Clinical course of autoimmune thyroid diseases in women with prolactinomas: Results from a prospective study in a single tertiary centre

INTRODUCTION

Several retrospective and cross-sectional studies have revealed a higher prevalence of autoimmune thyroid diseases (AITD) with a predominance of autoimmune hypothyroidism in prolactinoma patients compared to the general population. To date, we have no data on the clinical course of AITD in these patients. The aim of this prospective study was to assess the clinical course of AITD in female patients with prolactinomas compared to an age- and thyroid-risk factors-matched control group.

MATERIALS AND METHODS

The study population consisted of 144 females (71 patients/73 controls) who underwent approximately a 6-year follow-up. Physical examination, thyroid ultrasound and laboratory testing (measurement of antibodies to thyroglobulin, thyroid peroxidase, TSH-receptor; serum TSH and FT4 levels) were performed twice - at the baseline and at the follow-up visits.

RESULTS

AITD were diagnosed in 26.8% (n=19) of the patients and 9.6% (n=7) of the controls (p=0.007) at baseline visit. At the end of the follow-up (FU), these percentages increased to 33.8% (n=24) among the patients versus 12.3% (n=9) in the control group (p=0.002). Hypothyroidism was significantly more frequent in prolactinoma patients than in controls at the end of the study (19.7% vs. 4.1%; p=0.003). Two prolactinoma patients had hyperthyroidism at the baseline visit and restored euthyroid state with negative TSH-receptor antibodies during the follow-up. We did not observe hyperthyroidism in the control group. Among the hypothyroid subsets, the average daily levothyroxine dose at FU visit varied from 25 to 200mcg in the prolactinoma group compared to 25 to 50mcg in the control group.

CONCLUSIONS

Female patients with prolactinomas seem to be prone to autoimmune hypothyroidism. As a pathogenetic mechanism, we could suggest the selective immunomodulatory action of PRL predominantly on cell autoimmunity, complement activation and antibody-dependent cytotoxicity, resulting in earlier and more rapid progression of Hashimoto's thyroiditis towards hypothyroid state in genetically predisposed individuals.

Hyperthyroidism and cardiovascular risk factors: A nationwide study

BACKGROUND

Thyroid hormones (THs) have important effects on cardiovascular (CV) physiology. Thyroid disorders are accompanied by serious effects on the CV system.

OBJECTIVE

To study the association between hyperthyroidism and the main CV risk factors (CVRFs), such as hypertension, dyslipidemia, diabetes and smoking in the Spanish population.

MATERIAL AND METHODS

An observational, retrospective, non-interventional study was performed using the statistical portal of the Spanish Ministry of Health associated with the Base de Datos Clínicos de Atención Primaria (BDCA) database.

RESULTS

In 2019, 384,182 people [300,243 women (78.1%)] were diagnosed with hyperthyroidism, which represents 1.0% of the population with health problems registered in the BDCAP database (38,365,258 people). The prevalence of hyperthyroidism was more frequent in women (2.48 times) than in men and increased with age. When the whole population was considered, the prevalence of hypertension (34.90% vs. 19.90%; odds ratio, OR 2.16, 95% CI 2.14-2.17), dyslipidemia (34.47% vs. 21.57%; OR 1.90, 95% CI 1.88-1.91), diabetes (12.88% vs. 8.12%; OR 1.66, 95% CI 1.65-1.68) and smoking (10.89% vs. 7.61%; OR 1.48, 95% CI 1.46-1.49) was significantly (p<0.0001) higher in the population diagnosed with hyperthyroidism compared to those without this diagnosis. These significant differences were maintained in both women and men. A separate analysis of the age group 65 years or older showed statistically significant (p<0.0001) differences in the prevalence of hypertension (66.26% vs. 59.43%; OR 1.34, 95% CI 1.33-1.36), dyslipidemia (52.61% vs. 49.05%; OR 1.15, 95% CI 1.14-1.17) and smoking (6.29% vs. 5.93%; OR 1.06, 95% CI 1.04-1.09) between patients with and without a diagnosis of hyperthyroidism, but not in the prevalence of diabetes, which was similar (24.63% vs. 24.63%; OR 1.00, 95% CI 0.99-1.01; p=0.89).

CONCLUSION

Our study shows that the diagnosis of hyperthyroidism is significantly associated with the main CVRFs in Spanish population attended by primary care regardless of the gender of the patients. This association disappears in those patients aged 65 years or older diagnosed with diabetes.

Thyroid disorders associated with immune control point inhibitors

INTRODUCTION

Immune checkpoint inhibitors (ICPI) have improved progression-free survival in several solid tumors. Side effects are related to overstimulation of the immune system. Thyroid dysfunction (TD) is the most common endocrine immune-related adverse event of ICPI.

