Relation of body mass index to late survival after valvular heart surgery

Mechanisms of myocardial reverse remodelling and its clinical significance: A scientific statement of the ESC Working Group on Myocardial Function

Cardiovascular disease (CVD) is the leading cause of morbimortality in Europe and worldwide. CVD imposes a heterogeneous spectrum of cardiac remodelling, depending on the insult nature, that is, pressure or volume overload, ischaemia, arrhythmias, infection, pathogenic gene variant, or cardiotoxicity. Moreover, the progression of CVD-induced remodelling is influenced by sex, age, genetic background and comorbidities, impacting patients' outcomes and prognosis. Cardiac reverse remodelling (RR) is defined as any normative improvement in cardiac geometry and function, driven by therapeutic interventions and rarely occurring spontaneously. While RR is the outcome desired for most CVD treatments, they often only slow/halt its progression or modify risk factors, calling for novel and more timely RR approaches. Interventions triggering RR depend on the myocardial insult and include drugs (renin-angiotensin-aldosterone system inhibitors, beta-blockers, diuretics and sodium-glucose cotransporter 2 inhibitors), devices (cardiac resynchronization therapy, ventricular assist devices), surgeries (valve replacement, coronary artery bypass graft), or physiological responses (deconditioning, postpartum). Subsequently, cardiac RR is inferred from the degree of normalization of left ventricular mass, ejection fraction and end-diastolic/end-systolic volumes, whose extent often correlates with patients' prognosis. However, strategies aimed at achieving sustained cardiac improvement, predictive models assessing the extent of RR, or even clinical endpoints that allow for distinguishing complete from incomplete RR or adverse remodelling objectively, remain limited and controversial. This scientific statement aims to define RR, clarify its underlying (patho)physiologic mechanisms and address (non)pharmacological options and promising strategies to promote RR, focusing on the left heart. We highlight the predictors of the extent of RR and review the prognostic significance/impact of incomplete RR/adverse remodelling. Lastly, we present an overview of RR animal models and potential future strategies under pre-clinical evaluation.

Relation of body mass index to long-term survival and cardiac remodelling for patients undergoing mitral valve replacement surgery

BACKGROUND AND AIMS

Studies have demonstrated that obesity is paradoxically associated with reduced mortality following cardiac surgery. However, these studies have treated various types of cardiac surgery as a single entity. With mitral valve (MV) surgeries being the fastest-growing cardiac surgical interventions in North America, the purpose of this study was to identify the impact of body mass index (BMI) on long-term survival and cardiac remodelling of patients undergoing MV replacement (MVR).

METHODS AND RESULTS

In this retrospective, single-center study, 1071 adult patients who underwent an MVR between 2004 and 2018 were stratified into five BMI groups (<20, 20-24.9, 25-29.9, 30-34.9, >35). Cox proportional hazard regression models were used to determine the association between BMI and all-cause mortality. Patients who were underweight had significantly higher all-cause mortality rates at the longest follow-up (median 8.2 years) than patients with normal weight (p = 0.01). Patients who were in the obese group had significantly higher readmission rates due to myocardial infarction (MI) at the longest follow-up (p = 0.017). Subgroup analysis revealed a significant increase in long-term all-cause mortality for female patients who were underweight. Significant changes in left atrial size, mitral valve peak and mean gradients were seen in all BMI groups.

CONCLUSIONS

For patients undergoing mitral valve replacement, BMI is unrelated to operative outcomes except for patients who are underweight.

Midterm Outcomes of Underweight Patients Undergoing Transcatheter Aortic Valve Implantation: Insight From the LAPLACE-TAVR Registry

Background

Obesity is a major risk factor for cardiovascular disease; however, a paradoxical effect of obesity has been reported in patients with heart failure or myocardial infarction. Although several studies have suggested the same obesity paradox in patients undergoing transcatheter aortic valve replacement (TAVR), they included a limited number of underweight patients.

Objectives

This study aimed to clarify the effect of being underweight on TAVR outcomes.

