Decision Making in Subclinical Thyroid Disease

Reasons for Referring Patients for Determining the Hormonal Status of the Thyroid Gland From the Level of Primary Health Care in Sarajevo Canton

Background

Thyroid dysfunction includes hyper- and hypofunction of the thyroid gland (hyperthyroidism and hypothyroidism). The spectrum encompasses both subclinical and clinical disease presentation. The etiology is vast and varied, as are the risk factors and simptoms.

Objective

The main aim of the research is to indicate the leading symptom for initial thyroid hormone status evaluation, as well as to identify the distribution of positive and negative test results, and specific disorders according to sex and age groups.

Methods

The research is designed as a retrospective, clinical, descriptive study. There were 500 participants included, 355 female and 145 male. Patients were referred to the Department of endocrinology by their primary care physicians. The data was collected through patient documentation.

Results

The study included 500 participants, 71% of diagnostic requests made were for women. 80% of subjects had normal thyroid hormone status, p<0.001. Most requests were made for the 41-60 age group, p<0.001. Women had similar number of positive and negative test outcomes, as well as men. When it comes to the age groups, outcomes were similar in all of them, 15-23% positive and 77-85% negative. There were significant differences in the type of symptom expressed in both men and women, as well as all the age groups. Men reported high blood pressure as the most common symptom (30.3%), while women reported weight gain (22.3%). In the 18-25 and 26-40 age groups most common symptom belongs to the category of other. Age group of 41-60 reported weight gain as the most common symptom, while in participants older than 60, high blood pressure is proven to be the most common. Hypothyroidism is the most common disorder in both men and women, as well as in all age groups.

Conclusion

It is statistically proven that there were more requests made for women, and older age groups. Leading symptom for initial thyroid hormone status evaluation is high blood pressure. There is no statistically significant difference in distribution of thyroid disorders according to sex or age groups.

Cardiovascular outcomes in subclinical thyroid disease: an update

PURPOSE OF REVIEW

Subclinical thyroid disease is defined by a thyroid stimulating hormone (TSH) level outside of the normal range with normal circulating thyroid hormone levels. Excess adverse cardiovascular outcomes have been observed in certain patient populations with subclinical hypothyroidism (SCH) and hyperthyroidism (SCHr). The role of thyroid hormone and antithyroid treatments for subclinical thyroid disease remains debated.

RECENT FINDINGS

Cardiovascular disease appears to be a major mediator of all-cause mortality in patients with SCH, in particular those aged at least 60 years of age. In contrast, pooled clinical trial results did not find that levothyroxine reduced the incidence of cardiovascular events or mortality in this patient population. The association between SCHr and atrial fibrillation is well established; however, a 5-year follow-up of older patients with mild (TSH 0.1-0.4 mIU/l) SCHr found no increased incidence of atrial fibrillation. Separately, SCHr was associated with derangements in endothelial progenitor cell function that may underlie vascular disease independent from effects on cardiac function.

SUMMARY

The impact of treatment of subclinical thyroid disease on cardiovascular outcomes remains uncertain. Additional prospective and trial data are needed to evaluate treatment effects on cardiovascular outcomes in younger populations.

Electrochemical immunoassay for one-pot detection of thyroxin (T4) and thyroid-stimulating hormone (TSH) using magnetic and Janus nanoparticles

