Impact of ethnicity on cardiac adaptation to exercise

Right ventricular assessment of the adolescent footballer's heart

INTRODUCTION

Athletic training can result in electrical and structural changes of the right ventricle that may mimic phenotypical features of arrhythmogenic right ventricular cardiomyopathy (ARVC), such as T-wave inversion and right heart dilatation. An erroneous interpretation may have consequences ranging from false reassurance in an athlete vulnerable to cardiac arrhythmias, to unnecessary sports restriction in a healthy individual. The primary aim of this study was to define normal RV dimension reference ranges for academy adolescent footballers of different ethnicities. Secondary aims include analysis of potential overlap between this adolescent group with ARVC criteria and comparison with normal adult ranges.

RESULTS

Electrocardiographic (ECG) and echocardiographic data of 1087 academy male footballers aged between 13 and 18 years old (mean age 16.0 ± 0.5 years), attending mandatory cardiac screening were analysed. Ethnicity was categorised as white (n = 826), black (African/Caribbean; n = 166) and mixed-race (one parent white and one parent black; n = 95). Arrhythmogenic right ventricular cardiomyopathy major criteria for T-wave inversion was seen in 3.3% of the cohort. This was more prevalent in black footballers (12%) when compared to mixed race footballers (6.3%) or white footballers (1%), P < 0.05. Up to 59% of the cohort exceeded adult reference ranges for some of the right ventricular parameters, although values were similar to those seen in adult footballers. There were no differences in right ventricular dimensions between ethnicities. In particular, the right ventricular outflow tract diameter would fulfil major criteria for ARVC dimension in 12% of footballers. Overall, 0.2% of the cohort would fulfil diagnosis for 'definite' arrhythmogenic right ventricular cardiomyopathy and 2.2% would fulfil diagnosis for 'borderline' arrhythmogenic right ventricular cardiomyopathy for RV dimensions and ECG changes. This was seen more frequently in black footballers (9.9%) than mixed race footballers (3.9%) or white footballer (0.6%), P < 0.05. Among athletes meeting definite or borderline arrhythmogenic right ventricular cardiomyopathy criteria, no cardiomyopathy was identified after comprehensive clinical assessment, including with cardiac magnetic resonance imaging, exercise testing, ambulatory electrocardiograms and familial evaluation.

CONCLUSION

Right heart sizes in excess of accepted adult ranges occurred in as many as one in two adolescent footballers. Structural adaptations in conjunction with anterior T-wave inversion may raise concern for ARVC, highlighting the need for evaluation in expert settings.

Exercise and cardiovascular health: A state-of-the-art review

Cardiovascular (CV) disease (CVD) is the leading cause of global morbidity and mortality, and low levels of physical activity (PA) is a leading independent predictor of poor CV health and associated with an increased prevalence of risk factors that predispose to CVD development. In this review, we evaluate the benefits of exercise on CV health. We discuss the CV adaptations to exercise, focusing on the physiological changes in the heart and vasculature. We review the impact and benefits of exercise on specific CV prevention, including type II diabetes, hypertension, hyperlipidemia, coronary artery disease, and heart failure, in addition to CVD-related and all-cause mortality. Lastly, we evaluate the current PA guidelines and various modes of exercise, assessing the current literature for the effective regimens of PA that improve CVD outcomes.

Cardiac structure and function of elite volleyball players across different playing positions

BACKGROUND

Volleyball is a popular Olympic sport but has been little studied. Volleyball players have very distinct roles based on their playing positions. The present study aimed to investigate and compare cardiac functions and structure in elite volleyball players across different playing positions.

METHODS

Left ventricular structure and function were measured using echocardiography in 60 male professional volleyball players (30.6±3.6 years) across five playing positions including libero, opposite players, outside hitters, middle blockers, and setters.

RESULTS

Significant differences in most echocardiographic variables were observed among different playing positions, including left ventricular (LV) internal dimension, posterior wall thickness, intact ventricular septum, stroke volume, cardiac output, end-diastolic volume, ejection fraction, and fractional shortening (all P<0.01). End-systolic volume was not different among positions (P=0.167). The opposite players demonstrated greater LV dimension and thickness as well as systolic function than players in other positions (P<0.05). Stroke volume in the setters was significantly lower than those of the opposite players and outside hitters (P<0.05). Regression analysis showed that the playing position independently predicted most of the echocardiographic variables (P<0.05).

CONCLUSIONS

LV adaptations in volleyball players vary widely according to their playing positions. The opposite players had the most pronounced LV adaptations compared with player in other positions.

