Differences in neurohormonal activity partially explain the obesity paradox in patients with heart failure: The role of sympathetic activation

Associations of Obesity and Prognostic Nutritional Index on 1-Year Mortality in Patients with Acute Heart Failure

Background

Increased BMI is paradoxically associated with improved survival among patients with acute heart failure (AHF). However, the impact of different nutritional status on this obesity paradox on 1-year mortality is underreported. The prognostic nutritional index is a simple tool to assess nutrition status.

Methods

From 10,027 emergency department admissions at the Amager and Hvidovre Hospital, Copenhagen University Hospital in Denmark, all patients with AHF were identified. Patients were categorised by BMI (normal: 18.5-24.9 kg/m2, overweight: 25-29.9 kg/m2, obese: ≥30 kg/m2) and nutritional status using the prognostic nutritional index (malnourished: <38, well-nourished: ≥38). Kaplan- Meier curves analysed cumulative survival, and Cox regression examined associations between BMI, nutritional status and outcomes, expressed as HR and 95% CI.

Results

Among 383 AHF patients (median age 76 years), 41.3% were malnourished and 58.7% well nourished. In the well-nourished group, obesity was inversely associated with 1-year mortality (adjusted HR 0.48; 95% CI [0.24-0.95]; p=0.035). However, this correlation disappeared in the malnourished group (adjusted HR 1.08; 95% CI [0.59-2.00]; p=0.798). Mortality rates were significantly lower in the well-nourished group among patients with overweight and obesity.

Conclusion

Obesity was associated with reduced 1-year mortality only in AHF patients with good nutritional status, while in malnourished patients, obesity was not associated with 1-year mortality. The prognosis in patients with AHF depends on both the presence of obesity and their nutritional status, highlighting the need for nutritional assessment for risk stratification.

No Obesity Paradox for Health-Related Quality of Life in Patients with Heart Failure and Reduced Ejection Fraction: Insights from the VIDA Multicenter Study

Background and Objectives: Previous studies showed that, paradoxically, obese patients with heart failure (HF) have better clinical outcomes compared to overweight, normal, or underweight patients. Scientific societies emphasize the importance of integrating quality of life (QoL) assessment in cardiovascular care. However, the association between QoL and weight remains understudied. Given the significant correlation between HF survival and QoL, it is essential to assess how obesity impacts patient-reported outcomes in this clinical setting. Methods: This cross-sectional multicenter study in 1028 HF patients with reduced ejection fraction (HFrEF) aims to evaluate the association between obesity and QoL, and whether the obesity paradox holds for HF patients regarding QoL. Specific and generic QoL questionnaires were administered alongside clinical parameters like body mass index (BMI) and body adiposity estimator (BAE). Results: Obese compared to non-obese reported worse QoL. In the adjusted linear regression models, neither BMI nor obesity were associated with QoL. Generalized additive models confirmed a strong non-parametric association between BMI, subdomain scores from Kansas City Cardiomyopathy Questionnaire (KCCQ) (OSS p = 0.004, CSS p = 0.006, TSS p = 0.02), and summary measurements of EQ-5D (EQ-5D index p = 0.003, visual analogue scale (VAS) p = 0.01). In contrast, BAE showed a statistically significant linear relation among QoL (OSS p ≤ 0.001, CSS p ≤ 0.001, TSS p ≤ 0.001) and EQ-5D summary measurements (EQ-5D index p ≤ 0.001, VAS p ≤ 0.001). Conclusions: Overall, obese patients have worse QoL; therefore, obesity cannot be considered a protective factor in terms of QoL in established HF.

Reduced thoracic skeletal muscle size is associated with adverse outcomes in diabetes patients with heart failure and reduced ejection fraction: quantitative analysis of sarcopenia by using cardiac MRI

BACKGROUND

Sarcopenia is frequently found in patients with heart failure with reduced ejection fraction (HFrEF) and is associated with reduced exercise capacity, poor quality of life and adverse outcomes. Recent evidence suggests that axial thoracic skeletal muscle size could be used as a surrogate to assess sarcopenia in HFrEF. Since diabetes mellitus (DM) is one of the most common comorbidities with HFrEF, we aimed to explore the potential association of axial thoracic skeletal muscle size with left ventricular (LV) remodeling and determine its prognostic significance in this condition.