Concurrent measurement of thyroid-stimulating hormone (TSH) and thyroxine (T4) hormones profoundly help clinicians diagnose hyper- and hypothyroidism. This work demonstrates the development of a sandwich-type electrochemical immunoassay using Janus and magnetic nanoparticles for one-pot detection of thyroxine (T4) and thyroid-stimulating hormone (TSH). The signaling probe was developed by preparing Janus cadmium (CdO) and zinc oxide (ZnO) NPs decorated by T4/TSH-specific molecularly imprinted polymers (MIP_T4-CdO and MIP_TSH-ZnO). The capture probe was obtained by coating magnetic Fe₃O₄ NPs with 1,3-Bis(3-carboxy propyl) tetramethyl disiloxane and activating using N-hydroxy succinimide (NHS) and 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC), and finally conjugating with T4/TSH-specific antibodies. To analyze T4 and TSH in actual samples, MIP_T4-CdO and MIP_TSH-ZnO were added to the sample solutions, and after incubation, capture probes (Fe₃O₄-Ab_TSH and Fe₃O₄-Ab_T4) were added. An external magnetic field was used to separate the sandwiched nanosystem, followed by adding a dilute solution of nitric acid (HNO₃) to dissolve CdO and ZnO NPs and free Cd(II) and Zn(II) cations. The concentration of these cations was determined using constant-current potentiometric stripping analysis (cc-PSA) on screen-printed electrodes (SPE) modified with multi-walled carbon nanotubes (MWCNT). The obtained signals for Cd(II) and Zn(II) were proportional to T4 and TSH concentrations. Limits of detection (LOD) for T4 and TSH analyses were respectively 0.02 ng.dL^-1 and 0.0002 µU.mL^-1 with a linear range of 0.05-50 ng.dL^-1 and 0.001-100 µU.mL^-1. The proposed nanosystem's main advantage is the simultaneous detection of T4 and TSH in clinical samples with high sensitivity, selectivity, and stability.

Serum Lipidomic Analysis Reveals Biomarkers and Metabolic Pathways of Thyroid Dysfunction

Abnormal thyroid hormone secretion is the most important feature of hypothyroidism and plays an important role in lipid metabolism. However, their connection has not been clearly established. This study aimed to identify the serum biomarkers and metabolic pathways associated with hyperthyroidism and hypothyroidism. The study enrolled discovery and validation sets of 175 and 300 participants, respectively, to identify and validate the serum biomarkers of hyperthyroidism and hypothyroidism via ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry lipidomics through univariate and multivariate analyses. Eight and six biomarkers were identified for hyperthyroidism and hypothyroidism, respectively. Spearman correlation analysis was used to assess the correlation between the biomarkers and thyroid dysfunction indicators; subsequently, metabolic pathway and network analyses were performed for these biomarkers. Most biomarkers exhibited significant correlation with thyroid dysfunction indicators, mainly being enriched in the glycerophospholipid (GPL) metabolism. The diagnostic accuracies of the biomarkers and biomarker panels were assessed via receiver operating characteristic curve analysis. All the biomarkers demonstrated good diagnostic performance, and the hyperthyroidism and hypothyroidism biomarker panels reached an area under the curve value of 1.000. The results were validated using the validation set. Therefore, our findings revealed that thyroid dysfunction primarily affects the human metabolism via the GPL metabolism, thus providing a theoretical basis for the clinical prevention and control of thyroid dysfunction.

Preliminary observation of thyroid function changes in subclinical thyroid diseases

BACKGROUND

It is estimated that 1.95% and 5.55% of adults in China suffer from subclinical thyroid diseases, which is difficult to diagnose and treat.

OBJECTIVE

This study aimed to explore the development and prognosis of subclinical thyroid diseases to provide a reference from our single center experience.

METHODS

A total of 240 cases from April 2019 to August 2021 in the laboratory information system database of Huanghua Development Boai Hospital were retrospectively analyzed. Binary logistic regression was conducted to analyze odds ratio (OR) of subclinical thyroid disease types returning to a normal state.

RESULTS

Among the patients hypothyroidism Ia and hyperthyroidism Ia were the most common type with conversion to the normal state (P< 0.001). TSH level of patients with conversion to a normal state was significantly lower than that of those who developed to abnormal disease (P= 0.015). The OR values of hyperthyroidism Ia and hypothyroidism Ia that returned to a normal state compared with hyperthyroidism Ib were 2.659 (1.159 ∼ 6.096, P= 0.021) and 3.138 (1.1.278 ∼ 7.709, P= 0.013), respectively. The OR value of hypothyroidism Ib that returned to normal compared with hyperthyroidism Ib was 0.629 (0.131 ∼ 3.010, P= 0.561). Thyroid hormone levels, age, and gender at first diagnosis were not impact factor for prognosis of subclincal thyroid disease (P> 0.05).

CONCLUSION

Cases with grade hypothyroidism Ia and hyperthyroidism Ia are more likely to revert to normal state than other subclinical thyroid diseases. TSH reference range should be explored for diagnosis and treatment.

