Association of Obesity With In-Hospital Mortality of Cardiogenic Shock Complicating Acute Myocardial Infarction

Impact of Age, Gender, and Body Mass Index on Short-Term Outcomes of Patients With Cardiogenic Shock on Mechanical Circulatory Support

This single-center, observational study assessed the impact of age, gender, and body mass index (BMI) in patients with cardiogenic shock (CS) on temporary mechanical circulatory support. All adult patients admitted to the Cleveland Clinic main campus Cardiac Intensive Care Unit (CICU) between December 1, 2015, to December 31, 2019, CICU with CS necessitating mechanical circulatory support (MCS) with intra-aortic balloon pump, Impella, or venous arterial-extra corporeal membrane oxygenation were retrospectively analyzed for this study. Baseline characteristics and 30-day outcomes were collected through physician-directed chart review. The impact of age, gender, and BMI on 30-day mortality was assessed using multivariable logistic regression. Kaplan-Meier survival curves were used to analyze the survival difference in specific subsets. A total of 393 patients with CS on temporary MCS were admitted to our CICU during the study period. The median age of our cohort was 63 years (interquartile range 54 to 70 years), median BMI was 28.50 kg/m2 (interquartile range 24.62 to 29.72) and 70% (n = 276) were men. In total, 22 patients >80 years had received MCS compared with 372 patients <80 years. Patients >80 years on MCS had significantly higher 30-day mortality compared with those <80 years (81.8% vs 49.3%, p = 0.006). Upon stratifying patients by BMI, 161 (41%) patients were found to have BMI ≥30 kg/m2 whereas 232 (59%) patients had BMI <30 kg/m2. Comparison of 30-day mortality revealed that patients with BMI ≥30 did significantly worse than patients with BMI <30 (59.6% vs 45.3%, p = 0.007). There was no difference in 30-day mortality between men and women. On multivariable logistic regression, both age and BMI had a positive linear relation with adjusted 30-day mortality whereas gender did not have a major effect. Advanced age and higher BMI are independently associated with worse outcomes in patients with CS on MCS. Utilizing a strict selection criterion for patients in CS is pertinent to derive the maximum benefit from advanced mechanical support.

Association of body mass index with 30-day all-cause mortality in cardiogenic shock

BACKGROUND AND AIMS

This study investigates the prognostic impact of body mass index (BMI) on the risk of 30-day all-cause mortality in patients with cardiogenic shock (CS). Due to ongoing epidemiological developments, the characteristics of patients with cardiovascular disease are consistently changing. Especially increasing rates of obesity and associated comorbidities have been observed. However, data regarding the prognostic value of BMI in patients with CS remains inconclusive.

METHODS AND RESULTS

Consecutive patients with CS were included from 2019 to 2021. The prognostic value of BMI (i.e., BMI 18.5-<25; 25-30 and >30 kg/m2) was analyzed using Kaplan-Meier and multivariable Cox proportional regression analyses regarding the primary endpoint of 30-day all-cause mortality. Additional risk stratification was performed based on the presence or absence of CS related to acute myocardial infarction (AMI). 256 patients with a median BMI of 26.4 kg/m2 were included. The overall risk of 30-day all-cause mortality was 53.5%. Within the entire study cohort, BMI was not associated with the risk of 30-day all-cause mortality (log rank p ≥ 0.107). In contrast, BMI >30 kg/m2 was associated with higher risk of 30-day all-cause mortality when compared to BMI <25 kg/m2 in patients with AMI-CS (78% vs 47%; log rank p = 0.017), which was confirmed after multivariable adjustment (HR = 2.466; 95% CI 1.126-5.399; p = 0.024). However, BMI was not associated with mortality in patients with non-AMI-CS.

CONCLUSION

BMI >30 kg/m2 was associated with increased risk of 30-day all-cause mortality in patients with AMI-CS, but not in non-AMI-CS.

Obesity and Extracorporeal Membrane Oxygenation (ECMO): Analysis of Outcomes

Traditionally, patients with obesity have been deemed ineligible for extracorporeal life support (ELS) therapies such as extracorporeal membrane oxygenation (ECMO), given the association of obesity with chronic health conditions that contribute to increased morbidity and mortality. Nevertheless, a growing body of literature suggests the feasibility, efficacy, and safety of ECMO in the obese population. This review provides an in-depth analysis of the current literature assessing the effects of obesity on outcomes among patients supported with ECMO (venovenous [VV] ECMO in noncoronavirus disease 2019 and coronavirus disease 2019 acute respiratory distress syndrome, venoarterial [VA] ECMO, and combined VV and VA ECMO), offer a possible explanation of the current findings on the basis of the obesity paradox phenomenon, provides a framework for future studies addressing the use of ELS therapies in the obese patient population, and provides guidance from the literature for many of the challenges related to initiating, maintaining, and weaning ELS therapy in patients with obesity.