Methods

We retrospectively analyzed 1,693 consecutive patients undergoing TAVR between 2010 and 2020. The patients were categorized according to body mass index: underweight (<18.5 kg/m²; n = 242), normal weight (18.5 to 25 kg/m²; n = 1,055), and overweight (>25 kg/m²; n = 396). We compared midterm outcomes after TAVR among the 3 groups; all clinical events were in accordance with the Valve Academic Research Consortium-2 criteria.

Results

Underweight patients were more likely to be women and have severe heart failure symptoms, peripheral artery disease, anemia, hypoalbuminemia, and pulmonary dysfunction. They also had lower ejection fractions, smaller aortic valve areas, and higher surgical risk scores. Device failure, life-threatening bleeding, major vascular complications, and 30-day mortality occurred more frequently in underweight patients. The midterm survival rate of the underweight group was inferior to those of the other 2 groups (P < 0.0001; average follow-up, 717 days). In the multivariate analysis, underweight was associated with noncardiovascular mortality (HR: 1.78; 95% CI: 1.16-2.75) but not cardiovascular mortality (HR: 1.28; 95% CI: 0.58-1.88) after TAVR.

Conclusions

Underweight patients had a worse midterm prognosis, demonstrating the obesity paradox in this TAVR population. (Outcomes of transcatheter aortic valve implantation in Japanese patients with aortic stenosis: multi-center registry; UMIN000031133).

Heart valve surgery and the obesity paradox: A systematic review

Obesity has been associated with increased incidence of comorbidities and shorter life expectancy, and it has generally been assumed that patients with obesity should have inferior outcomes after surgery. Previous literature has often demonstrated equivalent or even improved rates of mortality after cardiac surgery when compared to their lower-weight counterparts, coined the obesity paradox. Herein, we aim to review the literature investigating the impact of obesity on surgical valve interventions. PubMed and Embase were systematically searched for articles published from 1 January 2000 to 15 October 2021. A total of 1315 articles comparing differences in outcomes between patients of varying body mass index (BMI) undergoing valve interventions were reviewed and 25 were included in this study. Patients with higher BMI demonstrated equivalent or reduced rates of postoperative myocardial infarction, stroke, reoperation rates, acute kidney injury, dialysis and bleeding. Two studies identified increased rates of deep sternal wound infection in patients with higher BMI, although the majority of studies found no significant difference in deep sternal wound infection rates. The obesity paradox has described counterintuitive outcomes predominantly in coronary artery bypass grafting and transcatheter aortic valve replacement. Recent literature has identified similar trends in other heart valve interventions. While the obesity paradox has been well characterized, its causes are yet to be identified. Further study is essential in order to identify the causes of the obesity paradox so patients of all body sizes can receive optimal care.

Impact of body mass index on the outcome of elderly patients treated with transcatheter aortic valve implantation

Underweight or overweight patients with cardiovascular diseases are associated with different outcomes. However, the data on the relation between body mass index (BMI) and outcomes after transcatheter aortic valve implantation (TAVI) are not homogeneous. The aim of this study was to assess the role of low BMI on short and long-term mortality in real-world patients undergoing TAVI. We retrospectively included patients undergoing TAVI for severe aortic valve stenosis. Patients were classified into three BMI categories: underweight (< 20 kg/m²), normal weight (20-24.9 kg/m²) and overweight/obese (≥ 25 kg/m²). Our primary endpoint was long-term all-cause mortality. The secondary endpoint was 30-day all-cause mortality. A total of 794 patients were included [mean age 82.3 ± 5.3, 53% females]. After a median follow-up of 2.2 years, all-cause mortality was 18.1%. Patients in the lowest BMI group showed a higher mortality rate as compared to those with higher BMI values. At the multivariate Cox regression analysis, as compared to the normal BMI group, BMI < 20 kg/m² was associated with long-term mortality independently of baseline risk factors and postprocedural adverse events (hazard ratio [HR] 2.29, 95% confidence interval [CI] 1.30-4.03] and HR 2.61, 95% CI 1.48-4.60, respectively). The highest BMI values were found to be protective for both short- and long-term mortality as compared to lower BMI values even after applying the same adjustments. In our cohort, BMI values under 20 kg/m² were independent predictors of increased long-term mortality. Conversely, the highest BMI values were associated with lower mortality rates both at short- and long-term follow-up.