Ameliorative Effect of Ethanolic Echinacea purpurea against Hyperthyroidism-Induced Oxidative Stress via AMRK and PPAR Signal Pathway Using Transcriptomics and Network Pharmacology Analysis

Echinacea purpurea (L.) Moench (EP) is a well-known botanical supplement with antioxidant characteristics. However, the effects of EP on oxidative stress induced by hyperthyroidism have not yet been studied. This study was designed to evaluate the antioxidative effect of ethanolic Echinacea Purpurea (EEP) on hyperthyroidism-induced oxidative stress mice using an integrated strategy combining transcriptomics with network pharmacology analysis. Firstly, a hyperthyroidism mice model was induced via thyroxine (160 mg/kg) and EEP (1, 2, or 4 g/kg) once daily for 2 weeks. Body weight, thyroid-stimulating hormones, and oxidative stress markers were tested. Secondly, EEP regulating the potential genes at transcript level were analyzed. Thirdly, a network pharmacology based on the constituents of EEP identified using UPLC-Q-TOF-MS analysis was adopted. Finally, a joint analysis was performed to identify the key pathway. The results showed that EEP significantly changed the thyroid-stimulating hormones and oxidative stress markers. Meanwhile, RT-qPCR and Western Blotting demonstrated that the mechanism of the antioxidant effect of EEP reversed the mRNA expression of EHHADH, HMGCR and SLC27A2 and the protein expression of FABP and HMGCR in AMPK and PPAR signaling pathways. This study integrates transcriptomics with network pharmacology to reveal the mechanism of ameliorative effect of EEP on hyperthyroidism-induced oxidative stress.

Lower circulating omentin-1 is independently linked to subclinical hypothyroidism reflecting cardiometabolic risk: an observational case-control and interventional, longitudinal study

BACKGROUND

Omentin-1, a newly discovered adipokine, is implicated in the modulation of the adipose phenotype, ameliorating systemic metabolism and exhibiting anti-atherogenic, anti-oxidative, cardioprotective, anti-inflammatory and insulin-sensitizing properties. Our goal was to explore circulating omentin-1 in subclinical hypothyroidism (SH) and determine its correlations with cardiometabolic risk factors.

METHODS

In a large case-control and interventional longitudinal study, serum omentin-1, metabolic and lipid parameters, inflammatory biomarkers, classic adipocytokines and cardiovascular risk factors were assessed in 120 consecutive patients with SH and 120 healthy controls matched on age, gender and date of blood draw. Sixteen patients with SH were administered L-T4 and, after six months, circulating omentin-1 and other biomarkers were determined.

RESULTS

SH subjects presented significantly decreased circulating omentin-1 than control individuals (P<0.001). In all study participants, omentin-1 was negatively correlated with TSH, anti-thyroid antibodies, HOMA-IR, C-peptide, lipid and inflammatory biomarkers, adipokines and cardiovascular risk factors, including Framingham score and apolipoprotein B. Omentin-1 was positively associated with adiponectin and HDL-C. Circulating omentin-1 was independently associated with SH occurrence, above and beyond clinical and cardiometabolic factors (P=0.04). TSH was a negative independent predictor of serum omentin-1 levels (P<0.001). L-T4 treatment did not alter considerably the lower omentin-1 levels in treated SH patients (P=0.07).

CONCLUSIONS

Omentin-1 may be a useful non-invasive biomarker reflecting cardiometabolic risk as well as a promising therapeutic target. More mechanistic and larger prospective studies shedding light on the pathogenetic role of omentin-1 in SH are required to confirm these findings.

Update on subclinical thyroid dysfunction

Subclinical thyroid dysfunction is defined by serum thyroid-stimulating hormone (TSH) levels either greater or less than the reference range with normal thyroxine (T4) concentrations, and consists of subclinical hypothyroidism (SCH) and subclinical hyperthyroidism (SCHyper). For the proper diagnosis of SCH, it is most important to be able to correctly evaluate the serum TSH levels, which have numerous unique characteristics. We also need to be versed in TSH harmonization, which was recently launched world-wide. In this review, we will attempt to determine the best clinical approaches to the treatment of subclinical thyroid dysfunction based on recent guidelines published from several countries and novel findings of several recent large-scale clinical studies.

