The impact of obesity on mortality in UA/non-ST-segment elevation myocardial infarction.

AIMS: Obesity is associated with diabetes mellitus and advanced coronary artery disease (CAD). Once a non-ST-elevation acute coronary syndrome has occurred, the association between obesity and prognosis is poorly defined. This study was designed to assess the impact of obesity on outcome after unstable angina/non-ST-segment elevation myocardial infarction (UA/NSTEMI) treated with early revascularization. METHODS AND RESULTS: In a prospective cohort study in 1676 consecutive patients with UA/NSTEMI we examined the association between presence of obesity and all-cause mortality. All patients underwent coronary angiography and, if appropriate, early catheter-based revascularization. Patients were divided into four groups according to body mass index (BMI): normal, 18.5-24.9 (n = 551); overweight, 25-29.9 (n = 824); obese, 30-34.9 (n = 244); and very obese, above 35 (n = 48). Obese and very obese patients were younger and had a higher incidence of hypertension, diabetes mellitus, elevated cardiac troponin T, and C-reactive protein levels. The angiographic extent of CAD was similar among the BMI groups. Median follow-up was 17 (interquartile range 6-31) months. Cumulative 3-year mortality rates were 9.9% for normal BMI, 7.7% for overweight, 3.6% for obese, and 0 (no death) for very obese (log-rank P = 0.043). Obese and very obese patients had less than half the long-term mortality when compared with normal BMI patients [hazard ratio (HR) 0.38, 95% confidence interval (CI) 0.18-0.81, P = 0.012]. This result remained significant after adjustment for confounding prognostic factors including coronary status and left ventricular function (adjusted HR 0.27, 95% CI 0.08-0.92, P = 0.036). CONCLUSION: Obesity is associated with improved outcome after UA/NSTEMI treated with early revascularization.     

Impact of obesity as a mortality predictor in high-risk patients with myocardial infarction or chronic heart failure: a pooled analysis of five registries

AIMS: To explore the influence of obesity on prognosis in high-risk patients with myocardial infarction (MI) or heart failure (HF). METHODS AND RESULTS: Individual data of 21 570 consecutively hospitalized patients from five Danish registries were pooled together. After a follow-up of 10.4 years, all-cause mortality using multivariate model and adjusted hazard ratios (HR) with 95% confidence intervals were calculated. Compared with normal weight [body mass index (BMI) 18.5-24.9 kg/m2], obesity class II (BMI >or= 35 kg/m2) was associated with increased risk of death in patients with MI but not HF [HR = 1.23 (1.06-1.44), P = 0.006 and HR = 1.13 (0.95-1.36), P = 0.95] (P-value for interaction = 0.004). Obesity class I (BMI 30-34.9 kg/m2) was not associated with increased risk of death in MI or HF [HR = 0.99 (0.92-1.08) and 1.00 (0.90-1.11), P > 0.1]. Pre-obesity (BMI 25-29.9 kg/m2) was associated with decreased death risk in MI but not HF [HR = 0.91 (0.87-0.96), P = 0.0006 and 1.04 (0.97-1.12), P = 0.34] (P-value for interaction = 0.007). Underweight (BMI < 18.5 kg/m2) patients were in increased death risk regardless of MI or HF [HR = 1.54 (1.35-1.75) and 1.37 (1.18-1.59), P < 0.001]. CONCLUSION: In patients with MI but not HF, the relationship between BMI and mortality is U-shaped with highest mortality in underweight and obese class II, but lowest in the other BMI classes.     

The “Obesity Paradox”: Does It Persist Among Israeli Patients With Decompensated Heart Failure? A Subanalysis of the Heart Failure Survey in Israel (HFSIS)