METHODS

A total of 243 diabetes patients with HFrEF were included in this study. Bilateral axial thoracic skeletal muscle size was obtained using cardiac MRI. Patients were stratified by the tertiles of axial thoracic skeletal muscle index (SMI). LV structural and functional indices, as well as amino-terminal pro-B-type natriuretic peptide (NT-proBNP), were measured. The determinants of elevated NT-proBNP were assessed using linear regression analysis. The associations between thoracic SMI and clinical outcomes were assessed using a multivariable Cox proportional hazards model.

RESULTS

Patients in the lowest tertile of thoracic SMI displayed a deterioration in LV systolic strain in three components, together with an increase in LV mass and a heavier burden of myocardial fibrosis (all P < 0.05). Moreover, thoracic SMI (β = -0.25; P < 0.001), rather than body mass index (β = -0.04; P = 0.55), was independently associated with the level of NT-proBNP. The median follow-up duration was 33.6 months (IQR, 20.4-52.8 months). Patients with adverse outcomes showed a lower thoracic SMI (40.1 [34.3, 47.9] cm2/m2 vs. 45.3 [37.3, 55.0] cm2/m2; P < 0.05) but a similar BMI (P = 0.76) compared with those without adverse outcomes. A higher thoracic SMI indicated a lower risk of adverse outcomes (hazard ratio: 0.96; 95% confidence interval: 0.92-0.99; P = 0.01).

CONCLUSIONS

With respect to diabetes patients with HFrEF, thoracic SMI is a novel alternative for evaluating muscle wasting in sarcopenia that can be obtained by a readily available routine cardiac MRI protocol. A reduction in thoracic skeletal muscle size predicts poor outcomes in the context of DM with HFrEF.

Overweight and obesity are associated with better survival in STEMI patients with diabetes

OBJECTIVE

The relationship between obesity and in-hospital outcomes in individuals with type 2 diabetes mellitus (T2DM) who develop an ST-elevation myocardial infarction (STEMI) was assessed.

METHODS

Data from the National Inpatient Sample (NIS) from 2008 to 2017 were analyzed. Patients with STEMI and T2DM were classified as being underweight or having normal weight, overweight, obesity, and severe obesity. The temporal trend of those BMI ranges and in-hospital outcomes among different obesity groups were assessed.

RESULTS

A total of 74,099 patients with T2DM and STEMI were included in this analysis. In 2008, 35.8% of patients had obesity, and 37.3% had severe obesity. However, patients with obesity accounted for most of the study population in 2017 (57.8%). During the observation period, mortality decreased in underweight patients from 18.1% to 13.2% (p < 0.001). Still, it gradually increased in all other BMI ranges, along with cardiogenic shock, atrial fibrillation, and ventricular fibrillation (p < 0.001 for all). After the combination of all patients during the observation period, mortality was lower in patients with overweight and obesity (adjusted odds ratio = 0.625 [95% CI 0.499-0.784]; 0.606 [95% CI 0.502-0.733], respectively).

CONCLUSIONS

A U-shaped association governs the relationship between BMI and mortality in STEMI patients with diabetes, with those having overweight and obesity experiencing better survival.

Soluble Transferrin Receptor as Iron Deficiency Biomarker: Impact on Exercise Capacity in Heart Failure Patients

The soluble transferrin receptor (sTfR) is a marker of tissue iron status, which could indicate an increased iron demand at the tissue level. The impact of sTfR levels on functional capacity and quality of life (QoL) in non-anemic heart failure (HF) patients with otherwise normal systemic iron status has not been evaluated. We conducted an observational, prospective, cohort study of 1236 patients with chronic HF. We selected patients with normal hemoglobin levels and normal systemic iron status. Tissue iron deficiency (ID) was defined as levels of sTfR > 75th percentile (1.63 mg per L). The primary endpoints were the distance walked in the 6 min walking test (6MWT) and the overall summary score (OSS) of the Minnesota Living with Heart Failure Questionnaire (MLHFQ). The final study cohort consisted of 215 patients. Overall QoL was significantly worse (51 ± 27 vs. 39 ± 20, p-value = 0.006, respectively), and the 6 MWT distance was significantly worse in patients with tissue ID when compared to patients without tissue ID (206 ± 179 m vs. 314 ± 155, p-value < 0.0001, respectively). Higher sTfR levels, indicating increased iron demand, were associated with a shorter distance in the 6 MWT (standardized β = -0.249, p < 0.001) and a higher MLHFQ OSS (standardized β = 0.183, p-value = 0.008). In this study, we show that in patients with normal systemic iron parameters, higher levels of sTfR are strongly associated with an impaired submaximal exercise capacity and with worse QoL.

