Thyroid Function, Prevalent Coronary Heart Disease, and Severity of Coronary Atherosclerosis in Patients Undergoing Coronary Angiography

Associations Between Hypothyroidism and Subclinical Atherosclerosis Among Male and Female Patients Without Clinical Disease Referred to Computed Tomography

OBJECTIVES

Hypothyroidism is recognized as a risk factor for coronary artery disease (CAD). However, reports are conflicting when the results are stratified by sex and the underlying risk of CAD. We examine the sex-specific associations of hypothyroidism with coronary calcification and plaques.

METHODS

Retrospective cross-sectional study was conducted among adult patients referred to (64 multidetector spiral) computed tomography. Those with pre-existing CAD were excluded. Hypothyroidism was defined as thyroid-stimulating hormone ≥ 4.5 mU/L. Plaques were determined based on quantification of coronary calcium and coronary computed tomography angiography.

RESULTS

A total of 2499 patients (1544 male and 955 female) were included. The prevalence of hypothyroidism was significantly higher in female than in male patients (18.0% vs 12.9%, P < .001), in all patients and those <65 years. Hypothyroidism in male patients was significantly associated with higher coronary calcium score > 0, higher coronary calcium score groups, and both soft and calcified plaques (P = .027, P = .032, P = .005, and P = .017, respectively). After adjusting for traditional coronary risk factors, the higher risk in male patients remained significant for coronary plaque but not for coronary calcium score >0 (odds ratios and CIs were 1.77, 1.08-2.90, P = .023 and .98, 0.63-1.52, P = .925, respectively). On the other hand, hypothyroidism in female patients was not significantly associated with coronary calcification nor plaques in both univariate and multivariate analyses.

CONCLUSIONS

There are sex-specific differences in the association of hypothyroidism with subclinical atherosclerosis. The higher risk of coronary plaques but not calcification in male patients was independent of traditional coronary risk factors. The lack of associations in female patients may be related to lower underlying risk of CAD.

The severity of valvular heart disease in euthyroid individuals is associated with thyroid hormone levels but not with TSH levels

Background

Abnormal thyroid function is a metabolic disorder and can lead to several complications, including cardiovascular diseases. In this study, we aimed to examine the relationship between clinical traits and outcomes and the thyroid hormone level of euthyroid individuals with valvular heart disease (VHD).

Method

The thyroid function was evaluated in 526 euthyroid VHD patients and 155 healthy control people. As well as clinical indicators were collected and analyzed.

Results

No difference in TSH levels (p>0.05) was recorded; however, fT3, TT3, and TT4 levels were lower in the euthyroid VHD patients than in healthy control(4.3 vs 4.63; 1.37 vs 1.48; 97.7 vs 102.09, respectively, all p<0.05), while the fT4 level was higher (12.91 vs 12.35, p<0.05). Moreover, all showed a continuous trend with the change of NYHA grade which does not consist of the incidence of euthyroid sick syndrome(ESS). Further analysis showed that for every 10-fold increase in BNP, fT4 increases by 83%, fT3 decreases by 30%, and TT3 decreases by 12% after being adjusted for other influencing factors. Meanwhile, adjusted fT4 was correlated with multiple worse clinical indicators, which were influenced by age.

Conclusion

Thyroid hormones are widely regulated in VHD patients even with acceptable cardiac function, except for TSH level. And the adjusted fT4 is related to worse clinical indicators and outcomes which are only recorded in patients under 53 years old.

Thyroid-stimulating hormone within the normal reference range has a U-shaped association with the severity of coronary artery disease in nondiabetic patients but is diluted in diabetic patients

