The Relationship between Subclinical Thyroid Disease and Cardiovascular Disease Risk Score in Koreans

Increased 10-year cardiovascular disease risk in depressed patients with coexisting subclinical hypothyroidism

Purpose

The prevalence of depressive disorder (DD) and subclinical hypothyroidism (SH) was almost twofold higher in women compared with men, both of which are confirmed to be related to cardiovascular disease (CVD) risk. The current study aimed to identify the prevalence of CVD risk factors and evaluate the 10-year CVD risk in female depressed patients with and without comorbid SH.

Methods

We recruited 1744 female inpatients with a diagnosis of DD. Venous blood samples were taken from all patients for lipid and thyroid hormones. Framingham Risk Score (FRS) was used to estimate the 10-year CVD risk.

Results

Female depressed patients with SH had increased BMI, higher Hamilton Anxiety Scale (HAMA) scores, higher LDL-C, TC, UA, and a higher 10-year CVD risk than euthyroid DD groups. Serum TSH levels and HAMA scores were critical predictive variables for 10-year CVD risk in female depressed patients with comorbid SH.

Conclusion

Our study suggests that female depressed patients with SH have a high 10-year CVD risk. Serum TSH levels and HAMA scores may be helpful to predict cardiovascular risk in female patients with SH. The increased CVD risk in female depressed patients with comorbid SH requires more attention from researchers and clinicians.

Association between oral health and thyroid disorders: A population-based cross-sectional study

OBJECTIVES

In this study, we aimed to determine the relationship between oral health status and thyroid dysfunction.

METHODS

A population-based cross-sectional analysis using data from the Korean National Health and Nutrition Examination Survey (KNHNES) was performed. We investigated the association between oral health-related parameters and the prevalence of thyroid diseases. In addition, the relationship between oral health status and thyroid function test (TFT) results was analyzed. One-way analysis of variances or chi-square test was used for comparisons between oral health-related parameters and presence of thyroid diseases. Univariable and multivariable logistic regression analyses were conducted to evaluate the associations between participants' characteristics including oral health-related parameters and the abnormal results of TFTs.

RESULTS

A total of 18,034 adults were surveyed. Histories of thyroid diseases were found to be more common in people who brushed their teeth frequently or used oral hygiene products. However, histories of periodontitis and community periodontal index (CPI) did not show significant associations with histories of thyroid diseases. Among 14,860 participants without history of thyroid disorders, people having higher CPI values demonstrated higher probabilities of abnormal TFTs (OR 1.381, 95% CI 1.241-1.537, p < .0001); however, statistical significance was not found after adjusting for the other variables.

CONCLUSIONS

Our study demonstrated that good oral health-related behavior was associated with more frequent thyroid disease history. High CPI showed a significant association with TFT abnormalities; however, the significance of this association became lower when other variables such as age and sex were adjusted. Further studies will be needed to determine how the control of oral health-related conditions actually has a causal relationship with thyroid disease/dysfunction through prospective cohort studies.

Thyroxine Alleviates Energy Failure, Prevents Myocardial Cell Apoptosis, and Protects against Doxorubicin-Induced Cardiac Injury and Cardiac Dysfunction via the LKB1/AMPK/mTOR Axis in Mice

Background

Previous studies have demonstrated that energy failure is closely associated with cardiac injury. Doxorubicin (DOX) is a commonly used clinical chemotherapy drug that can mediate cardiac injury through a variety of mechanisms. Thyroxine is well known to play a critical role in energy generation; thus, this study is aimed at investigating whether thyroxine can attenuate DOX-induced cardiac injury by regulating energy generation.

Methods

First, the effect of DOX on adenosine diphosphate (ADP) and adenosine triphosphate (ATP) ratios in mice was assessed. In addition, thyroxine was given to mice before they were treated with DOX to investigate the effects of thyroxine on DOX-induced cardiac injury. Furthermore, to determine whether the liver kinase b1 (LKB1)/adenosine 5′-monophosphate-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) axis mediated the effect of thyroxine on DOX-induced cardiac injury, thyroxine was given to DOX-treated LKB1 knockout (KO) mice.

Results

DOX treatment time- and dose-dependently increased the ADP/ATP ratio. Thyroxine treatment also reduced lactate dehydrogenase (LDH) and creatine kinase myocardial band (CK-MB) levels in both serum and heart tissue and alleviated cardiac dysfunction in DOX-treated mice. Furthermore, thyroxine reversed DOX-induced reductions in LKB1 and AMPK phosphorylation; mitochondrial complex I, III, and IV activity; and mitochondrial swelling and reversed DOX-induced increases in mTOR pathway phosphorylation and myocardial cell apoptosis. These effects of thyroxine on DOX-treated mice were significantly attenuated by LKB1 KO.

Conclusions

Thyroxine alleviates energy failure, reduces myocardial cell apoptosis, and protects against DOX-induced cardiac injury via the LKB1/AMPK/mTOR axis in mice. Thyroxine may be a new agent for the clinical prevention of cardiac injury in tumor patients undergoing chemotherapy with DOX.

Diagnosis and Management of Hypothyroidism: Addressing the Knowledge-Action Gaps

Hypothyroidism presents a large epidemiological burden in India. As a result of subtle and nonspecific clinical symptoms and signs, the condition often goes undiagnosed and is not adequately treated when it is detected. There is heterogeneity in the diagnostic and treatment approaches to hypothyroidism. As a result of the physiological changes in thyroid hormones with age and illness, it is important to tailor the diagnosis and management of this condition in specific populations including pregnant women, infants, children, geriatric patients, and those with comorbid conditions. Enhanced understanding and education of physicians and patients can help to improve the outcomes of treatment in hypothyroidism which should be focused on patient-centered care. Policies and reforms should be crafted and implemented at the national level to curb public health challenges of hypothyroidism. This publication summarizes the recommendations of a national advisory board meeting to identify and bridge the gaps in understanding of the diagnosis and treatment of hypothyroidism in India. As a complement to clinical judgment, these recommendations will foster the diagnosis and management of hypothyroidism in the community and clinics for the benefit of the patients.

FUNDING

Merck Ltd, India.