Relationships of Thyroid Hormones in the Normal Range to Coronary Artery Disease in Different Age Groups

Objective To investigate the effect of age on the association between normal thyroid hormone level and coronary artery disease (CAD). Methods A total of 1163 euthyroid patients undergoing coronary angiography (CAG) from January 2013 to June 2014 were enrolled and categorized into 2 groups: the young and middle-aged group (<60 years, n=602) and the elderly group (≥60 years, n=561), and each group was sub-grouped into the CAD and non-CAD group according to CAG. Height, body weight, and levels of serum lipid, fasting blood glucose, glycosylated hemoglobin, free triiodothyronine (FT3), free thyroxine (FT4) and thyroid-stimulating hormone (TSH) were measured. Results In the youth and middle-aged group, 309 patients (51.3%) were diagnosed as CAD, and there was no significant difference in the levels of FT3, FT4 and TSH between CAD and non-CAD patients 〔(5.3±0.6)mmol/L vs. (5.3±0.5)mmol/L, (11.8±1.9)mmol/L vs. (11.8±1.8) mmol/L, (2.0±1.1) mIU/L vs. (2.0±1.0)mIU/L, all P>0.05〕. In the elderly group, 357 patients (63.6%) were diagnosed as CAD, and the FT3 level was lower in the CAD patients than in the non-CAD patients〔(5.1±0.6)mmol/L vs. (5.2±0.5)mmol/L, P<0.01〕. Logistic regression demonstrated that FT3 was an independent influencing factor for CAD in elderly patients (OR=0.564, P<0.01). Conclusions The association between normal thyroid hormones levels and CAD varies along with age. Thyroid hormones have no relationships with CAD in the young and middle-aged people. The decline of FT3 level may increase the risk of CAD in the elderly. Key words: Thyroid hormones; Coronary disease; Age factor

P1536Does free thyroxine (fT4) predict risk of atherosclerotic cardiovascular disease (ASCVD)?

Studies on the relationship between thyroid stimulating hormone (TSH) within the reference range and coronary artery disease (CAD) have produced conflicting results. Furthermore, the effect of age on this relationship has never been explored. The aim of this study was to investigate the association between TSH levels and CAD among euthyroid subjects and whether age influenced this relationship. A total of 318 subjects who underwent coronary angiography were included. Serum TSH, T3, T4, lipid, blood glucose and creatinine levels were measured and compared between the groups with and without CAD. Age-stratified analysis and multivariate logistic regression analysis were performed. Levels of TSH, T3 and T4 did not differ significantly between CAD (n=196) and non-CAD group (n=122) (TSH: 1.77 ± 0.99 vs 1.89 ± 0.98 mIU/L, T3: 1.45 ± 0.36 vs 1.51 ± 0.35 nmol/L, T4: 100.06 ± 20.49 vs 103.95 ± 24.06 nmol/L, respectively) when comparisons were performed among all subjects. A significant between-group difference in levels of TSH was observed among subjects less than or equal to 65 years old (CAD group: n=121, non-CAD group: n=106), with higher TSH levels in CAD group (2.03 ± 0.94 vs 1.75 ± 0.97 mIU/L, adjusted p=0.024). Multivariate logistic regression analysis revealed that elevated level of TSH was an independent predictor for CAD (odds ratio: 1.512, p=0.011). No significant between-group difference in TSH levels was observed among subjects older than 65 years (CAD group: n=75, non-CAD group: n=16). The results showed that higher levels of TSH within the reference range were independently associated with the presence of CAD only among subjects less than or equal to 65 years old, suggesting age might influence the relationship.

Antidepressant-Resistant Depression in Patients With Comorbid Subclinical Hypothyroidism or High-Normal TSH Levels.

Objective To explore the correlation between thyroxine hormone and the severity of coronary artery disease (CAD).Methods 158 patients with coronary adisease were entered consecutively into the study.They were separated into control group (absence of CAD,n=98)and CAD group (presence of CAD,n=60).Based on the number of vessel disease,CAD group was further divided into three sub-groups:single-vessel CAD subgroup (n=30),bi-vessel CAD subgroup (n=15) and multi-vessel CAD subgroup (n=15).Serum free triiodothyronine (fT3),free thyroxine (fT4),thyroid stimulating hormone (TSH) were tested by electrochemiluminescence; high density lipoprotein cholesterol (HDL-C) and total cholesterol (TC) weremeasured by cholesterol oxidase method; and Gensini scoring system was used to evaluate the degree of coronary artery stenosis.Results The levels of fT3 in both bi-vessel CAD and multi-vessel subgroups were higher than those in control group (t=1.947,6.415,both P＜0.05).And the level of fT4 in multi-vessel subgroup was also higher than that in control group (t=3.026,P＜0.05).fT3 was an independent risk factor of CAD using Logistic regression model.In addition,fT3 was negatively correlated with Gensini scoring inmultiple linear regressions.Gensini scores would increase by 1 as long as the level oft fT3 decreases 0.234 pmol/L.Conclusions fT3 level decreased in patients with CAD,and correlated with the severity of CAD.Gensiniscores would increase 1 as long as fT3 decreases 0.234 pmol/L,which could be supposed as a sensitive predictor of CAD. Key words: Thyroid hormones; Coronary artery disease; Gensini scoring