Correlation between severity of obesity and mortality in cardiogenic shock

INTRODUCTION

Cardiogenic shock (CS) is associated with high mortality despite the development of risk stratification tools and new treatment strategies. Obesity, although a risk factor for cardiovascular disease, is not included in current risk stratification tools for CS. A relationship between mortality and obesity has only been shown in subsets populations of CS; there is not yet a clear relationship between severity of obesity and all-cause CS.

OBJECTIVES

In this study we evaluate the relationship between rising body mass index (BMI) and mortality in all-cause CS.

METHODS

All patients with BMI measurements and hospitalizations complicated by CS from 2014 to 2019 at a single quaternary care institution were identified. Patients were grouped by obesity classification. Multivariate logistic regression was performed to determine a relationship between higher obesity classifications with 30-day mortality in patients with CS.

RESULTS

Seventy-two patients were available for analysis. Mean BMI for those who survived compared to those who did not was 29.7 ± 8 kg/m2 vs 33.7 ± 7.6 kg/m2 (p = 0.04). The odds ratio for mortality with incremental increase in obesity classification was 1.6 (95% CI 1.1 - 2.6, p = 0.03) after adjusting for etiology of CS and other common associations with CS mortality.

CONCLUSION

This study suggests that the higher mortality risk with incremental increases in BMI should be taken into account when risk stratifying these patients.

Body mass index and outcomes of patients with cardiogenic shock: A systematic review and meta-analysis

BACKGROUND

Cardiogenic shock continues to be a highly morbid complication that affects around 7%-10% of patients with acute myocardial infarction or heart failure. Similarly, obesity has become a worldwide epidemic.

AIM

To analyze the impact of higher body mass index (BMI) on outcomes of patients with cardiogenic shock.

METHODS

A systematic and comprehensive search was undertaken on the electronic databases of PubMed, Embase, ScienceDirect, CENTRAL, and Google Scholar for all types of studies comparing mortality outcomes of patients with cardiogenic shock based on BMI. All studies defined overweight or obese patients based on the World Health Organization BMI criteria. The data were then extracted and assessed on the basis of the Reference Citation Analysis (https://www.referencecitationanalysis.com/).

RESULTS

Five studies were included. On pooled analysis of multivariable-adjusted ratios, we noted a statistically significantly reduced risk of mortality in overweight/ obese vs normal patients (three studies; odds ratio [OR] = 0.92, 95% confidence interval [CI]: 0.85-0.98, I² = 85%). On meta-analysis, we noted that crude mortality rates did not significantly differ between overweight/obese and normal patients after cardiogenic shock (OR = 0.95, 95%CI: 0.79-1.15, I² = 99%). The results were not stable on sensitivity analysis and were associated with substantial heterogeneity.

CONCLUSION

Current evidence on the association between overweight/obesity and mortality after cardiogenic shock is scarce and conflicting. The obesity paradox might exist in patients with cardiogenic shock but could be confounded by the use of mechanical circulatory support. There is a need for further studies to clarify this relationship.

Impact of the Obesity Paradox Between Sexes on In-Hospital Mortality in Cardiogenic Shock: A Retrospective Cohort Study

Background

Several studies have shown that obesity is associated with better outcomes in patients with cardiogenic shock (CS). Although this phenomenon, the “obesity paradox,” reportedly manifests differently based on sex in other disease entities, it has not yet been investigated in patients with CS.

