Gender impact on the correlations between Graves' hyperthyroidism and hyperuricemia in Chinese

Efficacy of selenium supplementation for patients with Graves' hyperthyroidism during methimazole treatment: protocol for a systematic review and meta-analysis

INTRODUCTION

The most common cause of hyperthyroidism, Graves' disease is a common organ-specific autoimmune disease. Selenium is an essential trace element of the human body that is mainly concentrated in the thyroid gland and is involved in the synthesis and metabolism of thyroid hormones. Most studies have shown that the level of selenium is closely related to the occurrence and development of thyroid diseases, and selenium supplementation can help improve thyroid function. This study aims to evaluate the efficacy of selenium supplementation for patients with Graves' hyperthyroidism during methimazole treatment.

METHODS AND ANALYSIS

We will search the electronic databases including PubMed, Web of Science, Embase, the Cochrane Library, China National Knowledge Infrastructure, Wanfang Data and Chinese Biomedical Literature, and the time was deadline to December 2023. To evaluate the efficacy of methimazole combined with selenium supplementation in the treatment of Graves' hyperthyroidism, randomised controlled trials will be included. The Cochrane Collaboration's risk of bias tool will be used to assess the quality of all included studies, and the baseline data of all the studies are extracted by the authors. A random-effects model or a fixed-effects model is used to analyse the outcomes. The primary outcomes are the levels of selenium, triiodothyronine, free thyroxine and thyroid-stimulating hormone (TSH), whereas the secondary outcomes include TSH receptor antibody, thyroid peroxidase antibody and thyroglobulin antibody.

ETHICS AND DISSEMINATION

Ethics approval is not required since no original data will be collected. The results of this study will be published in a peer-reviewed journal.

PROSPERO REGISTRATION NUMBER

CRD42023410999.

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

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

Gender variations in the impact of hyperuricemia on thyroid disorders

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

Gender and Age-Specific Differences in the Association of Thyroid Function and Hyperuricemia in Chinese: A Cross-Sectional Study

OBJECTIVE

We aimed to explore gender and age-specific influences on the association between thyroid function and hyperuricemia (HUA) in a large Chinese population.

METHODS

A total of 19,013 individuals (10,563 males and 8,450 females) were recruited. The association between HUA and thyroid function was analyzed by multivariate logistic regression, and the analyses were stratified by gender and age. Thyroid function subgroups were determined in 2 methods including thyroid status and thyroid-stimulating hormone (TSH) quartiles.

RESULTS

Overall prevalence of serum uric acid (SUA) and HUA was significantly higher in males, while TSH value and thyroid dysfunction were higher in females. Increasing trends of the TSH level in both genders as well as HUA prevalence in females were found positively along with aging. However, males showed a reduced trend in HUA risk negatively with aging. Our population showed that the risk of developing HUA in hyperthyroidism, normal euthyroidism, mild hypothyroidism, and overt hypothyroidism subgroups had adjusted ORs of 0.634, 1.229, 1.370, and 1.408, respectively, in males. Subjects in females showed a similar increased risk of HUA with ORs of 0.770, 1.198, 1.256, and 1.458, respectively. Similar tendency was observed in TSH quartiles; the above two models showed significantly higher risk of HUA in the high TSH group of males, but not of females. Aging was a significant risk factor for HUA, particularly in older females after adjusting for TSH.

CONCLUSION

The risk of HUA was positively associated with an elevation in TSH levels in both genders irrespective of age, indicating the protective effects of low TSH on HUA. Males with high TSH value were more vulnerable to suffer significant risk of HUA.

