Electrocardiographic changes associated with insulin resistance

Interrelationships among abnormal P-wave axis, metabolic syndrome and its components, and mortality in US adults

BACKGROUND

Metabolic syndrome (MetS) is associated with increased rates of cardiovascular disease and mortality and is linked to abnormal electrocardiogram (ECG) parameters. We aimed to explore the relationships and interactions among MetS and its components, abnormal P-wave axis (aPWA), and mortality rates.

METHODS

We analyzed data from 7526 adult participants with sinus rhythm recruited from the National Health and Nutrition Examination Survey III. MetS was classified based on the NCEP ATP III-2005 definition. aPWA included all P-wave axis outside 0-75°. The National Death Index was utilized to identify survival status. Hazard ratios (HRs) and 95% confidence intervals (CIs) categorized by aPWA, MetS, and their components were analyzed using Cox proportional hazards models to investigate all-cause and cardiovascular mortalities.

RESULTS

Within a median follow-up period of 20.76 years, 4686 deaths were recorded, of which 1414 were attributable to cardiovascular disease. Participants with both MetS and aPWA had higher all-cause (HR: 1.45, 95% CI: 1.29-1.64, interaction P = 0.043) and cardiovascular (HR: 1.36, 95% CI: 1.02-1.79, interaction P-value = 0.058) mortality rates than participants without MetS and with a normal P-wave axis. Participants with the greatest number of MetS components and aPWA had a higher risk of all-cause mortality (HR: 1.70, 95% CI: 1.13-2.55, P = 0.011).

CONCLUSIONS

Individuals with both aPWA and MetS have a higher risk of mortality, and those with a greater number of MetS components and aPWA have a higher risk of all-cause mortality. These findings highlight the significance of integrating ECG characteristics with metabolic health status in clinical assessment.

The epicardial fat thickness is associated with fragmented QRS in patients with newly diagnosed metabolic syndrome

OBJECTIVE

The metabolic syndrome involves both metabolic and cardiovascular risk factors and is associated with cardiovascular mortality. Epicardial fat tissue plays a crucial role in deleterious effects of metabolic syndrome on the heart, including myocardial fibrosis. The fragmented QRS reflects heterogeneous depolarization of the myocardium and occurs as a result of fibrosis. Thus, we aimed to investigate whether there is an association between fragmented QRS and epicardial fat tissue in patients with metabolic syndrome.

METHODS

This study enrolled 140 metabolic syndrome patients, of whom 35 patients with fragmented QRS (+) and 105 patients with fragmented QRS (-). The two groups were compared with respect to clinical, laboratory, electrocardiographic, and echocardiographic indexes.

RESULTS

Fragmented QRS (+) patients had higher waist circumference, red cell distribution width, creatinine, left ventricular end-systolic diameter, left atrium diameter, septal a velocity, QRS duration, and epicardial fat tissue compared with fragmented QRS (-) patients. Waist circumference, red cell distribution width, QRS duration, left ventricular end-systolic diameter, left atrium diameter, septal a velocity, and epicardial fat tissue were significantly associated with the presence of fragmented QRS. The QRS duration and epicardial fat tissue were independently associated with the presence of fragmented QRS on surface electrocardiographic in metabolic syndrome patients.

CONCLUSIONS

Epicardial fat tissue and QRS duration were independently associated with the presence of fragmented QRS. Basic echocardiographic and electrocardiographic parameters might be used for the risk stratification in metabolic syndrome patients.

The association between insulin sensitivity indices, ECG findings and mortality: a 40-year cohort study

Background

Type 2 Diabetes is a major risk factor for cardiovascular (CV) mortality. Insulin resistance can be evaluated non-invasively by insulin sensitivity indices (ISI) such as the Mcauley index (MCAi), which is a function of the fasting insulin and triglycerides. Currently, the association between ISIs and ECG findings and all-cause and CV mortality is still not established in a large scale and heterogeneous population.

Method

In a prospective study of the Israel cohort on Glucose Intolerance, Obesity and Hypertension (GOH) second phase (1979–1982) 1830 men and women were followed until December-2016 for CV-mortality and December-2019 for all-cause mortality. ECGs were recorded and OGTTs performed during baseline. ISIs were categorized into quartiles and evaluated against ECG findings and all-cause and CV-mortality.