OBJECTIVE

To describe the clinical presentation and the course of TD in cancer patients treated with ICPI referred to an endocrinology outpatient clinic.

MATERIAL AND METHODS

This was a descriptive, retrospective and multicenter study of patients with TD associated with ICPI in six Spanish hospitals.

RESULTS

120 patients (50.8% women), mean age 60 ± 12 years were included. The initial TD was hypothyroidism in 49% of patients and hyperthyroidism in 51%, with an average of 76 (41-140) and 43 (26-82) days respectively between the onset of ICPI and the analytical alteration. Significantly, the earlier the first analytical determination was, the greater the prevalence of hyperthyroidism. A turnover was observed in 80% of subjects during follow-up, mostly from hyperthyroidism to hypothyroidism. Twenty-one percent received double ICPI therapy. The most frequent form of presentation in monotherapy was hypothyroidism (57%), and in double therapy it was hyperthyroidism (77%) (p = 0.002). Patients under double therapy showed thyroid alterations earlier than those in the monotherapy group (p = 0.001). After a follow-up of 205 (112-360) days, half of the patients continued under levothyroxine treatment.

CONCLUSIONS

Hypothyroidism and hyperthyroidism present in a similar proportion in cancer patients undergoing ICPI therapy. Our results suggest that transitory hyperthyroidism may not be detected in a relevant number of cases. In addition, TD in double therapy presents earlier. This should be taken into account in the follow-up protocols of these patients.

Follow-up of infants born to mothers with Graves' disease

INTRODUCTION

The prevalence of neonatal hyperthyroidism (HN) due to maternal Graves Disease (GD) ranges from 0.1 to 2.7%. It may occur in pregnant women with the following: active DG, after treatment with radioactive iodine, anti-thyroid or thyroidectomy or with a previous child with hyperthyroidism. The aim of our observational study was to evaluate the follow-up of infants born to mothers with GD at a Tertiary Hospital prior to the implementation of a follow-up protocol.

METHODS

This was a retrospective observational study using data from the medical records of mothers with a diagnosis of GD and their newborns from January 2013 until May 2018. Newborns were divided into two groups: high and low risk for NH according to maternal TRAb, third trimester treatment and signs of fetal hyperthyroidism.

RESULTS

We identified 31 newborns, 58% female; 87% high risk. In none of the newborns was umbilical cord blood collected. In the high risk group, 22% had thyroid function evaluation at day-1, one patient presented with hyperthyroidism and 82% were asymptomatic. Considering the cases with an insufficient blood sample for analysis, 9 consultations would have been spared. We found a significant delay in obtaining the high-risk group results which would have spared 10 appointments. A positive correlation was found between age at outpatient clinic discharge and the number of appointments and the maternal TRAb titer.

CONCLUSION

The correct surveillance of pregnancy and newborns with identification of those at high risk is essential to avoid unnecessary consultations and blood analyses that increase parental anxiety and hospital costs. Consequently, a multidisciplinary protocol was created to standardize the approach.

Follow-up of infants born to mothers with Graves' disease

INTRODUCTION

The prevalence of neonatal hyperthyroidism (HN) due to maternal Graves Disease (GD) ranges from 0.1 to 2.7%. It may occur in pregnant women with the following: active DG, after treatment with radioactive iodine, anti-thyroid or thyroidectomy or with a previous child with hyperthyroidism. The aim of our observational study was to evaluate the follow-up of infants born to mothers with GD at a Tertiary Hospital prior to the implementation of a follow-up protocol.

METHODS

This was a retrospective observational study using data from the medical records of mothers with a diagnosis of GD and their newborns from January 2013 until May 2018. Newborns were divided into two groups: high and low risk for NH according to maternal TRAb, third trimester treatment and signs of fetal hyperthyroidism.

RESULTS

We identified 31 newborns, 58% female; 87% high risk. In none of the newborns was umbilical cord blood collected. In the high risk group, 22% had thyroid function evaluation at day-1, one patient presented with hyperthyroidism and 82% were asymptomatic. Considering the cases with an insufficient blood sample for analysis, 9 consultations would have been spared. We found a significant delay in obtaining the high-risk group results which would have spared 10 appointments. A positive correlation was found between age at outpatient clinic discharge and the number of appointments and the maternal TRAb titer.

CONCLUSION

The correct surveillance of pregnancy and newborns with identification of those at high risk is essential to avoid unnecessary consultations and blood analyses that increase parental anxiety and hospital costs. Consequently, a multidisciplinary protocol was created to standardize the approach.