Sex-specific cardiometabolic risk markers of left ventricular mass in physically active young adults: the CHIEF heart study

Greater physical fitness may lead to greater left ventricular mass (LVM) and reduce the effect of cardiometabolic risk factors on LVM. However, the cardiometabolic biomarkers associations for LVM have not been clarified in physically active young adults. This study included 2019 men and 253 women, aged 18-43 years, from the military in Taiwan. All participants underwent anthropometric and blood metabolic markers measurements, and completed a 3000-m run test for assessing fitness. LVM was calculated on the basis of an echocardiography. Multiple linear regression was used to determine the sex-specific associations between cardiometabolic risk markers and LVM indexed for the body height (g/m^2.7). In men, age, systolic blood pressure (SBP), 3000-m running time, serum triglycerides, serum uric acid and waist circumference (WC) were correlated with LVM index (β = 0.07, 0.10, - 0.01, 0.01, 0.24 and 0.24, respectively; all p-values < 0.05). The correlations were not significant for fasting plasma glucose, total cholesterol and high-density lipoprotein cholesterol (HDL-C). In women, SBP, HDL-C and WC were correlated with LVM index in the univariate analysis (β = 0.07, - 0.05 and 0.32, respectively; all p-values < 0.05), whereas the correlation was only significant for WC in the multiple linear regression analysis (β = 0.20; p-value < 0.001). In physically active adults, the associations of cardiometabolic risk markers with LVM might vary by sex. Better endurance exercise performance associated with greater LVM was noted only in men, while greater WC was the only metabolic risk marker for greater LVM in both men and women.

Flexible Electronics and Devices as Human-Machine Interfaces for Medical Robotics

Medical robots are invaluable players in non-pharmaceutical treatment of disabilities. Particularly, using prosthetic and rehabilitation devices with human-machine interfaces can greatly improve the quality of life for impaired patients. In recent years, flexible electronic interfaces and soft robotics have attracted tremendous attention in this field due to their high biocompatibility, functionality, conformability, and low-cost. Flexible human-machine interfaces on soft robotics will make a promising alternative to conventional rigid devices, which can potentially revolutionize the paradigm and future direction of medical robotics in terms of rehabilitation feedback and user experience. In this review, the fundamental components of the materials, structures, and mechanisms in flexible human-machine interfaces are summarized by recent and renowned applications in five primary areas: physical and chemical sensing, physiological recording, information processing and communication, soft robotic actuation, and feedback stimulation. This review further concludes by discussing the outlook and current challenges of these technologies as a human-machine interface in medical robotics.

Electrocardiographic and Echocardiographic Insights From a Prospective Registry of Asian Elite Athletes

Background: Asian representation in sport is increasing, yet there remains a lack of reference values for the Asian athlete's heart. Consequently, current guidelines for cardiovascular screening recommend using Caucasian athletes' norms to evaluate Asian athletes. This study aims to outline electrocardiographic and echocardiographic characteristics of the Asian athlete's heart using a Singaporean prospective registry of Southeast (SE) Asian athletes.

Methods and Results: One hundred and fifty elite athletes, mean age of 26.1 ± 5.7 years (50% males, 88% Chinese), were evaluated using a questionnaire, 12-lead electrocardiogram (ECG) and transthoracic echocardiogram. All ECGs were analyzed using the 2017 International Recommendations. Echocardiographic data were presented by gender and sporting discipline. The prevalence of abnormal ECGs among SE Asian athletes was 6.7%—higher than reported figures for Caucasian athletes. The abnormal ECGs comprised mainly anterior T wave inversions (ATWI) beyond lead V2, predominantly in female athletes from mixed/endurance sport (9.3% prevalence amongst females). None had echocardiographic structural abnormalities. Male athletes had reduced global longitudinal strain compared to females (−18.7 ± 1.6 vs. −20.7 ± 2.1%, p < 0.001). Overall, SE Asian athletes had smaller left ventricular cavity sizes and wall thickness compared to non-Asian athletes.

Conclusion: SE Asian athletes have higher abnormal ECG rates compared to Caucasian athletes, and also demonstrate structural differences that should be accounted for when interpreting their echocardiograms compared to athletes of other ethnicities.

Data-driven clustering supports adaptive remodeling of athlete's hearts: An echocardiographic study from the Taipei Summer Universiade

BACKGROUND/PURPOSE

Sport-specific adaptations of athlete's hearts are still under investigation. This study sought to 1) identify athlete groups with similar characteristics by clustering echocardiographic data; 2) externally validate the data-driven clusters with sport classifications of various dynamic or static loads to support the conventional hypothesis-driven approach in delineating the athlete's heart.