Too high or too low thyroid-stimulating hormone (TSH) has been associated with the progress and prognosis of coronary artery disease (CAD). However, whether TSH within its normal reference range plays a role in the severity of CAD remains unclear. In this observational study, we explored the potential relationship of hypersensitive TSH (hs-TSH) with the severity of CAD in euthyroid patients with or without diabetes mellitus. A total of 7357 CAD patients with euthyroidism were enrolled in this study. Of those, 1997 had diabetes mellitus. The severity of CAD was evaluated through the presence of myocardial infarction (MI) and the severity of coronary lesions, which was calculated using the Gensini score (GS). Logistic regression models treating hs-TSH as a categorical variable and restricted cubic spline analyses treating it as a continuous variable were used to evaluate the associations of hs-TSH with the severity of CAD. The propensity score matching method was used to further validate the differences between diabetic and nondiabetic patients. CAD patients with diabetes mellitus had lower levels of hs-TSH (1.6 (0.97-2.53) vs 1.67 (1.00-2.64)) in serum compared with CAD patients without diabetes mellitus. Meanwhile, hs-TSH was independently related to the severity of CAD. In CAD patients with vs without diabetes mellitus, the U-shaped relationship between hs-TSH and MI was more prominent in patients without diabetes mellitus, and the significant U-shaped association between higher GS and hs-TSH remained only in nondiabetes. Therefore, hs-TSH within the normal reference range has a U-shaped association with the severity of CAD in nondiabetic patients, which is markedly diluted in diabetic patients.

A Cross-Sectional Study Examining the Parametric Thyroid Feedback Quantile Index and Its Relationship with Metabolic and Cardiovascular Diseases

Background: The usual inverse correlation between thyrotropin (TSH) and thyroid hormone disappears in syndromes of central resistance to thyroid hormone, where both are high. TSH and thyroid hormone are also simultaneously high when there is an elevation of the set point of the thyroid regulation axis. This can be estimated with indices, such as the Parametric Thyroid Feedback Quantile-based Index (PTFQI), which was designed for the general population. The PTFQI is positively associated with diabetes prevalence, but association with other pathologies has not been yet explored. The aim of this project was to explore the potential relationship of the PTFQI with metabolic and cardiovascular disease in a sample of ambulatory adult patients from Spain. Methods: A cross-sectional study was carried out among the patients who underwent thyroid hormones measurement (6434 measurements from September to November 2018 in a central laboratory in Spain). We retrospectively reviewed clinical records of a subgroup of adults aged >18 years with normal TSH and free thyroxine (fT4) belonging to groups that represent extreme PTFQI (n = 661). Individuals with known conditions interfering the thyroid axis were excluded (remaining n = 296). Logistic and linear regression models adjusted for age and sex were used to calculate odds ratio (OR) of diseases and differences of clinical parameters, and 95% confidence intervals [CI]. Results: Across levels with higher PTFQI, there was an increase in the prevalence of type 2 diabetes (High vs. Low PTFQI OR: 2.88 [CI: 1.14-7.86], p-Trend = 0.02), ischemic heart disease (16.4% vs. 0%, unadjusted Haldane-Anscombe corrected OR: 23.90 [CI: 1.36-21.48], adjusted p-Trend = 0.04), atrial fibrillation (OR: 8.13 [CI: 1.33-158.20], p-Trend = 0.05), and hypertension (OR: 3.19 [CI: 1.14-9.94], p-Trend = 0.05). While the prevalence of type 2 diabetes was similarly associated with TSH and fT4, ischemic heart disease, atrial fibrillation, and hypertension were more strongly associated with the differences in fT4 values. Conclusions: Type 2 diabetes, ischemic heart disease, atrial fibrillation, and hypertension may be associated with a higher central regulation set point for thyroid hormone. These findings should be confirmed in other populations.

Impact of persistent subclinical hypothyroidism on clinical outcomes in non-ST-segment elevation acute coronary syndrome undergoing percutaneous coronary intervention

BACKGROUND

Data on the association of subclinical hypothyroidism (SCH) with the severity of coronary artery disease and major adverse cardiovascular and cerebral events (MACCE) in patients with non-ST-segment elevation acute coronary syndrome (NSTE-ACS) after percutaneous coronary intervention (PCI) are limited and conflicting.

OBJECTIVE

We established the baseline rate of SCH and followed the trajectory of thyroid-stimulating hormone (TSH) values during and after hospitalisation for PCI for up to six months and determined whether persistent SCH was associated with the severity of coronary artery disease and MACCE in patients with NSTE-ACS after PCI.

DESIGN

Population-based prospective cohort study.

PATIENTS

We included patients with NSTE-ACS who underwent PCI with simple balloon angioplasty or stent implantation for coronary heart disease.

