Metabolic changes enhance the cardiovascular risk with differentiated thyroid carcinoma--a case control study from Manipal Teaching Hospital of Nepal

Risk of Adverse Cardiovascular Outcomes in Differentiated Thyroid Cancer Survivors: A Systematic Review and Meta-Analysis

Introduction: Long-term cardiovascular (CV) risk is a concern for differentiated thyroid cancer (DTC) survivors. Methods: We performed a systematic review and meta-analysis evaluating the risks of CV mortality and morbidity in DTC survivors compared with the general population. Respective meta-analyses were conducted for data that were adjusted for relevant confounders and crude data. We searched five electronic databases from inception to October 2021, supplemented with a hand search. Two reviewers independently screened citations, reviewed full text articles, extracted data, and critically appraised the studies, with discrepancies resolved by a third reviewer. The primary outcome was CV mortality. Secondary outcomes included atrial fibrillation, ischemic heart disease, stroke, and heart failure. We estimated the relative risk (RR) and confidence intervals [CI] of outcomes using random-effects models (adjusted for age and gender), compared with the general population. Results: We reviewed 3409 unique citations, 65 full text articles, and included 7 studies. CV mortality risk was significantly increased in DTC survivors in one study adjusted for confounders-adjusted RR (aRR) 3.35 ([CI 1.66-6.67]; 524 DTC, 1572 controls). The risk of CV morbidity in DTC survivors, adjusted for risk factors, was estimated as follows: atrial fibrillation-aRR 1.66 [CI 1.22-2.27] (3 studies, 4428 DTC, I² = 75%), ischemic heart disease-aRR 0.97 [CI 0.84-1.13] (2 studies, 3910 DTC, I² = 0%), stroke-aRR 1.14 [CI 0.84-1.55] (2 studies, 3910 DTC, I² = 69%), and heart failure-aRR 0.98 [CI 0.60-1.59] (2 studies, 3910 DTC, I² = 79%). In meta-analyses of unadjusted data, the risks of CV mortality were not significantly increased but the CV morbidity risks were similar to adjusted data. Conclusions: There is limited evidence suggesting that DTC survivors may be at an increased risk of CV death and atrial fibrillation (after adjustment for confounders). We did not observe a significantly increased risk of ischemic heart disease, stroke, or heart failure. Most analyses were subject to significant heterogeneity and further research, with careful attention to CV risk factors, is needed to clarify CV risk in DTC survivors. Registration: PROSPERO CRD42021244743.

Meta-analysis of TSH suppression therapy and the risk of cardiovascular events after thyroid cancer surgery

OBJECTIVE

To investigate the relationship between TSH suppression therapy and cardiovascular events in patients with thyroid cancer after surgery.

METHODS

Pub Med, Web of Science, and Embase databases were retrieved to collect studies related to the risk of cardiovascular events in patients treated with TSH suppression after thyroid cancer surgery. RevMan statistical software was used for meta-analysis.

RESULTS

A total of 14 studies were included. The mean heart rate of patients after thyroid cancer surgery was higher than that of the control group (SMD=2.59, 95% CI: -0.37,.54), and the risk of atrial fibrillation was increased compared with the control group (RR = 1.52, 95%CI, 1.28-1.81; I = 63%). Ejection fraction and left ventricular end-diastolic diameter were not significantly different between the two groups, ejection fraction SMD = -0.10, 95% CI: -3.73, 3.52, left ventricular end-diastolic diameter SMD = -0.09, 95% CI: - 1.29, 1.11. Patients with TSH suppression after thyroid cancer had higher mean systolic blood pressure than controls (SMD = 1.97, 95% CI: -1.09, 5.03) and mean diastolic blood pressure (SMD = 1.85, 95% CI: -0.15, 3.85).

CONCLUSION

Meta-analysis concluded that TSH suppression therapy after thyroid cancer surgery increases the risk of atrial fibrillation in patients. In addition, the heart rate, systolic blood pressure and diastolic blood pressure are higher than those in the control group, and there is no significant difference in ejection fraction and left ventricular end-diastolic diameter.

Abnormal Glucose Metabolism Parameters and the Aggressiveness of Differentiated Thyroid Carcinoma: A Hospital-Based Cross-Section Study in China

PURPOSE

The correlation of abnormal glucose metabolism and thyroid carcinoma, especially the aggressiveness of thyroid cancer, still remains controversial. We conducted this study to investigate the relationship between abnormal glucose metabolism parameters and differentiated thyroid carcinoma (DTC) in the Chinese population.

MATERIALS AND METHODS

The study was designed as a hospital-based case-control study and was approved by the Ethics Committee of our hospital and registered in the Clinical Trial Protocol Registration and Results System (Registration code: NCT03006289). From January 1, 2018 to June 30, 2021, a total of 377 DTC patients were enrolled in the study. Demographic and general characteristics, details of thyroid surgery and histopathological results, hematological test indicators were collected. Glucose metabolism parameters were calculated. Variables were analyzed by t-test, ANOVA, chi-squared analysis and Fisher's exact test. Pearson bi-variate correlation and Spearman's correlation analysis were used for bi-variate analysis.