The relationship between history of thyroid diseases and risk of in-hospital cardiovascular outcomes in patients with atrial fibrillation: Findings From the CCC-AF (Improving Care for Cardiovascular Disease in China-Atrial Fibrillation) Project

BACKGROUND

Atrial fibrillation (AF) has the close relation to thyroid dysfunction and these two diseases lead to poor cardiovascular outcomes. But the prognostic value of thyroid diseases in AF remains unclear. We aimed to determine whether history of thyroid diseases is associated with risk of in-hospital cardiovascular outcomes in AF.

METHODS

Based on the data from the CCC-AF (Improving Care for Cardiovascular Diseases in China-Atrial Fibrillation) project, 31,486 inpatients with a definitive diagnosis of AF and record of history of thyroid diseases were included. Logistic regression analysis was performed to investigate the relationship between history of thyroid diseases and risk of in-hospital major adverse cardiovascular events (MACE) in AF.

RESULTS

Among AF patients, 503 (1.6%) had a history of hypothyroidism, 642 (2.0%) had a history of hyperthyroidism and 30,341 (96.4%) had no thyroid dysfunction. During this hospitalization, 5146 (16.3%) AF patients suffered from MACE. The incidence was 13.1% in hypothyroidism, 16.3% in euthyroidism and 19.0% in hyperthyroidism, in which there was a significant difference among three groups (p=0.028). Multivariable logistic regression analysis revealed that history of hypothyroidism decreased but history of hyperthyroidism increased the risk of in-hospital MACE in AF patients (adjusted odds ratio [OR]=0.603; 95% confidence interval [CI], 0.449-0.811; p=0.001 versus adjusted OR=1.327; 95% CI, 1.060-1.661; p=0.013).

CONCLUSION

History of hypothyroidism was an independent protective factor, whereas history of hyperthyroidism was an independent risk factor for in-hospital cardiovascular outcomes in AF. Our study indicated that hyperthyroidism should be treated aggressively in order to improve the prognosis of AF.

Thyroid orbitopathy masked a carotid-cavernous fistula. Case report

The case concerns a 73 year-old female with a diagnosis of hyperthyroidism of 8 months onset. Since then, she has suffered hyperaemia and ocular proptosis. Bilateral exophthalmos was observed in the physical examination, along with mild conjunctival hyperaemia in the right eye associated with dilated episcleral vessels. Computed tomography showed enlarged inferior rectus with no signs of ocular nerve or ophthalmic superior vein compression. In the orbital Doppler ultrasound scan, there was an arterialised flow over the superior ophthalmic vein, giving a possible diagnosis of cavernous carotid. Thyroid orbitopathy with a cavernous carotid fistula is an unusual combination in which the clinical signs of both pathologies can mask the complete diagnosis; thus it is important to be acquainted with both pathologies for their correct management and multidisciplinary treatment.

Nivolumab-induced thyroid dysfunction in patients with lung cancer

BACKGROUND

Nivolumab is an anti-cancer monoclonal antibody that inhibits PD1 and modulates T-cell response. It has been shown to significantly improve survival in several types of cancer, but clinical trials have also reported an increased risk of developing immune-related adverse events (IRAEs). Endocrine IRAEs may be particularly relevant.

OBJECTIVE

To comprehensively evaluate the clinical presentation of endocrine IRAEs in patients with lung cancer treated with nivolumab. Potential risk factors are analyzed, and strategies for IRAE management are proposed.

METHODS

Forty consecutive patients treated with nivolumab for advanced non-small cell lung cancer (NSCLC) were studied, paying particular attention to development of endocrine IRAEs (thyroid, hypophyseal, adrenal, or pancreatic) and clinical outcome.

RESULTS

Thyroid function changes were found in 9 patients (22.5%), of which six developed hypothyroidism and three had hyperthyroidism after a median of 3.8 and 2.3 cycles of nivolumab respectively. Only one patient had thyroid-related symptoms. Thyroid autoimmunity was negative in all cases. Hyperthyroid patients showed no uptake in iodine scintigraphy, and their hormone values returned to normal in less than six months. Nivolumab was discontinued for toxicity in one patient. One patient with hyperthyroidism also developed autoimmune diabetes, and one patient with hypothyroidism also had hypogonadism. After a median follow-up of 7.6 months, 25 patients (62.5%) showed response to nivolumab. Univariate and multivariate analyses showed no differences between patients who developed thyroid changes and those who did not.

CONCLUSIONS

Thyroid changes after treatment with nivolumab are common and warrant active laboratory monitoring. The underlying mechanisms and their relevance deserve further research.

