrated kaolin-activated samples.

RESULTS

The samples were obtained from manatees caught in Crystal River, Citrus County, and used to identify the mean ± SD of normal TEG parameters: R = reaction time 2.1 minutes (0.8), K = clot formation time 0.8 min (0), α angle = 83.1° (2), MA = maximum amplitude 75 mm (7.6), and LY30 = clot lysis 0.41% (0.68). No significant differences were found between manatee size, sex, or time between sampling and running the test.

CONCLUSIONS

Manatee TEG parameters demonstrate a relatively hypercoagulable condition when compared to other mammals. This information will facilitate detection of changes in hemostasis during injury and disease and provide a valuable reference range.