MEASUREMENTS

Thyroid function tests of patients before PCI and 1 day, 1 week, 1 and 6 months after PCI were performed. Cases showing transient SCH were excluded. Patients were divided into two groups based on the results of four TSH tests: 0.27-4.2 mIU/L (n = 1472, 89.7%) and >4.2 mIU/L (n = 170, 10.4%). The risk factors for the severity of coronary artery lesions were estimated using multinomial logistic regression analysis. Univariate and multivariate Cox regression analyses were used to study the relationship between TSH and MACCE.

RESULTS

Among 1642 patients, there were 1070 males (65.2%) and 572 females (34.8%), with an average age of 62.5 ± 9.6 years. SCH patients had a wider range of diseased vessels and a higher number of diseased vessels (p < .05). TSH level was an independent risk factor for moderate [odds ratio (OR) = 1.144, 95% confidence interval (95% CI): 1.057-1.237, p = .001] and severe (OR = 1.131, 95% CI: 1.043-1.226, p = .003) coronary artery lesions. After adjusting for covariates, the risk of MACCE [hazard ratio (HR): 4.067, p < .001], nonfatal myocardial infarction (HR: 14.724, p = .003), and unplanned PCI (HR: 5.028, p < .001) were higher in the SCH group than in the euthyroidism group. There were no significant differences in the incidence of heart failure (HR: 6.012, p = .175), nonfatal stroke (HR: 2.039, p = .302), unplanned coronary artery bypass grafting (CABG) (HR: 1.541, p = .57), or cardiac death (HR: 2.704, p = .375) between the two groups.

CONCLUSIONS

Preoperative TSH levels and changes in thyroid hormone levels several months post-PCI in NSTE-ACS patients are highly significant in practice. Persistent SCH is associated with severe coronary artery lesions and MACCE, and may be a predictor for evaluating the prognosis of PCI-treated NSTE-ACS patients.

The importance of stratifying ischemic risk by using the Duke score in women with ischemic heart disease and hypothyroidism before inclusion in cardiovascular rehabilitation programs

Introduction: The relationship between abnormal thyroid function and coronary heart disease has been known for a long time, and particularly, hypothyroidism is associated with an increased risk of cardiovascular disease. The aim of this study was to evaluate the ischemic risk by using the Duke score in women with ischemic heart disease and associated hypothyroidism before inclusion in cardiovascular rehabilitation program. Materials and methods: We included in the study 150 female patients admitted to the Cardiology Department of the Clinical Rehabilitation Hospital Cluj-Napoca. All the patients included had ischemic heart disease and performed an exercise stress testing to evaluate the effort capacity and also to stratify the ischemic risk by calculating the Duke Score. After dosing the thyroid stimulating hormone (TSH) we divided the patients in two groups: with hypothyroidism and a control group. Results: Patients with hypothyroidism were more frequently hypertensive, (98% vs 87%, p-0.035), and they had diabetes mellitus in a higher proportion (51% vs 22%, p-0.005). HDL cholesterol was significantly decreased in the group of patients with hypothyroidism: 40.36±10.39mg/dl vs 44.85±10.29mg/dl (p-0.01). Regarding the ischemic risk assessed by the Duke score, the statistically significant differences between the two groups were registered only for the category of high-risk patients, 5.55% vs 18% (p-0.048). Also, the TSH value was higher in the group with high-risk Duke score, 4.21±3.73µIU/ml, compared to the moderate-risk score group, 1.95±1.12µIU/ml(p-0.05). Conclusion: In women with ischemic heart disease, assessing thyroid function can be useful to identify patients at high risk of ischemia. Patients with hypothyroidism tend to have a higher prevalence of cardiovascular risk factors, a higher ischemic risk objectified by the Duke score and more commonly multivascular coronary lesions. For these patients, the inclusion in cardiovascular rehabilitation programs is essential, but it is very important that the programs to be customized for each patient. Keywords: coronary heart disease in women, exercise ECG, Duke score, ischemic risk, hypothyroidism, cardiovascular rehabilitation programs

Comparing Levels of Metabolic Predictors of Coronary Heart Disease between Healthy Lean and Overweight Females

