Impact of general and central adiposity on ventricular-arterial aging in women and men

Association of central obesity with sex hormonebinding globulin: a cross-sectional study of 1166 Chinese men

Background Both sex hormone-binding globulin and central obesity have been found to be associated with metabolic and cardiovascular diseases. However, the direct relation between sex hormone-binding globulin and central obesity has not been demonstrated.

Methodology We performed a cross-sectional study of 1166 male participants from Zunyi, Guizhou, western China, in 2013. Each participant completed a questionnaire and had a brief clinical exam with a fasting blood sample taken. All blood samples underwent standard laboratory testing for sex hormone-binding globulin. Level of serum sex hormone-binding globulin was compared by demographic characteristics, and multiple linear regression was used to evaluate the independent association of variables and sex hormone-binding globulin level.

Results The mean serum level of sex hormone-binding globulin was increased in old-aged men (older than 40 years; mean 44.68±20.58 nmol/L), low diastolic blood pressure (<90mmHg; 43.76±20.50 nmol/L), waist-to-height ratio <0.5 (48.73±20.59 nmol/L), no education (52.36±22.91 nmol/L), farm occupation (43.58±20.60nmol/L), non-alcohol or former user (44.78±20.94 nmol/L) and long-term medication history (44.79±21.50 nmol/L). Factors independently associated with sex hormone binding globulin level on multiple regression were waist-to-height ratio (β=- 11.84 [95% confidence interval -13.96,-9.72]), age(β=12.40 [9.63,15.17]) and diastolic blood pressure (β=-5.07 [-7.44,-2.71]).

Conclusions Central obesity has an independent inverse relation with serum level of sex hormone binding globulin among western Chinese men

Obesity and metabolic features associated with long-term developing diastolic dysfunction in an initially healthy population-based cohort

BACKGROUND

Diastolic dysfunction (DD) is increasingly common. However, its metabolic determinants are poorly known. This study aims to determine which metabolic and inflammatory features predict DD in initially healthy adults.

METHODS

We prospectively analyzed the association between metabolic features and DD in 728 initially healthy adults aged 30-60 from Eastern France enrolled in the STANISLAS population-based cohort. Clinical and biological cardiovascular features were collected at baseline (1994-1995). DD was assessed twenty years later (2011-2016) by echocardiography using current international guidelines. For replication purposes, 1463 subjects from the Malmö Preventive Project cohort were analyzed.

RESULTS

In the STANISLAS cohort, 191 subjects (26.2%) developed DD. In age-sex-adjusted logistic models, significant predictors of DD were body mass index (BMI, odds ratio for 1-standard-deviation increase (OR) 1.28, 95% CI 1.08-1.52), waist circumference (WC, OR 1.48, 95% CI 1.18-1.84), waist-hip ratio (OR 1.53, 95% CI 1.16-2.02), systolic blood pressure (OR 1.19, 95% CI 1.00-1.43) and triglycerides (TG, OR 1.18, 95% CI 1.00-1.40). Subjects with elevated WC (> 80th percentile) and TG (> 50th percentile) had a twofold higher DD risk (age-sex-adjusted odds ratio 2.00, 95% CI 1.20-3.31, P = 0.008), whereas no such interplay was observed for BMI. In the Malmö cohort, BMI was similarly associated with DD; participants with both elevated BMI and TG were at higher DD risk (age-sex-adjusted odds ratio 1.61, 95% CI 1.18-2.20, P = 0.002).

CONCLUSIONS

Subjects with elevated WC and TG may have a higher long-term DD risk. Prevention targeting visceral obesity may help reduce the incidence of DD.

Adiposity, body composition and ventricular-arterial stiffness in the elderly: the Atherosclerosis Risk in Communities Study

AIM

Weight gain appears to accelerate age-related ventricular-arterial stiffening, which has been implicated in the development of heart failure (HF), but it is unclear whether body fat accumulation underpins this association. We evaluated the relationship of adiposity, using measures of body composition, with ventricular-arterial stiffness among the elderly in the community.