Thyroid hormone has many effects on the heart and cardiovascular system. Thyrotoxicosis is associated with increased cardiovascular morbidity and mortality, primarily due to heart failure and thromboembolism. However, the relationship between thyroid hormone excess and the cardiac complications of angina pectoris and myocardial infarction remains largely speculative. Moreover, few studies have been reported on the effect of thyroid hormone levels within normal range on coronary artery disease (CAD). Therefore we examined the association of thyroid function with coronary artery diseases in euthyroid angina patients. Total 192 subjects (mean age; 60.8 yrs) were enrolled in which coronary angiograms were performed due to chest pain. We measured free thyroxine (FT(4)), thyroid stimulating hormone (TSH), serum lipid levels and high-sensitivity C-reactive protein (hsCRP) levels and analyzed their association with the presence of CAD. Serum FT(4) levels were higher in patients with CAD compared with the patients without CAD (1.31 +/- 0.30 vs 1.20 +/- 0.23, p = 0.006), and high FT(4) level was associated with the presence of multi-vessel disease. Multivariate analysis showed that age (odds ratio (OR) 1.04; 95% confidence interval (CI) 1.01-1.07, p = 0.007), hypertension (OR 2.04; 95% CI 1.06-3.90, p = 0.036) and FT(4) (OR 4.23; 95% CI 1.12-15.99, p = 0.033), were the determinants for CAD. The relative risk (RR) for CAD in highest tertile of FT(4) showed increased risk compared with the lowest tertile (RR 1.98; 95% CI 0.98-3.99, p<0.001). Our study showed that FT(4) levels were associated with the presence and the severity of CAD. Also, this study suggests that elevated serum FT(4) levels even within normal range could be a risk factor for CAD. Further studies will be necessary to confirm the relationship of thyroid function and CAD.

BackgroundTriglyceride-glucose (TyG) index is an effective indicator in indentifying in pre-diabetes, diabetes, and coronary artery disease (CAD). However, the value of TyG index combined with thyroid hormones (THs) to affect CAD has not been fully evaluated. Here, we investigated the association between TyG index and THs and further studied the impacts of TyG index and THs on CAD in euthyroid.MethodsSubjects (1,297) with euthyroid who underwent selective coronary angiography (CAG) were enrolled in the present study, including 893 patients with CAD and 404 controls. The association between TyG index and THs were analyzed by linear regression models. Multivariate logistic regression analysis was used to evaluate the interaction of TyG and THs with the risk of CAD. According to the cutoff value of free triiodothyronine (FT3), free thyroxine (FT4), thyroid-stimulating hormone (TSH), and TyG index, the patients were respectively separated into four groups: low TyG/FT3 (low or high), high TyG/FT3 (low or high), low TyG/FT4 (low or high), high TyG/FT4 (low or high), low TyG/TSH (low or high), high TyG/TSH (low or high).ResultsThe baseline analysis showed that FT4 level differs among the three groups according to the tertile of the TyG index. Multiple linear regression analysis revealed decreased serum FT3 level and serum FT4 level as an independent risk factor for elevated TyG index. After adjusting for confounding variables, multiple logistic regression analysis showed that patients with lower TyG index and higher FT3 level had an important protective effect on CAD when considering patients with lower TyG index and FT3 level as reference(OR = 0.536, 95% CI: 0.369–0.778, P = 0.001). Patients with higher TyG index and FT4 level (lower or higher) had a significantly increased risk of CAD (OR 1.656, 95% CI: 1.117–2.455; OR = 1.920, 95% CI: 1.279–2.848, respectively). The area under the curve for the combined diagnosis of CAD by TyG index and FT3 level is 0.615.ConclusionsThese findings suggest that TyG is independently negatively correlated with FT3 or FT4 in euthyroid. In addition, there was a significant interaction between TyG index and THs on the risk of CAD.