Methods and Results

A total of 1227 patients with CS from the RESCUE (Retrospective and Prospective Observational Study to Investigate Clinical Outcomes and Efficacy of Left Ventricular Assist Device for Korean Patients With Cardiogenic Shock) registry in Korea were analyzed. The study population was classified into obese and nonobese groups according to Asian Pacific criteria (BMI ≥25.0 kg/m² for obese). The clinical impact of obesity on in‐hospital mortality according to sex was analyzed using logistic regression analysis and restricted cubic spline curves. The in‐hospital mortality rate was significantly lower in obese men than nonobese men (34.2% versus 24.1%, respectively; P=0.004), while the difference was not significant in women (37.3% versus 35.8%, respectively; P=0.884). As a continuous variable, higher BMI showed a protective effect in men; conversely, BMI was not associated with clinical outcomes in women. Compared with patients with normal weight, obesity was associated with a decreased risk of in‐hospital death in men (multivariable‐adjusted odds ratio [OR], 0.63; CI, 0.43–0.92 [P=0.016]), but not in women (multivariable‐adjusted OR, 0.94; 95% CI, 0.55–1.61 [P=0.828]). The interaction P value for the association between BMI and sex was 0.023.

Conclusions

The obesity paradox exists and apparently occurs in men among patients with CS. The differential effect of BMI on in‐hospital mortality was observed according to sex.

Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT02985008.

Obesity as a mortality risk factor in the medical ward: a case control study

BACKGROUND

Research regarding the association between severe obesity and in-hospital mortality is inconsistent. We evaluated the impact of body mass index (BMI) levels on mortality in the medical wards. The analysis was performed separately before and during the COVID-19 pandemic.

METHODS

We retrospectively retrieved data of adult patients admitted to the medical wards at the Mount Sinai Health System in New York City. The study was conducted between January 1, 2011, to March 23, 2021. Patients were divided into two sub-cohorts: pre-COVID-19 and during-COVID-19. Patients were then clustered into groups based on BMI ranges. A multivariate logistic regression analysis compared the mortality rate among the BMI groups, before and during the pandemic.

RESULTS

Overall, 179,288 patients were admitted to the medical wards and had a recorded BMI measurement. 149,098 were admitted before the COVID-19 pandemic and 30,190 during the pandemic. Pre-pandemic, multivariate analysis showed a "J curve" between BMI and mortality. Severe obesity (BMI > 40) had an aOR of 0.8 (95% CI:0.7-1.0, p = 0.018) compared to the normal BMI group. In contrast, during the pandemic, the analysis showed a "U curve" between BMI and mortality. Severe obesity had an aOR of 1.7 (95% CI:1.3-2.4, p < 0.001) compared to the normal BMI group.

CONCLUSIONS

Medical ward patients with severe obesity have a lower risk for mortality compared to patients with normal BMI. However, this does not apply during COVID-19, where obesity was a leading risk factor for mortality in the medical wards. It is important for the internal medicine physician to understand the intricacies of the association between obesity and medical ward mortality.

Clinical Significance of Serum Lactate in Acute Myocardial Infarction: A Cardiac Magnetic Resonance Imaging Study

Little is known about causality and the pathological mechanism underlying the association of serum lactate with myocardial injury in patients with acute myocardial infarction (AMI). We evaluated data from 360 AMI patients undergoing percutaneous coronary intervention (PCI) using cardiovascular magnetic resonance imaging (CMR). Of these, 119 patients had serum lactate levels > 2.5 mmol/L on admission (high serum lactate group), whereas 241 patients had serum lactate levels ≤ 2.5 mmol/L (low serum lactate group). We compared the myocardial infarct size assessed by CMR between the two groups and performed inverse probability of treatment weighting (IPTW). In CMR analysis, myocardial infarct size was significantly greater in the high serum lactate group than in the low serum lactate group (22.0 ± 11.4% in the high serum lactate group vs. 18.9 ± 10.5% in the low serum lactate group; p = 0.011). The result was consistent after IPTW adjustment (21.5 ± 11.1% vs. 19.2 ± 10.4%; p = 0.044). In multivariate analysis, high serum lactate was associated with larger myocardial infarct (odds ratio 1.59; 95% confidence interval 1.00–2.51; p = 0.048). High serum lactate could predict advanced myocardial injury in AMI patients undergoing PCI.

Effect of Body Mass Index on the Clinical Outcomes of Adult Patients Treated With Venoarterial ECMO for Cardiogenic Shock

OBJECTIVE

Current guidelines consider obesity to be a relative contraindication to venoarterial extracorporeal membrane oxygenation (VA-ECMO) for refractory cardiogenic shock. The authors investigated the effect of body mass index (BMI) on clinical outcomes in patients treated with VA-ECMO for cardiogenic shock.

DESIGN

This was a retrospective and observational study.

SETTING

University hospital.

PARTICIPANTS

The study comprised 150 adult patients who underwent VA-ECMO for cardiogenic shock.