Results

Mean age at baseline was 52.0 ± 8.1 years, and 75 (15.2%) and 47 (25.3%) participants in the upper quartiles (Q_2-4) and the lower quartile (Q₁) of the MCAi, presented with Ischemic changes on ECG respectively (p = 0.02). Multivariable analysis showed higher odds for ECG ischemic changes, for individuals in Q₁-MCAi (adjusted-OR = 1.7, 95% CI 1.02–2.8), compared with Q_2-4-MCAi, which attenuated when excluding individuals with diabetes (adjusted-OR = 1.6, 95% CI 0.9–2.7, p = 0.09).

Median follow up for all-cause and for cardiovascular mortality was 31 years and 37 years, respectively. Cox proportional-hazards regression showed an increased risk for all-cause mortality for individuals in Q₁-MCAi (HR = 1.2, 95% CI 1.02–1.3) as well as an increased risk for CV-mortality (HR = 1.4, 95%CI 1.1–1.8) compared with Q_2-4-MCAi. Individuals in Q₄-Ln Homeostatic model assessment- Insulin Resistance (HOMA-IR) and Q₁- Quantitative Insulin Sensitivity Check Index (QUICKI) also presented with increased risk for all-cause-mortality (HR = 1.2, 95%CI 1.04–1.4; and HR = 1.2, 95% CI 1.04–1.4, respectively). Other ISIs did not show significant associations with CV-mortality.

Conclusion

Higher insulin-resistance, according to the MCAi, associated with ECG-changes, and with greater risk for all-cause and CV-mortality over a 40-year follow-up. The MCAi may be considered as an early predictive and prognostic biomarker for CV-morbidity and mortality in adults.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-021-01284-9.

The Association of Metabolic Syndrome and Its Components with Electrocardiogram Parameters and Abnormalities Among an Iranian Rural Population: The Fasa PERSIAN Cohort Study

BACKGROUND

Metabolic syndrome (MetS) as a set of cardiac risk factors and its growing prevalence is one of the major concerns in different societies. In this study, we aimed to investigate the relationship between Mets and electrocardiogram (ECG) parameters and abnormalities as indicators for subclinical cardiovascular diseases (CVD).

METHODS

In this sub-analysis study, we used the data from Fasa PERSIAN Cohort Study which includes subjects age 35-70 years. Subjects with available ECG data included in the study (n=7002) and subjects with missing data on MetS components and non-sinus rhythm ECG were excluded (n=44). The MetS definition based on the Adult Treatment Panel (ATP) III guidelines and also a 12-lead ECG was obtained from all participants.

RESULTS

Our study population (n=6958) showed a mean age of 48.60±9.34 years and also 1656 (24.2%) subjects had MetS. Except for P duration, PR interval and S amplitude in men and P amplitude, S amplitude, Sokolow-Lyon Index, and QT interval in women, other ECG parameters differ significantly between subjects with and without Mets (P<0.05). Also among ECG abnormalities, prolonged P duration (≥120ms), QRS duration (≥100ms), and QTc interval (>450ms in male, >470ms in female) had a significant association with MetS in the total population. Waist circumferences (WC) showed the most count of significant relationship with ECG parameters in both genders. In males, WC more than ATP cut-points had significant associations with prolonged P and QRS duration, and also blood pressure (BP) had significant associations with prolonged P and QRS durations and QTc interval. In females, the MetS component except triglyceride had at least a significant relationship with prolonged P and/or QRS duration.

CONCLUSION

MetS and its component especially WC and BP were associated with ECG parameters and abnormalities. These associations with ECG as a marker of subclinical CVD showed the importance of MetS and each component in our population to monitor in the further longitudinal studies.

Body mass index related electrocardiographic findings in healthy young individuals with a normal body mass index

INTRODUCTION

An increased body mass index (BMI) (>25 kg/m²) is associated with a wide range of electrocardiographic changes. However, the association between electrocardiographic changes and BMI in healthy young individuals with a normal BMI (18.5-25 kg/m²) is unknown. The aim of this study was to evaluate the association between BMI and electrocardiographic parameters.

METHODS

Data from 1,290 volunteers aged 18 to 30 years collected at our centre were analysed. Only subjects considered healthy by a physician after review of collected data with a normal BMI and in sinus rhythm were included in the analysis. Subjects with a normal BMI (18.5-25 kg/m²) were divided into BMI quartiles analysis and a backward multivariate regression analysis with a normal BMI as a continuous variable was performed.