Exploring the prevalence, impact and experience of cardiac cachexia in patients with advanced heart failure and their caregivers: A sequential phased study

BACKGROUND

Cardiac Cachexia is a wasting syndrome that has a significant impact on patient mortality and quality of life world-wide, although it is poorly understood in clinical practice.

AIM

Identify the prevalence of cardiac cachexia in patients with advanced New York Heart Association (NYHA) functional class and explore its impact on patients and caregivers.

DESIGN

An exploratory cross-sectional study. The sequential approach had two phases, with phase 1 including 200 patients with NYHA III-IV heart failure assessed for characteristics of cardiac cachexia. Phase 2 focussed on semi-structured interviews with eight cachectic patients and five caregivers to ascertain the impact of the syndrome.

SETTING/PARTICIPANTS

Two healthcare trusts within the United Kingdom.

RESULTS

Cardiac Cachexia was identified in 30 out of 200 participants, giving a prevalence rate of 15%. People with cachexia had a significantly reduced average weight and anthropometric measures (p < 0.05). Furthermore, individuals with cachexia experienced significantly more fatigue, had greater issues with diet and appetite, reduced physical wellbeing and overall reduced quality of life. C-reactive protein was significantly increased, whilst albumin and red blood cell count were significantly decreased in the cachectic group (p < 0.05). From qualitative data, four key themes were identified: (1) 'Changed relationship with food and eating', (2) 'Not me in the mirror', (3) 'Lack of understanding regarding cachexia' and (4) 'Uncertainty regarding the future'.

CONCLUSIONS

Cardiac cachexia has a debilitating effect on patients and caregivers. Future work should focus on establishing a specific definition and clinical pathway to enhance patient and caregiver support.

Malnutrition outweighs the effect of the obesity paradox

BACKGROUND

High body mass index (BMI) is paradoxically associated with better outcome in patients with heart failure (HF). The effects of malnutrition on this phenomenon across the whole spectrum of HF have not yet been studied.

METHODS

In this observational study, patients were classified by guideline diagnostic criteria to one of three heart failure subtypes: reduced (HFrEF), mildy reduced (HFmrEF), and preserved ejection fraction (HFpEF). Data were retrieved from the Viennese-community healthcare provider network between 2010 and 2020. The relationship between BMI, nutritional status reflected by the prognostic nutritional index (PNI), and survival was assessed. Patients were classified by the presence (PNI < 45) or absence (PNI ≥ 45) of malnutrition.

RESULTS

Of the 11 995 patients enrolled, 6916 (58%) were classified as HFpEF, 2809 (23%) HFmrEF, and 2270 HFrEF (19%). Median age was 70 years (IQR 61-77), and 67% of patients were men. During a median follow-up time of 44 months (IQR 19-76), 3718 (31%) of patients died. After adjustment for potential confounders, BMI per IQR increase was independently associated with better survival (adj. hazard ratio [HR]: 0.91 [CI 0.86-0.97], P = 0.005), this association remained significant after additional adjustment for HF type (adj. HR: 0.92 [CI 0.86-0.98], P = 0.011). PNI was available in 10 005 patients and lowest in HFrEF patients. PNI was independently associated with improved survival (adj. HR: 0.96 [CI 0.95-0.97], P < 0.001); additional adjustment for HF type yielded similar results (adj. HR: 0.96 [CI 0.96-0.97], P < 0.001). Although obese patients experienced a 30% risk reduction, malnutrition at least doubled the risk for death with 1.8- to 2.5-fold higher hazards for patients with poor nutritional status compared with normal weight well-nourished patients.

CONCLUSIONS

The obesity paradox seems to be an inherent characteristic of HF regardless of phenotype and nutritional status. Yet malnutrition significantly changes trajectory of outcome with regard to BMI alone: obese patients with malnutrition have a considerably worse outcome compared with their well-nourished counterparts, outweighing protective effects of high BMI alone. In this context, routine recommendation towards weight loss in patients with obesity and HF should generally be made with caution and focus should be shifted on nutritional status.