The Clinical Relevance of Hypothyroidism in Patients with Solid Non-Thyroid Cancer: A Tantalizing Conundrum

Hypothyroidism in patients with solid non-thyroid cancer is a tantalizing entity, integrating an intriguing thyroid hormones (THs)-cancer association with the complexity of hypothyroidism itself. The present narrative review provides a comprehensive overview of the clinical relevance of hypothyroidism in solid non-thyroid cancer. Hypothyroidism in patients with solid non-thyroid cancer is reminiscent of hypothyroidism in the general population, yet also poses distinct challenges due to the dual role of THs in cancer: promoting versus inhibitory. Close collaboration between oncologists and endocrinologists will enable the prompt and personalized diagnosis and treatment of hypothyroidism in patients with solid non-thyroid cancer. Clinical data indicate that hypothyroidism is a predictor of a decreased or increased risk of solid non-thyroid cancer and is a prognostic factor of favorable or unfavorable prognosis in solid non-thyroid cancer. However, the impact of hypothyroidism with respect to the risk and/or prognosis of solid non-thyroid cancer is not a consistent finding. To harness hypothyroidism, or THs replacement, as a personalized anticancer strategy for solid non-thyroid cancer, four prerequisites need to be fulfilled, namely: (i) deciphering the dual THs actions in cancer; (ii) identifying interventions in THs status and developing agents that block tumor-promoting THs actions and/or mimic anticancer THs actions; (iii) appropriate patient selection; and (iv) counteracting current methodological limitations.

The Association Between Subclinical Thyroid Dysfunction and Recurrence of Atrial Fibrillation After Catheter Ablation

Objective

The aim of this study was to evaluate the association between subclinical thyroid dysfunction and the recurrence of atrial fibrillation (AF) after radiofrequency catheter ablation (RFCA).

Methods

We examined the association between subclinical thyroid dysfunction and the recurrence of AF at a large university-affiliated cardiac arrhythmia center in China. Data were collected from consecutive patients who underwent RFCA for AF, excluding those with a history of hypothyroidism, hyperthyroidism, or ongoing medical treatment for hypothyroidism or hyperthyroidism, biochemically defined overt thyroid disease, and long-term use of amiodarone before admission. The primary end point was the recurrence of AF in a time-to-event analysis. We compared outcomes in patients who had subclinical hyperthyroidism or hypothyroidism with those who had euthyroid state, using a multivariable Cox model with inverse probability weighting and propensity score matching.

Results

In all, 93 patients were excluded from 435 consecutive patients who underwent RFCA for AF. Of the remaining 342 patients for the analysis, the prevalence of subclinical hyperthyroidism and subclinical hypothyroidism were 26 (7.6%) and 41 (12.0%), respectively; during a median follow-up of 489 days, 91 patients (26.6%) developed a primary end point event. In the main analysis of the multivariable Cox model, only subclinical hyperthyroidism [hazard ratio: 3.07, 95% confidence interval (CI): 1.54–6.14] was associated with an increased risk of end point event after adjusting for potential confounders. However, the association between subclinical hypothyroidism and the end point event was not significant (hazard ratio: 0.66, 95% CI: 0.31–1.43). Results were consistent either in multiple sensitivity analyses or across all subgroups of analysis. Compared with individuals with free triiodothyronine (fT3) in the lowest quintile, those with fT3 in the highest quintile had an HR of 2.23 (95% CI: 1.16–4.28) for recurrence of AF. With the increase of thyroid-stimulating hormone (TSH), a reduction in the risk of recurrence of AF was detected in the adjusted model, and the hazard ratio (HR) per standard deviation (SD) increase was 0.82 (95% CI: 0.68–0.98).

Conclusion

In this retrospective cohort study involving patients who underwent RFCA for AF, patients with subclinical hyperthyroidism were associated with a markedly higher prevalence of recurrence of AF, whereas patients with subclinical hypothyroidism had a similar recurrence rate of AF compared to those with the euthyroid state.