BackgroundEarlier studies among heart failure (HF) patients reported a paradox of reduced mortality rates in those with increased body mass index (BMI). Recently, however, it has been shown that obesity was not associated with better prognosis in certain groups. The aim of this study was to evaluate the “obesity paradox” among patients included in the Heart Failure Survey in Israel (HFSIS).Methods and ResultsClinical, demographic, and laboratory characteristics of 2,323 patients hospitalized with a diagnosis of acute or decompensated chronic HF in 25 public Israeli hospitals between March 1 and April 30, 2003, were categorized by BMI as: normal weight (18.5–24.9 kg/m²; n = 837), overweight (25.0–29.9 kg/m²; n = 877), or obese (≥30.0 kg/m²; n = 574), excluding 35 patients with BMI <18.5 kg/m². Survival over 15 months was inversely related to BMI category. Age-adjusted mortality hazard ratio (HR) was 0.95 (95% confidence interval [CI] 0.79–1.14) for overweight patients and 0.70 (95% CI 0.55–0.88) for obese patients compared with normal-weight patients. After further adjustment for gender, ejection fraction, New York Heart Association functional class, ischemic heart disease, diabetes, hypertension, dyslipidemia, renal function, and medications (angiotensin-converting enzyme inhibitor/angiotensin receptor blocker, β-blocker, spironolactone), obesity was associated with a nonsignificant HR of 0.79 (95% CI 0.59–1.05). Hypertension and dyslipidemia were also paradoxically associated with better survival in our model (HR 0.74, CI 0.59–0.92; and HR 0.77, CI 0.63–0.94; respectively; both P < .05).ConclusionsOur study falls in line with the obesity paradox observation (in obese but not overweight patients) in a large survey of HF patients, although this finding was not statistically significant on multivariate adjustment analysis.     

The relationship between obesity and mortality in patients with heart failure

OBJECTIVES: The study aimed to evaluate the role of obesity in the prognosis of patients with heart failure (HF). BACKGROUND: Previous reports link obesity to the development of HF. However, the impact of obesity in patients with established HF has not been studied. METHODS: We analyzed 1,203 patients with advanced HF followed in a comprehensive HF management program. The patients were subclassified into categories of body mass index (BMI) defined as: underweight BMI <20.7 (n = 164), recommended BMI 20.7 to 27.7 (n = 692), overweight BMI 27.8 to 31 (n = 168) and obese BMI >31 (n = 179). This sample size allows the detection of small effects (0.02), with a power of 0.80 and an alpha level of 0.05 for comparing one-year survival between BMI groups. RESULTS: The four BMI groups had similar profiles in terms of ejection fraction (mean 0.22), sodium, creatinine and smoking. The obese and overweight groups had significantly higher rates of hypertension and diabetes, as well as higher levels of cholesterol, triglycerides and low density lipoprotein cholesterol. The four BMI groups had similar survival rates. Ejection fraction, HF etiology and angiotensin-converting enzyme inhibitor use predicted survival on univariate analysis (p < 0.01), although BMI did not. On multivariate analysis, cardiopulmonary exercise tests, pulmonary capillary wedge pressure and serum sodium were strong predictors of survival (p < 0.05). Higher BMI was not a risk factor for increased mortality, but was associated with a trend toward improved survival. CONCLUSIONS: In a large cohort of patients with advanced HF of multiple etiologies, obesity is not associated with increased mortality and may confer a more favorable prognosis. Further studies need to delineate whether weight loss promotion in medically optimized patients with HF is a worthwhile therapeutic goal.     

Excess weight at time of presentation of myocardial infarction is associated with lower initial mortality risks but higher long-term risks including recurrent re-infarction and cardiac death

OBJECTIVES: To evaluate the influence of elevated body mass index (BMI) on short- and long-term survival following acute myocardial infarction (AMI). BACKGROUND: Recent studies suggest an obesity survival paradox in individuals undergoing percutaneous coronary intervention with better 30-day and 1-year outcomes in obese relative to normal weight patients. We tested a similar obesity paradox hypothesis following acute myocardial infarction. METHODS: Short- and long-term all-cause mortality, and risk of recurrent AMI were evaluated according to BMI status in 894 consecutive survivors of AMI <80 years of age admitted to the Mayo Clinic Coronary Care Unit between January 1, 1988 and April 16, 2001. Normal weight, overweight and obesity were defined as BMI <25, 25-29.9, and >30 kg/m(2), respectively. RESULTS: Overall mortality following hospital discharge was significantly lower in overweight and obese patients and was mostly attributable to lower 6-month mortality (adjusted HR = 0.47, P = 0.01 for BMI >25 kg/m(2)) relative to normal weight patients, while long-term mortality among 6-month survivors was similar in all 3 groups. The risk of recurrent AMI was higher in patients with BMI >25 kg/m(2) (adjusted HR = 2.30, P = 0.01). Overweight and obese patients were significantly more likely to die from cardiac rather than non-cardiac causes (P < 0.01). CONCLUSIONS: Following AMI, overweight and obese individuals although paradoxically protected from short-term death have a long-term mortality risk that is similar to normal weight individuals. Younger age at the time of initial infarction and fewer non-cardiovascular comorbidities presumably explain the short-lived obesity survival paradox following myocardial infarction.     