METHODS AND RESULTS

Adiposity was accessed through body mass index (BMI), waist circumference, and body fat percentage. We studied the association of these measures with carotid-femoral pulse wave velocity (cfPWV), arterial elastance index (EaI), left ventricular (LV) end-systolic elastance index (EesI) and LV end-diastolic elastance index (EedI) in 5520 community-based, elderly Atherosclerosis Risk in Communities (ARIC) Study participants, who underwent echocardiography between 2011 and 2013. BMI and waist circumference were directly associated with EaI, EedI and EesI even after adjusting for age, sex, race, hypertension, diabetes mellitus, heart rate, prevalent coronary heart disease and HF. After further adjustment for BMI, body fat percentage demonstrated significant independent linear relationships with EaI [standardized beta coefficient (β)=0.17, P<0.001], EesI (β=0.08, P=0.003) and EedI (β=0.20, P<0.001), and significant non-linear relationships with cfPWV (P=0.033).

CONCLUSION

In this biracial community-based cohort, increased adiposity was associated with increased ventricular-arterial stiffness among the elderly and suggests a potential mechanism by which obesity might contribute to the development of HF.

Heart failure with preserved ejection fraction: controversies, challenges and future directions

Heart failure with preserved ejection fraction (HFpEF) comprises almost half of the population burden of HF. Because HFpEF likely includes a range of cardiac and non-cardiac abnormalities, typically in elderly patients, obtaining an accurate diagnosis may be challenging, not least due to the existence of multiple HFpEF mimics and a newly identified subset of patients with HFpEF and normal plasma natriuretic peptide concentrations. The lack of effective treatment for these patients represents a major unmet clinical need. Heterogeneity within the patient population has triggered debate over the aetiology and pathophysiology of HFpEF, and the neutrality of randomised clinical trials suggests that we do not fully understand the syndrome(s). Dysregulated nitric oxide-cyclic guanosine monophosphate-protein kinase G signalling, driven by comorbidities and ageing, may be the fundamental abnormality in HFpEF, resulting in a systemic inflammatory state and microvascular endothelial dysfunction. Novel informatics platforms are also being used to classify HFpEF into subphenotypes, based on statistically clustered clinical and biological characteristics: whether such subclassification will lead to more targeted therapies remains to be seen. In this review, we summarise current concepts and controversies, and highlight the diagnostic and therapeutic challenges in clinical practice. Novel treatments and disease management strategies are discussed, and the large gaps in our knowledge identified.

Obesity and heart failure with preserved ejection fraction: A growing problem

Heart Failure with Preserved Ejection Fraction (HFpEF) is increasing in prevalence due to the aging of the United States population as well as the current obesity epidemic. While obesity is very common in patients with HFpEF, obesity may represent a specific phenotype of HFpEF characterized by unique hemodynamics and structural abnormalities. Obesity induces a systemic inflammatory response that may contribute to myocardial fibrosis and endothelial dysfunction. The most obese patients continue to be excluded from HFpEF clinical trials, and thus ongoing research is needed to determine the role of pharmacologic and interventional approaches in this growing population.

Arterial Stiffening With Exercise in Patients With Heart Failure and Preserved Ejection Fraction

BACKGROUND

Aortic stiffening and reduced nitric oxide (NO) availability may contribute to the pathophysiology of heart failure with preserved ejection fraction (HFpEF).

OBJECTIVES

This study compared indices of arterial stiffness at rest and during exercise in subjects with HFpEF and hypertensive control subjects to examine their relationships to cardiac hemodynamics and determine whether exertional arterial stiffening can be mitigated by inorganic nitrite.

METHODS

A total of 22 hypertensive control subjects and 98 HFpEF subjects underwent hemodynamic exercise testing with simultaneous expired gas analysis to measure oxygen consumption. Invasively measured radial artery pressure waveforms were converted to central aortic waveforms by transfer function to assess integrated measures of pulsatile aortic load, including arterial compliance, resistance, elastance, and wave reflection.