RESULTS

Mean age was 22.7 ± 3.0 years, mean BMI was 22.0, and 73.4% were male. There were significant differences between the BMI quartiles in terms of maximum P-wave duration, P-wave balance, total P-wave area in lead V1, PR-interval duration, and heart axis. In the multivariate model maximum P-wave duration (standardised coefficient (SC) = +0.112, P < 0.001), P-wave balance in lead V1 (SC = +0.072, P < 0.001), heart axis (SC = -0.164, P < 0.001), and Sokolow-Lyon voltage (SC = -0.097, P < 0.001) were independently associated with BMI.

CONCLUSION

Increased BMI was related with discrete electrocardiographic alterations including an increased P-wave duration, increased P-wave balance, a leftward shift of the heart axis, and decreased Sokolow-Lyon voltage on a standard twelve lead electrocardiogram in healthy young individuals with a normal BMI.

The Associations between Various Ectopic Visceral Adiposity and Body Surface Electrocardiographic Alterations: Potential Differences between Local and Remote Systemic Effects

Background

The associations between pericardial adiposity and altered atrial conduction had been demonstrated. However, data comparing differential effects of various body sites visceral adiposity on atrial and ventricular electrocardiographic alterations remains largely unknown.

Methods and Results

We assessed both peri-cardial fat (PCF) and peri-aortic visceral adiposity (TAT) using dedicated computed tomography (CT) software (Aquarius 3D Workstation, TeraRecon, San Mateo, CA, USA), with anthropometrics including body mass index (BMI) and biochemical data obtained. We further related PCF and TAT data to standardized 12-leads electrocardiogram (ECG), including P and QRS wave morphologies. Among 3,087 study subjects (mean age, 49.6 years; 28% women), we observed a linear association among greater visceral adiposity burden, leftward deviation of P and QRS axes, longer PR interval and widened QRS duration (all p<0.001). These associations became attenuated after accounting for BMI and baseline clinical co-variates, with greater PCF remained independently associated with prolonged QRS duration (β = 0.91 [95% CI: 0.52, 1.31] per 1-SD increase in PCF, p<0.001). Finally, both PCF and TAT showed incremental value in identifying abnormally high PR interval (>200ms, likelihood-ratio: 33.17 to 41.4 & 39.03 for PCF and TAT) and widened QRS duration (>100ms, likelihood-ratio: 55.67 to 65.4 & 61.94 for PCF and TAT, all X² p<0.05) when superimposed on age and BMI.

Conclusion

We show in our data greater visceral fat burden may have differential associations on several body surface electrocardiographic parameters. Compared to remote adiposity, those surrounding the heart tissue demonstrated greater influences on altered cardiac activation or conduction, indicating a possible local biological effect.

Long-term feeding on powdered food causes hyperglycemia and signs of systemic illness in mice

AIMS

Dietary habits are crucial factors affecting metabolic homeostasis. However, few animal experiments have addressed the effects of long-term feeding with soft food on parameters reflecting systemic health.

MAIN METHODS

Using mice, we compared the effects of short (3 days) and long (17 weeks from weaning) feeding periods between powdered food and normal pellet food on the levels of blood glucose, serum levels of insulin, catecholamines, and corticosterone, blood pressure, and/or social interaction behaviors. In addition, the effects of a human glucagon-like peptide-1 analog, liraglutide (a new drug with protective effects against neuronal and cardiovascular diseases), were compared between the powder and pellet groups.

KEY FINDING

(i) Powdered food, even for such a short period, resulted in a greater glycemic response than pellet food, consistent with powdered food being more easily digested and absorbed. (ii) Long-term feeding on powdered food induced hyperglycemia and related systemic signs of illness, including increases in serum adrenaline, noradrenaline, and corticosterone, higher blood pressures (especially diastolic), and increased social interaction behaviors. (iii) Liraglutide, when administered subcutaneously for the last 2 weeks of the 17-week period of feeding, improved these changes (including those in social interaction behaviors).

SIGNIFICANCE

The hyperglycemia associated with long-term powdered-food feeding may lead to certain systemic illness signs, such as elevations of blood glucose, hypertension, and abnormal behaviors in mice. Mastication of food of adequate hardness may be very important for the maintenance of systemic (physical and mental) health, possibly via reduction in the levels of blood glucose and/or adrenal stress hormones (catecholamines and glucocorticoids).