The role of oxidative stress in the pathogenesis of Graves’ orbitopathy

Graves’ disease (GD) is a chronic autoimmune condition in which the anti-thyroid stimulating hormone receptor antibodies (TRAb) activate the thyrotropin receptor (TSHR) located on thyrocytes, leading to excessive thyroid hormone production. TSHR is also expressed in extrathyroidal tissues, in particular, within the orbit. The serum levels of TRAb correlate with the severity and activity of thyroid orbitopathy (TO). TO is the most common extrathyroidal manifestation of GD. It is an autoimmune inflammation of orbital tissues, that is, extraocular muscles, orbital adipose tissue or a lacrimal gland. Increased orbital fibroblast and adipocyte proliferation, overproduction of glycosaminoglycans, as well as extraocular muscle oedema, result in increased orbital tissue volume and trigger the onset of TO symptoms. The pathophysiology of TO is complex and has not been fully unexplained to date. Orbital fibroblasts show expression of the TSHR, which is the main target of autoimmunity. It has been hypothesised that T-cell activation induced by orbital receptor stimulation by the target antibody results in orbital tissue infiltration, triggering a cascade of events which leads to the production of cytokines, growth factors and reactive oxygen species (ROS). ROS cause damage to many components of the cell: the cell membrane through the peroxidation of lipids and proteins leading to a loss of their function and enzymatic activity. Oxidative stress leads to the activation of the antioxidant system, which operates through two mechanisms: enzymatic and non-enzymatic. Assessment of the concentration of oxidative stress markers and the concentration or activity of anti-oxidative system parameters enables the evaluation of oxidative stress severity, which in the future may be utilized to assess treatment efficacy and prognosis in patients with active OT.

Thyroid Dysfunction and Dysmetabolic Syndrome: The Need for Enhanced Thyrovigilance Strategies

Thyroid dysfunction (TD) is common in metabolic disorders such as diabetes mellitus (DM), cardiovascular disease (CVD), obesity, dyslipidemia, hyperuricemia, kidney and liver dysfunctions, and polycystic ovary syndrome (PCOS). Subclinical hypothyroidism (SHypo) worsens glycemic control in patients with DM, and these patients, especially those with Type-1DM, have higher prevalence of TD. Both TD and DM increase CVD risk. Even minor alteration in thyroid hormone (TH) levels can alter cardiovascular function. While hyperthyroidism increases systolic blood pressure and leads to high-output heart failure, hypothyroidism increases diastolic blood pressure and leads to low-output heart failure. Chronic subclinical hyperthyroidism (SHyper) and SHypo both increase the risk of hypertension, coronary artery disease (CAD) events, CAD deaths, and total deaths. SHyper alters cardiac morphology and function. SHypo causes dyslipidemia and endothelial dysfunction and increases the risk for weight gain and obesity. Overweight and obese patients often have hyperleptinemia, which increases the secretion of thyroid stimulating hormone (TSH) and induces TD. Dyslipidemia associated with TD can increase serum uric acid levels. Hyperuricemia promotes inflammation and may increase the risk for dyslipidemia, atherosclerosis, and CVD. TD increases the risk for developing chronic kidney disease. In nephrotic syndrome, proteinuria is associated with urinary loss of TH leading to TD. Some correlation between TD and severity of liver disease is also seen. TD and PCOS have common risk factors and pathophysiological abnormalities. Hypothyroidism must be excluded before diagnosing PCOS. Current guidelines do not strongly recommend thyroid screening in the presence of all metabolic disorders. However, pragmatic thyrovigilance is required. Clinicians must stay alert to signs and symptoms of TD, maintain high clinical suspicion, and investigate thoroughly. Drug-induced TD should be considered when TH levels do not match clinical findings or when patients are on medications that can alter thyroid function.

Predictive Value of Thyroid Hormones for Incident Hyperuricemia in Euthyroid Subjects: The Tianjin Chronic Low-Grade Systemic Inflammation and Health Cohort Study

OBJECTIVE

Thyroid hormones (THs) play an important role in both serum uric acid (SUA) excretion and purine nucleotide metabolism. Past research mainly focused on the relationships between thyroid dysfunction and hyperuricemia. Although most subjects at risk for hyperuricemia are euthyroid, few studies have investigated the predictive values of THs on incident hyperuricemia in euthyroid adults. This study aimed to examine how free triiodothyronine, thyroxine, and thyroid-stimulating hormone are related to incident hyperuricemia in euthyroid subjects.