RESULTS

Arterial load and wave reflections in HFpEF were similar to those in control subjects at rest. During submaximal exercise, HFpEF subjects displayed reduced total arterial compliance and higher effective arterial elastance despite similar mean arterial pressures in control subjects. This was directly correlated with higher ventricular filling pressures and depressed cardiac output reserve (both p < 0.0001). With peak exercise, increased wave reflections, impaired compliance, and increased resistance and elastance were observed in subjects with HFpEF. A subset of HFpEF subjects (n = 52) received sodium nitrite or placebo therapy in a 1:1 double-blind, randomized fashion. Compared to placebo, nitrite decreased aortic wave reflections at rest and improved arterial compliance and elastance and central hemodynamics during exercise.

CONCLUSIONS

Abnormal pulsatile aortic loading during exercise occurs in HFpEF independent of hypertension and is correlated with classical hemodynamic derangements that develop with stress. Inorganic nitrite mitigates arterial stiffening with exercise and improves hemodynamics, indicating that arterial stiffening with exercise is at least partially reversible. Further study is required to test effects of agents that target the NO pathway in reducing arterial stiffness in HFpEF. (Study of Exercise and Heart Function in Patients With Heart Failure and Pulmonary Vascular Disease [EXEC]; NCT01418248. Acute Effects of Inorganic Nitrite on Cardiovascular Hemodynamics in Heart Failure With Preserved Ejection Fraction; NCT01932606. Inhaled Sodium Nitrite on Heart Failure With Preserved Ejection Fraction; NCT02262078).

METFORMIN: NONGLYCEMIC EFFECTS AND POTENTIAL NOVEL INDICATIONS

OBJECTIVE

Metformin is the most commonly prescribed drug for the treatment of type 2 diabetes because of its apparent robust effects in reducing cardiovascular risk. This review examines the current literature regarding the nonglycemic effects and potential novel indications for metformin.

METHODS

Review of the literature, with a focus on metformin use in Stage 3 chronic kidney disease (CKD-3) and heart failure (HF).

RESULTS

The United Kingdom Prospective Diabetes Study suggests that metformin reduces the risk of myocardial infarction, and more recent retrospective studies have shown an association between metformin use and a reduction in stroke, atrial fibrillation and all-cause mortality. The mechanism(s) explaining these putative benefits are not clear but may involve decreased energy intake (with attendant weight loss), improvement in lipids, and lowering of blood pressure; a literature review suggests that metformin lowers blood pressure when it is elevated, but not when it is normal. Metformin appears to be safe when given to patients with CKD-3. In addition, there is evidence that individuals with CKD-3, who are at increased cardiovascular risk, stand to benefit from metformin therapy. Lactic acidosis is an extremely remote and probably avoidable risk; measurement of plasma metformin levels and more frequent monitoring of renal function may be useful in selected patients with CKD-3 who are treated with metformin. Finally, there is evidence that metformin is safe in patients with HF; metformin therapy is associated with a reduction in newly incident HF and in HF mortality.

CONCLUSION

Metformin has a dominant position in the treatment of type 2 diabetes that is deserved due to its favorable and robust effects on cardiovascular risk.

ABBREVIATIONS

AMP = adenosine monophosphate BP = blood pressure CKD = chronic kidney disease CKD-3 = Stage 3 CKD eGFR = estimated glomerular filtration rate HDL = high-density lipoprotein HF = heart failure MAP = mean arterial pressure mVO2 = myocardial oxygen consumption T2DM = type 2 diabetes mellitus UKPDS = United Kingdom Prospective Diabetes Study.

Association of Central Adiposity With Adverse Cardiac Mechanics: Findings From the Hypertension Genetic Epidemiology Network Study

BACKGROUND

Central obesity, defined by increased waist circumference or waist:hip ratio (WHR), is associated with increased cardiovascular events, including heart failure. However, the pathophysiological link between central obesity and adverse cardiovascular outcomes remains poorly understood. We hypothesized that central obesity and larger WHR are independently associated with worse cardiac mechanics (reduced left ventricular strain and systolic [s'] and early diastolic [e'] tissue velocities).