MEASUREMENTS AND MAIN RESULTS

The primary outcome was intensive care unit (ICU) mortality. Of the 150 included patients, 10 were underweight (BMI < 18.5 kg/m²), 62 were normal weight (BMI = 18.5-24.9 kg/m²), 34 were overweight (BMI = 25.0-29.9 kg/m²), 34 were obese class I (BMI = 30.0-34.9 kg/m²), and 10 were obese class II (BMI = 35.0-39.9 kg/m²). All-cause ICU mortality was 62% (underweight, 70%; normal weight, 53%; overweight, 65%; class I obese, 71%; class II obese, 70%). After multivariate logistic regression, BMI was not associated with ICU mortality (adjusted odds ratio [aOR] 0.99 [0.92-1.07], p = 0.8). Analysis by BMI category showed unfavorable mortality trends in underweight patients (aOR 3.58 [0.82-19.6], p = 0.11) and class I obese patients (aOR 2.39 [0.95-6.38], p = 0.07). No statistically significant differences were found among BMI categories in the incidences of complications.

CONCLUSION

The results suggested that BMI alone should not be considered an exclusion criterion for VA-ECMO. The unfavorable trend observed in underweight patients could be the result of malnutrition.

Body Mass Index and In-Hospital Management and Outcomes of Acute Myocardial Infarction

Background and Objectives: Contemporary data on the prevalence, management and outcomes of acute myocardial infarction (AMI) in relation to body mass index (BMI) are limited. Materials and Methods: Using the National Inpatient Sample from 2008 through 2017, we identified adult AMI hospitalizations and categorized them into underweight (BMI < 19.9 kg/m²), normal BMI and overweight/obese (BMI > 24.9 kg/m²) groups. We evaluated in-hospital mortality, utilization of cardiac procedures and resource utilization among these groups. Results: Among 6,089,979 admissions for AMI, 38,070 (0.6%) were underweight, 5,094,721 (83.7%) had normal BMI, and 957,188 (15.7%) were overweight or obese. Over the study period, an increase in the prevalence of AMI was observed in underweight and overweight/obese admissions. Underweight AMI admissions were, on average, older, with higher comorbidity, whereas overweight/obese admissions were younger and had lower comorbidity. In comparison to the normal BMI and overweight/obese categories, significantly lower use of coronary angiography (62.3% vs. 74.6% vs. 37.9%) and PCI (40.8% vs. 47.7% vs. 19.6%) was observed in underweight admissions (all p < 0.001). The underweight category was associated with significantly higher in-hospital mortality (10.0% vs. 5.5%; OR 1.23 (95% CI 1.18–1.27), p < 0.001), whereas being overweight/obese was associated with significantly lower in-hospital mortality compared to normal BMI admissions (3.1% vs. 5.5%; OR 0.73 (95% CI 0.72–0.74), p < 0.001). Underweight AMI admissions had longer lengths of in-hospital stay with frequent discharges to skilled nursing facilities, while overweight/obese admissions had higher hospitalization costs. Conclusions: In-hospital management and outcomes of AMI vary by BMI. Underweight status was associated with worse outcomes, whereas the obesity paradox was apparent, with better outcomes for overweight/obese admissions.

Association Between Body Mass Index and Outcomes in Venoarterial Extracorporeal Membrane Oxygenation

BACKGROUND

The association between obesity, or elevated body mass index (BMI), and outcomes in patients receiving venoarterial extracorporeal membrane oxygenation (VA-ECMO) has not been well established. Recent studies in patients receiving venovenous ECMO did not detect an association between obesity and increased mortality. The purpose of this retrospective observational study is to evaluate the association between BMI and survival in patients receiving VA-ECMO for cardiogenic shock.

METHODS

All patients >18 years of age supported on VA-ECMO for refractory cardiogenic shock in a single academic center between 2009 and 2019 were included. ECMO outcomes, including successful ECMO decannulation and 30-day survival, were analyzed after stratification according to BMI. Multivariable and univariate logistic regression were used to assess the association between BMI and VA-ECMO outcomes.