METHODS

Participants without baseline hyperuricemia were recruited from Tianjin Chronic Low-grade Systemic Inflammation and Health Cohort Study and followed up for ∼6 years. Thyroid function was determined by chemiluminescence immunoassay methods. Hyperuricemia was defined as SUA ≥416.5 μmol/L for males and ≥357.0 μmol/L for females. Thyroid function and SUA were assessed yearly during follow-up. Adjusted Cox proportional hazards regression models were used to assess the relationship between thyroid function and hyperuricemia.

RESULTS

The incidence rates of hyperuricemia were 109 and 50 per 1000 person-years in males and females, respectively. In males, compared with the lowest quartile, the multivariable-adjusted hazards ratios for hyperuricemia in the highest quartiles of triiodothyronine, thyroxine, and thyroid-stimulating hormone were 0.57 (0.50-0.66), 0.63 (0.54-0.73), and 1.03 (0.90-1.19) (P for trend < .0001, < .0001, and .51), respectively. However, no statistically significant correlations between thyroid function and incident hyperuricemia in females were found.

CONCLUSION

This cohort study is the first to demonstrate that higher THs are related to lower risk of incident hyperuricemia in a male population with euthyroid status.

No obvious association exists between red blood cell distribution width and thyroid function

Aim: We aimed to explore gender impacts on the associations between red blood cell distribution width (RDW) and thyroid function in the Chinese population. Methods/results: Gender impacts on the associations between RDW and thyroid function in 8424 males and 5198 females were investigated. RDW was found significantly lower in males than in females. An increasing trend of RDW along with aging was demonstrated in males. For females, an obvious decrease was shown during menopause period. From binary logistic regression, RDW displayed negative relationship with hypothyroidism in both genders as a single factor. However, if RDW was analyzed as a categorical variable (in RDW width quartiles) and as a continuous variable in models with covariates, all the odds ratios were negative, except for a weak-negative relationship with hypothyroidism in women in a continuous RDW model. Conclusion: The current study suggests that anisocytosis could be a contributing factor in thyroid dysfunction.

Gender-Specific Differences on the Association of Hypertension with Subclinical Thyroid Dysfunction

OBJECTIVE

Both hypertension and subclinical thyroid dysfunction (STD) have high prevalence and clinical importance, but their relationship is still a matter of debate. We aimed to explore gender-specific difference on the association between hypertension and STD in Chinese.

METHODS

We recruited 13,380 ostensible healthy participants (8,237 men and 5,143 women). The associations between hypertension and STD were analyzed on a gender-based setting after dividing STD into subclinical hypothyroidism, subclinical hyperthyroidism and further subgrouped euthyroidism. Crude and adjusted odds ratios of STD for hypertension were analyzed by binary logistic regression.

RESULTS

An increasing trend of hypertension prevalence was found along with aging in both genders. Yet, higher male hypertension prevalence was found until 65 years, and then it intersected with female hypertension prevalence. Women had significantly higher propensity for STD than men. Yet, in elderly participants, this gender-specific difference became less obvious. We displayed detrimental effects for subclinical hypothyroidism in both genders after multiple-covariate adjustments, yet no such effects were shown for subclinical hyperthyroidism. Moreover, females with subclinical hypothyroidism were more likely to be associated with hypertension than males, and the corresponding odds ratios were 1.619 (P < 0.01) and 1.557 (P < 0.01) and 1.557 (P < 0.01) and 1.557 (P < 0.01) and 1.557 (P < 0.01) and 1.557 (P < 0.01) and 1.557 (.

CONCLUSION

We demonstrate that hypertension is associated with subclinical hypothyroidism, but not with subclinical hyperthyroidism. Moreover, females with subclinical hypothyroidism are more likely to be associated with hypertension than males.