Treatment of Graves' disease in children: The Portuguese experience

INTRODUCTION

Graves' disease (GD) is an autoimmune thyroid disease, common in adults but rare in children. The best therapeutic approach remains controversial.

OBJECTIVES

To ascertain the current treatment of pediatric GD in Portugal and to assess the clinical and biochemical factors that determine definitive/long-term remission after treatment with antithyroid drugs (ATDs).

PATIENTS AND METHODS

A retrospective analysis of data about pediatric GD treatment collected from a nationwide survey conducted by the Portuguese Society of Pediatric Endocrinology and Diabetology from May to August 2013. Population was categorized based on sex, age, use of ATDs, dosage, treatment duration, adverse reactions, thyrotropin receptor-stimulating antibody (TRAB) titer, remission and remission/relapse rates, and definitive treatment, and divided into group A (with ongoing treatment) and group B (with treatment stopped). Group B was subdivided into 'Remission', 'Remission+relapse' and 'No remission' subgroups based on the course of disease. The same parameters were compared between both groups.

RESULTS

Survey response rate was 77%; 152 subjects, 116 female, mean age at diagnosis 11.23±3.46 years. They all started treatment with ATDs, 70.4% with thiamazole, with a mean treatment duration of 32.38±28.29 months, and 5.9% had adverse effects. Remission rate was 32.6%. Lower age at diagnosis correlated with higher remission rates. Treatment duration was longer when propylthiouracil was used. Initial TRAB titer was significantly higher in the 'No remission' group. Surgery and radioiodine were used as second-line treatments.

CONCLUSION

Our study results were similar to those reported in the literature. Age and TRAB titer were identified as potential clinical and laboratory determinants of remission. Based on risk/benefit analysis, it was concluded that treatment should be individualized based on age, accessibility to treatments, and physician's experience.

Study of factors that influence the outcome of 131I treatment in hyperthyroidism secondary to nodular goitre

OBJECTIVE

To assess the outcome after ¹³¹I treatment in patients with multinodular (MNG) and nodular toxic goitre (NTG) according to the administered dose and other factors related to the patient, pathology, or previous treatments.

MATERIAL AND METHODS

A retrospective study was conducted on 108 patients (67 MNG and 41 NTG) treated in our department, with a follow-up period of at least 2 years. Development of hypothyroidism and treatment failure were evaluated along with their relationship with the administered dose and other factors such as age, sex, grade of hyperthyroidism, type of goitre, presence of autoimmunity, or previous antithyroid medication.

RESULTS

More than one-third (36.9%) of MNG patients, and even higher proportion of NTG patients (51.2%) developed non-transient hypothyroidism, particularly in those receiving 740MBq (66.7%). No relationship was found with any other variable. The development of early hypothyroidism (before one year) was also not related to any variable. Treatment failure was not related to the dose, but in MNG there was a relationship with male gender, presence of autoimmunity, or previous antithyroid drugs use.

CONCLUSIONS

The high rate of hypothyroidism obtained with high doses of ¹³¹I in hyperthyroidism secondary to nodular goitre treatment suggests that lower doses might be sufficient to control the disease without an increase in treatment failures. Only patients with positive autoimmunity, in previous anti-thyroid medication, and perhaps male gender in MNG might be given higher doses, as the failure rate increases, but further studies are required.

Recombinant human thyrotropin stimulation prior to 131I therapy in toxic multinodular goitre with low radioactive iodine uptake

AIM

Stimulation with recombinant human thyrotropin (rhTSH) increases thyroid radioiodine uptake, and is an aid to ¹³¹I therapy in non-toxic multinodular goitre (MNG). However, there are not many studies using rhTSH prior to ¹³¹I in toxic multinodular goitre to improve hyperthyroidism and compressive symptoms.

MATERIAL AND METHOD

A prospective study was conducted on patients with MNG and hyperthyroidism. Patients were recruited consecutively and divided into group I, stimulated with 0.3mg of rhTSH before radioiodine therapy, and a control group or group II, without stimulation. Thyroid function, radioiodine thyroid uptake, thyroid weight, and compressive symptoms were measured, and patients were followed-up for 9 months.

RESULTS

Group I consisted of 16 patients (14 women), with a mean age 69.7 years, and group II with 16 patients (12 women), with a mean age 70.7 years. After stimulation with 0.3mg rhTSH in group I, ¹³¹I uptake (RAIU) at 24h increased by 78.4%, and the estimated absorbed dose by 89.3%. In group II, the estimated absorbed dose was lower than group I after stimulation with rhTSH (29.8Gy vs. 56.4Gy; P=0.001). At 9 months of follow-up, hyperthyroidism was controlled in 87.5% of patients in group I, and 56.2% in group II (P=0.049). The mean reduction in thyroid weight was higher in group I than in group II (39.3% vs. 26.9%; P=0.017), with a tendency towards subjective improvement of compressive symptoms in group I, although non-significant. Only 2 patients described tachycardias after rhTSH administration, which were resolved with beta-blockers.

