Obesity and outcomes among patients with established atrial fibrillation. Influence of obesity on outcomes in atrial fibrillation: yet another obesity paradox. Relation of Nonvalvular Atrial Fibrillation to Body Mass Index (from the SPORTIF Trials). Body mass index and adverse events in patients with incident atrial fibrillation. Obesity, Physical Activity, and Their Interaction in Incident Atrial Fibrillation in Postmenopausal Women Overweight and obesity as risk factors for atrial fibrillation or flutter: the Danish Diet, Cancer, and Health Study. The Influence of Body Mass Index on Outcomes in Patients Undergoing Cardiac Surgery: Does the Obesity Paradox Really Exist? Reverse causality and confounding and the associations of overweight and obesity with mortality. Is obesity a predictor of mortality, morbidity and readmission after cardiac surgery? Relationship between body mass index and left atrial appendage thrombus in nonvalvular atrial fibrillation The effect of obesity and weight loss on aortic pulse wave velocity as assessed by magnetic resonance imaging. Obesity paradox in patients with hypertension and coronary artery disease. The obesity paradox in men with coronary heart disease and heart failure: The role of muscle mass and leptin☆☆☆★ Physical Activity, Obesity, Weight Change, and Risk of Atrial Fibrillation: The Atherosclerosis Risk in Communities Study Obesity and Mortality in a Prospective Study of a Middle-Aged Industrial Population Obesity paradox in coronary artery bypass grafting: myth or reality? Big men and atrial fibrillation: effects of body size and weight gain on risk of atrial fibrillation in men.
Atrial fibrillation ( AF ) and obesity have reached epidemic proportions . The impact of obesity on clinical outcomes in patients with established AF is unknown . We analyzed 2,492 patients in the Atrial Fibrillation Follow-Up Investigation of Rhythm Management ( AFFIRM ) study .  Body mass index ( BMI ) was evaluated as a categorical variable ( normal 18.5 to < 25 kg/m(2 ) , overweight 25 to < 30 kg/m(2 ) , obese > or=30 kg/m(2 ) ) . Rate of death from any cause was higher in the normal BMI group ( 5.8 per 100 patient-years ) than in the overweight and obese groups ( 3.9 and 3.7 , respectively ) . Cardiovascular death rate was highest in the normal BMI group ( 3.1 per 100 patient-years ) , lowest in the overweight group ( 1.5 per 100 patient-years ) , and intermediate in the obese group ( 2.1 per 100 patient-years ) . After adjustment for baseline factors , differences in risk of death from any cause were no longer significant . However , overweight remained associated with a lower risk of cardiovascular death ( hazard ratio 0.47 , p = 0.002 ) . Obese patients were more likely to have an uncontrolled heart rate at rest , but rhythm-control strategy success was similar across BMI categories . In each BMI category , risk of death from any cause was similar for patients r and omized to a rhythm- or rate-control strategy . In conclusion , in patients with established AF , overweight and obesity do not adversely affect overall survival . Obesity does not appear to affect the relative benefit of a rate- or rhythm-control strategy BACKGROUND Obese patients have favorable outcomes in congestive heart failure , hypertension , peripheral vascular disease , and coronary artery disease . Obesity also has been linked with increased incidence of atrial fibrillation , but its influence on outcomes in atrial fibrillation patients has not been investigated . The objective of this research is to investigate the effect of obesity on outcomes in atrial fibrillation . METHODS The Atrial Fibrillation Follow-up Investigation of Rhythm Management ( AFFIRM ) study was one of the largest multicenter trials of atrial fibrillation , with 4060 patients . Subjects were r and omized to rate versus rhythm-control strategy . We performed a post hoc analysis of the National Heart , Lung and Blood Institute limited access data set of atrial fibrillation patients who had body mass index ( BMI ) data available in the AFFIRM study . BMI data were not available on 1542 patients . Patients with BMI > or=18.5 were split into normal ( 18.5 - 25 ) , overweight ( 25 - 30 ) , and obese ( > 30 ) categories as per BMI ( kg/m(2 ) ) . Multivariate Cox proportional hazards regression was used on the eligible 2492 patients . End points were all-cause mortality and cardiovascular mortality . RESULTS Over three fourths of all patients in our cohort were overweight or obese . There were 304 deaths ( 103 among normal weight , 108 among overweight , and 93 among obese ) and 148 cardiovascular deaths ( 54 among normal weight , 41 among overweight , and 53 among obese ) over a mean period of 3 years of patient follow-up . On multivariate analysis , overweight ( hazard ratio [ HR ] 0.64 ; 95 % confidence interval [ CI ] , 0.48 - 0.84 ; P=.001 ) and obese ( HR 0.80 ; 95 % CI , 0.68 - 0.93 ; P=.005 ) categories were associated with lower all-cause mortality as compared with normal weight . Overweight ( HR 0.40 ; 95 % CI , 0.26 - 0.60 ; P < .001 ) and obese patients ( HR 0.77 ; 95 % CI , 0.62 - 0.95 ; P=.01 ) also had lower cardiovascular mortality as compared with the normal weight patients . CONCLUSIONS Although in prior studies , obesity has been associated with increased risk of atrial fibrillation , an obesity paradox exists for outcomes in atrial fibrillation . Obese patients with atrial fibrillation appear to have better long-term outcomes than nonobese patients Obesity is well-established as a major cardiovascular ( CV ) risk factor . Obesity confers a greater risk for developing atrial fibrillation ( AF ) , but the relation between obesity and established nonvalvular AF for stroke and all-cause death is still unclear . To ascertain the prevalence of overweight and obesity in patients with nonvalvular AF , their influence on adverse events , and the relation with anticoagulation control , we performed this post hoc analysis of the pooled Stroke Prevention using an Oral Thrombin Inhibitor in patients with atrial Fibrillation ( SPORTIF ) III and V data sets . For this study , we analyzed all patients assigned to the warfarin arm with data on body mass index ( BMI ) . Time in therapeutic range was used as an index of the quality of anticoagulation control . The 3,630 patients eligible for this analysis were categorized as follows : ( 1 ) BMI 18.5 to 24.9 ( " normal weight " ) in 24.1 % ; ( 2 ) BMI 25.0 to 29.9 ( " overweight " ) in 39.8 % ; and BMI ≥30 ( " obese " ) in 36.1 % . Both overweight ( hazard ratio [ HR ] 0.70 ) and obese ( HR 0.59 ) categories were inversely associated with the composite outcome of stroke/all-cause death . A similar inverse association was seen for the end point of stroke ( HR 0.61 and 0.47 , respectively ) . Good anticoagulation control also attenuated the association between BMI categories and outcomes . In patients with time in therapeutic range > 70 % , BMI category was not significantly associated with the composite outcome of stroke/death and stroke . Stroke and all-cause death progressively reduced in overweight and obese anticoagulated patients with AF . The inverse relation of BMI categories to the risk of stroke and all-cause death was mitigated by good anticoagulation control BACKGROUND Obesity is associated with the development of atrial fibrillation and may impact atrial fibrillation-related outcomes . To date , no anthropometric measure is included in any risk stratification scheme for stroke and death in atrial fibrillation patients . METHODS The prospect i ve Danish Diet , Cancer and Health study is a cohort including 57,053 participants ( 27,178 men and 29,875 women ) aged between 50 and 64 years . The study population for this study included the 3135 patients ( 2025 men and 1110 women ) who developed incident atrial fibrillation during follow-up . RESULTS Of the subjects with atrial fibrillation , 1414 ( 45 % ) had a body mass index ( BMI ) in the overweight category ( BMI 25 to < 30 kg/m(2 ) ) and 767 ( 24 % ) were categorized as obese ( BMI ≥30 kg/m(2 ) ) . During a median follow-up of 4.9 years , 609 deaths and 216 thromboembolic events ( 98 % ischemic strokes ) occurred . Using normal-weight patients as reference , the risk of a composite end point of " ischemic stroke , thromboembolism , or death " was significantly higher in overweight ( crude hazard