Blood Differential Gene Expression in Patients with Chronic Heart Failure and Systemic Iron Deficiency: Pathways Involved in Pathophysiology and Impact on Clinical Outcomes

Background: Iron deficiency is a common disorder in patients with heart failure and is related with adverse outcomes and poor quality of life. Previous experimental studies have shown biological connections between iron homeostasis, mitochondrial metabolism, and myocardial function. However, the mechanisms involved in this crosstalk are yet to be unfolded. Methods: The present research attempts to investigate the intrinsic biological mechanisms between heart failure and iron deficiency and to identify potential prognostic biomarkers by determining the gene expression pattern in the blood of heart failure patients, using whole transcriptome and targeted TaqMan^® low-density array analyses. Results: We performed a stepwise cross-sectional longitudinal study in a cohort of chronic heart failure patients with and without systemic iron deficiency. First, the full transcriptome was performed in a nested case-control exploratory cohort of 7 paired patients and underscored 1128 differentially expressed transcripts according to iron status (cohort1#). Later, we analyzed the messenger RNA levels of 22 genes selected by their statistical significance and pathophysiological relevance, in a validation cohort of 71 patients (cohort 2#). Patients with systemic iron deficiency presented lower mRNA levels of mitochondrial ferritin, sirtuin-7, small integral membrane protein 20, adrenomedullin and endothelin converting enzyme-1. An intermediate mitochondrial ferritin gene expression and an intermediate or low sirtuin7 and small integral membrane protein 20 mRNA levels were associated with an increased risk of all-cause mortality and heart failure admission ((HR 2.40, 95% CI 1.04–5.50, p-value = 0.039), (HR 5.49, 95% CI 1.78–16.92, p-value = 0.003), (HR 9.51, 95% CI 2.69–33.53, p-value < 0.001), respectively). Conclusions: Patients with chronic heart failure present different patterns of blood gene expression depending on systemic iron status that affect pivotal genes involved in iron regulation, mitochondrial metabolism, endothelial function and cardiovascular physiology, and correlate with adverse clinical outcomes.

Natriuretic Peptide Clearance Receptor (NPR-C) Pathway as a Novel Therapeutic Target in Obesity-Related Heart Failure With Preserved Ejection Fraction (HFpEF)

Heart failure (HF) with preserved ejection fraction (HFpEF) is a major public health problem with cases projected to double over the next two decades. There are currently no US Food and Drug Administration–approved therapies for the health-related outcomes of HFpEF. However, considering the high prevalence of this heterogeneous syndrome, a directed therapy for HFpEF is one the greatest unmet needs in cardiovascular medicine. Additionally, there is currently a lack of mechanistic understanding about the pathobiology of HFpEF. The phenotyping of HFpEF patients into pathobiological homogenous groups may not only be the first step in understanding the molecular mechanism but may also enable the development of novel targeted therapies. As obesity is one of the most common comorbidities found in HFpEF patients and is associated with many cardiovascular effects, it is a viable candidate for phenotyping. Large outcome trials and registries reveal that being obese is one of the strongest independent risk factors for developing HFpEF and that this excess risk may not be explained by traditional cardiovascular risk factors. Recently, there has been increased interest in the intertissue communication between adipose tissue and the heart. Evidence suggests that the natriuretic peptide clearance receptor (NPR-C) pathway may play a role in the development and pathobiology of obesity-related HFpEF. Therefore, therapeutic manipulations of the NPR-C pathway may represent a new pharmacological strategy in the context of underlying molecular mechanisms.

The relationship between self-care, long-term mortality, and heart failure hospitalization: insights from a real-world cohort study

AIMS

The assumption that improved self-care in the setting of heart failure (HF) care necessarily translates into improvements in long-term mortality and/or hospitalization is not well established. We aimed to study the association between self-care and long-term mortality and other major adverse HF events (MAHFE).