Impact of obesity on long-term prognosis following acute myocardial infarction

OBJECTIVE: To evaluate the impact of obesity on mortality in patients with acute myocardial infarction. METHODS: This study comprises 6676 consecutive patients with acute myocardial infarction screened for entry into the Danish Trandolapril Cardiac Evaluation (TRACE) study. At baseline, body mass index (BMI) and waist to hip ratio (WHR) were measured. Survival status was determined after 8-10 years. RESULTS: BMI was used to divide patients into 4 groups: underweight, normal weight, overweight and obese. The normal weight group was used as reference for the other groups. WHR was divided in quartiles and the lowest quartile was used as reference for the three other quartiles. The prevalence of overweight (BMI 25-29.9 kg/m(2)) and obesity (BMI>30 kg/m(2)) were 48% and 13% in males and 31% and 13% in females. Obese patients were younger, less often smokers and more frequently suffered from diabetes and hypertension. In both men and women, there was no association between obesity assessed as BMI and mortality [men: adjusted RR=0.99 (0.85-1.14, p=0.3); women: adjusted RR=0.90 (0.74-1.10, p=0.2)]. Men with WHR in the upper quartile had an increased mortality [adjusted RR=1.21 (1.07-1.37, p<0.01)]. Increasing WHR in women showed a trend of increased mortality, although this was not significant [adjusted RR=1.13 (0.95-1.34, p=0.2)]. CONCLUSION: In patients with acute myocardial infarction overall obesity as assessed by body mass index is inversely related to mortality. However, abdominal obesity appears to be an independent predictor of all-cause mortality in men and perhaps also in women.     

Healthcare outcomes for patients with type 2 diabetes with and without comorbid obesity

AimsExamine the burden of comorbid obesity associated with type 2 diabetes (T2D).MethodsThe IBM® MarketScan® Explorys Claims Electronic Medical Records Data were used to identify adults with T2D, two recorded body mass index (BMI) values, and continuous insurance coverage from 1 year prior through 1 year post index date. Patients with index BMI ≥18 kg/m² and <30 kg/m² (normal/overweight) were matched to patients with index BMI ≥ 30 kg/m² (obese) using propensity score matching (PSM). Using the PSM cohort, multivariable analyses examined the association between obesity and patient comorbidities, healthcare costs, and resource utilization.ResultsIn the matched cohort (16,006 normal/overweight; 16,006 obese), multivariable analyses showed that obesity, compared to normal/overweight, was associated with increased odds of a diabetes-related comorbidity (Odds Ratio [OR] = 1.29; 95% Confidence Interval [CI] 1.21–1.38) and an obesity-related comorbidity (OR = 1.42; 95% CI 1.29–1.56). Obesity was also associated with significantly higher annual diabetes-related and all-cause total costs and resource utilization.ConclusionsThis research increases the knowledge of how patients with T2D and obesity should be of greater concern for healthcare providers compared to T2D patients without comorbid obesity, given their worse comorbidity profile, increased resource utilization, and higher healthcare costs.     

B-type natriuretic peptide levels in obese patients with advanced heart failure.