ratio [ HR ] 1.31 ; 95 % confidence interval [ CI ] , 1.09 - 1.56 ) and obese patients ( crude HR 1.55 ; 95 % CI 1.27 - 1.90 ) . After adjustment for CHADS2 and CHA2DS2-VASc scores , the HRs for the composite end point were 1.21 ( 95 % CI 1.02 - 1.45 ) and 1.31 ( 95 % CI 1.10 - 1.56 ) , respectively , for overweight and 1.25 ( 95 % CI 1.03 - 1.53 ) and 1.36 ( 95 % CI 1.11 - 1.65 ) , respectively , for obese . Continuous analyses of BMI stratified by sex identified obese men and normal-weight women as the sex-specific " high-risk " categories . CONCLUSION Overweight and obesity are risk factors for " ischemic stroke , thromboembolism or death " in patients with atrial fibrillation , even after adjustment for CHADS2 and CHA2DS2-VASc scores . The association between BMI and outcomes among atrial fibrillation patients may be modified by sex Background Atrial fibrillation ( AF ) is the most common cardiac arrhythmia and is associated with increased risk of stroke and death . Obesity is an independent risk factor for AF , but modifiers of this risk are not well known . We studied the roles of obesity , physical activity , and their interaction in conferring risk of incident AF . Methods and Results The Women 's Health Initiative ( WHI ) Observational Study was a prospect i ve observational study of 93 676 postmenopausal women followed for an average of 11.5 years .  Incident AF was identified using WHI‐ascertained hospitalization records and diagnostic codes from Medicare cl aims . A multivariate Cox 's hazard regression model adjusted for demographic and clinical risk factors was used to evaluate the interaction between obesity and  physical activity and its association with incident AF . After exclusion of women with prevalent AF , incomplete data , or underweight body mass index ( BMI ) , 9792 of the remaining 81 317 women developed AF . Women were , on average , 63.4 years old , 7.8 % were African American , and 3.6 % were Hispanic .  Increased BMI ( hazard ratio [ HR ] , 1.12 per 5‐kg/m2 increase ; 95 % confidence interval [ CI ] , 1.10 to 1.14 ) and  reduced physical activity  ( > 9 vs. 0 metabolic equivalent task hours per week ; HR , 0.90 ; 95 % CI , 0.85 to 0.96 ) were independently associated with higher rates of AF after multivariate adjustment . Higher  levels of physical activity reduced the AF risk conferred by obesity ( interaction P=0.033 ) . Conclusions  Greater physical activity is associated with lower rates of incident AF and modifies the association between obesity and incident AF PURPOSE We examined the association between the body mass index analyzed as a continuous variable and by categorization according to World Health Organization criteria ( normal weight , overweight and obesity ) and the risk of a hospital ( inpatient as well as outpatient ) diagnosis of atrial fibrillation or flutter . METHODS Population -based prospect i ve cohort study conducted from December 1993 to December 2001 among 47589 participants ( 22482 men and 25107 women ) without preexisting cardiovascular or endocrine disease and with a mean age at baseline of 56 years ( range 50 - 64 years ) in the Danish Diet , Cancer , and Health Study . Subjects were followed up in the Danish National Registry of Patients and in the Danish Civil Registration System . RESULTS During follow-up ( mean , 5.7 years ) atrial fibrillation or flutter developed in 553 subjects ( 372 men and 181 women ) . The adjusted hazard ratio for atrial fibrillation or flutter per unit of increase in the body mass index was 1.08 ( 95 % confidence interval [ CI ] : 1.05 to 1.11 ) in men and 1.06 ( 95 % CI : 1.03 to 1.09 ) in women . When using normal weight as a reference , the adjusted hazard ratio for atrial fibrillation or flutter by overweight was 1.75 ( 95 % CI : 1.35 to 2.27 ) in men and 1.39 ( 95 % CI : 0.99 to 1.94 ) in women . The adjusted hazard ratio by obesity was 2.35 ( 95 % CI : 1.70 to 3.25 ) in men and 1.99 ( 95 % CI : 1.31 to 3.02 ) in women . CONCLUSION Overweight and obesity are associated with an increased risk of a diagnosis of atrial fibrillation or flutter Purpose Obesity influences risk stratification in cardiac surgery in everyday practice . However , some