Impact of body mass index on early and mid-term outcomes after surgery for acute Stanford type A aortic dissection

Background

Obesity is dramatically increasing worldwide, and more obese patients may develop aortic dissection and present for surgical repair. The study aims to analyse the impact of body mass index (BMI) on surgical outcomes in patients with acute Stanford type A aortic dissection (ATAAD).

Methods

From January 2017 to June 2019, the clinical data of 268 ATAAD patients in a single centre were retrospectively reviewed. They were divided into three groups based on the BMI: normal weight (BMI 18.5 to < 25 kg/m², n = 110), overweight (BMI 25 to < 30 kg/m², n = 114) and obese (BMI ≥30 kg/m², n = 44).

Results

There was no statistical difference among the three groups in terms of the composite adverse events including 30-day mortality, stroke, paraplegia, renal failure, hepatic failure, reintubation or tracheotomy and low cardiac output syndrome (20.9% vs 21.9% vs 18.2% for normal, overweight and obese, respectively; P = 0.882). No significant difference was found in the mid-term survival among the three groups. The proportion of prolonged ventilation was highest in the obese group followed by the overweight and normal groups (59.1% vs 45.6% vs 34.5%, respectively; P = 0.017). Multivariable logistic regression analysis suggested that BMI was not associated with the composite adverse events, while BMI ≥30 kg/m² was an independent risk factor for prolonged ventilation (OR 2.261; 95% CI 1.056–4.838; P = 0.036).

Conclusions

BMI had no effect on the early major adverse outcomes and mid-term survival after surgery for ATAAD. Satisfactory surgical outcomes can be obtained in patients with ATAAD at all weights.

Contemporary Results of Transcatheter Aortic Valve Replacement in Obese Patients

Background. Little research has been conducted to explore the postoperative outcomes of obese patients after transfemoral transcatheter aortic valve replacement (TF-TAVR). Objective. We investigated the influence of body mass index (BMI) on 1-year outcomes after TF-TAVR. Methods. We included retrospectively 1609 high- and intermediate-risk TAVR patients (mean EuroSCORE II 21 ± 11) operated under general anesthesia between March 2014 and March 2018 in central hospital, Bad Berka, Germany. We stratified the patients according to BMI. Results. Our demographic data analysis showed 41% of patients were male and the mean age was 78 (range, 61–92 years). According to the WHO classification, 33% patients had normal weight, 42% were defined as overweight, and 22% were obese. Obese patients showed statistically significant difference in their clinical parameters as having higher incidence of hypertension, diabetes mellitus, pulmonary hypertension, and chronic obstructive pulmonary disease; on the contrary, obese patients were found to be younger than others. We found no differences in valve types and sizes among the different BMI categories. Our mortality rate during the 1-year follow-up period was 17.8% (287 patients). Mortality was significantly higher in patients with BMI < 25 kg/m2 (1 year mortality 149 patients 28.2% in patients with BMI < 25 kg/m2 vs. 138 patients 12.6% in patients with BMI ≥ 25 kg/m2; P=0.0001). Even after considering the confounding risk factors, BMI ≥ 25 kg/m2 was independently associated with reduced 1 year mortality (odds ratio (OR): 0.36, 95% confidence interval (CI): 0.21–0.6; P=0.01) in multivariate logistic regression analysis. The rate of vascular complication was higher in patients with BMI ≥ 25 kg/m2. However, the rate of blood transfusion was higher in patients with BMI < 25 kg/m2. All other serious complications occurred with equal distribution in both groups. Conclusion. In our single-center study, BMI ≥ 25 kg/m2 was independently associated with lower 1 year mortality after TF-TAVR.