METHODS AND RESULTS

We conducted an observational, prospective, cohort study of 1123 consecutive patients with chronic HF. The primary endpoint was all-cause mortality. We used the European Heart Failure Self-care Behaviour Scale 9-item version (EHFSCBS-9) to measure global self-care (overall score) and three specific dimensions of self-care including autonomy-based adherence, consulting behaviour and provider-based adherence. After a mean follow-up of 3.3 years, all-cause death occurred in 487 patients (43%). In adjusted analysis, higher EHFScBS-9 scores (better self-care) at baseline were associated with lower risk of all-cause death [hazard ratio (HR) 0.993, 95% confidence interval (CI) (0.988-0.997), P-value = 0.002], cardiovascular (CV) death [HR 0.989, 95% CI (0.981-0.996), P-value = 0.003], HF hospitalization [HR 0.993, 95% CI (0.988-0.998), P-value = 0.005], and the combination of MAHFE [HR 0.995, 95% CI (0.991-0.999), P-value = 0.018]. Similarly, impaired global self-care [HR 1.589, 95% CI (1.201-2.127), P-value = 0.001], impaired autonomy-based adherence [HR 1.464, 95% CI (1.114-1.923), P-value = 0.006], and impaired consulting behaviour dimensions [HR 1.510, 95% CI (1.140-1.923), P-value = 0.006] were all associated with higher risk of all-cause mortality.

CONCLUSION

In this study, we have shown that worse self-care is an independent predictor of long-term mortality (both, all-cause and CV), HF hospitalization, and the combinations of these endpoints in patients with chronic HF. Important dimensions of self-care such as autonomy-based adherence and consulting behaviour also determine the risk of all these outcomes in the long term.

Sympathetic activation and outcomes in chronic heart failure: Does the neurohormonal hypothesis apply to mid-range and preserved ejection fraction patients?

BACKGROUND

Sympathetic activity (SA) is increased in patients with heart failure and reduced ejection fraction (HFrEF) and is associated with poor outcomes. However, its clinical implications are less understood in HF with mid-range (HFmrEF) and preserved ejection fraction (HFpEF). We aimed to study SA across left ventricle ejection fraction (LVEF) groups and its association with clinical outcomes.

METHODS AND RESULTS

SA estimated by norepinephrine (NE) levels was determined in 742 consecutive outpatients with chronic HF: 348 (47%) with HFrEF, 116 (16%) HFmrEF, and 278 (37%) HFpEF. After a mean follow-up of 15 months, 17% died. Adjusted analyses showed that patients with HFpEF and HFmrEF had lower estimated marginal means of NE levels compared to HFrEF (278 and 116 pg/mL, respectively, vs. 348 pg/mL; p-value=0.005). Adjusted Cox regression analyses showed that high norepinephrine levels independently predicted all-cause mortality (ACM) in all 3 groups. The strongest associations between high NE levels and cardiovascular mortality (CVM) were observed in HFmrEF (HR: 4.7 [1.33-16.68]), while the weakest association was in HFpEF (HR: 2.62 [1.08-6.35]).

CONCLUSIONS

Adjusted analyses showed that HFpEF and HFmrEF were associated with lower SA compared to HFrEF. Nevertheless, increasing NE levels were independently associated with ACM and CVM in all three LVEF groups. The strongest association between high NE levels and CVM was present in HFmrEF patients, while the weakest was seen in HFpEF. These findings could explain why the response to neurohormonal therapies in patients with HFmrEF is similar to that of patients with HFrEF rather than with HFpEF.

Association Between Norepinephrine Levels and Abnormal Iron Status in Patients With Chronic Heart Failure: Is Iron Deficiency More Than a Comorbidity?

Background

Mechanisms underlying iron homeostasis dysregulation in patients with chronic heart failure remain unsettled. In cardiomyocyte models, norepinephrine may lead to intracellular iron depletion, but the potential association between catecholamines (sympathetic activation markers) and iron metabolism biomarkers in chronic heart failure is unknown.