RESULTS

More than 40% of patients with DTC were multifocality, more than half were extra-glandular invasion, and nearly 85% complied by lymph node metastasis. The prevalence of diabetes mellitus (DM) was about 10.08% in DTC patients. It was found that the proportion of postprandial 2 h blood glucose ≥11.1mmol/L and HbA1c ≥6.5% was significantly higher than the known proportion of DM (17.8%, 16.7% vs. 10.08%). Additionally, 87.3% of the DTC patients in this study had varying degrees of insulin resistance. Further analysis found that higher T staging was associated with higher levels of area under curve of C-peptide (P = 0.029), insulin sensitivity index (P = 0.012) and C-peptide sensitivity index (P = 0.016). A delayed peak of insulin secretion was found to be positive related with capsule invasion (r = 0.206, P = 0.004). In patients without a DM history, homeostasis model assessment of insulin resistance (P = 0.017), insulin sensitivity index (P = 0.019) and C-peptide sensitivity index (P = 0.020) were statistic associated with T staging. Also, the glucose metabolism parameter at 3-hour after a meal was related to a larger number of metastatic lymph nodes.

CONCLUSION

Abnormal glucose metabolism, namely, DM, hyperinsulinemia and insulin resistance, were significantly associated with the carcinogensis and aggressiveness of DTC.

Cardiovascular Outcomes in Thyroid Cancer Patients Treated With Thyroidectomy: A Meta-analysis

CONTEXT

Thyroid dysfunction is associated with an increased risk of cardiovascular disease (CVD) in the general population; however, it remains controversial whether differentiated thyroid cancer (DTC) treatment, including thyroidectomy and thyroid-stimulating hormone suppression, further increases the risk of CVD.

OBJECTIVE

This study aimed to evaluate the risk of CVD in patients with DTC.

METHODS

We performed a review of observational studies on associations between DTC and cardiovascular outcomes, indexed in MEDLINE, Embase, and Web of Science. We excluded studies that evaluated CVD as comorbidity before DTC diagnosis and those that used active surveillance without thyroidectomy as an intervention. Risk estimates were pooled using random- and fixed-effects models when 3 or more studies reported on the outcome of interest. Echocardiographic and hemodynamic parameters were examined.

RESULTS

Eighteen studies were included in the quantitative analysis (193 320 cases with DTC and 225 575 healthy controls). DTC was associated with an increased risk of atrial fibrillation (pooled risk ratio [RR] = 1.55 [95% CI: 1.30-1.84]), coronary artery disease (RR = 1.10 [1.00-1.21]), cerebrovascular accidents (RR = 1.15 [1.09-1.20]), and all-cause mortality (RR = 1.95 [1.03-3.69]). DTC was associated with higher diastolic blood pressure (standardized mean difference [SMD], 0.22 [0.01-0.42]), heart rate (0.37 [0.17-0.57]), left ventricular mass index (0.66 [0.45-0.88]), and interventricular septal thickness (0.91 [0.33-1.49]) and lower early to late ventricular filling velocities (-0.42 [-0.79 to -0.05]), but not with ejection fraction.

CONCLUSION

Patients with DTC are at an increased risk of atrial fibrillation, CVD, increased heart rate, and left ventricular mass development.

High prevalence of thyroid carcinoma in patients with insulin resistance: a meta-analysis of case-control studies

The association between insulin resistance and thyroid carcinoma is controversial. We conducted this meta-analysis of association between insulin resistance and thyroid carcinoma. There were 14 studies included in this meta-analysis. Random-effect model was used to merge the weighted mean difference value of fasting serum insulin level and the pooled effect shows that the level of fasting serum insulin is higher in patients with thyroid carcinoma than those of controls (1.88, 95% CI 0.87 to 2.90, P=0.0003). Random-effect model was used to estimate the pooled weighted mean difference and it shows that thyroid carcinoma patients have a higher level of homeostasis model assessment of insulin resistance (HOMA-IR) than patients without thyroid carcinoma (0.54, 95% CI 0.29 to 0.78, P<0.0001). Fixed-effect model with the odds ratio of insulin resistance shows that insulin resistance could increase the risk of thyroid carcinoma 216% compared with participants without insulin resistance (3.16, 95% CI 2.09 to 4.77, P<0.0001). In conclusion, insulin resistance might be a risk factor for thyroid carcinoma.

Oncometabolites as biomarkers in thyroid cancer: a systematic review

INTRODUCTION

Thyroid cancer (TC) is an important common endocrine malignancy, and its incidence has increased in the past decades. The current TC diagnosis and classification tools are fine-needle aspiration (FNA) and histological examination following thyroidectomy. The metabolite profile alterations of thyroid cells (oncometabolites) can be considered for current TC diagnosis and management protocols.

