Increased risk of venous thromboembolism among patients with hyperthyroidism: a systematic review and meta-analysis of cohort studies

Efficacy and safety of Danggui Liuhuang Decoction combined with antithyroid drugs for hyperthyroidism: A systematic review and meta-analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Hyperthyroidism is a prevalent clinical endocrine disorder. Danggui Liuhuang Decoction (DGLHD), a traditional Chinese herbal medicine formula, has shown potential benefits for patients with hyperthyroidism in recent studies. However, the clinical efficacy and safety of DGLHD have not been systematically evaluated. To address this, a systematic review and meta-analysis are necessary to comprehensively evaluate its efficacy and safety in treating hyperthyroidism.

AIM OF THE STUDY

To evaluate the efficacy and safety of DGLHD in treating hyperthyroidism.

MATERIALS AND METHODS

A comprehensive search of eight databases was conducted from their inception to November 2023 to identify randomized controlled trials (RCTs) comparing DGLHD combined with antithyroid drugs (ATDs) to ATDs alone. The quality of the included studies was assessed using the Cochrane Risk of Bias Assessment Tool. A meta-analysis was conducted using Revman 5.3 software, while publication bias was evaluated with Stata 16.0 software. The certainty of the evidence was assessed using the GRADE system.

RESULTS

Overall, 20 RCTs involving 1757 patients with hyperthyroidism were included in this analysis. The methodological quality was generally low. The meta-analysis revealed that, compared to ATDs alone, the combination of DGLHD with ATDs was more effective in reducing free triiodothyronine (FT3) [standardized mean difference (SMD) = -0.80, 95% confidence interval (CI): -1.31 to -0.28, P = 0.002], free thyroxine (FT4) [SMD = -1.47, 95% CI: -1.99 to -0.94, P < 0.00001], Traditional Chinese Medicine (TCM) syndrome scores [mean difference (MD) = -3.65, 95% CI: -4.68 to -2.62, P < 0.00001], and adverse events [relative risk (RR) = 0.23, 95% CI: 0.15 to 0.36, P < 0.00001]. Additionally, combining DGLHD with ATDs led to an improvement in thyroid-stimulating hormone (TSH) levels [SMD = 2.75, 95% CI: 1.37 to 4.13, P < 0.0001] and increased the effectiveness rate of TCM syndrome [RR = 1.20, 95% CI: 1.08 to 1.34, P = 0.001]. However, other outcomes, such as recurrence rates and quality of life scores, could not be analyzed through meta-analysis owing to the limited number of included studies.

CONCLUSION

Combining DGLHD with ATDs may alleviate clinical symptoms, enhance thyroid function, and reduce adverse events in patients with hyperthyroidism. Moreover, this treatment appears to be safe for clinical use. However, owing to the limited quantity and quality of the included studies, these conclusions require further validation through more large-sample, multicenter, high-quality RCTs.

Impact of thyroid function on coagulation and venous thromboembolism: a two-sample mendelian randomization study

OBJECTIVE

The association between thyroid function, coagulation and venous thromboembolism (VTE) has been reported in observational studies with conflicting findings. This study aimed to elucidate the causal effects of thyroid function on coagulation and VTE from a genetic perspective.

METHODS

Two sample Mendelian randomization analysis was conducted using summary statistics from genome-wide association studies in a European population. Coagulation status was associated with nine coagulation-related factors (F VIII, F IX, F XI, Fibrinogen, Antithrombin-III, Thrombomodulin, Plasminogen activator inhibitor-1, Protein C and Protein S). Inverse variance weighting with random effect method was used as the main analytic approach with MR-Egger, weighted median, simple mode and weighted mode methods serving as complements. Sensitivity analyses including heterogeneity test, horizontal pleiotropy test and leave-one-out analysis were conducted to further assess the reliability of results.

RESULTS

No genetic causal effects of thyroid function on VTE (including pulmonary embolism and deep venous thrombosis) were found. Genetically, hyperthyroidism was suggestively related to decreased Antithrombin-III (β: -0.04 [95% CI: -0.06 to - 0.01], p = 0.010) and Protein C (β: -0.03 [95% CI: -0.06 to 0.00], p = 0.045). No notable associations were observed between other thyroid function parameters and coagulation-related factors.

CONCLUSION

We provide suggestive genetic evidence supporting the causal effect of hyperthyroidism on decreased level of anticoagulant factors including Antithrombin-III and Protein C. However, whether this genetic causality could lead to clinically significant hypercoagulable state and increased risk of VTE in hyperthyroid population needs to be further addressed.

