Does body mass index truly affect mortality and cardiovascular outcomes in patients after coronary revascularization with percutaneous coronary intervention or coronary artery bypass graft? A systematic review and network meta-analysis

Clinical impact of body mass index on outcomes of ischemic and hemorrhagic strokes

BACKGROUND AND AIM

To investigate the prognostic implication of body mass index (BMI) on clinical outcomes after acute ischemic and hemorrhagic stroke.

METHODS

The subjects of the study included adult patients with available baseline body weight and height data who had suffered an acute stroke and were registered in the Japan Stroke Data Bank-a hospital-based, multicenter stroke registration database-between January 2006 and December 2020. The outcome measures included unfavorable outcomes defined as a modified Rankin Scale (mRS) score of 5-6 and favorable outcomes (mRS 0-2) at discharge, and in-hospital mortality. Mixed effects logistic regression analysis was conducted to determine the relationship between BMI categories (underweight, normal weight, overweight, class I obesity, class II obesity; <18.5, 18.5-23.0, 23.0-25.0, 25-30, ⩾30 kg/m2) and the outcomes, after adjustment for covariates.

RESULTS

A total of 56,230 patients were assigned to one of the following groups: ischemic stroke (IS, n = 43,668), intracerebral hemorrhage (ICH, n = 9741), and subarachnoid hemorrhage (SAH, n = 2821). In the IS group, being underweight was associated with an increased likelihood of unfavorable outcomes (odds ratio, 1.47 (95% confidence interval (CI):1.31-1.65)) and in-hospital mortality (1.55 (1.31-1.83)) compared to outcomes in those with normal weight. Being overweight was associated with an increased likelihood of favorable outcomes (1.09 (1.01-1.18)). Similar associations were observed between underweight and these outcomes in specific IS subtypes (cardioembolic stroke, large artery stroke, and small-vessel occlusion). Patients with a BMI ⩾30.0 kg/m2 was associated with an increased likelihood of unfavorable outcomes (1.44 (1.01-2.17)) and in-hospital mortality (2.42 (1.26-4.65)) in large artery stroke. In patients with ICH, but not those with SAH, being underweight was associated with an increased likelihood of unfavorable outcomes (1.41 (1.01-1.99)).

CONCLUSIONS

BMI substantially impacts functional outcomes following IS and ICH. Lower BMI consistently affected post-stroke disability and mortality, while higher BMI values similarly affected these outcomes after large artery stroke.

Body Mass Index and All-Cause Mortality in Elderly Patients with Percutaneous Coronary Intervention: A Meta-Analysis

INTRODUCTION

The "obesity paradox" in elderly patients suffering from percutaneous coronary intervention (PCI) remains a source of controversy. The present meta-analysis focused on exploring the real existence of "obesity paradox" in these patients.

METHODS

As of November 2022, PubMed, Cochrane, and Embase databases were comprehensively searched to identify articles reporting all-cause mortality according to diverse body mass index (BMI) categories after PCI among the old cases developing coronary artery disease (CAD). Summary estimates of relative risks (RRs) were assigned to four BMI groups, including underweight, normal weight, overweight, and obesity groups.

RESULTS

There were altogether nine articles involving 25,798 cases selected for further analysis. Relative to normal weight group, overweight and obesity groups had decreased all-cause mortality (RR: 0.86, 95% CI: 0.77-0.95 for overweight group; RR: 0.57, 95% CI: 0.40-0.80 for obesity group), while underweight group had elevated all-cause mortality (RR: 1.52, 95% CI: 1.01-2.29).

CONCLUSION

Our study revealed an "obesity paradox" relation of BMI with all-cause mortality in elderly cases receiving PCI. In comparison with normal weight group, overweight and obesity groups had decreased all-cause mortality, while underweight group had increased all-cause mortality.

Predictors of Premature Mortality Following Coronary Artery Bypass Grafting: An Iranian Single-Centre Study

Modifiable risk factors play an important role in the premature mortality among patients undergoing coronary artery bypass grafting (CABG). The aim of this study was to examine the factors that influence the early death of patients who had CABG. We conducted a prospective cohort study and followed 2863 patients after their CABG, and collected data on their characteristics and blood tests. We used the Cox proportional hazards regression model in Stata, version 16, to identify the predictors of early mortality. Out of 2863 patients, 162 died during the follow-up period. The survival rate was 99.2% within the first three days after the surgery, 96.2% from the fourth day to the end of the first year, 94.9% at the end of the second year, and 93.6% at the end of the third year. After adjusting for confounding factors, we found that older age (hazard ratio [HR] 1.05, 95% CI 1.02, 1.08 for one year increase in age), obesity (HR 2.16, 95% CI 1.25, 3.72), ejection fraction < 50% (HR 1.61, 95% CI 1.06, 2.44), number of rehospitalizations (HR 2.63, 95% CI 1.35, 5.12 for two or more readmissions), history of stroke (HR 2.91, 95% CI 1.63, 5.21), living in rural areas (HR 1.58, 95% CI 1.06, 2.34), opium use (HR 2.08, 95% CI 1.40, 3.09), and impaired glomerular filtration rate increased the risk of early death after CABG, while taking a beta-blocker (HR 0.59, 95% CI 0.38, 0.91) reduced the risk. We conclude that modifiable risk factors such as excess body mass, high blood glucose, opium use, and kidney dysfunction should be monitored and managed in patients who had CABG to improve their survival outcomes.