Although recent studies show that obesity, or elevated body mass index (BMI), is associated with lower levels of B-type natriuretic peptide (BNP), it is unknown whether BMI affects the prognostic value of BNP in heart failure (HF). This study confirms the relationship between high BMI and low BNP in patients with advanced systolic HF. Despite relatively lower levels of BNP in overweight and obesity, BNP predicts worse symptoms, impaired hemodynamics, and higher mortality in HF at all levels of BMI.OBJECTIVES: This study aimed to examine the influence of obesity on the predictive value of the B-type natriuretic peptide (BNP) assay in heart failure (HF). BACKGROUND: Recent studies show that obesity, or elevated body mass index (BMI), is associated with lower circulating levels of BNP both in the general population and in patients with HF. METHODS: We analyzed data from 316 systolic HF (left ventricular ejection fraction [LVEF] < or =40%) patients [age, 53 +/- 13 years; mean LVEF, 24 +/- 7%; 48% ischemic] followed up at a university HF center. Patients were divided into categories of BMI: lean (BMI <25 kg/m2), overweight (BMI = 25 to 29.9 kg/m2), and obese (BMI > or =30 kg/m2). RESULTS: The BNP levels were significantly lower in overweight and obese compared with lean patients (p = 0.0001); median BNP (interquartile range) for the lean (n = 131), overweight (n = 99), and obese (n = 86) groups was 747 (272 to 1,300), 380 (143 to 856), and 332 (118 to 617) pg/ml, respectively. In each BMI category, elevated BNP was significantly associated with worse symptoms and higher pulmonary capillary wedge pressure. Higher BNP was also a significant independent predictor of survival independent of BMI. Optimal BNP cutoff for prediction of death or urgent transplant in lean, overweight, and obese HF patients was 590, 471, and 342 pg/ml, respectively. CONCLUSIONS: Although BNP levels are relatively lower in overweight and obese HF patients, BNP predicts worse symptoms, impaired hemodynamics, and higher mortality at all levels of BMI.     

Body mass index, prognosis and mode of death in chronic heart failure: results from the Valsartan Heart Failure Trial

AIMS: To assess the relationship between body mass index (BMI), mortality and mode of death in chronic heart failure (CHF) patients; to define the shape of the relationship between BMI and mortality. METHODS AND RESULTS: We performed a post-hoc analysis of 5010 patients from the Valsartan Heart Failure Trial. The end-points of the study were all-cause and cardiovascular mortality. Mortality rate was 27.2% in underweight patients (BMI<22 kg/m2), 21.7% in normal weight patients (BMI 22-24.9 kg/m2), 17.9% in overweight patients (BMI 25-29.9 kg/m2) and 16.5% in obese patients (BMI>30 kg/m2) (p<0.0001). The rates of non-cardiovascular death did not differ among groups. The risk of death due to progressive heart failure was 3.4-fold higher in the underweight than in the obese patients (p<0.0001). Normal weight, overweight and obese patients had lower risk of death as compared with underweight patients (p=0.019, HR 0.76, 95% CI 0.61-0.96; p=0.0005, HR 0.68, 95% CI 0.55-0.84; p=0.003, HR 0.67, 95% CI 0.52-0.88, respectively) independently of symptoms, ventricular function, beta-blocker use, C-reactive protein and brain natriuretic peptide levels. CONCLUSIONS: In CHF patients a higher BMI is associated with a better prognosis independently of other clinical variables. The relationship between mortality and BMI is monotonically decreasing.     

The obesity paradox: body mass index and outcomes in patients with heart failure

BACKGROUND: In the general population, obesity is associated with increased risk of adverse outcomes. However, studies of patients with chronic disease suggest that overweight and obese patients may paradoxically have better outcomes than lean patients. We sought to examine the association of body mass index (BMI) and outcomes in stable outpatients with heart failure (HF). METHODS: We analyzed data from 7767 patients with stable HF enrolled in the Digitalis Investigation Group trial. Patients were categorized using baseline BMI (calculated as weight in kilograms divided by the square of height in meters) as underweight (BMI <18.5), healthy weight (BMI, 18.5-24.9, overweight (BMI, 25.0-29.9), and obese (BMI > or =30.0). Risks associated with BMI groups were evaluated using multivariable Cox proportional hazards models over a mean follow-up of 37 months. RESULTS: Crude all-cause mortality rates decreased in a near linear fashion across successively higher BMI groups, from 45.0% in the underweight group to 28.4% in the obese group (P for trend <.001). After multivariable adjustment, overweight and obese patients were at lower risk for death (hazard ratio [HR], 0.88; 95% confidence interval [CI], 0.80-0.96, and HR, 0.81; 95% CI, 0.72-0.92, respectively), compared with patients at a healthy weight (referent). In contrast, underweight patients with stable HF were at increased risk for death (HR 1.21; 95% CI, 0.95-1.53). CONCLUSIONS: In a cohort of outpatients with established HF, higher BMIs were associated with lower mortality risks; overweight and obese patients had lower risk of death compared with those at a healthy weight. Understanding the mechanisms and impact of the "obesity paradox" in patients with HF is necessary before recommendations are made concerning weight and weight control in this population.     