A phenome-wide approach to identify causal risk factors for deep vein thrombosis

Deep vein thrombosis (DVT) is the formation of a blood clot in a deep vein. DVT can lead to a venous thromboembolism (VTE), the combined term for DVT and pulmonary embolism, a leading cause of death and disability worldwide. Despite the prevalence and associated morbidity of DVT, the underlying causes are not well understood. Our aim was to leverage publicly available genetic summary association statistics to identify causal risk factors for DVT. We conducted a Mendelian randomization phenome-wide association study (MR-PheWAS) using genetic summary association statistics for 973 exposures and DVT (6,767 cases and 330,392 controls in UK Biobank). There was evidence for a causal effect of 57 exposures on DVT risk, including previously reported risk factors (e.g. body mass index-BMI and height) and novel risk factors (e.g. hyperthyroidism and varicose veins). As the majority of identified risk factors were adiposity-related, we explored the molecular link with DVT by undertaking a two-sample MR mediation analysis of BMI-associated circulating proteins on DVT risk. Our results indicate that circulating neurogenic locus notch homolog protein 1 (NOTCH1), inhibin beta C chain (INHBC) and plasminogen activator inhibitor 1 (PAI-1) influence DVT risk, with PAI-1 mediating the BMI-DVT relationship. Using a phenome-wide approach, we provide putative causal evidence that hyperthyroidism, varicose veins and BMI enhance the risk of DVT. Furthermore, the circulating protein PAI-1 has a causal role in DVT aetiology and is involved in mediating the BMI-DVT relationship.

Association between thyroid dysfunction and venous thromboembolism: A systematic review and meta-analysis

BACKGROUND

Thyroid dysfunction plays an important role in the development of cardiovascular disease. However, its relationship with venous thromboembolism (VTE) remains unclear. We performed a meta-analysis of published cohort and case-control studies to investigate the association between thyroid dysfunction and VTE comprehensively.

METHODS

Three reviewers independently searched EMbase, PubMed, China national knowledge infrastructure, and Cochrane Library databases for relevant articles from the time of database establishment to 01 October 2022 and identified all studies on thyroid dysfunction and VTE as studies of interest. Of the 2418 publications retrieved, we identified 10 articles with 15 studies that met our selection criteria. Pooled ORs and 95% confidence intervals were calculated using fixed- or random-effect models.

RESULTS

We pooled 8 studies by a fixed-effect model, which suggested an increased risk of VTE in patients with (subclinical) hyperthyroidism (OR 1.33, 95% CI: 1.29-1.38). In the other 7 studies on patients with (subclinical) hypothyroidism, the risk was similarly increased when pooled by a random-effect model (OR 1.52, 95% CI: 1.23-1.89). After sensitivity analysis and risk of bias analysis, the risk of VTE was still increased in both (subclinical) hyperthyroidism (OR 1.322, 95% CI: 1.278-1.368) and (subclinical) hypothyroidism (OR 1.74, 95% CI: 1.41-2.16).

CONCLUSION

Patients with thyroid dysfunction have an increased risk of VTE. Therefore, it is recommended to perform thyroid function screening routinely in patients at high risk of VTE.

Effects of Hyperthyroidism on Venous Thromboembolism: A Mendelian Randomization Study

Objective

Observational studies show the correlation between thyroid dysfunction and risk of venous thromboembolism. However, the causal effects remain uncertain. Our study was conducted to evaluate whether thyroid function and dysfunction were causally linked to the risk of venous thromboembolism.

Methods

Publicly available summary data of thyrotropin (TSH) and free thyroxine (FT4), hypothyroidism, and hyperthyroidism were obtained from the ThyroidOmics Consortium and the UK Biobank. With single nucleotide polymorphisms (SNPs) as instrumental variables, the casual effects of genetically predicted TSH and FT4 and hypo- and hyperthyroidism on venous thromboembolism outcome were estimated through Mendelian randomization analysis methods (inverse variance weighted (IVW), MR-Egger, weighted median, simple mode, and weighted mode). Cochran's Q test was performed to evaluate the heterogeneity and horizontal pleiotropy.

Results

Our study selected 15 FT4-, 36 TSH-, 3 hyperthyroidism-, and 79 hypothyroidism-associated SNPs as instrumental variables. The IVW analysis results showed that the odds ratio of venous thromboembolism for hyperthyroidism was 1.124 (95% confidence interval: 1.019-1.240; p = 0.019), demonstrating the casual effect of hyperthyroidism not FT4, TSH, and hypothyroidism on venous thromboembolism. No heterogeneity or horizontal pleiotropy was observed according to Cochran's Q test.

Conclusion

Our Mendelian randomization analysis supports the causal effect of hypothyroidism on risk of venous thromboembolism. There is no evidence that genetically predicted TSH, FT4, and hypothyroidism have casual effects on venous thromboembolism. Future studies should be conducted to elucidate the underlying pathophysiological mechanisms.

Associations between hyperthyroidism and adverse obstetric and neonatal outcomes: A study of a population database including almost 17,000 women with hyperthyroidism

OBJECTIVE

Large population-based studies on maternal hyperthyroidism's effect on antepartum, intrapartum, and neonatal complications are few. Most of these studies were small or did not evaluate a broad scope of possible complications. Therefore, a large population-based cohort study was conducted to study the associations between maternal hyperthyroidism and pregnancy and perinatal complications.