RESULTS

Of the total patients (n = 355) cannulated for VA-ECMO, 61.7% of the patients survived to ECMO recovery/decannulation, 45.5% of the patients survived to 30 days after ECMO decannulation, and 38.9% of the patients survived to hospital discharge with no statistically significant differences among the BMI groups. Multivariable logistic regression did not reveal any associations between obesity as defined by BMI and survival to ECMO decannulation (odds ratio [OR] 1.07 per 5 unit increase in BMI, 95% confidence interval [CI], 0.86-1.33; P = .57), 30-day survival (OR = 0.91, 95% CI, 0.73-1.14; P = .41) or survival to hospital discharge (OR = 0.95, 95% CI, 0.75-1.20; P = .66).

CONCLUSIONS

Despite potential challenges to cannulation and maintaining adequate flow during ECMO, this single centered, retrospective observational study did not detect association between BMI and survival to ECMO decannulation, 30-day survival, or survival to hospital discharge for patients requiring VA-ECMO for refractory cardiogenic shock. These data suggest that obesity alone should not exclude candidacy for VA-ECMO. The primary outcome in this retrospective study was survival of the ECMO therapy (survival to ECMO decannulation), defined as surviving >24 hours after decannulation without a withdrawal of care. Secondary outcomes included survival at 30 days and survival to hospital discharge.

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.

Influence of body mass index on the management and outcomes of acute myocardial infarction-cardiogenic shock in the United States, 2008-2017

BACKGROUND

There are limited data on influence of body mass index (BMI) on outcomes of acute myocardial infarction-cardiogenic shock (AMI-CS).

METHODS

Adult AMI-CS admissions from 2008 to 2017 were identified from the National Inpatient Sample and stratified by BMI into underweight (<19.9 kg/m²), normal-BMI (19.9-24.9 kg/m²) and overweight/obese (>24.9 kg/m²). Outcomes of interest included in-hospital mortality, invasive cardiac procedures use, hospitalization costs, and discharge disposition.

RESULTS

Of 339,364 AMI-CS admissions, underweight and overweight/obese constitute 2356 (0.7%) and 46,675 (13.8%), respectively. In 2017, compared to 2008, there was an increase in underweight (adjusted odds ratio [aOR] 6.40 [95% confidence interval {CI} 4.91-8.31]; p < 0.001) and overweight/obese admissions (aOR 2.93 [95% CI 2.78-3.10]; p < 0.001). Underweight admissions were on average older, female, with non-ST-segment-elevation AMI-CS, and higher comorbidity. Compared to normal and overweight/obese admissions, underweight admissions had lower rates of coronary angiography (57% vs 72% vs 78%), percutaneous coronary intervention (40% vs 54% vs 54%), and mechanical circulatory support (28% vs 46% vs 49%) (p < 0.001). In-hospital mortality was lower in underweight (32.9% vs 34.1%, aOR 0.64 [95% CI 0.57-0.71], p < 0.001) and overweight/obese (27.6% vs 38.4%, aOR 0.89 [95% CI 0.87-0.92], p < 0.001) admissions. Higher hospitalization costs were seen in overweight/obese admissions while underweight admissions were discharged more often to skilled nursing facilities.

CONCLUSION

Underweight patients received less frequent cardiac procedures and were discharged more often to skilled nursing facilities. Underweight and overweight/obese AMI-CS admissions had lower in-hospital mortality compared to normal BMI.

Obesity and Outcomes Following Cardiogenic Shock Requiring Acute Mechanical Circulatory Support

BACKGROUND

The association of obesity on outcomes in patients with cardiogenic shock requiring acute mechanical circulatory support has not been thoroughly investigated.

METHODS

We evaluated the National Readmission Database for adults with either acute myocardial infarction or heart failure complicated by cardiogenic shock requiring acute mechanical circulatory support between January 2016 and November 2017. Exposure was assessed using International Classification of Diseases, Tenth Revision codes for the degree of obesity with the reference being body mass index (BMI) of 20.0 to 29.9 group. Multiple logistic regression and Cox regression analysis were used to analyze in-hospital mortality and 30-day readmission, respectively.

RESULTS

The survey-weighted sample included a total of 35 555 hospitalizations with a mean age of 65.4±0.2 years and 29.8% females. Obesity was associated with higher in-hospital mortality (no obesity, 26.4% [BMI, 20.0-29.9] versus class I obesity, 25.0% [BMI, 30.0-34.9] versus class II obesity, 28.7% [BMI, 35.0-39.9] versus class III obesity, 34.9% [BMI, ≥40]; P<0.001). On stratified analysis, compared with a nonobese phenotype, younger adults (age <60) with class II and class III obesity (odds ratio, 1.9 [95% CI, 1.1-3.5], P=0.02; odds ratio, 2.1 [95% CI, 1.2-3.7], P=0.01) and older adults (age ≥60) with class III obesity (odds ratio, 1.7 [95% CI, 1.2-2.4], P=0.005) had higher mortality. There was no association between the degree of obesity and 30-day readmission.