ObjectiveTo study whether free triiodothyronine (FT3) within normal range has effects on the presence and severity of coronary artery disease (CAD) in different gender and age groups.MethodsA total of 4206 euthyroid patients were consecutively enrolled and divided into CAD group (n = 3306) and non-CAD group (n = 900). All patients underwent coronary angiography (CAG). Gensini score (GS) was used to determine the severity of coronary artery stenosis. Severe CAD was defined as GS > 32 and mild CAD was defined as GS ≤ 32. Logistic regression analysis and linear regression analysis were conducted to determine the association of FT3 with CAD in patients with different gender and ages.ResultsConcentration of FT3 was lower in patients with CAD than that in angiography-normal control group (P < 0.05). In addition, concentration of FT3 was lower in severe CAD than that in mild CAD. After adjusting for traditional cardiovascular risk factors and potential confounders, FT3 was negatively correlated with the presence of CAD, but not in the old patients (> 65 years old). Multivariable linear regression analysis showed that FT3 was negatively associated with GS in male and young patients with stable CAD, but not in the old patients.ConclusionsLow FT3 within normal range was negatively associated with the presence and severity of CAD in young patients, but not in the old ones. Further studies are needed to confirm our findings.

Background and aimsIt has been confirmed that remnant-like particle cholesterol (RLP-C) mediates the progression of coronary artery disease (CAD). Currently there is limited information on RLP-C in menopausal women. With the special status of diabetes mellitus (DM) combined with the special body changes of the menopausal women, the RLP-C is particularly important when studying the changes that occurred in response to CAD and its associated risk factors. This study discussed whether RLP-C could be an independent risk factor for menopausal women with CAD and DM.MethodsThe cohort consisted of 4753 menopausal women who had undergone coronary angiography. Subjects were separated into CAD and non-CAD groups, and univariate and multivariate logistic regression analysis of CAD risk factors were performed. All patients with a history of DM were divided into DM subgroups. Then, the univariate and multivariate logistic regression analysis of the risk factors of CAD and the comparison among age groups in the DM subgroup were performed. After age stratification of the DM group, the Kruskal-Wallis test was used to analyze the differences of various lipid indexes among age groups.ResultsThe multivariate logistic regression showed that RLP-C was an independent risk factor for CAD in menopausal women (OR 1.232, 95%CI 1.070–1.419). In the DM subgroup, it was also found that RLP-C was an independent risk factor for CAD (OR 1.366, 95%CI 1.043–1.791). Kruskal-Wallis test analysis found that RLP-C had no significant difference among three groups (P > 0.05).ConclusionsRLP-C was proved to be an independent risk factor for menopausal women with CAD and DM.

Overt hypothyroidism(HO) defined as high Thyroid Stimulating Hormone (TSH) lev­els with low levels of free thyroxine (FT4) and / or free triiodothyronine (FT3). Hypothyroidism is associated with an increased risk for atherosclerotic cardiovascular disease. Serum Homocysteine (Hcy) is a independent risk factor for atherosclerosis and cardiovascular diseases. Elevated plasma homocysteine levels have been reported in overt hypothyroidism. : To study levels of Hcy in relation to TSH, FT4 and FT3 levels in overt hypothyroid patients compared to control groups and correlation between Hcy and thyroid hormones. This study included 50 female overt hypothyroid cases with age group between 18-50 years and 50 healthy females controls with same age group. Serum homocysteine was estimated by Homocysteine Enzyme Assay in Cobas Integra 400 plus. TSH, FT4 &amp; FT3 estimated by CLIA method using Beckman coulter Access 2. Parameters of cases and controls are compared using unpaired ‘t’ test and the association between parameters is assessed by using Pearson’s correlation. There is a significant increase in Serum Hcy levels 19.24 ± 7.15 μmol/L and TSH levels 30.91 ± 10.21 µIU/ml respectively (p value &amp;#60;0.0001) and significant decrease in FT4 and FT3 levels (p &amp;#60;0.0001). Hcy was positively correlated with TSH and negatively correlated with FT4 and FT3. Thus, from our study we can conclude that serum Hcy levels can be used as a marker, which points towards the possible risk factor for atherosclerosis and cardiovascular diseases in Overt hypothyroid patients.

Clinical Characteristics and Risk Factors of Coronary Artery Disease in Patients with Hypertension and Persistent Atrial Fibrillation.