METHODS AND RESULTS

We performed speckle-tracking analysis of echocardiograms from participants in the Hypertension Genetic Epidemiology Network (HyperGEN) study, a population- and family-based epidemiological study (n=2181). Multiple indices of systolic and diastolic cardiac mechanics were measured. We evaluated the association between central obesity and cardiac mechanics using multivariable-adjusted linear mixed-effects models to account for relatedness among participants. The mean age of the cohort was 51±14 years, 58% were women, and 47% were black. Mean body mass index was 30.8±7.1 kg/m(2), waist circumference was 102±17 cm, WHR was 0.91±0.08, and 80% had central obesity based on waist circumference and WHR criteria. After adjusting for multiple potential confounders (including age, sex, race, physical activity, body mass index, heart rate, smoking status, systolic blood pressure, fasting glucose, total cholesterol, antihypertensive medication use, glomerular filtration rate, left ventricular mass index, wall motion abnormalities, and ejection fraction), central obesity and WHR remained associated with worse global longitudinal strain, early diastolic strain rate, s' velocity, and e' velocity (P<0.05 for all comparisons). There were no significant statistical interactions between WHR and obesity status.

CONCLUSIONS

In this cross-sectional study of participants with multiple comorbidities, central obesity was found to be associated with adverse cardiac mechanics.

Evidence Supporting the Existence of a Distinct Obese Phenotype of Heart Failure With Preserved Ejection Fraction

BACKGROUND

Heart failure (HF) with preserved ejection fraction (HFpEF) is a heterogeneous syndrome. Phenotyping patients into pathophysiologically homogeneous groups may enable better targeting of treatment. Obesity is common in HFpEF and has many cardiovascular effects, suggesting that it may be a viable candidate for phenotyping. We compared cardiovascular structure, function, and reserve capacity in subjects with obese HFpEF, those with nonobese HFpEF, and control subjects.

METHODS

Subjects with obese HFpEF (body mass index ≥35 kg/m²; n=99), nonobese HFpEF (body mass index <30 kg/m²; n=96), and nonobese control subjects free of HF (n=71) underwent detailed clinical assessment, echocardiography, and invasive hemodynamic exercise testing.

RESULTS

Compared with both subjects with nonobese HFpEF and control subjects, subjects with obese HFpEF displayed increased plasma volume (3907 mL [3563-4333 mL] versus 2772 mL [2555-3133 mL], and 2680 mL [2380-3006 mL]; P<0.0001), more concentric left ventricular remodeling, greater right ventricular dilatation (base, 34±7 versus 31±6 and 30±6 mm, P=0.0005; length, 66±7 versus 61±7 and 61±7 mm, P<0.0001), more right ventricular dysfunction, increased epicardial fat thickness (10±2 versus 7±2 and 6±2 mm; P<0.0001), and greater total epicardial heart volume (945 mL [831-1105 mL] versus 797 mL [643-979 mL] and 632 mL [517-768 mL]; P<0.0001), despite lower N-terminal pro-B-type natriuretic peptide levels. Pulmonary capillary wedge pressure was correlated with body mass and plasma volume in obese HFpEF (r=0.22 and 0.27, both P<0.05) but not in nonobese HFpEF (P≥0.3). The increase in heart volumes in obese HFpEF was associated with greater pericardial restraint and heightened ventricular interdependence, reflected by increased ratio of right- to left-sided heart filling pressures (0.64±0.17 versus 0.56±0.19 and 0.53±0.20; P=0.0004), higher pulmonary venous pressure relative to left ventricular transmural pressure, and greater left ventricular eccentricity index (1.10±0.19 versus 0.99±0.06 and 0.97±0.12; P<0.0001). Interdependence was enhanced as pulmonary artery pressure load increased (P for interaction <0.05). Compared with those with nonobese HFpEF and control subjects, obese patients with HFpEF displayed worse exercise capacity (peak oxygen consumption, 7.7±2.3 versus 10.0±3.4 and12.9±4.0 mL/min·kg; P<0.0001), higher biventricular filling pressures with exercise, and depressed pulmonary artery vasodilator reserve.

CONCLUSIONS

Obesity-related HFpEF is a genuine form of cardiac failure and a clinically relevant phenotype that may require specific treatments.