The effects of body mass index on outcomes for patients undergoing surgical aortic valve replacement

Background

Most of the studies of obesity and postoperative outcome have looked predominantly at coronary artery bypass grafting with fewer focused on valvular disease. The purpose of this study was to compare the outcomes of patients undergoing aortic valve replacement stratified by body mass index (BMI, kg/m^2).

Methods

The Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease registry captured 4780 aortic valve replacements in Alberta, Canada from January 2004 to December 2018. All recipients were stratified by BMI into five groups (BMI: < 20, 20–24.9, 25–29.9, 30–34.9, and > = 35). Log-rank test and Cox regression were used to examine the crude and adjusted survival differences.

Results

Intra-operative clamp time and pump time were similar among the five groups. Significant statistical differences between groups existed for the incidence of isolated AVR, AVR and CABG, hemorrhage, septic infection, and deep sternal infection (p < 0.05). While there was no significant statistical difference in the mortality rate across the BMI groups, the underweight AVR patients (BMI < 20) were associated with increased hazard ratio (1.519; 95% confidence interval: 1.028–2.245) with regards to all-cause mortality at the longest follow-up compared with normal weight patients.

Conclusion

Overweight and obese patients should be considered as readily for AVR as normal BMI patients.

Association of body mass index and all-cause mortality in patients after cardiac surgery: A dose-response meta-analysis

Ample studies have reported the effect of body mass index (BMI) on the prognosis of patients undergoing cardiac surgery, but the results remain inconsistent. Therefore, we aimed to conduct a dose-response meta-analysis to clarify the relationship between BMI and all-cause mortality in this population. A systematic search was performed in the PubMed and Embase databases through April 2019 for studies that reported the impact of BMI on all-cause mortality in patients after cardiac surgery. Pooled risk ratios (RRs) were calculated using a random-effects model. Non-linear associations were explored with restricted cubic spline models. Forty-one studies with a total of 54,300 cases/1,774,387 patients were included. The pooled RR for all-cause mortality was 0.93 (95% CI 0.89-0.97) for every 5-unit increment in BMI, indicating that higher BMI did not increase the risk of all-cause mortality in patients after cardiac surgery. A U-shaped association with the nadir of risk at a BMI of 25-27.5 kg/m² was observed, as well as a higher mortality risk for the underweight and the extremely obese patients. The subgroup analysis revealed that this phenomenon remained regardless of mean age, surgery type, geographic location and number of cases. Overall, for patients after cardiac surgery, a slightly higher BMI may be instrumental in survival, whereas underweight and extreme obesity is associated with a worse prognosis.

Head and Neck Cancer Complications in the Geriatric Population Based on Hospital Case Volume

OBJECTIVE

To determine whether surgical case volume is a predictive factor of surgical outcomes when managing geriatric patients with head andneck cancer.

METHODS

A cross-sectional study design was used. Data were obtainedfrom the Vizient Database, which included a total of 93 academicinstitutions. Men and women aged between 65 and 100 years undergoing head and neck cancer surgery during 2009 and 2012,excluding cases of thyroid cancer and skin cancer of the head and neck(n = 4544) were included in the study. Hospital case volume was definedas low (≤21 cases/year), moderate (22-49 cases/year), or high (≥50 cases/year). The frequency of comorbidities and complications wasmeasured by hospital case volume using a χ² test. Significancewas determined with an α level of .05.

RESULTS

The largest number of head and neck cancer cases involving comorbidities (90.54%) and the highest rate of overall complications(27.50%) occurred in moderate case volume institutions compared to athe complication rate of 22.89% in low volume hospitals and 21.50% in highvolume hospitals (P < .0001). The most common comorbidities across all3 hospital case volumes included hypertension, metastatic cancer,and chronic pulmonary disease and the most common complicationsincluded hemorrhage/hematoma and postoperative pulmonarycompromise.

CONCLUSION

With more geriatric patients requiring surgery for head andneck cancer, it would be beneficial to manage the more complex cases at high volume centers and to develop multidisciplinary teams to optimizecase management and minimize complications.