Association of N-terminal pro-B-type natriuretic peptide levels and mortality risk in acute myocardial infarction across body mass index categories: an observational cohort study

BACKGROUND

The prognostic value of N-terminal pro-B-type natriuretic peptide (NT-proBNP) across body mass index (BMI) categories in patients with acute myocardial infarction (AMI) is unclear. We aimed to assess the predictive value of NT-proBNP levels and identify the best cutoff values for mortality risk prediction across BMI categories in AMI.

METHODS

We analyzed 4677 patients with AMI from the Cardiovascular Centre Beijing Friendship Hospital Database Bank. Patients were classified into underweight (< 18.5 kg/m2), normal-weight (18.5-23.9 kg/m2), overweight (24-27.9 kg/m2), and obese (≥ 28 kg/m2) groups. The association between NT-proBNP (ln-transformed) and mortality was investigated using Cox regression and stratified by BMI.

RESULTS

During follow-up (13,787 person-years of observation), 718 patients died, averaging 52.1 events per 1000 person-years. NT-proBNP levels were inversely correlated with BMI (β = - 0.096, P < 0.001). After adjustment, NT-proBNP was independently associated with all-cause mortality (hazard ratio [HR] per 1-SD: 1.82; 95% confidence interval [CI] 1.60-2.07) in patients with AMI. Similar findings were observed in analyses stratified by BMI category, except for the underweight group. Adding NT-proBNP to conventional risk models improved risk discrimination in normal-weight, overweight, and obese patients (C-index changes of 0.036, 0.042, and 0.032, respectively) and classification of patients into predicted mortality risk categories (net reclassification improvement 0.263, 0.204, and 0.197, respectively). The best NT-proBNP cutoff values for 5-year mortality risk prediction across BMI categories were 5710, 4492, 2253, and 1300 pg/ml.

CONCLUSION

NT-proBNP level was an independent prognostic factor for mortality in patients with AMI and varied according to BMI. The best NT-proBNP cutoff values for mortality risk prediction reduced as BMI increased.

Mortality, Cardiovascular, and Medication Outcomes in Patients With Myocardial Infarction and Underweight in a Meta-Analysis of 6.3 Million Patients

Although most of the current evidence on myocardial infarction focuses on obesity, there is growing evidence that patients who are underweight have unfavorable prognosis. This study aimed to explore the prevalence, clinical characteristics, and prognosis of this population at risk. Embase and Medline were searched for studies reporting outcomes in populations who were underweight with myocardial infarction. Underweight and normal weight were defined according to the World Health Organization criteria. A single-arm meta-analysis of proportions was used to estimate the prevalence of underweight in patients with myocardial infarction, whereas a meta-analysis of proportions was used to estimate the odds ratio of all-cause mortality, medications prescribed, and cardiovascular outcomes. Twenty-one studies involving 6,368,225 patients were included, of whom 47,866 were underweight. The prevalence of underweight in patients with myocardial infarction was 2.96% (95% confidence interval 1.96% to 4.47%). Despite having fewer classical cardiovascular risk factors, patients who were underweight had 66% greater hazard for mortality (hazard ratio 1.66, 95% confidence interval 1.44 to 1.92, p <0.0001). The mortality of patients who were underweight increased from 14.1% at 30 days to 52.6% at 5 years. Nevertheless, they were less likely to receive guideline-directed medical therapy. Relative to subjects with normal weight, Asian populations who were underweight had greater mortality risks than those of their Caucasian counterparts (p = 0.0062). In conclusion, in patients with myocardial infarction, those who were underweight tend to have poorer prognostic outcomes. A lower body mass index is an independent predictor of mortality, which calls for global efforts in addressing this modifiable risk factor in clinical practice guidelines.

Ranking of cardiovascular risk factors in Romania- regional epidemiological approach

An extensive epidemiological investigation was applied regarding the risk factors, to a cohort of patients with pre-existing heart disease, hospitalized for tertiary prophylaxis in a rehabilitation hospital. The group of 499 patients from all regions of the country respected the proportions of gender and environment of origin for the general population of Romania and was adjusted according to regional proportions. The ranking of risk factors and protection factors present in the studied population was made, at the level of each of the 8 regions of the country and for the whole country consolidated. The profile of the cardiovascular patient was identified. We used risk factors for population characterization, not for aggregation into tools for assessing total cardiovascular risk (as is the trend in large cohort studies since Framingham) The data processing was done to be able to develop prevention strategies in the interest of the specific individual, not to standardize population characteristics and translate them to the individual thus decreasing their appropriateness. Keywords: 1 cardiovascular risk-factors, 2 cardiovascular diseases prevention , 3 cardiovascular rehabilitation.