METHODS

Anthropometric, echocardiographic and electrocardiographic assessments were collected during the 2017 Summer Universiade in Taiwan. Besides standard echocardiography and strain measurements, ventricular-arterial coupling (VAC) was assessed by the ratio of effective arterial elastance (Ea) to left ventricular end-systolic elastance (Ees) as calculated by a modified single-beat algorithm.

RESULTS

We grouped 598 elite athletes (348 male, age 23 ± 2.5 years, across 24 disciplines) using Mitchell's classification. The hypothesis-driven analysis showed dynamic training-related adaptations in heart rate and morphology, including ventricular size, mass, and stroke volume. In comparison, the unsupervised approach found two clusters for each sex. Male athletes participating in high dynamic-load exercises had larger chambers, supranormal diastolic functions, depressed Ees, lower Ea and preserved optimal VAC implicating the resting status of a reservoir-rich pump, which affirmed sport-specific adaptation. The female athletes could be clustered with more noticeable functional alterations, such as depressed biventricular strain. However, the imbalanced number between clusters impeded the validation of load-related remodeling.

CONCLUSION

Hierarchical clustering could analyze complicated multiparametric interactions among numerous echocardiography-derived phenotypes to discern the adaptive propensity of the athlete's heart. The endorsement or generation of hypotheses by a data-driven approach can be applied to various domains.

Athlete's Heart in Asian Military Males: The CHIEF Heart Study

Background: Elite athlete's heart is characterized by a greater left ventricular mass indexed by body surface area (LVMI) and diastolic function; however previous studies are mainly conducted in non-Asian athletes compared to sedentary controls.

Methods: This study included 1,388 male adults, aged 18–34 years, enrolled in the same unified 6-month physical training program in Taiwan. During the midterm exams of 2020, all trainees completed a 3-km run (endurance) test, and 577 were randomly selected to attend a 2-min push-up (muscular strength) test. Elite athletes were defined as the performance of each exercise falling one standard deviation above the mean (16%). Cardiac structure and function were measured by echocardiography and compared between elite and non-elite athletes. Multiple logistic regression analysis was used to determine the independent predictors of elite athlete status at each exercise modality.

Results: As compared to non-elite controls, elite endurance athletes had greater LVMI (84.4 ± 13.6 vs. 80.5 ± 12.9 g/m², p < 0.001) and lateral mitral E'/A' ratio (2.37 ± 0.73 vs. 2.22 ± 0.76, p < 0.01) with lower late diastolic A' (7.77 ± 2.16 vs. 8.30 ± 3.69 cm/s, p = 0.03). Elite strength athletes had greater LVMI (81.8 ± 11.4 vs. 77.5 ± 12.1, p = 0.004) and lateral mitral E'/A' ratio (2.36 ± 0.70 vs. 2.11 ± 0.71, p < 0.01) with a greater early diastolic E' (19.30 ± 4.06 vs. 18.18 ± 4.05 cm/s, p = 0.02). Greater LVMI and lower heart rate were independent predictors of elite endurance athletes [odds ratio (OR) and 95% confidence intervals: 1.03 (1.02, 1.04) and 0.96 (0.95, 0.98), respectively]. Greater LVMI, lateral mitral E'/A' ratio and right ventricular systolic pressure were independent predictors of elite strength athletes [OR: 1.03 (1.01, 1.05), 1.50 (1.06, 2.12), and 1.12 (1.05, 1.19), respectively].

Conclusions: Cardiac structural and functional characteristics differ between endurance and strength elite athletes. While greater LVMI predicts elite status in both groups of Asian athletes, consistent with findings from Western elite athletes, greater diastolic function, and right ventricular systolic pressure characterize strength elite athletes, while lower heart rate at rest predicts endurance elite athletic status.

Exercise-Induced Cardiovascular Adaptations and Approach to Exercise and Cardiovascular Disease: JACC State-of-the-Art Review

The role of the sports cardiologist has evolved into an essential component of the medical care of athletes. In addition to the improvement in health outcomes caused by reductions in cardiovascular risk, exercise results in adaptations in cardiovascular structure and function, termed exercise-induced cardiac remodeling. As diagnostic modalities have evolved over the last century, we have learned much about the healthy athletic adaptation that occurs with exercise. Sports cardiologists care for those with known or previously unknown cardiovascular conditions, distinguish findings on testing as physiological adaptation or pathological changes, and provide evidence-based and "best judgment" assessment of the risks of sports participation. We review the effects of exercise on the heart, the approach to common clinical scenarios in sports cardiology, and the importance of a patient/athlete-centered, shared decision-making approach in the care provided to athletes.