Relationship Between Physical Activity, Body Mass Index, and Risk of Heart Failure

BACKGROUND

Lower leisure-time physical activity (LTPA) and higher body mass index (BMI) are independently associated with risk of heart failure (HF). However, it is unclear if this relationship is consistent for both heart failure with preserved ejection fraction (HFpEF) and heart failure with reduced ejection fraction (HFrEF).

OBJECTIVES

This study sought to quantify dose-response associations between LTPA, BMI, and the risk of different HF subtypes.

METHODS

Individual-level data from 3 cohort studies (WHI [Women's Health Initiative], MESA [Multi-Ethnic Study of Atherosclerosis], and CHS [Cardiovascular Health Study]) were pooled and participants were stratified into guideline-recommended categories of LTPA and BMI. Associations between LTPA, BMI, and risk of overall HF, HFpEF (ejection fraction ≥45%), and HFrEF (ejection fraction <45%) were assessed by using multivariable adjusted Cox models and restricted cubic splines.

RESULTS

The study included 51,451 participants with 3,180 HF events (1,252 HFpEF, 914 HFrEF, and 1,014 unclassified HF). In the adjusted analysis, there was a dose-dependent association between higher LTPA levels, lower BMI, and overall HF risk. Among HF subtypes, LTPA in any dose range was not associated with HFrEF risk. In contrast, lower levels of LTPA (<500 MET-min/week) were not associated with HFpEF risk, and dose-dependent associations with lower HFpEF risk were observed at higher levels. Compared with no LTPA, higher than twice the guideline-recommended minimum LTPA levels (>1,000 MET-min/week) were associated with an 19% lower risk of HFpEF (hazard ratio: 0.81; 95% confidence interval: 0.68 to 0.97). The dose-response relationship for BMI with HFpEF risk was also more consistent than with HFrEF risk, such that increasing BMI above the normal range (≥25 kg/m2) was associated with a greater increase in risk of HFpEF than HFrEF.

CONCLUSIONS

Our study findings show strong, dose-dependent associations between LTPA levels, BMI, and risk of overall HF. Among HF subtypes, higher LTPA levels and lower BMI were more consistently associated with lower risk of HFpEF compared with HFrEF.

Race-Related Differences in Left Ventricular Structural and Functional Remodeling in Response to Increased Afterload: The ARIC Study

OBJECTIVES

The aim of this study was to evaluate racial differences in arterial elastance (Ea), which reflects the arterial afterload faced by the left ventricle, and its associations with cardiac structure and function. The hypothesis under study was that the left ventricle in blacks displays heightened afterload sensitivity compared with whites.

BACKGROUND

Chronic increasing in arterial afterload may be an important trigger for left ventricular (LV) remodeling and dysfunction that lead to heart failure. Racial differences in the predisposition to heart failure are well described, but the underlying mechanisms remain unclear.

METHODS

In total, 5,727 community-based, older ARIC (Atherosclerosis Risk In Community) study participants (22% black) who underwent echocardiography between 2011 and 2013 were studied.

RESULTS

Blacks were younger (mean age 75 ± 5 years vs. 76 ± 5 years), were more frequently female (66% vs. 57%), and had higher prevalence rates of obesity (46% vs. 31%), hypertension (94% vs. 80%), and diabetes mellitus (47% vs. 34%) than whites. Adjusting for these baseline differences, Ea was higher among blacks (1.96 ± 0.01 mm Hg/ml vs. 1.80 ± 0.01 mm Hg/ml). In blacks, Ea was associated with greater LV remodeling (LV mass index, β = 3.21 ± 0.55 g/m2, p < 0.001) and higher LV filling pressures (E/e' ratio, β = 0.42 ± 0.11, p < 0.001). These relationships were not observed in whites (LV mass, β = 0.16 ± 0.32 g/m2, p = 0.61, p for interaction <0.001; E/e' ratio, β = -0.32 ± 0.06, p < 0.001, p for interaction <0.001).

CONCLUSIONS

These community-based data suggest that black Americans display heightened afterload sensitivity as a stimulus for LV structural and functional remodeling, which may contribute to their greater risk for heart failure compared with white Americans.