The association between different body mass index levels and midterm surgical revascularization outcomes

Background

There are conflicting results regarding the relationship between overweight/obesity and the outcomes of coronary artery bypass graft surgery (CABG), termed “the obesity paradox”. This study aimed to evaluate the effects of body mass index (BMI) on the midterm outcomes of CABG.

Methods

This historical cohort study included all patients who underwent isolated CABG at our center between 2007 and 2016. The patients were divided into five categories based on their preoperative BMIs (kg/m²): 18.5≤BMI<25, 25≤BMI<30, 30≤BMI<35, 35≤BMI<40, and BMI≥40. Patients with BMIs below 18.5 kg/m² were excluded. The endpoints of this study were all-cause mortality and major adverse cardio-cerebrovascular events (MACCEs), comprising acute coronary syndromes, cerebrovascular accidents, and all-cause mortality at five years. For the assessment of the linearity of the relationship between continuous BMI and the outcomes, plots for time varying hazard ratio of BMI with outcomes were provided.

Results

Of 17 751 patients (BMI = 27.30 ±4.17 kg/m²) who underwent isolated CABG at our center, 17 602 patients (mean age = 61.16±9.47 y, 75.4% male) were included in this study. Multivariable analysis demonstrated that patients with pre-obesity and normal weight had similar outcomes, whereas patients with preoperative BMIs exceeding 30 kg/m² kg/m² had a significantly higher risk of 5-year all-cause mortality and 5-year MACCEs than those with pre-obesity. Additionally, a positive association existed between obesity degree and all-cause mortality and MACCEs. Further, BMIs of 40 kg/m² or higher showed a trend toward higher MACCE risks (adjusted hazard ratio, 1.32; 95% confidence interval, 0.89 to 1.95), possibly due to the small sample size. A nonlinear, albeit negligible, association was also found between continuous BMI and the study endpoints.

Conclusions

Our findings suggest that preoperative obesity (BMI>30 kg/m²) in patients who survive early after CABG is associated with an increased risk of 5-year all-cause mortality and 5-year MACCEs. These findings indicate that physicians and cardiac surgeons should encourage patients with high BMIs to reduce weight for risk modification.

Pathogenesis, Murine Models, and Clinical Implications of Metabolically Healthy Obesity

Although obesity is commonly associated with numerous cardiometabolic pathologies, some people with obesity are resistant to detrimental effects of excess body fat, which constitutes a condition called “metabolically healthy obesity” (MHO). Metabolic features of MHO that distinguish it from metabolically unhealthy obesity (MUO) include differences in the fat distribution, adipokine types, and levels of chronic inflammation. Murine models are available that mimic the phenotype of human MHO, with increased adiposity but preserved insulin sensitivity. Clinically, there is no established definition of MHO yet. Despite the lack of a uniform definition, most studies describe MHO as a particular case of obesity with no or only one metabolic syndrome components and lower levels of insulin resistance or inflammatory markers. Another clinical viewpoint is the dynamic and changing nature of MHO, which substantially impacts the clinical outcome. In this review, we explore the pathophysiology and some murine models of MHO. The definition, variability, and clinical implications of the MHO phenotype are also discussed. Understanding the characteristics that differentiate people with MHO from those with MUO can lead to new insights into the mechanisms behind obesity-related metabolic derangements and diseases.

Associations of body mass index with mortality in heart failure with preserved ejection fraction patients with ischemic versus non-ischemic etiology

Background

Obesity could paradoxically improve prognosis in patients with heart failure (HF), termed the “obesity paradox.” Whether HF etiology could modify the “obesity paradox” is still controversial. In the present study, we aimed to assess the relationship between obesity and death in patients with heart failure with preserved ejection fraction (HFpEF) with non-ischemic versus ischemic etiologies.

Methods

We analyzed 3,360 HFpEF patients from the TOPCAT (Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist) trial. Cox regression models were used to assess the association of obesity assessed by body mass index (BMI) with short-term and long-term death risk.

Results

Overweight and obesity were associated with a lower risk of long-term all-cause death in patients with non-ischemic HFpEF, even in those with class III obesity (adjusted HR: 0.61, 95% CI 0.38–0.97). However, in the ischemic subgroup, as obesity advanced, this paradoxical relationship was gradually attenuated and disappeared in class III obesity (adjusted HR: 0.93, 95% CI 0.56–1.57). Restricted cubic spline analyses confirmed the differential relationship of baseline BMI with risk of long-term death with a BMI higher than 30 kg/m2 in non-ischemic versus ischemic HFpEF. In the short-term follow-up, the beneficial effects of overweight and obesity on survival were consistently observed in all the BMI categories, with the nadirs of all-cause death risk at class III obesity category both in non-ischemic and ischemic subgroups.

Conclusion

“Obesity paradox” was evident both in non-ischemic and ischemic HFpEF during short-term follow-up, even in those with class III obesity. However, the beneficial effect of class III obesity disappeared during long-term follow-up in ischemic HFpEF.

Clinical Trial Registration

[https://clinicaltrials.gov], identifier [NCT00094302].