studies have reported better outcomes in patients with a high body mass index ( BMI ): this is known as the obesity paradox . The aim of this study was to quantify the effect of diverse degrees of high BMI on clinical outcomes after cardiac surgery , and to assess the existence of an obesity paradox in our patients . Methods A total of 2,499 consecutive patients requiring all types of cardiac surgery with cardiopulmonary bypass between January 2004 and February 2009 were prospect ively studied at our institution . Patients were divided into four groups based on BMI : normal weight ( 18.5–24.9 kg∙m−2 ; n = 523 ; 21.4 % ) , overweight ( 25–29.9kg∙m−2 ; n = 1150 ; 47 % ) , obese ( ≥30–≤34.9kg∙m−2 ; n = 624 ; 25.5 % ) and morbidly obese ( ≥35kg∙m−2 ; n = 152 ; 6.2 % ) . Follow-up was performed in 2,379 patients during the first year . Results After adjusting for confounding factors , patients with higher BMI presented worse oxygenation and better nutritional status , reflected by lower PaO2/FiO2 at 24h and higher albumin levels 48h after admission respectively . Obese patients showed a higher risk for Perioperative Myocardial Infa rct ion ( OR : 1.768 ; 95 % CI : 1.035–3.022 ; p = 0.037 ) and septicaemia ( OR : 1.489 ; 95 % CI : 1.282–1.997 ; p = 0.005 ) . In-hospital mortality was 4.8 % ( n = 118 ) and 1-year mortality was 10.1 % ( n = 252 ) . No differences were found regarding in-hospital mortality between BMI groups . The overweight group showed better 1-year survival than normal weight patients ( 91.2 % vs. 87.6 % ; Log Rank : p = 0.029 . HR : 1.496 ; 95 % CI : 1.062–2.108 ; p = 0.021 ) . Conclusions In our population , obesity increases Perioperative Myocardial Infa rct ion and septicaemia after cardiac surgery , but does not influence in-hospital mortality . Although we found better 1-year survival in overweight patients , our results do not support any protective effect of obesity in patients undergoing cardiac surgery OBJECTIVE To examine the effect of reverse causality and confounding on the association of BMI with all-cause and cause-specific mortality . RESEARCH METHODS AND PROCEDURES Data from two large prospect i ve studies were used . One ( a community-based cohort ) included 8327 women and 7017 men who resided in two Scottish towns at the time of the baseline assessment in 1972 - 1976 ; the other ( an occupational cohort ) included 4016 men working in the central belt of Scotl and at the time of the baseline assessment in 1970 - 1973 . Participants in both cohorts were ages 45 to 64 years at baseline ; the follow-up period was 28 to 34 years . RESULTS In age-adjusted analyses that did not take account of reverse causality or smoking , there was no association between being overweight ( BMI 25 to < 30 kg/m(2 ) ) and mortality , and weak to modest associations between obesity ( BMI > or = 30 kg/m(2 ) ) and mortality . There was a strong association between smoking and lower BMI in women and men in both cohorts ( all p < 0.0001 ) . Among never-smokers and with the first 5 years of deaths removed , overweight was associated with an increase in all-cause mortality ( relative risk ranging from 1.12 to 1.38 ) , and obesity was associated with a doubling of risk in men in both cohorts ( relative risk , 2.10 and 1.96 , respectively ) and a 60 % increase in women ( relative risk , 1.56 ) . In both never-smokers and current smokers , being overweight or obese was associated with important increases in the risk of cardiovascular disease . DISCUSSION These findings demonstrate that with appropriate control for smoking and reverse causality , both overweight and obesity are associated with important increases in all-cause and cause-specific mortality , and in particular with cardiovascular disease mortality INTRODUCTION Obesity has been described as a risk factor for the development of coronary artery disease , but it has not been determined whether obesity is associated with adverse outcomes after cardiac surgery . Therefore , we analyzed a large cohort of patients who had undergone cardiac surgery to determine whether obesity is a predictor of mortality , morbidity or early readmission to hospital . METHODS At the London Health Sciences