Methods and Results

In this cross‐sectional analysis, we studied the association between plasma norepinephrine levels and serum iron status biomarkers indicating iron storage (ferritin), iron transport (transferrin saturation), and iron demand (soluble transferrin receptor) in a prospective cohort of 742 chronic heart failure patients (mean age, 72±11 years; 56% male). Impaired iron status was defined as ferritin <100 μg/L or transferrin saturation <20%. Impaired iron status was observed in 69% of patients. In multivariate models, greater norepinephrine levels were associated with impaired iron transport (transferrin saturation <20%, odds ratio=2.28; 95% CI [1.19–4.35]; P=0.013), but not with impaired iron storage (ferritin <100 μg/L, odds ratio=1.25; 95% CI [0.73–2.16]; P=0.415). Norepinephrine was a significant predictor of increased iron demand (soluble transferrin receptor, standardized β‐coefficient=0.12; P=0.006) and low transferrin saturation (standardized β‐coefficient=−0.12; P=0.003). However, norepinephrine levels were not associated with iron or ferritin levels (P>0.05). Adjusted norepinephrine marginal means were significantly higher in patients with impaired iron status compared with those with normal iron status (528 pg/mL [505–551] versus 482 pg/mL [448–518], respectively; P=0.038).

Conclusions

In chronic heart failure patients, increased sympathetic activation estimated with norepinephrine levels is associated with impaired iron status and, particularly, dysregulation of biomarkers suggesting impaired iron transport and increased iron demand. Whether the relationship between norepinephrine and iron metabolism is bidirectional and entails causality need to be elucidated in future research.

Short-term mortality in end-stage heart failure patients

Objectives

This study is aimed at analyzing the impact of the main factors contributing to short and long-term mortality in patients at final stages of heart failure (HF).

Setting

Patients attended at any of the 279 primary health care centers belonging to the Institut Català de la Salut, in Catalonia (Spain).

Participants

Patients with Advanced HF.

Design

Multicenter cohort study including 1148 HF patients followed for one-year after reaching New York Heart Association (NYHA) IV.

Main measurements

The primary outcome was all-cause mortality. Multivariate logistic regression models were performed to assess the outcomes at 1, 3, 6, and 12 months.

Results

Mean age of patients was 82 (SD 9) years and women represented 61.7%. A total of 135 (11.8%) and 397 (34.6%) patients died three months and one year after inclusion, respectively. Male gender, age, and decreased body mass index were associated with higher mortality at three, six and twelve months. In addition, low systolic blood pressure levels, severe reduction in glomerular filtration, malignancy, and higher doses of loop diuretics were related to higher mortality from 6 to 12 months.

The most important risk factor over the whole period was presenting a body mass index lower than 20 kg/m² (three months OR 3.06, 95% CI: 1.58–5.92; six months OR 4.42, 95% CI: 2.08–9.38; and 12 months OR 3.68, 95% CI: 1.76–7.69).

Conclusions

We may conclude that male, age, and decreased body mass index determined higher short-term mortality in NYHA IV. In addition, low systolic blood pressure, reduced glomerular filtration, malignancy, and higher doses of loop diuretics contribute to increasing the risk of mortality at medium and long-term. Such variables are easily measurable and can help to decide the best way to face the most advances stages of the disease.

Long-Term Weight Gain Associated With High Omentin Levels at Hospital Discharge Improves Prognosis of Patients Following Acute Heart Failure

A obesity paradox has been described following heart failure (HF). The aim of this study was to analyze the association between food intake-involved adipokines and long-term weight changes. Leptin, adiponectin, and omentin were analyzed in 92 acute HF (AHF) patients at discharge, classified on the basis of weight gains or losses > 6%. The mean follow-up was 256 ± 143 days. Leptin and adiponectin levels were similar among weight groups. However, omentin levels were higher in those patients who had gained weight (16 ± 5 ng/mL) than in those who had lost weight (12 ± 4 ng/mL) or showed no weight change (11 ± 5 ng/mL; p < 0.002). Omentin levels were the best independent predictors for patients with weight gain, who had less mortality and hospital readmission during the follow-up. The association between omentin levels and weight gain might explain part of the obesity paradox in HF.

Obesity Paradox in Aging: From Prevalence to Pathophysiology

Recent advances in medical technology and health care have greatly improved the management for chronic diseases and prolonged human lifespan. Unfortunately, increased lifespan and the aging population impose a major challenge on the ever-rising prevalence of chronic diseases, in particular cardiometabolic stress associated with the pandemic obesity in our modern society. Although overweight and obesity are associated with incident cardiovascular diseases (CVD), including heart failure (HF), it paradoxically leads to a more favorable prognosis in patients with chronic HF, a phenomenon commonly defined as "obesity paradox". Numerous population-based and clinical studies have suggested possible explanations such as better metabolic reserve, smoking and disease-associated weight loss for obesity paradox. Recent evidence noticed a shift in obesity paradox with aging. While some studies have reported a more pronounced "obesity paradox" in the older patients, others have seen diminished cardiac benefits with overweight and obesity in the elderly patients with CVD. These findings suggested that a complex relationship among aging, metabolism, and HF severity/chronicity, which may explain the shift in obesity paradox in the elderly. Aging negatively affects body metabolism and cardiac function although its precise impact on obesity paradox remains elusive. To develop new strategies for cardiovascular health in the elderly, it is imperative to understand the precise role for aging on obesity-related CVD.