The Impact of Obesity on Early Postoperative Outcomes in Adults with Congenital Heart Disease

Background. As the prevalence of obesity continues to increase, it now includes the growing number of patients with congenital heart disease (CHD). This particular obese patient population may pose additional intraoperative as well as postoperative challenges that may contribute to poor outcomes. Our aims were to determine the influence of obesity on morbidity and mortality in adults with CHD undergoing surgical repair at a free standing children's hospital. Methods. A retrospective analysis of adult (≥18 years) CHD surgery cases from 2002 to 2008 was performed. Congenital heart lesions were defined as mild, moderate, or complex. Patients were categorized by body mass index (BMI): underweight (BMI < 20 kg/m²), normal (BMI 20–24.9 kg/m²), overweight (BMI 25–29.9 kg/m²), and obese (BMI ≥ 30 kg/m²). Demographics, incidence of mortality, or specific morbidities were statistically compared using Fisher's exact test and analyses of variance (anova s). Results. In this population (n = 165), overweight (29%) and obese (22%) patients were prevalent. Hypertension (HTN) and pre‐HTN were more prevalent in obese and overweight patients. Postoperative renal dysfunction was observed in obese patients with complex CHD (P= .04). Mortality was not different among groups. Conclusions. Obesity is becoming increasingly common among adults with CHD. Despite marginal evidence of postoperative renal complications in obese patients with CHD of severe complexity, the overall presence of obesity did not influence mortality or short term postoperative morbidities.     

Effect of obesity on early morbidity and mortality following cardiac surgery

BACKGROUND: The prevalence of obesity in most developed nations, including Australia, continues to rise and represent an increasing public health concern. Obesity has been considered a major risk factor in patients undergoing cardiac and other major surgery. METHODS: We retrospectively analysed prospectively collected data of consecutive patients undergoing cardiac surgery between June 2001 and February 2006 at two Australian public hospitals. Patients were divided into three groups by body mass index (BMI): non-obese (BMI 20-30), obese (BMI>30-40) and morbidly obese (BMI>40). Associations between early mortality and morbidity and obesity were assessed by univariate and multivariate methods. RESULTS: Out of 4053 patients, 85 were excluded for BMI<20. A total of 2743 patients were defined as non-obese, 1136 obese and 89 morbidly obese. There were no significant differences in operative mortality, stroke, pneumonia, new renal failure, atrial fibrillation, prolonged ventilation, reintubation, readmission to intensive care, prolonged length of hospital stay or readmission within 30 days. The morbidly obese group had increased rates of deep sternal infection by univariate (odds ratio [OR] 6.4, 95% confidence interval [CI] 2.1-19.1, p<0.001) and multivariate (OR 13.1, CI 3.4-50.7, p<0.001) analysis. The obese group had a lower rate of re-operation for bleeding by univariate (OR 0.61, CI 0.41-0.91, p=0.01) and multivariate (OR 0.64, CI 0.42-0.99, p=0.04) analysis. CONCLUSION: Apart from an increased rate of deep sternal wound infection, obesity is not associated with early mortality or other post-operative complications. The protective effect of obesity on re-operation for bleeding requires further study.     