CONCLUSION

Stimulation with 0.3mg of recombinant human thyrotropin prior to radioiodine therapy achieves a reduction in thyroid weight and functional improvement in patients with hyperthyroidism and multinodular goitre with low uptake, and with no need for hospital admission.

Thyroid dysfunction in the era of precision medicine

The launching of the Precision Medicine Initiative by the President of the United States in January 2015 was an invitation for all healthcare professionals to review their practice. This call should stimulate thyroidologists working in different areas (from basic research or epidemiology to the frontline of the clinical arena or to those designing public health programs) to be aware of this new outlook. The aim of the initiative is to eradicate imprecision in estimating the probability of a correct diagnosis, to be as sure as possible of the most effective treatment, and to maximize the chances of a successful outcome. This paper summarizes some of the current challenges faced by endocrinologists in the field of thyroid dysfunction, and illustrates how precision medicine may improve diagnosis and therapy in the future.

[Thyroid dysfunction in pregnancy. Consensus document. Andalusian Society of Endocrinology and Nutrition (SAEN)]

A position statement on the diagnosis and treatment of thyroid dysfunction in pregnancy has been agreed on behalf of The Sociedad Andaluza de Endocrinología y Nutrición (SAEN), based on a review of the literature to date and all good clinical practice guidelines. The document is set out in different sections as regards the diagnosis and treatment of, overt and subclinical hypo- and hyperthyroidism, isolated hypothyroxinaemia and postpartum thyroiditis. It also justifies the implementation of universal screening for thyroid dysfunction in pregnancy, and provides practitioners who care for these patients with tool for rational decision making.

[Thyroid dysfunction during pregnancy]

Recent clinical practice guidelines on thyroid dysfunction and pregnancy have changed health care provided to pregnant women, although their recommendations are under constant revision. Trimester- and area-specific reference ranges for serum thyroid-stimulating hormone are required for proper diagnosis of hypothyroidism and hyperthyroidism. There is no doubt on the need of therapy for overt hypothyroidism, while therapy for subclinical hypothyroidism is controversial. Further research is needed to settle adverse effects of isolated hypothyroxinemia and thyroid autoimmunity. Differentiation between hyperthyroidism due to Graves' disease and the usually self-limited gestational transient thyrotoxicosis is critical. It is also important to recognize risk factors for postpartum thyroiditis. Supplementation with iodine is recommended to maintain adequate iodine nutrition during pregnancy and avoid serious consequences in offspring. Controversy remains about universal screening for thyroid disease during pregnancy or case-finding in high-risk women. Opinions of some scientific societies and recent cost-benefit studies favour universal screening. Randomized controlled studies currently under development should reduce the uncertainties that still remain in this area.

Effects of thyroid hormones on the heart

Thyroid hormones have a significant impact on heart function, mediated by genomic and non-genomic effects. Consequently, thyroid hormone deficiencies, as well as excesses, are expected to result in profound changes in cardiac function regulation and cardiovascular hemodynamics. Thyroid hormones upregulate the expression of the sarcoplasmic reticulum calcium-activated ATPase and downregulate the expression of phospholamban. Overall, hyperthyroidism is characterized by an increase in resting heart rate, blood volume, stroke volume, myocardial contractility, and ejection fraction. The development of "high-output heart failure" in hyperthyroidism may be due to "tachycardia-mediated cardiomyopathy". On the other hand, in a hypothyroid state, thyroid hormone deficiency results in lower heart rate and weakening of myocardial contraction and relaxation, with prolonged systolic and early diastolic times. Cardiac preload is decreased due to impaired diastolic function. Cardiac afterload is increased, and chronotropic and inotropic functions are reduced. Subclinical thyroid dysfunction is relatively common in patients over 65 years of age. In general, subclinical hypothyroidism increases the risk of coronary heart disease (CHD) mortality and CHD events, but not of total mortality. The risk of CHD mortality and atrial fibrillation (but not other outcomes) in subclinical hyperthyroidism is higher among patients with very low levels of thyrotropin. Finally, medications such as amiodarone may induce hypothyroidism (mediated by the Wolff-Chaikoff), as well as hyperthyroidism (mediated by the Jod-Basedow effect). In both instances, the underlying cause is the high concentration of iodine in this medication.