The waist-to-body mass index ratio as an anthropometric predictor for cardiovascular outcome in subjects with established atherosclerotic cardiovascular disease

Obesity is an independent risk factor for atherosclerotic cardiovascular disease (ASCVD). However, ‘obesity paradox’ is observed in patients with coronary artery disease while defining obesity by body mass index (BMI). The purpose of this study is to identify a better anthropometric parameter to predict cardiovascular events in patients with ASCVD. The study was conducted using the Taiwanese Secondary Prevention for patients with AtheRosCLErotic disease (T-SPARCLE) Registry. A total of 6,920 adult patients with stable ASCVD, enrolled from January 2010 to November 2014, were included, with a mean age of 65.9 years, 73.9% males, and a mean BMI of 26.3 kg/m² at baseline. These patients were followed up for a median of 2.5 years. The study endpoint was the composite major adverse cardiovascular event (MACE), defined as cardiovascular death, nonfatal myocardial infarction or stroke, or cardiac arrest with resuscitation. Multivariable Cox proportional hazards regression showed a significant positive association between waist-to-BMI ratio and MACE (adjusted hazard ratio 1.69 per cm‧m²/kg increase in waist-to-BMI ratio, 95% CI 1.12–2.49, p = 0.01) after adjusting for potential risk factors and confounders. Traditional anthropometric parameters, such as BMI, weight, waist and waist-hip ratio, or newer waist-based indices, such as body roundness index and a body shape index, did not show any significant linear associations (p = 0.09, 0.30, 0.89, 0.54, 0.79 and 0.06, respectively). In the restricted cubic spline regression analysis, the positive dose–response association between waist-to-BMI ratio and MACE persisted across all the range of waist-to-BMI ratio. The positive dose–response association was non-linear with a much steeper increase in the risk of MACE for waist-to-BMI ratio > 3.6 cm‧m²/kg. In conclusion, waist-to-BMI ratio may function as a positive predictor for the risk of MACE in established ASCVD patients.

Body Mass Index and Long-Term Follow-Up Outcomes in Patients With Acute Myocardial Infarction by the Median of Non-HDL Cholesterol: Results From an Observational Cohort Study in China

Background: The association between obesity, non-HDL cholesterol, and clinical outcomes in subjects with acute myocardial infarction (AMI) undergoing percutaneous coronary intervention (PCI) is incompletely understood. The aim of this investigation was to explore the association between body mass index (BMI), non-high density lipoprotein (non-HDL) cholesterol, and long-term follow-up prognosis.

Methods: This present study used data obtained by the Cardiovascular Center of Beijing Friendship Hospital Database Bank. We identified 3,780 consecutive AMI populations aged 25–93 years from 2013 to 2020. Participants were categorized as normal weight (18.5 ≤ BMI <22.9 kg/m²), overweight (23.0 ≤ BMI <24.9 kg/m²), obese class I (25.0 ≤ BMI <29.9 kg/m²), and obese class II (BMI ≥ 30.0 kg/m²). The endpoint of interest was cardiovascular (CV) death, all-cause death, myocardial infarction (MI), stroke, unplanned revascularization, and cardiac hospitalization.

Results:Participants with higher BMI were younger and more likely to be males compared with lower BMI groups. Elevated non-HDL cholesterol was present in 8.7, 11.0, 24.3, and 5.9% of the normal, overweight, obese class I, and obese class II groups, respectively. After multivariate adjustment, compared to normal-weight participants with decreased non-HDL cholesterol (reference group), obese participants with and without elevated non-HDL cholesterol had a lower risk of mortality (with obese class I and elevated non-HDL cholesterol: hazard ratio [HR] 0.44, 95% confidence interval [CI] 0.28–0.67; with obese class I and decreased non-HDL cholesterol: HR, 0.68, 95% CI, 0.47–0.98; with obese class II and elevated non-HDL cholesterol: HR, 0.42, 95% CI, 0.20–0.87; with obese class II and decreased non-HDL cholesterol: HR, 0.35, 95% CI, 0.16–0.72).

Conclusion: In AMI participants performing with PCI, obesity had a better long-term prognosis which probably unaffected by the level of non-HDL cholesterol.

Developing and verifying a multivariate model to predict the survival probability after coronary artery bypass grafting in patients with coronary atherosclerosis based on the MIMIC-III database

BACKGROUND

Coronary atherosclerosis is one of the main cardiovascular diseases affecting the global population. Coronary artery bypass grafting (CABG) is commonly used to improve the survival probability of patients with coronary atherosclerosis. However, the prognosis of patients after CABG remains unclear.

OBJECTIVES

We aimed to construct a novel nomogram comprising readily available indicators to predict the 1-, 2-, and 3-year survival rates after CABG in patients with coronary atherosclerosis.

METHODS

We utilized the Medical Information Mart for Intensive Care III (MIMIC-III) database for the study. The calibration plot, concordance index (C-index), net reclassification index (NRI), integrated discrimination improvement (IDI), and area under the receiver operating characteristic curve (AUROC) were used to evaluate the performance of the model, and to compare the nomogram with the Sequential Organ Failure Assessment (SOFA) score and Simplified Acute Physiology Score II (SAPS II) in order to illustrate the clinical effectiveness of the model.