The short-term effects of indoor size-fractioned particulate matter and black carbon on cardiac autonomic function in COPD patients

BACKGROUND

Previous studies have reported adverse health effects of indoor air pollutants especially particulate matter (PM) and black carbon (BC). Patients with chronic obstructive pulmonary disease (COPD) have been shown to be more likely with cardiovascular comorbidities in which cardiac autonomic dysfunction plays an important role. However, there is little evidence for the effect of indoor PM and BC exposures on cardiac autonomic function in COPD patients.

OBJECTIVES

To evaluate the association between exposure to indoor size-fractioned PM and BC and changes in HRV and HR in COPD patients.

METHODS

Forty-three doctor diagnosed, stable COPD patients were recruited and measured for 24-h HRV and HR. Real-time indoor size-fractioned PM and BC were monitored on the day before and the day of performing health measurements. Mixed-effects models were used to estimate the associations between indoor PM and BC and HRV indices and HR after controlling for potential confounders.

RESULTS

Increasing levels of size-fractioned PM and BC were associated with decreased HRV indices and increased HR. An IQR (3.14μg/m³) increase in 8-h BC moving average and an IQR (20.72μg/m³) increase in 5-min PM_0.5 moving average concentrations were associated with declines of 7.45% (95% CI: -10.89%, -3.88%) and 16.40% (95% CI: -21.06%, -11.41%) in LF, respectively. The smaller the particles size, the greater effects on HRV indices and HR. Patients' BMI modified the associations between size-fractioned PM and BC and their HRV and HR. For an IQR increase in PM_0.5, there was decline in HF of 34.85% (95% CI: -39.08%, -30.33%) in overweight patients, compared to a 2.01% (95% CI: -6.44%, 11.19%) increase in normal-weight patients.

CONCLUSIONS

Exposures to indoor PM and BC were associated with altered cardiac autonomic function in COPD patients, and the associations for HRV measures of parasympathetic activity (e.g., HF) were more apparent in overweight patients.

Influence of Body Mass Index on Long-Term Survival After Cardiac Catheterization

We examined 18,654 patients who underwent cardiac catheterization in a single center to clarify the association between catheterization indication, body mass index (BMI), and long-term survival over a mean follow-up of 81 months. Patients were grouped by indication for catheterization: (a) acute coronary syndromes (ACS), 7,426 patients; (b) coronary artery disease (CAD) evaluation in stable clinical presentation, 6,911 patients; and (c) primarily non-CAD cardiac evaluations, 4,317 patients. Compared with normal weight, overweight and obesity (but not morbid obesity) was associated with lower risk of long-term mortality. Underweight patients had the greatest risk of mortality. After multivariate adjustment, survival benefit of the overweight and obese was retained in the ACS group [hazard ratio 0.86, 95% confidence interval (0.77-0.96), p = 0.006 and 0.79, (0.68-0.91), p = 0.001, respectively] and in overweight patients in the stable presentation CAD group [0.83, (0.72-0.94), p = 0.005], whereas there was no survival benefit in any of the BMI categories in those catheterized primarily for non-CAD indications. Further analysis of matched cohorts showed similar patterns of survival benefit of the overweight/obese. In conclusion, among patients who underwent cardiac catheterization, an inverse association between BMI and long-term mortality was observed, with the lowest risk noted in the overweight and obese population; the obesity paradox was principally demonstrated in patients with ACS, and was eliminated after covariate adjustment in those catheterized primarily for non-CAD indications.