Survival of chronic hypercapnic COPD patients is predicted by smoking habits, comorbidity, and hypoxemia

STUDY OBJECTIVES: Chronic hypercapnia in patients with COPD has been associated with a poor prognosis. We hypothesized that, within this group of chronic hypercapnic COPD patients, factors that could mediate this hypercapnia, such as decreased maximum inspiratory mouth pressure (P(I(max))), decreased maximum expiratory mouth pressure (P(E(max))), and low hypercapnic ventilatory response (HCVR), could be related to survival. Other parameters, such as arterial blood gas values, airway obstruction (FEV1), body mass index (BMI), current smoking status, and the presence of comorbidity were studied as well. METHODS: A cohort of 47 chronic hypercapnic COPD patients recruited for short-term trials (1 to 3 weeks) in our institute was followed up for 3.8 years on average. Survival was analyzed using a Cox proportional hazards model. The risk factors considered were analyzed, optimally adjusted for age and gender. RESULTS: At the time of analysis 18 patients (10 male) were deceased. After adjusting for age and gender, P(I(max)), P(E(max)), and HCVR were not correlated with survival within this hypercapnic group. Current smoking (hazard ratio [HR], 7.0; 95% confidence interval [CI], 1.4 to 35.3) and the presence of comorbidity (HR, 5.5; 95% CI, 1.7 to 18.7) were associated with increased mortality. A higher Pa(O2) affected survival positively (HR, 0.6 per 5 mm Hg; 95% CI, 0.4 to 1.0). Pa(CO2) tended to be lower in survivors, but this did not reach statistical significance (HR, 2.0 per 5 mm Hg; 95% CI, 0.9 to 4.3). FEV1 and BMI were not significantly related with survival in hypercapnic COPD patients. CONCLUSION: In patients with chronic hypercapnia, only smoking status, the presence of comorbidity, and Pa(O2) level are significantly associated with survival. Airway obstruction, age, and BMI are known to be predictors of survival in COPD patients in general. However, these parameters do not seem to significantly affect survival once chronic hypercapnia has developed.     

Comorbidity Significantly Affects Clinical Outcome After Cardiac Resynchronization Therapy Regardless of Ventricular Remodeling

BackgroundThe influence of comorbid conditions on ventricular remodeling, functional status, and clinical outcome after cardiac resynchronization therapy (CRT) is insufficiently elucidated.Methods and ResultsThe influence of different comorbid conditions on left ventricular remodeling, improvement in New York Heart Association (NYHA) functional class, hospitalizations for heart failure, and all-cause mortality after CRT implantation was analyzed in 172 consecutive patients (mean age 71 ± 9 y), implanted from October 2008 to April 2011 in a single tertiary care hospital. During mean follow-up of 18 ± 9 months, 21 patients died and 57 were admitted for heart failure. Left ventricular remodeling and improvement in NYHA functional class were independent from comorbidity burden. However, diabetes mellitus (hazard ratio [HR] 3.45, 95% confidence interval [CI] 1.24–9.65) and chronic kidney disease (HR 3.11, 95% CI 1.10–8.81) were predictors of all-cause mortality, and the presence of chronic obstructive pulmonary disease (HR 1.89, 95% CI 1.02–3.53) was independently associated with heart failure admissions. Importantly, those 3 comorbid conditions had an additive negative impact on survival and heart failure admissions, even in patients with reverse left ventricular remodeling.ConclusionsReverse ventricular remodeling and improvement in functional status after CRT implantation are independent from comorbidity burden. However, comorbid conditions remain important predictors of all-cause mortality and heart failure admissions.     

Impaired response of cardiac autonomic nervous system to glucose load in severe obesity

OBJECTIVE: This study was undertaken to further analyze the response of the cardiovascular autonomic nervous system (ANS) to changes in plasma insulin concentration induced by an oral glucose load. We hypothesized that, as a consequence of insulin resistance, an inability of insulin to increase the sympathetic modulation of heart rate (HR) and blood pressure (BP) would be observed in normotensive obese patients. METHODS: We used spectral analysis to measure simultaneously the short-term variability of HR and BP in 23 never-obese subjects and in 70 normotensive overweight or obese patients subdivided into 3 subgroups: (1) overweight group (body mass index [BMI], 25-29.9 kg/m 2 ), n = 23; (2) class I-II obese group (BMI, 30-39.9 kg/m 2 ), n = 23; (3) class III obese group (BMI, > or =40 kg/m 2 ), n = 23. RESULTS: Oral glucose ingestion and the related increased insulinemia caused significant changes in the indices of sympathetic modulation (low-frequency [LF] power and LF/high-frequency ratio) of both HR and BP in normal weight, overweight, and obese subjects. However, the LF increments gradually decreased with the BMI classes, suggesting that sympathetic nervous system modulation in these subjects may be insulin-resistant. CONCLUSION: Obesity could develop resistance to the sympatho-excitatory effects of insulin that might play a role in the etiology of obesity. Spectral analysis of BP and HR can be used in research to evaluate the reactivity of the sympathetic nervous system in a manner that represents another feature of the obesity/insulin-resistance syndrome.     