Coronavirus Disease 2019: Cardiac Complications and Considerations for Returning to Sports Participation

Coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus 2. While the majority of symptoms and morbidity relate to the lung, cardiac complications have been well reported and confer increased mortality. Many countries in Europe have passed the peak of the pandemic and adaptations are being made as we progress towards a 'new normal'. As part of this, governments have been planning strategies for the return of elite sports. This article summarises the potential implications of COVID-19 for athletes returning to sport, including common cardiac complications of the disease; consensus recommendations for the return to sport after having COVID-19; and international recommendations for the management of cardiac pathology that may occur as a result of COVID-19. The authors also examine the potential overlap of pathology with physiological change seen in athletes' hearts.

Screening of Potential Cardiac Involvement in Competitive Athletes Recovering From COVID-19: An Expert Consensus Statement

As our understanding of the complications of coronavirus disease-2019 (COVID-19) evolve, subclinical cardiac pathology such as myocarditis, pericarditis, and right ventricular dysfunction in the absence of significant clinical symptoms represents a concern. The potential implications of these findings in athletes are significant given the concern that exercise, during the acute phase of viral myocarditis, may exacerbate myocardial injury and precipitate malignant ventricular arrhythmias. Such concerns have led to the development and publication of expert consensus documents aimed at providing guidance for the evaluation of athletes after contracting COVID-19 in order to permit safe return to play. Cardiac imaging is at the center of these evaluations. This review seeks to evaluate the current evidence regarding COVID-19-associated cardiovascular disease and how multimodality imaging may be useful in the screening and clinical evaluation of athletes with suspected cardiovascular complications of infection. Guidance is provided with diagnostic "red flags" that raise the suspicion of pathology. Specific emphasis is placed on the unique challenges posed in distinguishing athletic cardiac remodeling from subclinical cardiac disease. The strengths and limitations of different imaging modalities are discussed and an approach to return to play decision making for athletes post-COVID-19, as informed by multimodality imaging, is provided.

Effect of race on longitudinal central hemodynamics in pregnancy

OBJECTIVE

To compare central hemodynamics between white, black and Asian women in pregnancy.

METHODS

This was a prospective, longitudinal study of maternal central hemodynamics in white, black and Asian women with a singleton pregnancy, assessed using a bioreactance method at 11 + 0 to 13 + 6, 19 + 0 to 24 + 0, 30 + 0 to 34 + 0 and 35 + 0 to 37 + 0 weeks' gestation. At each visit, cardiac output (CO), stroke volume (SV), heart rate (HR), peripheral vascular resistance (PVR) and mean arterial pressure were recorded. Multilevel linear mixed-effects analysis was performed to compare the repeated measures of the cardiac variables between white, black and Asian women, controlling for maternal characteristics, medical history and medication use.

RESULTS

The study population included 1165 white, 247 black and 116 Asian women. CO increased with gestational age to a peak at 32 weeks and then decreased; the highest CO was observed in white women and the lowest in Asian women. SV initially increased after the first visit but subsequently declined with gestational age in white women, decreased with gestational age in black women and remained static in Asian women. In all three study groups, HR increased with gestational age until 32 weeks and then remained constant; HR was highest in black women and lowest in white women. PVR showed a reversed pattern to that of CO; the highest values were in Asian women and the lowest in white women. The least favorable hemodynamic profile, which was observed in black and Asian women, was reflected in higher rates of a small-for-gestational-age infant.

CONCLUSIONS

There are race-specific differences in maternal cardiac adaptation to pregnancy. White women have the most favorable cardiac adaptation by increasing SV and HR, achieving the highest CO and lowest PVR. In contrast, black and Asian women have lower CO and higher PVR than do white women, with CO increasing through a rise in HR due to declining or static SV. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Evaluation of left ventricular remodelling in young Afro-Caribbean athletes

Background

Cardiac adaptation to intense physical training is determined by many factors including age, gender, body size, load training and ethnicity. Despite the wide availability of ECG analysis, with a higher presence of abnormalities in different races, echocardiographic studies on young Afro-Caribean (AA) and Caucasian athletes (CA) are lacking in literature. We aimed to assess the effect in the secondary LV remodelling of load training in young AA players compared to matched CA players.