Centre , an academic tertiary care centre , we prospect ively entered data from the cardiac surgical data base from July 1999 to April 2002 . We collected data on 1310 consecutive , unselected patients who underwent cardiac surgery during that time . We assessed the degree of obesity using the body mass index ( BMI ) , and we prospect ively documented the occurrence of 10 major complications after surgery . They included stroke , reoperation for bleeding , life-threatening cardiac arrest or arrhythmia , new renal failure requiring dialysis , septicemia , mediastinitis , sternal dehiscence , respiratory failure , postoperative myocardial infa rct ion and low cardiac output necessitating intra-aortic balloon pump use . Univariable and multivariable analyses were conducted to determine the factors associated with and predictive of postoperative death and major complications . RESULTS An increased BMI did not increase the risk of early postoperative death . Furthermore , increased BMI was not a predictor of a patient experiencing any of the major complications , except sternal dehiscence . An increased BMI was associated with a higher likelihood of readmission to hospital within 30 days of discharge . CONCLUSION Obesity was not associated with adverse outcomes after cardiac operations , aside from the increased risks of sternal dehiscence and early hospital readmission Atrial fibrillation and obesity are two major growing epidemics in the United States and globally . Obese people are at the increased risk of developing atrial fibrillation . The contribution of obesity as an independent risk factor for stroke in the setting of atrial fibrillation remains unclear . We tested the hypothesis that non-valvular atrial fibrillation ( NVAF ) patients with increased body mass index ( BMI ) would be at increased risk for the development of left atrial appendage thrombus ( LAAT ) .  Consecutive , anticoagulation naïve patients with NVAF referred for a transesophageal echocardiogram ( TEE ) between January 1 , 2007 and October 21 , 2009 were approached for study participation . All clinical , laboratory , and TEE measurement data were collected prospect ively . Within a group of 400 anticoagulation naïve NVAF patients ( mean age 63 ± 15 years , 28 % women ; 17 % with LAAT )  the prevalence of LAAT was similar across all BMI categories ( normal 13 % , overweight 19 % , obese 16 % , morbidly obese 16 % ; p = 0.71 ) . Despite a higher CHADS2 score and a higher prevalence of both hypertension and diabetes mellitus , elevated BMI was not an independent predictor of LAAT when analyzed as either a continuous variable , across BMI WHO categories , a dichotomous variable stratified at values above versus below 27 kg/m2 , or BMI stratified on atrial fibrillation duration . Despite a higher prevalence of major risk factors for thromboembolism , the prevalence of LAAT was not increased in overweight , obese , and morbidly obese patients Obesity is an escalating global health problem associated with both an increased risk of death and an increased risk of cardiovascular events . Our goal was to use magnetic resonance imaging ( MRI ) to determine the effect of obesity and weight loss , in the absence of the traditional cardiovascular risk factors , on aortic pulse wave velocity ( PWV ) a reliable , reproducible , and accurate clinical measure of aortic stiffness linked to increased mortality . Fifty obese ( BMI 38.3 ± 6.8 kg/m(2 ) ) and eighteen normal-weight controls ( BMI 22.0 ± 1.7 kg/m(2 ) ) with no identifiable cardiovascular risk factors underwent  vascular MRI  to assess PWV between the ascending aorta at the level of the pulmonary artery and the abdominal aorta ( AA ) . Twenty-eight subjects underwent repeat imaging after a 1-year period of weight loss . Both groups were well matched for age , systolic blood pressure , fasting glucose , and total cholesterol . Obesity was associated with a 14 % increase in PWV ( P = 0.021 ) , and with elevated C-reactive protein ( CRP ) ( P < 0.01 ) and leptin levels ( P < 0.001 ) factors known to cause increase arterial stiffness . Weight loss ( average 50 % excess weight ) was associated with a 14 % improvement in PWV ( P = 0.03 ) , and with reductions in serum leptin levels ( P < 0.01 ) . Obesity , in the absence of the traditional cardiovascular risk factors , is associated with increased aortic PWV , a noninvasive clinical measure of aortic stiffness independently predictive of cardiovascular mortality . Significant weight loss results in improvements in aortic PWV . This may provide a potential link between both obesity and increased mortality , and the reduction in mortality that occurs with weight loss PURPOSE An obesity paradox , a " paradoxical " decrease in morbidity and mortality with increasing body mass index ( BMI ) , has been shown in patients with heart failure and those undergoing percutaneous coronary intervention . However , whether this phenomenon exists in patients with hypertension and coronary artery disease is not known . METHODS A total of 22,576 hypertensive patients with coronary artery disease ( follow-up 61,835 patient years , mean age 66+/-9.8 years ) were r and omized to a verapamil-SR or atenolol strategy . Dose titration and additional drugs ( tr and olapril and /or hydrochlorothiazide ) were added to achieve target blood pressure control according to the Sixth Joint National Committee on Prevention , Detection , Evaluation , and Treatment of High Blood Pressure targets . Patients were classified into 5 groups according to baseline BMI : less than 20 kg/m2 ( thin ) , 20 to 25 kg/m2 ( normal weight ) , 25 to 30 kg/m2 ( overweight ) , 30 to 35 kg/m2 ( class I obesity ) , and 35 kg/m2 or more ( class II-III obesity ) . The primary outcome was first occurrence of death , nonfatal myocardial infa rct ion , or nonfatal stroke . RESULTS With patients of normal weight ( BMI 20 to<25 kg/m2 ) as the reference group , the risk of primary outcome was lower in the overweight patients ( adjusted hazard ratio [ HR ] 0.77 , 95 % confidence interval [ CI ] , 0.70 - 0.86 , P<.001 ) , class I obese patients ( adjusted HR 0.68 , 95 % CI , 0.59 - 0.78 , P<.001 ) , and class II to III obese patients ( adjusted HR 0.76 , 95 % CI , 0.65 - 0.88 , P < .001 ) . Class I obese patients had the lowest rate of primary outcome and death despite having smaller blood pressure reduction compared with patients of normal weight at 24 months ( -17.5+/-21.9 mm Hg/-9.8+/-12.4 mm Hg vs -20.7+/-23.1 mm Hg /-10.6+/-12.5 mm Hg , P<.001 ) . CONCLUSION In a population with hypertension and coronary artery disease , overweight and obese patients had a decreased risk of primary outcome compared with patients of normal weight , which was driven primarily by a decreased risk of all-cause mortality . Our results further suggest a protective effect of obesity in patients with known cardiovascular disease in concordance with data in patients with heart failure and those undergoing percutaneous coronary intervention Aims We have investigated the role of muscle mass , natriuretic peptides and adipokines in explaining the obesity paradox . Background The obesity paradox relates to the association between obesity and increased survival in patients with coronary heart disease ( CHD ) or heart failure ( HF ) . Methods Prospect i ve study of 4046 men aged 60–79 years followed up for a mean period of 11 years , during which 1340 deaths occurred . The men were divided according to the presence of doctor diagnosed CHD and HF : ( i ) no CHD or HF ii ) , with CHD ( no HF ) and ( iii ) with HF . Results Overweight ( BMI 25–9.9 kg/m2 ) and obesity ( BMI ≥ 30 kg/m2 ) were associated with lower mortality risk compared to men with normal weight ( BMI 18.5–24.9 kg/m2 ) in those with CHD [ hazards ratio ( HR ) 0.71 ( 0.56,0.91 ) and 0.77 ( 0.57,1.04 ) ; p = 0.04 for trend ] and in those with HF [ HR 0.57 ( 0.28,1.16 ) and 0.41 ( 0.16,1.09 ; p = 0.04 for trend ) . Adjustment for muscle mass and NT-proBNP attenuated the inverse association in those with CHD ( no HF ) [ HR 0.78 ( 0.61,1.01 ) and 0.96 ( 0.68,1.36 ) p = 0.60 for trend ) but made minor differences to those with HF [ p = 0.05 ] . Leptin related positively to mortality in men without HF but inversely to mortality in those with HF ; adjustment for leptin abolished the BMI mortality association in men with HF [ HR 0.82 ( 0.31,2.20 ) and 0.99 ( 0.27,3.71 ) ; p = 0.98 for trend ] . Conclusion The lower mortality risk associated with excess weight in men with CHD without HF may be due to higher muscle mass . In men with HF , leptin ( possibly reflecting cachexia ) explain the inverse association Background —Physical activity ( PA ) has previously been suggested to attenuate the risk of atrial fibrillation ( AF ) conferred by excess body weight and weight gain . We prospect ively examined the relationship between body size , weight change , and level of PA in a biracial cohort of middle-aged men and women . Methods and Results —Baseline characteristics on risk factor levels were obtained on 14 219 participants from the Atherosclerosis Risk in Communities Study . AF incidence was ascertained from 1987 to 2009 . Adjusted Cox proportional hazards models were used to estimate the associations between body mass index , waist circumference , relative weight change , and PA level with incident AF . During follow-up , there were 1775 cases of incident AF . Body mass index and waist circumference were positively associated with AF as was weight loss/gain of > 5 % initial body weight . An ideal level of PA had a small protective effect on AF risk and partially attenuated the risk of AF associated with excess weight in men but not women : compared with men with a normal body mass index , the risk of AF in obese men with an ideal , intermediate , and poor level of PA at baseline was increased by 37 % , 129 % , and 156 % ( Pinteraction=0.04 ) . During follow-up , PA did not modify the association between weight gain and risk of AF . Conclusions —Obesity and extreme weight change are risk factors for incident AF , whereas being physically active is associated with a small reduction in risk . In men only , being physically active offset some , but not all , of the risk incurred with excess body weight Background : Although obesity is an established risk factor for coronary heart disease and stroke mortality , its role as a risk factor for other causes of death has not been extensively investigated , particularly in an industrial population . Methods : This prospect i ve mortality study included 20 years of follow up of middle-aged industrial workers ( n = 7139 ) at Shell Oil Company 's manufacturing and research facilities . Baseline health risk factor data as of December 31 , 1983 , and mortality data as of December 31 , 2003 , were extracted from the company 's Health Surveillance System . Relative risks ( RRs ) for selected causes of death by body mass index ( BMI ) category were calculated using the Cox proportional hazards model adjusted for age , sex , and smoking status as well as other potential risk factors , ie , cholesterol , hypertension , and fasting blood glucose . Results : Compared with employees with BMI between 18.5 and 24.9 kg/m2 , those with BMI of 30 kg/m2 or greater had a statistically increased RR ( adjusted for age , sex , and smoking status ) for all causes ( RR , 1.25 ; 95 % confidence interval [ CI ] = 1.03–1.51 ) , coronary heart diseases ( RR , 2.29 ; 95 % CI = 1.50–3.50 ) , cardiovascular diseases ( RR , 2.22 ; 95 % CI = 1.51–3.27 ) , diabetes ( RR , 16.97 ; 95 % CI = 2.11–136.44 ) , and accidental deaths ( RR , 2.64 ; 95 % CI = 1.23–5.66 ) . After adjusting for additional covariates , coronary heart diseases and cardiovascular diseases remained statistically significant . Conclusions : Obesity was associated with increased death rates for all causes , cardiovascular diseases , diabetes , and all accidents . Overweight individuals had a statistically lower cancer rate . Death rates for lung cancer and respiratory disease were lower among overweight/obese employees but did not reach statistical significance . Reductions of employee obesity can be an effective means of reducing these causes of death OBJECTIVE A high body mass index has been suggested to be protective in patients with coronary artery disease and in those undergoing coronary artery bypass grafting ( CABG ) .  However , these conflicting results might be related to the different risk profiles among the various body mass index categories . We sought to clarify the effect of varying degrees of excessive body weight on hard clinical outcomes in patients undergoing CABG .  