Inverse association of mortality and body mass index in patients with left ventricular systolic dysfunction of both ischemic and non‐ischemic etiologies

BackgroundObesity is a worldwide epidemic that has been associated with poor outcomes. Previous studies have demonstrated an inverse relationship between body mass index (BMI) and outcomes, the ''obesity paradox'', in several diseases.HypothesisWe sought to evaluate whether the obesity paradox is present in patients with left ventricular systolic dysfunction (LVSD) of all etiologies, using all‐cause mortality as the primary endpoint and hospitalization as the secondary endpoint.MethodsWe conducted a retrospective cohort study of LVSD patients (n = 18 003) seen within the University of Pittsburgh Medical Center network between January 2011 and December 2017. Patients were divided into four BMI categories (underweight, normal weight, overweight, and obese) and stratified by left ventricular ejection fraction (LVEF): <20%, 20–35%, and 35–50%.ResultsOver a median follow‐up of 2.28 years, higher BMI (mean 28.9 ± 6.8) was associated with better survival for the overall cohort and within LVEF strata (p < .0001). The most common cause of hospitalization was subendocardial infarction among underweight and normal weight patients and heart failure among overweight and obese patients. Cox proportional hazards model showed that BMI, age, and comorbid conditions of diabetes mellitus, chronic obstructive pulmonary disease, chronic kidney disease, and prior myocardial infarction are independent predictors of death.ConclusionsOur results support the existence of an obesity paradox impacting all‐cause mortality in patients with LVSD of ischemic and non‐ischemic etiologies even after adjusting for LVEF and comorbidities. Additional research is needed to understand the effect of weight loss on survival once a diagnosis of LVSD is established.     

Obesity and outcomes in patients treated with chemoradiotherapy for esophageal carcinoma

Body mass index (BMI) is a risk factor for comorbid illnesses and cancer development. It was hypothesized that obesity status affects disease outcomes and treatment‐related toxicities in esophageal cancer patients treated with chemoradiotherapy (CRT). From March 2002 to April 2010, 405 patients with non‐metastatic esophageal carcinoma at MD Anderson Cancer Center treated with either definitive or neoadjuvant CRT were retrospectively analyzed. Patients were categorized as either obese (BMI ≥ 25 kg/m²) or nonobese (BMI < 25 kg/m²). Progression‐free survival and overall survival times were examined using the Kaplan–Meier method and Cox proportional hazards regression analysis. One hundred fifteen (28.4%) patients were classified as nonobese and 290 (71.6%) as obese. Obese patients were more likely than others to have several comorbid diseases (P < 0.001), adenocarcinoma located distally (P < 0.001), and have undergone surgery (P = 0.004). Obesity was not associated with either worse operative morbidity/mortality (P > 0.05) or worse positron emission tomography tumor response (P = 0.46) on univariate analysis, nor with worse pathologic complete response (P = 0.98) on multivariate analysis. There was also no difference in overall survival, locoregional control, or metastasis‐free survival between obese and nonobese patients (P = 0.86). However, higher BMI was associated with reduced risk of chemoradiation‐induced high‐grade esophagitis (P = 0.021), esophageal stricture (P < 0.001), and high‐grade hematologic toxicity (P < 0.001). In esophageal cancer patients treated with CRT, obesity is not predictive of poorer disease outcomes or operative morbidities; instead, data suggest it may be associated with decreased risk of acute chemotherapy‐ and radiotherapy‐related treatment toxicities.     