Method

Seventy-seven AA and 53 CA matched soccer players (mean age 17.35 ± 0.50 and 18.25 ± 0.77 y) were enrolled. They were evaluated with echocardiography. A subgroup of 30 AA and 27 CA were followed up for a period of 4 years. The myocardial contractile function was evaluated by speckle-tracking echocardiographic global longitudinal strain (GLS).

Results

No significant differences were found in weight and height and in blood pressure response to maximal ergometer test in either group. In AA a higher level of LV remodelling, consisting in higher LV wall thickness, higher interventricular septum (IVS) and posterior wall (PW) thickness were found (IVS: 10.04 ± 0.14 and 9.35 ± 0.10 in AA and CA respectively, p < 0.001. PW: 9.70 ± 0.20 and 9.19 ± 0.10 mm in AA and CA respectively, p < 0.05). Strain data showed no significant differences between the two groups (22.35 ± 0.48 and 23.38 ± 0.69 in AA (n = 27) and CA (n = 25), respectively). At the beginning of the follow-up study AA showed a significantly higher left ventricular remodelling (IVS = 9.29 ± 0.3 and 8.53 ± 0.12 mm in AA and CA respectively, p < 0.002. PW = 9.01 ± 0.2 and 8.40 ± 0.20 in AA and CA respectively, p = 0.1). During the next four years of follow-up we observed a regular parallel increase in LV wall thickness and chamber diameters in both groups, proportionally to the increase in body size and LV mass. (IVS = 10.52 ± 0.17 and 9.03 ± 0.22 mm in AA and CA respectively, p < 0.001. PW: 10.06 ± 0.17 and 8.26 ± 0.19 mm in AA and CA respectively, p < 0.001).

Conclusion

The study shows that the ventricular remodelling observed in AA appears to be a specific phenotype already present in pre-adolescence. These data also suggest that genetic/ethnic factors play a central role in left ventricular remodelling during the first years of life in elite athletes.

Left Ventricular Hypertrophy in Athletes: Differentiating Physiology From Pathology

PURPOSE OF REVIEW

The changes that occur in athlete's heart are influenced by a number of factors including age, gender, ethnicity and the type of cardiovascular training. It is therefore important that the clinician is able to integrate all of these factors when assessing athletes to be able to guide investigations appropriately and to distinguish pathology from physiology. This review discusses the potential diagnostic conundrums when trying to differentiate physiological left ventricular hypertrophy from pathological hypertrophic cardiomyopathy in athletes. The mechanism of physiological and pathological hypertrophy is discussed together with history, clinical and investigational findings that can help to identify pathology.

RECENT FINDINGS

Athletes with hypertrophic cardiomyopathy are more likely to have non-concentric left ventricular hypertrophy (LVH), an elevated relative wall thickness, lateral ECG changes and a smaller LV cavity than athletes with physiological LVH. Certain diastolic echocardiographic parameters when used as part of an algorithm (e'; E/E'; E/A) can help to distinguish physiology from pathology, and there is evidence that assessment of global longitudinal strain during exercise echocardiography may be of use in the future. Cardiac MRI is an important imaging modality that can have an additive effect over echocardiography in the diagnosis of cardiomyopathy. Late gadolinium enhancement is a recognised advantage for cardiac magnetic resonance to allow detection of fibrosis in hypertrophic cardiomyopathy. T1 mapping and extracellular volume quantification may be a tool for the future to help distinguish athlete's heart from HCM. Cardiac adaptation to exercise and training in athletes, the athlete's heart causes electrophysiological and geometric changes that may mimic mild phenotypes of a pathological cardiomyopathy. This review article summarises a systematic approach to the assessment of left ventricular hypertrophy in athletes and describes pertinent clinical and investigation findings that can help to differentiate physiology from pathology.