RESULTS

The multivariate Cox regression model showed that age, marital status, body mass index, creatinine, platelet count, red cell distribution width, heart rate, intensive-care unit stay time, and Elixhauser Comorbidity Index were risk factors. The C-indexes of the nomogram exceeded 0.75, and its NRI and IDI were both higher than 0. The AUROCs were larger for the nomogram than for the SAPS II and SOFA score.

CONCLUSION

Our new nomogram is a personalized tool that helps clinicians choose treatment options and predict the long-term prognosis of patients.

Serum uric acid is associated with incident metabolic syndrome independent of body shape index and body roundness index in healthy individuals

BACKGROUND AND AIMS

Elevated serum uric acid (SUA) levels, body shape index (BSI) and body roundness index (BRI) were associated with incident metabolic syndrome (MetS). We aimed to investigate the relationship among the SUA level, BSI, and BRI on the incidence of MetS.

METHODS AND RESULTS

We retrospectively included 6221 healthy individuals from annual health exams at our hospital between 2016/1/1 and 2016/12/31. We defined hyperuricemia as SUA levels greater than 7 mg/dl in men and 6 mg/dl in women and MetS according to the contemporary definition. The study cohort included 6221 healthy individuals with an overall incidence rate of MetS of 9.8%. Compared with the normouricemic group, the hyperuricemic group had a greater incidence of MetS (17.2% vs. 9.6%, P < 0.001). After full adjustment for confounders, the SUA level was significantly associated with incident MetS in addition to body mass index (BMI) (adjusted OR [aOR]: 1.161, 95% CI: 1.071-1.259, P < 0.001), BRI (aOR: 1.196, 95% CI: 1.104-1.296, P < 0.001), and BSI (aOR: 1.297, 95% CI: 1.200-1.403, P < 0.001). Regarding the anthropometric indices, BMI and BRI were independent predictors of incident MetS, but the BSI lost its significant association in multivariate logistic regression analyses. In sensitivity analyses, various thresholds of elevated SUA levels remained associated with incident MetS.

CONCLUSION

We showed a dose-response effect of SUA on incident MetS independent of BMI, BRI and BSI in healthy individuals. Future studies can use SUA levels to stratify cardiometabolic risk in healthy individuals.

CLINICAL TRIALS

ClinicalTrials.gov with the identification number NCT03473951.

Association of Body Mass Index with Mortality in Patients with Cardiogenic Shock following Acute Myocardial Infarction: A Contemporary Danish Cohort Analysis

AIMS

The obesity paradox suggests a better prognosis in overweight or obese patients with heart failure and acute myocardial infarction (AMI) than patients with normal weight. Few studies have investigated the association between BMI and mortality in patients with AMI complicated by cardiogenic shock (AMICS). The aim of this study was to evaluate the association between BMI and 30-day mortality in patients with AMICS.

METHODS AND RESULTS

A retrospective study of 1,716 patients with AMICS treated at 2 tertiary centers in south-eastern Denmark between 2010 and 2017. Patients undergoing revascularization and who were admitted to the intensive care unit were included (n = 1,216). BMI was available in 1,017 patients (83.6%). Patients were divided according to the WHO classification as normal weight BMI <24.9 kg/m2 (n = 453), overweight BMI 25-29.9 kg/m2 (n = 391), obese class 1 BMI 30-34.9 kg/m2 (n = 131), and obese class 2 + 3 BMI >35 kg/m2 (n = 42). Differences in baseline characteristics, in-hospital treatment, and the primary outcome of all-cause mortality at 30 days were examined. Obese patients had more comorbidities such as diabetes, hypertension, and dyslipidemia than patients with normal weight. Need for renal replacement therapy was higher among obese patients (normal weight, 19% vs. obese class 2 + 3, 35%, p = 0.02); otherwise, no difference in management was found. No difference in 30-day mortality was observed between groups (normal weight 44%, overweight 38%, obese class 1 41%, and obese class 2 + 3 45% at 30 days; ns).

CONCLUSIONS

Thirty-day mortality in patients with AMICS was not associated with the BMI category. Thus, evidence of an "obesity paradox" was not observed in this contemporary cohort of patients with AMICS in Denmark.

Obesity and Cardiovascular Disease: A Scientific Statement From the American Heart Association

The global obesity epidemic is well established, with increases in obesity prevalence for most countries since the 1980s. Obesity contributes directly to incident cardiovascular risk factors, including dyslipidemia, type 2 diabetes, hypertension, and sleep disorders. Obesity also leads to the development of cardiovascular disease and cardiovascular disease mortality independently of other cardiovascular risk factors. More recent data highlight abdominal obesity, as determined by waist circumference, as a cardiovascular disease risk marker that is independent of body mass index. There have also been significant advances in imaging modalities for characterizing body composition, including visceral adiposity. Studies that quantify fat depots, including ectopic fat, support excess visceral adiposity as an independent indicator of poor cardiovascular outcomes. Lifestyle modification and subsequent weight loss improve both metabolic syndrome and associated systemic inflammation and endothelial dysfunction. However, clinical trials of medical weight loss have not demonstrated a reduction in coronary artery disease rates. In contrast, prospective studies comparing patients undergoing bariatric surgery with nonsurgical patients with obesity have shown reduced coronary artery disease risk with surgery. In this statement, we summarize the impact of obesity on the diagnosis, clinical management, and outcomes of atherosclerotic cardiovascular disease, heart failure, and arrhythmias, especially sudden cardiac death and atrial fibrillation. In particular, we examine the influence of obesity on noninvasive and invasive diagnostic procedures for coronary artery disease. Moreover, we review the impact of obesity on cardiac function and outcomes related to heart failure with reduced and preserved ejection fraction. Finally, we describe the effects of lifestyle and surgical weight loss interventions on outcomes related to coronary artery disease, heart failure, and atrial fibrillation.