CONCLUSIONS

Among adults with acute myocardial infarction or acute heart failure resulting in cardiogenic shock requiring acute mechanical circulatory support, younger adults with class II and class III obesity and older patients with class III obesity have a higher risk of in-hospital mortality compared with nonobese patients.

Body mass index and all-cause mortality in patients with cardiogenic shock: A systematic review and meta-analysis

BACKGROUND

The association between body mass index (BMI) and all-cause mortality of patients with Cardiogenic Shock (CS) is still controversial. The objective of this analysis is to summarize the available evidence of this association and perform meta-analysis using adjusted estimates.

METHODS

PubMed, Embase and Cochrane databases were systematically searched for eligible studies up to July 2020. Studies were considered eligible if they described the association between BMI and all-cause mortality of patients with CS, and those reporting adjusted estimates were included in the meta-analysis.

RESULTS

Three studies were identified and included total 345,281 participants. The pooled hazard ratio of all-cause mortality was 0.88(95% confidence interval (CI): 0.71-1.08, P = 0.23) when compared obesity with non-obese. In subgroup analysis, A subgroup analysis based on geographic region showed that obese patients had lower mortality compared with non-obese patients (OR = 0.71,95% CI 0.65-0.77, P < 0.00001) in USA, developed country and the retrospective study. Heterogeneity was not explained in pre-specified subgroups analysis.

CONCLUSION

Obesity was associated with increased adjusted all-cause mortality of patients with Cardiogenic Shock when compared to non-obese. Unexplained heterogeneity and suboptimal quality of studies limit the strength of the results. This seemingly paradoxical finding needs to be confirmed with further research.

The association between body mass index and in-hospital outcome among patients with acute myocardial infarction-Insights from China Acute Myocardial Infarction (CAMI) registry

BACKGROUND

The relationship between body mass index (BMI) and in-hospital mortality risk among patients with acute myocardial infarction (AMI) remains controversial.

METHODS AND RESULTS

We included 35,964 patients diagnosed with AMI in China Acute Myocardial Infarction registry between January 2013 and December 2016. Patients were categorized into 4 groups according to BMI level: BMI <18.5, 18.5-24.9, 25-30, and ≥30 kg/m² for underweight, normal, overweight, and obese groups, respectively. Clinical data were extracted for each patient, and multivariable logistic regression analysis was used to examine the association between BMI level and in-hospital mortality. Compared with normal-weight patients, obese patients were younger, more often current smokers, and more likely to have hypertension, hyperlipidemia, and diabetes. Multivariable regression analysis results demonstrated that compared with normal group, underweight group had significantly higher in-hospital mortality (odds ratio [OR]: 1.34; 95% confidence interval [CI]: 1.06-1.69; p = 0.016), while overweight group (OR: 0.86; 95% CI: 0.77-0.97; p = 0.011) and obese group (OR: 0.65; 95% CI: 0.46-0.91; p = 0.013) had lower mortality. All subgroups showed a trend toward lower in-hospital mortality risk as BMI increased.

CONCLUSIONS

Our study provided robust evidence supporting "obesity paradox" in a contemporary large-scale cohort of patients with AMI and demonstrated that increased BMI was independently associated with lower in-hospital mortality.

Outcomes in Cardiogenic Shock from Acute Coronary Syndrome Depending on Severity of Obesity