Effect of body mass index on risk of long-term mortality following coronary artery bypass grafting

The effect of obesity on long-term mortality after coronary artery bypass grafting (CABG) remains inconclusive, partly due to methodologic issues in previous studies. We examined the effect of obesity on long-term mortality (up to a 6-year follow-up) in adult patients with a body mass index (BMI) > or =18.5 kg/m2 who underwent CABG at Baylor University Medical Center (Dallas, Texas) between January 1998 and August 1999 (n = 1,209). Unadjusted analysis indicated a strong association between BMI and long-term mortality (p = 0.001), with a decreased risk of mortality associated with increasing BMI. After adjusting for factors shown to be confounders of this relation (age, diabetes mellitus, chronic obstructive lung disease, renal failure, ejection fraction, and left main disease), the estimated association was no longer significant (p = 0.425). In conclusion, the apparent survival benefit associated with higher BMI became nonsignificant when the relation between mortality and BMI was adjusted, first for age and then for diabetes mellitus, chronic obstructive lung disease, renal failure, ejection fraction, and left main disease. This relation was masked in the crude analysis primarily by the effect of age. Patients with a high BMI were typically younger than patients with a lower BMI, suggesting that physicians and surgeons may only recommend/perform CABG for patients with a high BMI with an otherwise lower risk profile.     

Body Mass Index and Survival in Men and Women Aged 70 to 75

OBJECTIVES: To examine in an older population all‐cause and cause‐specific mortality associated with underweight (body mass index (BMI)<18.5), normal weight (BMI 18.5–24.9), overweight (BMI 25.0–29.9), and obesity (BMI≥30.0). DESIGN: Cohort study. SETTING: The Health in Men Study and the Australian Longitudinal Study of Women's Health. PARTICIPANTS: Adults aged 70 to 75, 4,677 men and 4,563 women recruited in 1996 and followed for up to 10 years. MEASUReMENTS: Relative risk of all‐cause mortality and cause‐specific (cardiovascular disease, cancer, and chronic respiratory disease) mortality. RESULTS: Mortality risk was lowest for overweight participants. The risk of death for overweight participants was 13% less than for normal‐weight participants (hazard ratio (HR)=0.87, 95% CI=0.78–0.94). The risk of death was similar for obese and normal‐weight participants (HR=0.98, 95% CI=0.85–1.11). Being sedentary doubled the mortality risk for women across all levels of BMI (HR=2.08, 95% CI=1.79–2.41) but resulted in only a 28% greater risk for men (HR=1.28 (95% CI=1.14–1.44). CONCLUSION: These results lend further credence to claims that the BMI thresholds for overweight and obese are overly restrictive for older people. Overweight older people are not at greater mortality risk than those who are normal weight. Being sedentary was associated with a greater risk of mortality in women than in men.     

The effect of weight loss on the outcome after coronary artery bypass grafting in obese patients

The role of body mass index (BMI) in the setting of coronary artery bypass graft (CABG) surgery has been a focus of past studies. However, the effects of postoperative weight loss in patients after CABG is yet to be known. We performed a retrospective study of 899 patients who underwent CABG at our institution. Perioperative patient information was collected from an onsite electronic record system. Patients were grouped into four BMI categories: normal controls, overweight, obese and morbidly obese. Based on the postoperative BMI changes, patients were then grouped into three categories: gainers, no change and losers. Statistical analyses were performed using analysis of variance and linear regression to establish an association among the data. Hazard ratios (HR) and cumulative survival were obtained by the Cox-Mantel and Kaplan-Meier analyses, respectively. The normal controls exhibited a markedly higher mortality postoperatively, at 27.9%, especially when compared with the obese individuals (16.1%). Patients who lost weight faced a significantly increased risk of mortality than those who experienced no changes or gained weight after surgery. This trend was especially salient among the obese patients, who more than tripled their mortality risk (HR = 3.24) versus individuals who gained weight, and more than doubled their risk (HR = 2.87) versus those who had no changes. We conclude that obesity confers a survival advantage in the setting of the CABG surgery. Weight loss among all BMI categories of patients studied results in an adverse effect on postoperative survival.