Association of body mass index with in-hospital major adverse outcomes in acute type A aortic dissection patients in Fujian Province, China: a retrospective study

Background

Abnormal body mass index (BMI) has been related to a higher risk of adverse outcomes in patients undergoing cardiac surgery. However, the effects of BMI in patients with acute type A aortic dissection (AAAD) on postoperative outcomes remain unclear. This study aimed to explore the relationships between BMI and in-hospital major adverse outcomes (MAO) in AAAD patients.

Methods

Patients who underwent AAAD surgery at Cardiac Medical Center of Fujian Province from June 2013 to March 2020 were retrospectively evaluated. They were divided into three groups on the basis of Chinese BMI classification established by the World Health Organization: normal weight group (BMI 18.5–23.9 kg/m²), overweight group (BMI 24–27.9 kg/m²), and obese group (BMI >28 kg/m²). Patients’ baseline characteristics, preoperative, operative, and postoperative data were collected. A multivariable logistic regression analysis model was performed to identify the association between BMI and MAO in AAAD patients.

Results

Of 777 cases, 31.9% were normal weight, 52.5% were overweight, and 15.6% were obese. A total of 160(20.6%) patients died in-hospital. There was a significant difference between the three groups for MAO (62.9% vs 72.1% vs 77.7%, respectively, P = 0.006). The incidence of postoperative complications did not differ among the three groups, except for postoperative bleeding, and prolonged mechanical ventilation, the proportion of which were higher in the overweight and obese groups. Besides, multivariable logistic regression analysis demonstrated that a higher risk of MAO in the overweight [odds ratios (ORs):1.475, 95%CI:1.006–2.162], and obese patients (ORs:2.147, 95%CI:1.219–3.782) with reference to the normal weight patients, and age, white blood cell, prior stroke and cardiopulmonary bypass time were also associated with in-hospital MAO (P<0.05).

Conclusions

BMI is independently associated with higher in-hospital MAO in patients who underwent AAAD surgery.

Stroke Rates Following Surgical Versus Percutaneous Revascularization for Ischemic Heart Disease

PURPOSE OF REVIEW

Coronary revascularization is a commonly performed major procedure in the hospitals. Stroke is one of the dreaded complications after coronary revascularization procedures. The focus of this review is to understand the stroke risk in percutaneous cutaneous intervention (PCI) and coronary artery bypass grafting (CABG) procedures.

RECENT FINDINGS

Available data show that PCI offers less procedural stroke risk compared to CABG although the survival benefits of CABG are better in certain scenarios. Innovative advancements in techniques, pre-procedural optimum medical therapy (OMT), intraoperative neuro-monitoring, and multidisciplinary post procedural care are the few strategies in early detection and reduce stroke risk. Despite several innovations and strategies, it is evident that there is not enough data available to make concrete conclusions related to stroke risk after coronary revascularization, which warrants further investigation.

Inconsistencies in study eligibility criteria are common between non-Cochrane systematic reviews and their protocols registered in PROSPERO

The author should give careful consideration to the study eligibility criteria of systematic reviews (SRs) and follow it after review protocol development to reduce the possibility of manipulation of inclusion. Our aim was to investigate the prevalence of differences in study eligibility criteria between non-Cochrane SRs and their pre-registered protocols on PROSPERO, and determined what changes were involved as well as whether those changes were explained. We searched the protocols registered on PROSPERO platform in the year of 2018 and then selected these protocols which full-text have been published up to June 9, 2020. A random sample (n = 100) was included. Published full-texts were identified through the protocol's final publication citation. The following five key components of study eligibility criteria were compared: participants, intervention(s)/exposure(s), comparator(s), types of study design, and outcome(s). A total of 90% of included SRs exhibited differences in study eligibility criteria, and 59/90 altered in no less than two key components. Only one SR reported and explained the rationale for changes to the individual key component (the definition of exposure). The "Outcome(s)" exhibited the greatest variation, with changes in 61% of the SRs. The "Comparator(s)/control" exhibited the smallest variation, with changes in 20% of the SRs. Differences in study eligibility criteria between the non-Cochrane SRs and their protocols registered on PROSPERO were widespread but were seldom explained. Authors themselves, PROSPERO platform, as well as peer-review journals and their peer-reviewers should play a role in further improving transparency.