Screening for the metabolomic signature of coronary heart disease (CHD) before disease onset could help in early diagnosis and potentially disease prevention. In this study, the levels of 17 CHD metabolic biomarkers in apparently healthy overweight females were compared to lean counterparts, and their associations with conventional clinical risk factors were determined. Clinical and metabolic data from 200 apparently healthy non-obese Qatari females were collected from Qatar Biobank (discovery cohort). Logistic regression was used to assess the association between body mass index (BMI) groups and 17 CHD metabolic biomarkers, and receiver operating characteristic (ROC) analysis was used to evaluate the prognostic value of CHD metabolic biomarkers in overweight. Stepwise linear regression was performed to identify the classical risk factors associated with CHD metabolites differentiating the two BMI groups. Validation of the association of CHD metabolic biomarkers with BMI groups was performed in 107 subjects (replication cohort). Out of the tested CHD metabolic biomarkers, five were significantly different between lean and overweight females in the discovery cohort (AUC = 0.73). Among these, the association of mannose, asparagine, and linoleate with BMI groups was confirmed in the replication cohort (AUC = 0.97). Significant correlations between predictors of CHD in overweight healthy women and classical risk factors were observed, including serum levels of cholesterol, testosterone, triiodothyronine, thyroxine, creatinine, albumin, bilirubin, glucose, c-peptide, uric acid, calcium and chloride. Apparently, healthy overweight females exhibit significantly different levels of specific CHD metabolites compared to their lean counterparts, offering a prognostic potential with preventative value.

The Role of Thyroid Diseases and their Medications in Cardiovascular Disorders: A Review of the Literature

The association between thyroid disease and cardiovascular manifestations is significant and undeniable. Previous studies have explained several aspects of the effects of thyroid hormone on the heart and cardiovascular system. Accordingly, both hyper and hypothyroidism can cause important alterations in cardiac rhythm, output and contractility as well as vascular resistance and blood pressure. Since treating the thyroid abnormality, especially in its initial stages, could lead to a significant improvement in most of its resultant cardiovascular disturbances, early suspicion and recognition of thyroid dysfunction, is necessary in patients with cardiovascular manifestations. In this in-depth review, we discuss the physiological roles as well as the effects of abnormal levels of thyroid hormones on the cardiovascular system. We also review the effects of the medications used for the treatment of hyper and hypothyroidism on cardiac function. In the end, we discuss the association between thyroid function and amiodarone, an effective and frequently-used antiarrhythmic drug, because of its well-known effects on the thyroid.

Correlation of Triiodothyronine Level with In-Hospital Cardiac Function and Long-Term Prognosis in Patients with Acute Myocardial Infarction

Objective

The pathophysiologic mechanism of how thyroid function is related to the development and prognosis of acute myocardial infarction (AMI) remains under explored, and there has been a lack of clinical investigations. In this study, we investigate the relationship between triiodothyronine (T3) level and cardiac ejection fraction (EF) as well as probrain natriuretic peptide (NT-proBNP) on admission and subsequent prognosis in AMI patients.

Methods

We measured admission thyroid function, NT-proBNP, and EF by echocardiography in 345 patients diagnosed with AMI. Simple and multiregression analyses were performed to investigate the correlation between T3 level and EF as well as NT-proBNP. Major adverse cardiovascular events (MACE), including new-onset myocardial infarction, acute heart failure, and cardiac death, were documented during the follow-up. 248 participants were separated into three groups based on T3 and free triiodothyronine (FT3) levels for survival analysis during a 2-year follow-up.

Results

345 patients diagnosed with AMI were included in the initial observational analysis. 248 AMI patients were included in the follow-up survival analysis. The T3 levels were found to be significantly positively correlated with EF (R square = 0.042, P < 0.001) and negatively correlated with admission NT-proBNP levels (R square = 0.059, P < 0.001), which is the same with the correlation between FT3 and EF (R square = 0.053, P < 0.001) and admission NT-proBNP levels (R square = 0.108, P < 0.001). Kaplan-Meier survival analysis revealed no significant difference with regard to different T3 or FT3 levels at the end of follow-up.

Conclusions

T3 and FT3 levels are moderately positively correlated with cardiac function on admission in AMI patients but did not predict a long-time survival rate. Further studies are needed to explain whether longer-term follow-up would further identify the prognosis effect of T3 on MACE and all-cause mortality.