Association Between Underweight Body Mass Index and In-Hospital Outcome in Patients Undergoing Endovascular Interventions for Peripheral Artery Disease: A Propensity Score Matching Analysis

PURPOSE

To investigate in-hospital outcomes after endovascular therapy (EVT) in patients with severe peripheral artery disease (PAD) who had a low body mass index (BMI, kg/m²) compared to those with normal BMI.

MATERIALS AND METHODS

Using weighted data from the National Inpatient Sample (NIS) database between 2002 and 2014 and ICD-9 codes, 2614 patients were identified who were aged ≥18 years and underwent EVT for PAD in the lower limb vessels. EVT was defined as angioplasty, atherectomy, and/or stenting. After excluding individuals with BMI >24, there were 807 (31%) normal-weight (BMI 19-24) patients and 1807 (69%) underweight (BMI <19) individuals. All patients in both groups were matched for baseline demographic and clinical characteristics and critical limb ischemia in a 1:1 propensity score matching analysis using the nearest neighbor method.

RESULTS

Propensity score matching produced 2 groups of 685 patients that differed only in the incidence of chronic lung disease, which was more frequent in low-BMI patients (p=0.04). Patients with low BMI had a higher incidence of in-hospital mortality (4.8% vs 1.2%, p<0.001), major adverse cardiovascular events (composite of death, myocardial infarction, or stroke) (7.9% vs 4.1%, p=0.003), open bypass surgery (9.1% vs 6.0%, p=0.03), and infection (14.6% vs 10.5%, p=0.02) compared with the normal-BMI group. There was no significant difference in the incidence of vascular complications (p=0.31), major bleeding (p=0.17), major amputation (p=0.35), or acute kidney injury (p=0.09) between the low- and normal-BMI groups.

CONCLUSION

Low-BMI patients with PAD have worse in-hospital survival and more adverse outcomes after EVT.

Impact of body mass index on outcomes following mitral surgery: does an obesity paradox exist?

OBJECTIVES

This study was conducted to clarify the relationship between body mass index and mitral valve (MV) surgery and to determine whether an 'obesity paradox' exists in the context of surgery for degenerative MV disease.

METHODS

In this retrospective single-centre study, we analysed data from 715 patients who underwent mitral surgery for degenerative disease from 2000 to 2015. Patients were classified according to body mass index: underweight (<20 kg/m2), normal weight (20-24.99 kg/m2), overweight (25-29.99 kg/m2) and obese (≥30 kg/m2). Early and long-term results were investigated. Multivariable analysis was conducted to identify risk factors for long-term mortality.

RESULTS

Mean follow-up was 67 ± 44 months (range 0-190 months). There were no differences between groups regarding 30-day mortality (P = 0.35), stroke (P = 0.45), reoperation for bleeding (P = 0.9) and length of hospital stay (P = 0.31). Obese patients were at increased risk of acute kidney injury when compared with normal weight patients (17% vs 5%; P = 0.03) but not when compared with the other groups; this was confirmed within the subgroup with depressed ejection fraction (42% vs 10%, P = 0.02). No differences in long-term survival were found across groups for all patients (P = 0.62) and for patients with depressed ejection fraction (P = 0.6), with a trend towards worse survival in obese patients undergoing MV repair (P = 0.06). Survival in obese patients undergoing repair was significantly worse than that in obese patients undergoing replacement (P = 0.04).

CONCLUSIONS

An 'obesity paradox' was not demonstrated after surgery for degenerative MV disease. Obese patients are more prone to acute kidney injury and have worse late survival after MV repair.

Impact of Body Mass Index on Short- and Long-Term Outcomes After Isolated First-Time Surgical Aortic Valve Replacement for Aortic Stenosis

OBJECTIVE

To ascertain whether body mass index (BMI) has a clinical effect on short- and long-term postoperative outcomes after surgical aortic valve replacement in patients with severe aortic stenosis.

DESIGN

Single-center, retrospective study.

SETTING

Tertiary referral hospital.