Body mass index and all-cause mortality in patients with percutaneous coronary intervention: A dose-response meta-analysis of obesity paradox

The association between body mass index (BMI) and mortality of patients with percutaneous coronary intervention (PCI) is still controversial. We hope to explore whether the 'obesity paradox' really exists through this dose-response meta-analysis. PubMed, Embase and Cochrane databases were systematically searched for eligible studies up to April 2020. The random-effects restricted cubic spline models were used to evaluate the potential non-linear relationship between BMI and all-cause mortality of patients undergoing PCI. Fifteen studies were identified and included total 138 592 participants. The pooled hazard ratio of all-cause mortality was 0.60 (95% confidence interval: 0.45-0.82) when compared the highest category (mean = 33.32 kg m^-2 ) of BMI with the lowest category (mean = 18.89 kg m^-2 ). A non-linear U-shaped dose-response curve between BMI and the risk of all-cause mortality was found, with higher mortality rate at BMI lower than 27 kg m^-2 and higher than 32 kg m^-2 . The 'obesity paradox' does exist after PCI. The association between BMI and the risk of all-cause mortality for patients undergoing PCI is U shaped, with a nadir of risk at a BMI of 27 to 32 kg m^-2 and the highest risk at patients with underweight. The relationship between other prognostic indicators and BMI is worthy of further research.

Does the anthropometric profile influence infection morbidity after coronary artery bypass grafting?

BACKGROUND

Infection after cardiovascular surgery is multifactorial. We sought to determine whether the anthropometric profile influences the occurrence of infection after isolated coronary artery bypass grafting (CABG).

METHODS

Between January 2011 and June 2016, 1777 consecutive adult patients were submitted to isolated coronary artery bypass grafting. Mean age was 61.7 ± 9.8 years and 1193 (67.1%) were males. Patients were divided into four groups according to the body mass index (BMI) classification: underweight (BMI < 18.5 kg/m² ; N = 17, 0.9%), normal range (BMI: 18.5-24.99 kg/m² ; N = 522, 29.4%), overweight (BMI: 25-29.99 kg/m² ; N = 796, 44.8%), and obese (BMI > 30 kg/m² ; N = 430, 24.2%). In-hospital outcomes were compared and independent predictors of infection were obtained through multiple Poisson regression with a robust variation.

RESULTS

Independent predictors of any infection morbidity were female sex (relative ratio [RR], 1.47; p = .002), age > 60 years (RR, 1.85; p < .0001), cardiopulmonary bypass > 120 min (RR, 1.89; p = .0007), preoperative myocardial infarction < 30 days (RR, 1.37; p = .01), diabetes mellitus (RR, 1.59; p = .0003), ejection fraction < 48% (RR, 2.12; p < .0001), and blood transfusion (RR, 1.55; p = .0008). Among other variables, obesity, as well as diabetes mellitus, were independent predictors of superficial and deep sternal wound infection.

CONCLUSIONS

Other factors rather than the anthropometric profile are more important in determining the occurrence of any infection after CABG. However, surgical site infection has occurred more frequently in obese patients. Appropriate patient selection, control of modifiable factors, and application of surgical bundles would minimize this important complication.

Serum uric acid and incident atrial fibrillation: A systematic review and dose-response meta-analysis

The exposure-effect association between serum uric acid and atrial fibrillationis not well known. We conduct a meta-analysis to quantitatively examine the exposure-effect relationship between serum uric acid and atrial fibrillation. Prospective studies (including cohort or nested case-control) that reported the serum uric acid and atrial fibrillation were identified through electronic searches using EMBASE, PubMed, and the Cochrane Library database. The exposure-effect analysis was performed using a stage robust error meta-regression. Eleven studies were included, with a total of 6831 cases of atrial fibrillation among 527 908 individuals. Both the highest (risk ratio (RR), 1.9; 95% confidence interval (CI), 1.64-2.23; I²  = 0%) and intermediate (RR, 1.36; 95% CI, 1.16-1.59; I²  = 36%) level of serum uric acid were associated with increased risks of atrial fibrillation compared to the patients with the lowest level of serum uric acid. In the exposure-effect analysis, for each 1 mg/dL increase in serum uric acid level, the incidence of atrial fibrillation increased by 21% (RR, 1.21; 95% CI, 1.12-1.32; I²  = 78%). Furthermore, a significant positive linear relationship between serum uric acid and the risk of atrial fibrillation, P_nonlinearity  = 0.47 was found. The exposure-effect analysis demonstrated that serum uric acid over 5.0 mg/dL significantly increased the risk of atrial fibrillation. There was a positive linear association between serum uric acid and risk of atrial fibrillation, both in subjects with noruricaemia and hyperuricaemia. More studies are needed to explore the impact of serum uric acid reduction on the incidence of atrial fibrillation.