METHODS

This systematic review focuses on metabolite alterations within the plasma, FNA specimens, and tissue of malignant TC contrary to benign, goiter, or healthy TC samples. A systematic search of MEDLINE (PubMed), Scopus, Embase, and Web of Science databases was conducted, and the final 31 studies investigating metabolite biomarkers of TC were included.

RESULTS

A total of 15 targeted studies and 16 untargeted studies revealed several potential metabolite signatures of TC such as glucose, fructose, galactose, mannose, 2-keto-d-gluconic acid and rhamnose, malonic acid and inosine, cholesterol and arachidonic acid, glycosylation (immunoglobulin G [IgG] Fc-glycosylation), outer mitochondrial membrane 20 (TOMM20), monocarboxylate transporter 4 (MCT4), choline, choline derivatives, myo-/scyllo-inositol, lactate, fatty acids, several amino acids, cell membrane phospholipids, estrogen metabolites such as 16 alpha-OH E1/2-OH E1 and catechol estrogens (2-OH E1), and purine and pyrimidine metabolites, which were suggested as the TC oncometabolite.

CONCLUSION

Citrate was suggested as the first most significant biomarker and lactate as the second one. Further research is needed to confirm these biomarkers as the TC diagnostic oncometabolite.

Long-term treatment-related morbidity in differentiated thyroid cancer: a systematic review of the literature

Background

Differentiated thyroid cancer (DTC) occurs in relatively young patients and is associated with a good prognosis and long survival. The management of this disease involves thyroidectomy, radioiodine therapy, and long-term thyroid-stimulating hormone suppression therapy (THST). The long-term effects of the treatment and the interaction between subclinical hyperthyroidism and long-term hypoparathyroidism are poorly understood. This review sought to examine the available evidence.

Methods

A PubMed search was carried out using the search terms “Thyroid Neoplasms” AND (“Thyroxine” OR “Hypocalcemia” OR “Thyrotropin”). Original English language articles published in the last 30 years studying the morbidity from thyroid-stimulating hormone (TSH) suppression and hypoparathyroidism following a surgery for DTC were retrieved and reviewed by 2 authors.

Results

Of the 3,000 results, 66 papers including 4,517 patients were selected for the present study. Studies reported on a range of skeletal (included in 34 studies, 1,647 patients), cardiovascular (17 studies, 957 patients), psychological (10 studies, 663 patients), and other outcomes (10 studies, 1,348 patients). Nine of 26 studies on patients who underwent THST showed a reduction in bone density, and 13 of 23 studies showed an increase in bone turnover markers. Skeletal effects were more marked in postmenopausal women. There was no evidence of increased fracture risk, and only little data were available on hypoparathyroidism. Four of five studies showed an increased left ventricular mass index on echocardiography, and one study showed a higher prevalence of atrial fibrillation (AF). There was little difference in basic physiological parameters and limited literature regarding symptoms or significant events. Six studies showed associations between long-term TSH suppression and impaired quality of life. Impaired glucose metabolism and prothrombotic states were also found in DTC patients.

Conclusion

There is limited literature regarding long-term DTC treatment-related morbidity, particularly regarding the effects of long-term hypocalcemia. Most studies have focused on surrogate markers and not on clinical outcomes. A large prospective study on defined clinical outcomes would help characterize the morbidity of treatment and stimulate research on tailoring treatment strategies.

Relationship between breast cancer and levels of serum thyroid hormones and antibodies: a meta-analysis

The breast and the thyroid are hormone responsive organs that are closely related with changes of endocrine function and glandular disease. An association between thyroid disorders and breast cancer (BC) risk has been suggested, although the results are inconclusive. The purpose of the present study was to summarize evidence supporting a relationship between BC and the level of thyroid hormones and antibodies. The MEDLINE and EMBASE electronic databases were searched for studies published between 2000 and 2014. The pooled effects were presented as weighted mean differences (WMD) with 95% confidence intervals (CI) using fixed or random effect models. We summarized the results of 8 cross-sectional studies with 4, 189 participants. The overall pooled results showed that the levels of FT3 and FT4 were significantly increased in patients with BC (WMD=1.592 pmol/l; 95% CI: 0.15-3.033 and WMD=0.461 ng/dl; 95% CI: 0.015-0.906; p=0.043). The TPOAb level in patients with BC was higher than that in the control group (WMD=81.4 IU/ml; 95% CI: 78.7-84.0; p=0.000). The overall pooled results of the TgAb with random effects analyses showed that the TgAb level was significantly increased in patients with BC (WMD=101.3 IU/ml; 95% CI: 48.7-153.9; p=0.000). The present results indicated that the serum levels of FT3, TPOAb and TgAb are significantly higher in patients with breast cancer than in healthy controls.