Superoxide Anions and NO in the Paraventricular Nucleus Modulate the Cardiac Sympathetic Afferent Reflex in Obese Rats

This study was conducted to explore the hypothesis that the endogenous superoxide anions (O₂⁻) and nitric oxide (NO) system of the paraventricular nucleus (PVN) regulates the cardiac sympathetic afferent reflex (CSAR) contributing to sympathoexcitation in obese rats induced by a high-fat diet (42% kcal as fat) for 12 weeks. CSAR was evaluated by monitoring the changes of renal sympathetic nerve activity (RSNA) and the mean arterial pressure (MAP) responses to the epicardial application of capsaicin (CAP) in anaesthetized rats. In obese rats with hypertension (OH group) or without hypertension (OB group), the levels of PVN O₂⁻, angiotensinII (Ang II), Ang II type 1 receptor (AT1R), and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase were elevated, whereas neural NO synthase (nNOS) and NO were significantly reduced. Moreover, CSAR was markedly enhanced, which promoted the elevation of plasma norepinephrine levels. The enhanced CSAR was attenuated by PVN application of the superoxide scavenger polyethylene glycol-superoxide dismutase (PEG-SOD) and the NO donor sodium nitroprusside (SNP), and was strengthened by the superoxide dismutase inhibitor diethyldithiocarbamic acid (DETC) and the nNOS inhibitor N(ω)-propyl-l-arginine hydrochloride (PLA); conversely, there was a smaller CSAR response to PLA or SNP in rats that received a low-fat (12% kcal) diet. Furthermore, PVN pretreatment with the AT1R antagonist losartan or with PEG-SOD, but not SNP, abolished Ang II-induced CSAR enhancement. These findings suggest that obesity alters the PVN O₂⁻ and NO system that modulates CSAR and promotes sympathoexcitation.

High body mass index is a predictor of left ventricular reverse remodelling in heart failure with reduced ejection fraction

AIMS

Structural and functional left ventricular alterations can occur in heart failure (HF), referred to as left ventricular reverse remodelling (LVRR). This study aimed to define novel predictors of LVRR besides well-known effects of medical and device therapy.

METHODS AND RESULTS

From echographic database, we included 295 patients with both left ventricular ejection fraction (LVEF) ≤45% and indexed left ventricular end-diastolic diameter ≥33 mm/m² and who had at least two echocardiographic exams with a delay between 3 and 12 months. LVRR was defined as the combination of (i) normalization of LVEF (LVEF ≥50%) or increase in LVEF ≥10% and (ii) a decrease in indexed left ventricular end-diastolic diameter ≥10%. Clinical follow-up was also obtained. LVRR occurred in 53 (18%) patients. Patients in the LVRR group were more likely to present with de novo HF (75% vs. 42%), had lower LVEF and left ventricular end-diastolic volumes at index examination, yet a higher body mass index (BMI) than non-LVRR patients. Obesity was observed in 25% of LVRR patients vs. 14% in others. In multivariate analyses, BMI (per each 1 kg/m² increase) emerged as a predictor of LVRR: odds ratio 1.10 (95% confidence interval 1.02-1.19) after adjustment to other predictors of LVRR. During a mean follow-up of 37 months, 32% of patients had a major adverse cardiac event; de novo HF, age, and LVEF were associated with major adverse cardiac event.

CONCLUSIONS

We identified significant relationship between high BMI and LVRR. This intriguing novel finding deserves further study.

Body composition phenotypes and obesity paradox

PURPOSE OF REVIEW

The obesity paradox is a highly controversial concept that may be attributed to methodological limitations related to its identification. One of the primary concerns is the use of BMI to define obesity. This index does not differentiate lean versus adipose tissue compartments (i.e. body composition) confounding health consequences for morbidity and mortality, especially in clinical populations. This review will describe the past year's evidence on the obesity paradox phenomenon, primarily focusing on the role of abnormal body composition phenotypes in explaining the controversies observed in the literature.

RECENT FINDINGS

In spite of the substantial number of articles investigating the obesity paradox phenomenon, less than 10% used a direct measure of body composition and when included, it was not fully explored (only adipose tissue compartment evaluated). When lean tissue or muscle mass is taken into account, the general finding is that a high BMI has no protective effect in the presence of low muscle mass and that it is the latter that associates with poor prognosis.

SUMMARY

In view of the body composition variability of patients with identical BMI, it is unreasonable to rely solely on this index to identify obesity. The consequences of a potential insubstantial obesity paradox are mixed messages related to patient-related prognostication.