PARTICIPANTS

The study comprised 1,561 patients who underwent isolated first-time aortic valve replacement between 2005 and 2012.

INTERVENTIONS

Fourteen underweight patients were removed from the analysis. The remaining patients were divided into the following 4 groups according to their BMI: 418 as normal weight (≥18.5 to <25 kg/m²), 629 as overweight (≥25 to <30 kg/m²), 342 as obese (≥30 to <35 kg/m²), and 158 as very obese (≥35 kg/m²). Early mortality and postoperative complications were compared, and long-term survival rates were investigated.

MEASUREMENT AND MAIN RESULTS

Thirty-day mortality was higher in the normal weight group but did not reach statistical significance (p = 0.054), and the incidence of postoperative complications was not different for cerebrovascular accident (p = 0.70), re-sternotomy for bleeding (p = 0.17), sternal wound infection (p = 0.07), and dialysis (p = 0.07). With a mean follow-up time of 4.92 ± 2.82 years, survival rate was better in the overweight group. A Cox proportional hazard model found BMI inversely correlated with long-term mortality when analyzed in a univariable fashion (hazard ratio 0.95; p = 0.009), but this apparent protective effect disappeared when adjusted for preoperative covariates (hazard ratio 0.98, 95% confidence interval 0.96-1.004; p = 0.12).

CONCLUSION

Once adjusted for preoperative characteristics, obesity does not represent an independent predictor for long-term survival rates. There was a higher incidence of 30-day mortality in the normal weight group compared with the overweight and very obese groups. The incidence of deep sternal wound infection was higher in very obese patients.

Influence of Body Mass Index on Outcomes of Patients Undergoing Surgery for Acute Aortic Dissection: A Propensity-Matched Analysis

To determine whether body mass index ≥30 kg/m² affects morbidity and mortality rates in patients undergoing surgery for type A acute aortic dissection, we conducted a retrospective study of 201 patients with type A dissection. Patients were divided into 2 groups according to body mass index (BMI): nonobese (BMI, <30 kg/m²; 158 patients) and obese (BMI, ≥30 kg/m²; 43 patients). Propensity score matching was used to reduce selection bias. The overall mortality rate was 19% (38/201 patients). The perioperative mortality rate was higher in the obese group, both in the overall cohort (33% vs 15%; P=0.01) and in the propensity-matched cohort (32% vs 12%; P=0.039). In the propensity-matched cohort, patients with obesity had higher rates of low cardiac output syndrome (26% vs 6%; P=0.045) and pulmonary complications (32% vs 9%; P=0.033) than those without obesity. The overall 5-year survival rates were 52.5% ± 7.8% in the obese group and 70.3% ± 4.4% in the nonobese group (P=0.036). In the propensity-matched cohort, the 5-year survival rates were 54.3% ± 8.9% in the obese group and 81.6% ± 6.8% in the nonobese group (P=0.018). Patients with obesity (BMI, ≥30 kg/m²) who underwent surgery for type A acute aortic dissection had higher operative mortality rates and an increased risk of low cardiac output syndrome, pulmonary complications, and other postoperative morbidities than did patients without obesity. Additional extensive studies are needed to confirm our findings.

Perioperative Care of the Obese Cardiac Surgical Patient

Morbid obesity is associated with impairment of cardiovascular, pulmonary, gastrointestinal, and renal physiology with significant perioperative consequences and has been linked with higher morbidity and mortality after cardiac surgery. Cardiac surgery patients have a higher incidence of difficult airway and difficult laryngoscopy than general surgery patients do, and obesity is associated with difficult mask ventilation and direct laryngoscopy. Positioning injuries occur more frequently because obese patients are at greater risk of pressure injury, such as rhabdomyolysis and compartment syndrome. Despite the association between obesity and several chronic disease states, the effects of obesity on perioperative outcomes are conflicting. Studies examining outcomes of overweight and obese patients in cardiac surgery have reported varying results. An "obesity paradox" has been described, in which the mortality for overweight and obese patients is lower compared with patients of normal weight. This review describes the physiologic abnormalities and clinical implications of obesity in cardiac surgery and summarizes recommendations for anesthesiologists to optimize perioperative care of the obese cardiac surgical patient.