DESIGN

This is a retrospective population-based cohort study utilizing data from the Healthcare Cost and Utilization Project-Nationwide Inpatient Sample over 11 years from 2004 to 2014.

PATIENTS

16,984 deliveries to women with hyperthyroidism and 9,079,804 deliveries to mothers who did not suffer of hyperthyroidism.

METHODS

A cohort of all deliveries between 2004 and 2014 inclusively was created. Within this group, all deliveries to women with hyperthyroidism were the study group (n = 16,984) and the remaining deliveries were categorized as nonhyperthyroidism births and comprised the reference group (n = 9,079,804). The main outcome measures were pregnancy and perinatal complications.

RESULTS

Maternal hyperthyroidism was associated with several pregnancy and perinatal complications, including increased risks of gestational hypertension (adjusted odds ratio [aOR]: 1.236, 95% confidence interval [CI]: 1.045-1.462, p = .013) and preeclampsia (aOR: 1.190, 95% CI: 1.006-1.408, p = .042). These patients are more likely to experience preterm premature rupture of membranes (aOR: 1.322, 95% CI: 1.007-1.735, p = .044), preterm delivery (aOR: 1.287 95% CI: 1.132-1.465, p < .001), placental previa (aOR: 1.527, 95% CI: 1.082-2.155, p = .016), and suffer from venous thromboembolism (aOR: 2.894, 95% CI: 1.293-6.475, p = .010). As for neonatal outcomes, small for gestational age and stillbirth were more likely to occur in the offspring of women with hyperthyroidism (aOR: 1.688, 95% CI: 1.437-1.984, p < .001 and aOR: 1.647, 95% CI: 1.109-2.447, p = .013, respectively).

CONCLUSIONS

Women with hyperthyroidism are more likely to experience pregnancy, delivery, and neonatal complications. We found an association between hyperthyroidism and hypertensive disorders, preterm delivery, and intrauterine fetal death.

2022 Update on Clinical Management of Graves Disease and Thyroid Eye Disease

The management of hyperthyroidism and extrathyroidal manifestations of Graves disease remains complex. Considerations that include patient preference, age, comorbidity, pregnancy, tobacco smoking, and social determinants of health must all be weaved into a cohesive management plan. A multidisciplinary team is required to manage all aspects of Graves disease, particularly thyroid eye disease, for which new therapeutic options are now available.

Possible Contributions of Nongenomic Actions of Thyroid Hormones to the Vasculopathic Complex of COVID-19 Infection

BACKGROUND

Integrin αvβ3 is a cell membrane structural protein whose extracellular domain contains a receptor for L-thyroxine (T4). The integrin is expressed in rapidly dividing cells and its internalization is prompted by T4. The protein binds viruses and we have raised the possibility elsewhere that action of free T4 (FT4)-when he latter is increased in the nonthyroidal illness syndrome (NTIS) known to complicate COVID-19 infecction-may enhance cellular uptke of SARS-CoV-2 and its receptor.

OBJECTIVE

Because T4 also acts nongenomically via the integrin to promote platelet aggregation and angiogenesis, we suggest here that T4 may contribute to the coagulopathy and endothelial abnormalities that can develop in COVID-19 infections, particularly when the lung is primary affected.

DISCUSSION AND CONCLUSIONS

Elevated FT4 has been described in the NTIS of COVID-19 patients and may be associated with increased illness severity, but the finding of FT4 elevation is inconsistent in the NTIS literature. Circulating 3,5',3'-triiodo-L-thyronine (reverse T3, rT3) are frequently elevated in NTIS. Thought to be biologically inactive, rT3in fact stimulates cancer cell proliferation via avb3 and also may increase actin polymerization. We propose here that rT3 in the NTIS complicating systemic COVIF-19 infection may support coagulation and disordered blood vessel formation via actin polymerization.

Unraveling the Molecular Basis for Successful Thyroid Hormone Replacement Therapy: The Need for New Thyroid Tissue- and Pathway-Specific Biomarkers

Thyroid function is conventionally assessed by measurement of thyroid-stimulating hormone (TSH) and free circulating thyroid hormones, which is in most cases sufficient for correct diagnosis and monitoring of treatment efficiency. However, several conditions exist, in which these parameters may be insufficient or even misleading. For instance, both, a TSH-secreting pituitary adenoma and a mutation of thyroid hormone receptor β present with high levels of TSH and circulating hormones, but the optimal treatment is substantially different. Likewise, changes in thyroid hormone receptor α signaling are not captured by routine assessment of thyroid status, as serum parameters are usually inconspicuous. Therefore, new biomarkers are urgently needed to improve the diagnostic management and monitor treatment efficiency for e. g., replacement therapy in hypothyroidism or thyroid hormone resistance. By comparing animal models to human data, the present minireview summarizes the status of this search for new tissue- and pathway-specific biomarkers of thyroid hormone action.