Levels of serum thyroxine, triidothyronine and thyrotropin in patients with acute myocardial infarction

Objective

To determine the levels of serum thyroxine (T3, T4), triiodothyronine and thyrotropin in patients with acute myocardial infarction (AMI).

Methods

It was an observational prospective study and 60 patients (both males and females) of AMI, (diagnosed by ECG & cardiac enzymes.) were included. Serum thyroid stimulating hormone (TSH), Free T3 and Free T4 were measured and relevant data was entered into a predesigned proforma.

Results

FT3 levels were below the reference range in 56.7% cases while both the FT4 and TSH values were found to be the lower limit of normal range. When the decrease in FT3 was correlated with the duration of illness, it was found that significant inverse correlation existed between FT3 value and the duration of illness and linear regression line was obtained. No such correlation existed between FT4 and TSH values.

Conclusion

Thyroid hormone levels (FT3) decreases in AMI and this change is associated with the duration of illness.

Hyperthyroidism in patients with ischaemic heart disease after iodine load induced by coronary angiography: Long-term follow-up and influence of baseline thyroid functional status

OBJECTIVE

To study the effect of a iodine load on thyroid function of patients with ischaemic heart disease (IHD) and the long-term influence of unknown subclinical hyperthyroidism.

CONTEXT

Subclinical hyperthyroidism is considered an independent risk factors for cardiovascular morbidity of patients with IHD. They routinely undergo coronary angiography with iodine contrast media (ICM) which may induce or even worsen hyperthyroidism.

DESIGN

A cross-sectional study followed by a longitudinal study on patients with subclinical hyperthyroidism.

PATIENTS

810 consecutive IHD outpatients without known thyroid diseases or treatment with drugs influencing thyroid activity undergoing elective coronary angiography.

MEASUREMENTS

We evaluated thyroid function either before and 1 month after ICM; patients with thyrotoxicosis at baseline or after ICM were then followed up for 1 year.

RESULTS

58 patients had hyperthyroidism at baseline (HB, 7.2%), independently associated to FT4 levels, thyroid nodules and family history of thyroid diseases. After ICM, the prevalence of hyperthyroidism was 81 (10%). Hyperthyroidism after ICM was positively predicted by baseline fT4 levels, thyroid nodules, age over 60, male gender, family history of thyroid diseases. Three months after ICM, 34 patients (4.2%) still showed hyperthyroidism (22 from HB, 13 treated with methimazole). One year after ICM, hyperthyroidism was still present in 20 patients (2.5%, all from HB, 13 treated).

CONCLUSIONS

The prevalence of spontaneous subclinical hyperthyroidism in IHD is surprisingly elevated and is further increased by iodine load, particularly in patients with thyroid nodules and familial history of thyroid diseases, persisting in a not negligible number of them even after one year.

Impact of Hypothyroidism on Occurrence and Outcome of Acute Coronary Syndrome from the National Inpatient Sample

Thyroid hormones have a profound effect on cardiovascular physiology. We utilized a large national inpatient database in the United States (National Inpatient Sample) to study hypothyroidism in relation to the prevalence of coronary heart disease (CHD) and its impact on outcomes (mortality, the length of stay, and hospitalization cost) in the acute coronary syndrome (ACS) subgroup of CHD patients. We found that although hypothyroidism has an increased association with CHD (odds ratio [OR] 1.11, 95% confidence interval [CI] 1.09 to 1.12, p <0.001), the odds of developing ACS in these CHD patients is lower in the hypothyroid group (OR 0.71, 95% CI 0.70 to 0.72, p <0.001) after adjusting for multiple risk factors. Additionally, patients with hypothyroid ACS have a reduced odds of in-hospital mortality (OR 0.86, 95% CI 0.83 to 0.88, p <0.001), shorter length of stay by 0.45 days (p <0.001), and lower hospitalization cost by $1,531.45 (p <0.001) compared with the euthyroid group. Our findings suggest that hypothyroidism has an increased CHD risk but a lower risk of development of ACS in hospitalized CHD patients, as well as a better short-term prognosis including ACS-associated mortality.