Phenotype-Specific Treatment of Heart Failure With Preserved Ejection Fraction: A Multiorgan Roadmap

Heart failure (HF) with preserved ejection fraction (EF; HFpEF) accounts for 50% of HF cases, and its prevalence relative to HF with reduced EF continues to rise. In contrast to HF with reduced EF, large trials testing neurohumoral inhibition in HFpEF failed to reach a positive outcome. This failure was recently attributed to distinct systemic and myocardial signaling in HFpEF and to diversity of HFpEF phenotypes. In this review, an HFpEF treatment strategy is proposed that addresses HFpEF-specific signaling and phenotypic diversity. In HFpEF, extracardiac comorbidities such as metabolic risk, arterial hypertension, and renal insufficiency drive left ventricular remodeling and dysfunction through systemic inflammation and coronary microvascular endothelial dysfunction. The latter affects left ventricular diastolic dysfunction through macrophage infiltration, resulting in interstitial fibrosis, and through altered paracrine signaling to cardiomyocytes, which become hypertrophied and stiff because of low nitric oxide and cyclic guanosine monophosphate. Systemic inflammation also affects other organs such as lungs, skeletal muscle, and kidneys, leading, respectively, to pulmonary hypertension, muscle weakness, and sodium retention. Individual steps of these signaling cascades can be targeted by specific interventions: metabolic risk by caloric restriction, systemic inflammation by statins, pulmonary hypertension by phosphodiesterase 5 inhibitors, muscle weakness by exercise training, sodium retention by diuretics and monitoring devices, myocardial nitric oxide bioavailability by inorganic nitrate-nitrite, myocardial cyclic guanosine monophosphate content by neprilysin or phosphodiesterase 9 inhibition, and myocardial fibrosis by spironolactone. Because of phenotypic diversity in HFpEF, personalized therapeutic strategies are proposed, which are configured in a matrix with HFpEF presentations in the abscissa and HFpEF predispositions in the ordinate.

Sex disparity in the association between hypertriglyceridemic waist phenotype and arterial stiffness in Chinese healthy subjects

OBJECTIVE

To investigate the association between hypertriglyceridemic waist (HTGW) phenotype and arterial stiffness in a Chinese population without hypertension, diabetes and cardiovascular diseases.

METHODS

A total number of 3028 subjects aged 40 years and over were enrolled in this cross-sectional study. All participants provided a clinical history and underwent a physical examination. Brachial-ankle pulse wave velocity (baPWV) was used to evaluate arterial stiffness. HTGW phenotype was defined as the simultaneous presence of waist circumference ≥90/80 cm and triglycerides ≥2.0/1.5 mmol/L in men/women.

RESULTS

The prevalence of HTGW phenotype was 7.5% among healthy participants in China (Beijing), 7.4% in men and 7.5% in women. Women with HTGW phenotype had a higher level of baPWV compared with normal WC and normal triglyceride (NWNT) group (P < 0.05), but no significant difference was observed in men (P > 0.05). Multiple logistic regression analysis showed HTGW phenotype was significantly associated with baPWV after controlling for multiple factors in women. However, no significant relationship was observed in men.

CONCLUSIONS

The present study supports that HTGW phenotype is associated with increased arterial stiffness in women but not in men.

Nrf2 signaling and redox homeostasis in the aging heart: A potential target to prevent cardiovascular diseases?

Aging process is often accompanied with a high incidence of cardiovascular diseases (CVD) due to the synergistic effects of age-related changes in heart morphology/function and prolonged exposure to injurious effects of CVD risk factors. Oxidative stress, considered a hallmark of aging, is also an important feature in pathologies that predispose to CVD development, like hypertension, diabetes and obesity. Approaches directed to prevent the occurrence of CVD during aging have been explored both in experimental models and in controlled clinical trials, in order to improve health span, reduce hospitalizations and increase life quality during elderly. In this review we discuss oxidative stress role as a main risk factor that relates CVD with aging. As well as interventions that aim to reduce oxidative stress by supplementing with exogenous antioxidants. In particular, strategies of improving the endogenous antioxidant defenses through activating the nuclear factor related-2 factor (Nrf2) pathway; one of the best studied molecules in cellular redox homeostasis and a master regulator of the antioxidant and phase II detoxification response.