Underweight Predicts Greater Risk of Cardiac Mortality Post Acute Myocardial Infarction

Increased body mass index (BMI) is a well-established risk factor for cardiovascular disease; however, patients with elevated BMI, in comparison to those with low BMI, seem to have better survival, a phenomenon reported as "obesity paradox," which remains controversial. We investigated the effect of BMI on cardiac mortality post acute myocardial infarction (AMI).In this analysis, 3562 AMI patients were included and classified into four groups based on BMI values. The primary endpoint was cardiac death. Compared to normoweight group, overweight and obese group subjects were younger, mostly men, and more likely to receive percutaneous coronary intervention (PCI) and had higher levels of glucose and lipids, but lower level of NTproBNP. Subjects in the underweight group were older, were mostly women, had lower Barthel index (BI), were less likely to receive PCI, and had lower levels of glucose and lipids, but higher level of N-terminal pro-brain natriuretic peptide (NTproBNP) and higher rates of left ventricular ejection fraction (LVEF) < 50%. During a median follow-up period of 1.9 years, cardiac death occurred significantly more in the underweight group (30.0%, 10.6%, 7.0%, and 5.0% among the four groups from underweight to obese; P < 0.001 for trend). The Cox analysis revealed that underweight was an independent predictor of subsequent cardiac death (odds ratio (OR), 1.86; 95% confidence interval (CI), 1.07-3.25) and identified that older age, BI < 60, higher levels of cardiac troponin I (cTnI), LVEF < 50%, and not receiving PCI were independently associated with increased risk of cardiac death.Patients who were underweight were at greater risk of cardiac death post AMI. In addition, older age, frail, higher levels of cTnI, LVEF < 50%, and not receiving PCI also independently predicted cardiac mortality post AMI.

Implications of the dynamic nature of metabolic health status and obesity on risk of incident cardiovascular events and mortality: a nationwide population-based cohort study

AIMS

We hypothesized that transitions in metabolic health status and obesity affect the cardiovascular (CV) risk and mortality in population with metabolically healthy obesity (MHO).

METHODS

This study enrolled 514,866 participants from the Korean National Health Insurance Service-National Sample Cohort. Changes in metabolic health status and obesity from the baseline examination in 2009-2010 to the next biannual health examination in 2011-2012 were determined. Study participants were categorized into four groups: (1) metabolically healthy, non-obese (MHNO), defined as BMI < 25 kg/m² and no or one metabolic risk factor; (2) metabolically unhealthy, non-obese (MUNO), defined as BMI < 25 kg/m² and ≥2 metabolic risk factors; (3) MHO, defined as BMI ≥ 25 kg/m² and no or one metabolic risk factor; and (4) metabolically unhealthy, obese (MUO), defined as BMI ≥ 25 kg/m² and ≥2 metabolic risk factors. The study subjects were followed-up from 2011 to 2015 for cardiovascular events, CV mortality and all-cause mortality.

RESULTS

Among the subjects classified as MHO in 2009-2010, 45.6% were classified as MHO in 2011-2012, whereas 11.6%, 6.0%, and 36.8% were classified as MHNO, MUNO, and MUO, respectively. The risk of CV events was higher in baseline MHO group than MHNO group (HR, 1.14; 95% CI, 1.05-1.24). However, in baseline MHO group, CV mortality was not increased (HR, 0.85; 95% CI, 0.69-1.06) and all-cause mortality was even lower than that of MHNO group (HR, 0.86; 95% CI, 0.79-0.93). Compared to the stable MHO subjects, the risk of CV events was significantly higher in the subjects who transitioned from MHO to MUO with multivariate-adjusted HRs of 1.24 (95% CI: 1.00-1.54). When weight loss and progression to metabolic unhealthy phenotype occur simultaneously in the MHO population, the all-cause mortality was increased compared to the stable MHO group (HR, 1.96; 95% CI, 1.45-2.65).

CONCLUSIONS

Subjects with MHO constitute a heterogeneous group. Our finding supports that evolving to a metabolically unhealthy status and losing weight simultaneously is associated with the adverse outcome in the MHO population.

Weight reduction and cardiovascular benefits: Protocol for a systematic review and meta-analysis

BACKGROUND

There is widespread obesity paradox in cardiovascular diseases, the cardiovascular influence from weight management remains controversial. Moreover, previous publications indicating that different weight reduction extent might lead to various results. Thus, it is of importance to reassess the cardiovascular benefits of weight management strategies.

OBJECTIVES

This review is designed to assess the association between weight loss and cardiovascular outcomes.

METHODS

Clinical trials including randomized control trials, observational studies reported a weight change before and after weight interventions including lifestyle intervention, as well as pharmacotherapies were included. Three major databases will be searched to retrieve the appropriate studies. Dual selection and abstraction of data will be conducted by 2 authors independently. The population, intervention, comparator, outcomes, study characteristics framework will be used to extract all the necessary data from included studies. The risk of bias assessment will be conducted in duplicate based on the Cochrane risk of bias guideline for randomized controlled trials (RCTs) and the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement for observational studies respectively. The primary outcomes will be the cardiovascular mortality, and the secondary outcomes are all-cause mortality and new cardiovascular events. A meta-analysis will be considered if there is sufficient homogeneity among selected studies. Follow the criteria of Grading of Recommendations, Assessment, Development and Evaluation (GRADE), the quality of the cumulative evidence will be evaluated.

RESULTS AND CONCLUSIONS

The results of this systematic review could provide reliable and concrete evidence for weight loss and its cardiovascular benefits.Prospero registration number: CRD42018108582.