Dissecting the pathophysiology of immune thrombotic thrombocytopenic purpura: interplay between genes and environmental triggers

Although outstanding progress has been made in understanding the pathophysiology of thrombotic thrombocytopenic purpura (TTP), knowledge of the immunopathogenesis of the disease is only at an early stage. Anti-ADAMTS13 auto-antibodies were shown to block proteolysis of von Willebrand factor and/or induce ADAMTS13 clearance from the circulation. However, it still remains to identify which immune cells are involved in the production of anti-ADAMTS13 autoantibodies, and therefore account for the remarkable efficacy of the B-cell depleting agents in this disease. The mechanisms leading to the loss of tolerance of the immune system towards ADAMTS13 involve the predisposing genetic factors of the human leukocyte antigen class II locus DRB1*11 and DQB1*03 alleles as well as the protective allele DRB1*04, and modifying factors such as ethnicity, sex and obesity. Future studies have to identify why these identified genetic risk factors are also frequently to be found in the healthy population although the incidence of immune-mediated thrombotic thrombocytopenic purpura (iTTP) is extremely low. Moreover, the development of recombinant ADAMTS13 opens a new therapeutic era in the field. Interactions of recombinant ADAMTS13 with the immune system of iTTP patients will require intensive investigation, especially for its potential immunogenicity. Better understanding of iTTP immunopathogenesis should, therefore, provide a basis for the development of novel therapeutic approaches to restore immune tolerance towards ADAMTS13 and thereby better prevent refractoriness and relapses in patients with iTTP. In this review, we address these issues and the related challenges in this field.

Using the 12-Lead Electrocardiogram in the Care of Athletic Patients

This article summarizes the role of the 12-lead electrocardiogram (ECG) for the clinical care of athletes, with particular reference to the influence of age, gender, ethnicity, and type of sport on the appearance of the ECG, and its role in differentiating physiologic exercise-related changes from pathologic conditions implicated in sudden cardiac death (SCD). The article also explores the potential role of the ECG in detecting athletes at risk of SCD. In addition, the article reviews the evolution of ECG interpretation criteria and emphasizes the limitations of the ECG as well as the potential for future research.

Gender differences in the electrocardiogram screening of athletes

OBJECTIVES

Gender-related differences are frequently used in medicine. Electrocardiograms are also subject to such differences. This study evaluated gender differences in ECG parameters of young athletes, discussing the possible implications of these differences for ECG criteria used in the cardiovascular screening of young athletes.

DESIGN

Observational cross-sectional study.

METHODS

In 2013 and 2014 all the ECGs from the cardiovascular screenings performed at University Sports Medical Centre in Groningen of the student athletes who wanted to participate in a college sports program were collected. The ECG characteristics were scored using computer-based measurements and the Seattle ECG criteria.

RESULTS

The study population included 1436 athletes, of which 72% were male. Male athletes were older (19.3 years vs. 18.6 years), participated in sports more frequently (4.0/week vs. 3.8/week) and spent more hours per week practising sports (6.4h/week vs. 5.8h/week) than female athletes. Male athletes had significantly higher PR intervals (149ms vs. 141ms), lead voltages and QRS duration (98ms vs. 88ms). Female athletes had significantly higher resting heart rates (69/min vs. 64/min) and QTc intervals (407ms vs. 400ms). Male athletes also had significantly higher amounts of sinus bradycardia (38.3% vs. 23.0%), incomplete RBBB (15.0% vs. 3.7%), early repolarisation (4.5% vs. 1.0%) and isolated QRS voltage criteria for LVH (26.3% vs. 4.6%). All P-values were ≤0.001.

CONCLUSIONS

ECGs of young athletes demonstrate gender-related differences. These differences could be considered in their cardiovascular screening. For the Seattle ECG criteria we advise additional research into the clinical implications of using gender-based cut-off values for the QRS duration in the intraventricular conduction delay criterion.

Identifying postmenopausal women at risk for cognitive decline within a healthy cohort using a panel of clinical metabolic indicators: potential for detecting an at-Alzheimer's risk metabolic phenotype

Detecting at-risk individuals within a healthy population is critical for preventing or delaying Alzheimer's disease. Systems biology integration of brain and body metabolism enables peripheral metabolic biomarkers to serve as reporters of brain bioenergetic status. Using clinical metabolic data derived from healthy postmenopausal women in the Early versus Late Intervention Trial with Estradiol (ELITE), we conducted principal components and k-means clustering analyses of 9 biomarkers to define metabolic phenotypes. Metabolic clusters were correlated with cognitive performance and analyzed for change over 5 years. Metabolic biomarkers at baseline generated 3 clusters, representing women with healthy, high blood pressure, and poor metabolic phenotypes. Compared with healthy women, poor metabolic women had significantly lower executive, global and memory cognitive performance. Hormone therapy provided metabolic benefit to women in high blood pressure and poor metabolic phenotypes. This panel of well-established clinical peripheral biomarkers represents an initial step toward developing an affordable, rapidly deployable, and clinically relevant strategy to detect an at-risk phenotype of late-onset Alzheimer's disease.