We reviewed 54,044 adult cases of cardiogenic shock (CS) accompanying acute coronary syndrome from the 2005 to 2014 Nationwide Inpatient Sample. We evaluated outcomes among patients who were nonobese, obese (body mass index 30.0 to 39.9 kg/m²) and extremely-obese (body mass index ≥40 kg/m²). A multivariate analysis was performed to assess their impact on in-hospital mortality. There were 3,602 (6.6%) and 1,610 (2.9%) admissions among patients who were obese and extremely-obese. Those obese and extremely-obese were younger compared with the nonobese (62.7 vs 61.2 vs 68.8 years, respectively; p <0.01) but had significantly greater comorbidity burden. CS patients who were not-obese were most likely to have an associated ST elevation myocardial infarction, compared with the obese and extremely-obese (67.7% vs 65.9% vs 60.7%; p <0.01). Compared to the nonobese, patients who were obese had higher rates of percutaneous coronary intervention (55.8% vs 51.5%; p <0.01) and coronary artery bypass grafting (24.0% vs 16.0%; p <0.01) whereas those extremely-obese had higher coronary artery bypass grafting rates (23.9% vs 16.0%; p <0.01) but similar percutaneous coronary intervention rates (51.1% vs 51.5%; p = 0.74). Short-term mechanical support use was lowest among the nonobese followed by the extremely-obese and obese. Adjusted analysis revealed that obesity predicted less (adjusted odd ratio 0.82, 95% confidence interval 0.76 to 0.90) and extreme-obesity predicted higher in-hospital mortality (adjusted odds ratio 1.17, 95% confidence interval 1.05 to 1.32) compared with the nonobese. In conclusion, obesity and extreme-obesity are associated with greater comorbidity burden among ACS related CS admissions. Obesity predicted less in-hospital mortality, whereas extreme obesity was associated with elevated in-hospital mortality.

Obesity Is Independently Associated With Higher Annual Burden and Costs of Hospitalization in Patients With Inflammatory Bowel Diseases

BACKGROUND & AIMS

Approximately 15%-40% patients with inflammatory bowel diseases (IBD) are obese. There is an inconsistent association between obesity and IBD phenotype and course. We conducted a nationally representative cohort study to estimate and compare the burden, costs, and causes for hospitalization in obese vs non-obese patients with IBD.

METHODS

Using the Nationwide Readmissions Database 2013, we identified obese (based on administrative claims code) and non-obese patients who had been hospitalized at least once, from January through June 2013, and followed them for re-hospitalization until December 2013. We compared annual burden (total days spent in hospital), costs, causes, and outcomes of hospitalization between obese and non-obese patients after 1:1 propensity score matching.

RESULTS

We identified 42,285 patients with IBD, of which 12.4% were obese. After propensity score matching, we included 5128 obese and 5128 non-obese IBD patients in our analysis. Compared to non-obese patients, obese patients spent more days in hospital annually (median, 8 vs 5 days) (P < .01), with higher hospitalization-related costs (median, $17,277 vs $11,847) (P < .01); this pattern persisted in subsets of high-need and high-cost patients. Compared to non-obese patients, obese patients were more likely to be hospitalized with preventable admissions (19% vs 15%) or cardiopulmonary complications (16% vs 12%).

CONCLUSIONS

In an analysis of data on patients with IBD from the Nationwide Readmissions Database 2013, we found obesity to be independently associated with higher burden and costs of hospitalizations. Strategies should be considered to target obesity as adjunctive therapy for patients with IBD.

In-Hospital Mortality and Major Adverse Cardiovascular Events after Kidney Transplantation in the United States

Background: Kidney transplantation (KT) is the treatment of choice for end-stage kidney disease. Cardiovascular disease is a major determinant of morbidity and mortality in patients with KT. Temporal trends in perioperative cardiovascular outcomes after KT are understudied, especially in light of an aging KT waitlist population. Methods: We performed a retrospective observational cohort study using the National Inpatient Sample for the years 2004–2013. All adult patients undergoing KT were identified using the appropriate International Classification of Diseases, 9th Revision, Clinical Modification codes. Demographic and hospital characteristics, discharge disposition, payer status, and major adverse cardiovascular events (MACEs) were summarized using summary statistics. Multivariate logistic regression was used to identify predictors of MACEs in the perioperative period of KT. Results: A total of 147,431 KTs were performed between 2004 and 2013. The mean age at KT went up from 48.1 to 51.8 years from 2004 to 2013. Medicare was the primary payer for 59.6% of the KTs. Overall average perioperative mortality was 0.5%, median length of stay was 5 days, and 6.5% of patients experienced an MACE, 78% of which were heart failures (HFs). Important predictors of perioperative MACEs were age ≥65 years (OR = 2.14), Medicare as primary payer (OR = 1.51), diabetes (OR = 1.46), recreational drug use (OR = 1.72), pulmonary circulation disorders (OR = 3.28), and malnutrition (OR = 1.91). Conclusion: Despite increases in age at the time of KT, the absolute risk of perioperative MACEs has remained stable from 2004 to 2013. HF is a major component of postoperative MACEs in KT. Malnutrition and pulmonary hypertension are major nontraditional predictors of perioperative MACE outcomes.