Thyroid bone disease

BackgroundRemnant cholesterol (RC) represents a low-cost and readily measured lipid index that contributes significantly to residual cardiovascular disease risk. The triglyceride-glucose (TyG) index exhibits a significant correlation with cardiovascular disease occurrence. However, RC and the TyG index have rarely been examined for their potentials in predicting coronary artery disease (CAD). Accordingly, the study was designed to validate the correlations of these two biomarkers with CAD and to compare the forecasted values of these two biomarkers for newly diagnosed CAD.MethodsTotally 570 subjects firstly administered coronary angiography were enrolled, including 431 newly diagnosed CAD cases and 139 individuals without CAD. The individuals were classified into two groups according to CAD diagnosis. RC was derived as total cholesterol content (mmol/L) – (high density lipoprotein cholesterol content + low density lipoprotein cholesterol content; both in mmol/L). The TyG index was determined as ln (fasting triglyceride level [mg/dL] × fasting plasma glucose level [mg/dL])/2.ResultsBaseline feature analysis revealed significant differences in RC and the TyG index between the CAD and non-CAD groups (both P < 0.001). RC and the TyG index were independent risk factors for CAD in accordance with logistic regression analysis (both P < 0.05). Moreover, spearman correlation analysis elucidated CAD had a more remarkable correlation with the TyG index compared with RC (both P < 0.001). Furthermore, according to receiver operating characteristic curve analysis, the TyG index was better than RC in predicting CAD.ConclusionsThe TyG index and RC have significant associations with CAD. Compared with RC, the TyG index possesses a closer correlation with CAD and a higher predictive value for CAD.

BackgroundThe aim of this study was to investigate the associations of two nontraditional glycemic markers, glycated albumin (GA) and 1,5-anhydroglucitol (1,5-AG), as well as glycated hemoglobin A1c (HbA1c) with coronary artery disease (CAD).MethodsIn total, 272 subjects (178 men and 94 postmenopausal women) were enrolled in this study. All of them underwent coronary angiography which was used to diagnose CAD. The severity of coronary artery stenosis was assessed by the coronary stenosis index (CSI). GA and 1,5-AG were assayed using the enzymatic method, and HbA1c was detected by high-pressure liquid chromatography.ResultsThe HbA1c and GA levels were significantly higher in CAD group than those in non-CAD group (both P < 0.01). While the 1,5-AG level was significantly lower in CAD group than that in non-CAD group (P < 0.05). After adjustment for traditional risk factors of CAD, HbA1c, 1,5-AG, and GA, multivariate logistic regression analysis showed that GA was an independent risk factor for CAD (odds ratio = 1.143, 95% confidence interval: 1.048-1.247, P = 0.002). With CSI as a dependent variable, multiple stepwise regression analysis demonstrated an independent positive correlation between GA and CSI (standardized β = 0.184, P = 0.003), beyond gender, age, and lipid-lowering therapy, after adjustment for traditional risk factors of CAD, HbA1c, 1,5-AG, and GA.ConclusionsGA was more closely correlated with CAD than HbA1c and 1,5-AG in a Chinese population with high risk of CAD.

Stress test electrocardiogram (ECG) analysis is widely used for coronary artery disease (CAD) diagnosis despite its limited accuracy. Alterations in autonomic modulation of cardiac electrical activity have been reported in CAD patients during acute ischemia. We hypothesized that those alterations could be reflected in changes in ventricular repolarization dynamics during stress testing that could be measured through QT interval variability (QTV). However, QTV is largely dependent on RR interval variability (RRV), which might hinder intrinsic ventricular repolarization dynamics. In this study, we investigated whether different markers accounting for low-frequency (LF) oscillations of QTV unrelated to RRV during stress testing could be used to separate patients with and without CAD. Power spectral density of QTV unrelated to RRV was obtained based on time-frequency coherence estimation. Instantaneous LF power of QTV and QTV unrelated to RRV were obtained. LF power of QTV unrelated to RRV normalized by LF power of QTV was also studied. Stress test ECG of 100 patients were analysed. Patients referred to coronary angiography were classified into non-CAD or CAD group. LF oscillations in QTV did not show significant differences between CAD and non-CAD groups. However, LF oscillations in QTV unrelated to RRV were significantly higher in the CAD group as compared with the non-CAD group when measured during the first phases of exercise and last phases of recovery. ROC analysis of these indices revealed area under the curve values ranging from 61 to 73%. Binomial logistic regression analysis revealed LF power of QTV unrelated to RRV, both during the first phase of exercise and last phase of recovery, as independent predictors of CAD. In conclusion, this study highlights the importance of removing the influence of RRV when measuring QTV during stress testing for CAD identification and supports the added value of LF oscillations of QTV unrelated to RRV to diagnose CAD from the first minutes of exercise. This article is part of the theme issue 'Advanced computation in cardiovascular physiology: new challenges and opportunities'.