Preclinical Systolic and Diastolic Dysfunctions in Metabolically Healthy and Unhealthy Obese Individuals

BACKGROUND

Despite the substantial overlap of obesity and metabolic disease, there is heterogeneity with respect to cardiovascular risk. We sought to investigate preclinical differences in systolic and diastolic function in obesity, and specifically compare obese individuals with and without metabolic syndrome (MS).

METHODS AND RESULTS

Obese individuals without cardiac disease with (OB/MS+, n=124) and without (OB/MS-, n=37) MS were compared with nonobese controls (n=29). Diastolic function was assessed by transmitral and tissue Doppler. Global longitudinal strain (LS) and time-based dyssynchrony were assessed by speckle tracking. Both OB/MS- and OB/MS+ groups had similar ejection fraction but worse systolic mechanics as assessed by LS and dyssynchrony when compared with nonobese controls. Specifically, OB/MS- had 2.5% lower LS (SE, 0.7%; P=0.001 in multivariable-adjusted analyses) and 10.8 ms greater dyssynchrony (SE, 3.3 ms; P=0.002), and OB/MS+ had 1.0% lower LS (SE, 0.3%; P<0.001) and 7.8 ms greater dyssynchrony (SE, 1.5 ms; P<0.001) when compared with controls. Obesity was associated with impaired diastolic function regardless of MS status, as evidenced by greater left atrial diameter and left ventricular mass although diastolic dysfunction was more pronounced in OB/MS+ than in OB/MS- individuals.

CONCLUSIONS

Obesity is associated with subclinical differences in both systolic and diastolic function regardless of the presence or absence of MS although MS seems to be associated with worse diastolic dysfunction. When compared with controls, metabolically healthy obese had lower LS, greater dyssynchrony, and early diastolic dysfunction, supporting the notion that obesity per se may have adverse cardiovascular effects regardless of metabolic disease.

Heart failure with preserved ejection fraction in the elderly: scope of the problem

Heart failure with preserved ejection fraction (HFpEF) is the most common form of heart failure (HF) in older adults, particularly women, and is increasing in prevalence as the population ages. With morbidity and mortality on par with HF with reduced ejection fraction, it remains a most challenging clinical syndrome for the practicing clinician and basic research scientist. Originally considered to be predominantly caused by diastolic dysfunction, more recent insights indicate that HFpEF in older persons is typified by a broad range of cardiac and non-cardiac abnormalities and reduced reserve capacity in multiple organ systems. The globally reduced reserve capacity is driven by: 1) inherent age-related changes; 2) multiple, concomitant co-morbidities; 3) HFpEF itself, which is likely a systemic disorder. These insights help explain why: 1) co-morbidities are among the strongest predictors of outcomes; 2) approximately 50% of clinical events in HFpEF patients are non-cardiovascular; 3) clinical drug trials in HFpEF have been negative on their primary outcomes. Embracing HFpEF as a true geriatric syndrome, with complex, multi-factorial pathophysiology and clinical heterogeneity could provide new mechanistic insights and opportunities for progress in management. This article is part of a Special Issue entitled CV Aging.

Use of metformin in diseases of aging

Metformin is the most commonly prescribed medication for type 2 diabetes (T2DM) in the world. It has primacy in the treatment of this disease because of its safety record and also because of evidence for reduction in the risk of cardiovascular events. Evidence has accumulated indicating that metformin is safe in people with stage 3 chronic kidney disease (CKD-3). It is estimated that roughly one-quarter of people with CKD-3 and T2DM in the United States (well over 1 million) are ineligible for metformin treatment because of elevated serum creatinine levels. This could be overcome if a scheme, perhaps based on pharmacokinetic studies, could be developed to prescribe reduced doses of metformin in these individuals. There is also substantial evidence from epidemiologic studies to indicate that metformin may not only be safe, but may actually benefit people with heart failure (HF). Prospective, randomized trials of the use of metformin in HF are needed to investigate this possibility.