METHODS A retrospective analysis of prospect ively collected data was conducted to investigate the effect of a high body mass index on early and late mortality after  first-time isolated CABG . Propensity score matching was used to adjust for confounding factors . RESULTS The study sample consisted of 3269 normal weight , 6662 overweight , 3821 obese , and 211 morbidly obese patients . After matching , early mortality was not affected by overweight ( mean difference , 0.7 % ; 95 % confidence interval [ CI ] , -0.2 % to 1.5 % ) , obesity ( mean difference , 0.5 % ; 95 % CI , -0.7 % to 1.7 % ) , and morbid obesity ( mean difference , 1.6 % ; 95 % CI , -1.0 % to 1.0 % ) , regardless of the patients ' risk profile according to the European system for cardiac operative risk evaluation . Overweight status was not protective for late death ( hazard ratio , 1.05 ; 95 % CI , 0.9 - 1.08 ; P = .4 ) . Compared with normal weight patients , both obese and morbidly obese patients had a higher risk of late death ( hazard ratio , 1.22 ; 95 % CI , 1.07 - 2.66 ; P = .006 for obese patients ; hazard ratio , 1.36 ; 95 % CI , 0.74 - 2.49 ; P = .3 for morbidly obese patients ) . CONCLUSIONS Obesity did not increase operative mortality , but it was associated with reduced late survival in patients undergoing primary isolated CABG . Our results raise concerns in supporting any protective effect of obesity in cardiovascular disease , specifically in patients undergoing surgical myocardial revascularization AIMS Obesity is a recognized risk factor for  atrial fibrillation ( AF ) , partly because of the association between body mass index ( BMI ) and atrial volume . We aim ed to determine whether other factors relating to body size were related to AF . METHODS AND RESULTS Data were derived from a r and om population sample of 6903 men ( mean age 51.5 years ) who underwent a single midlife evaluation as part of the multifactor Swedish Primary Prevention Study . A total of 1253 men ( 18.2 % ) had a subsequent hospital discharge diagnosis ( principal or secondary ) of AF during a maximum follow-up of 34.3 years . Body surface area ( BSA ) at age 20 ( calculated from recalled weight and measured height ) was strongly related to subsequent AF ( P < 0.0001 ) , as were midlife BMI and weight gain from age 20 to midlife ( P < 0.0001 ) . In a Cox regression model which adjusted for midlife BMI , weight gain and other risk factors , hazard ratios ( HR ) [ 95 % confidence intervals ( CI ) ] for AF for the second , third , and fourth quartile of BSA at age 20 , compared with the lowest quartile , were 1.47 ( 95 % CI , 1.22 - 1.76 ) , 1.66 ( 95 % CI , 1.38 - 2.00 ) , and 2.22 ( 95 % CI , 1.82 - 2.70 ) ( P for trend < 0.0001 ) . CONCLUSION Large body size in youth , in an era when obesity was rare , as well as weight gain from age 20 to midlife , were both independently related to the development of AF . Given the current trends not only for obesity but also for height , a substantial increase in the incidence of AF is likely
Results — An obesity paradox was found for cardiovascular death and all-cause death in the subgroup analyses of r and omized trial cohorts ; however , observational studies fail to show this relationship .
Conclusions — There may be an obesity paradox in atrial fibrillation patients , particularly for all-cause and cardiovascular death outcomes .
An obesity paradox was also evident for stroke/systemic embolic event outcome in NOAC trials , with a treatment effect favoring NOACs over warfarin for both efficacy and safety that was significant only for normal weight patients
Background and Purpose — Obesity is a risk factor for all-cause and cardiovascular death but , despite this , an inverse relationship between overweight or obesity and a better cardiovascular prognosis in long-term follow-up studies has been observed ; this phenomenon , described as obesity paradox , has also been found evident in atrial fibrillation cohorts .
Methods — We performed a systematic review on the relationship between body mass index and major adverse outcomes in atrial fibrillation patients .