Preoperative Nutritional Status and Clinical Complications in the Postoperative Period of Cardiac Surgeries

Objective

This study aims to assess the preoperative nutritional status of patients and the role it plays in the occurrence of clinical complications in the postoperative period of major elective cardiac surgeries.

Methods

Cross-sectional study comprising 72 patients aged 20 years or older, who underwent elective cardiac surgery. The preoperative nutritional assessment consisted of nutritional screening, anthropometry (including the measurement of the adductor pollicis muscle thickness) and biochemical tests. The patients were monitored for up to 10 days after the surgery in order to control the occurrence of postoperative complications. The R software, version 3.0.2, was used to statistically analyze the data.

Results

Clinical complications were found in 62.5% (n=42) of the studied samples and complications of non-infectious nature were most often found. Serum albumin appeared to be associated with renal complications (P=0.026) in the nutritional status indicators analyzed herein. The adductor pollicis muscle thickness was associated with infectious complications and presented mean of 9.39±2.32 mm in the non-dominant hand (P=0.030). No significant correlation was found between the other indicators and the clinical complications.

Conclusion

The adductor pollicis muscle thickness and the serum albumin seemed be associated with clinical complications in the postoperative period of cardiac surgeries.

Body Mass Index and Mortality Among Adults Undergoing Cardiac Surgery: A Nationwide Study With a Systematic Review and Meta-Analysis

BACKGROUND

In an apparent paradox, morbidity and mortality are lower in obese patients undergoing cardiac surgery, although the nature of this association is unclear. We sought to determine whether the obesity paradox observed in cardiac surgery is attributable to reverse epidemiology, bias, or confounding.

METHODS

Data from the National Adult Cardiac Surgery registry for all cardiac surgical procedures performed between April 2002 and March 2013 were extracted. A parallel systematic review and meta-analysis (MEDLINE, Embase, SCOPUS, Cochrane Library) through June 2015 were also accomplished. Exposure of interest was body mass index categorized into 6 groups according to the World Health Organization classification.

RESULTS

A total of 401 227 adult patients in the cohort study and 557 720 patients in the systematic review were included. A U-shaped association between mortality and body mass index classes was observed in both studies, with lower mortality in overweight (adjusted odds ratio, 0.79; 95% confidence interval, 0.76-0.83) and obese class I and II (odds ratio, 0.81; 95% confidence interval, 0.76-0.86; and odds ratio, 0.83; 95% confidence interval, 0.74-0.94) patients relative to normal-weight patients and increased mortality in underweight individuals (odds ratio, 1.51; 95% confidence interval, 1.41-1.62). In the cohort study, a U-shaped relationship was observed for stroke and low cardiac output syndrome but not for renal replacement therapy or deep sternal wound infection. Counter to the reverse epidemiology hypotheses, the protective effects of obesity were less in patients with severe chronic renal, lung, or cardiac disease and greater in older patients and in those with complications of obesity, including the metabolic syndrome and atherosclerosis. Adjustments for important confounders did not alter our results.

CONCLUSIONS

Obesity is associated with lower risks after cardiac surgery, with consistent effects noted in multiple analyses attempting to address residual confounding and reverse causation.

Prognostic value of body mass index and body surface area on clinical outcomes after transcatheter aortic valve implantation

BACKGROUND

Inverse associations between Body Mass Index (BMI) and Body Surface Area (BSA) with mortality in patients after Transcatheter Aortic Valve Implantation (TAVI) have been reported. This "obesity paradox" is controversial, and it remains unclear which parameter, BMI or BSA, is of greater prognostic value. The aim of this study was to investigate the association of BMI and BSA on short- and mid-term outcomes after TAVI.

METHODS AND RESULTS

This prospective, observational study consisted of 917 consecutive patients undergoing TAVI at our center from 2011 to 2014. The association between BMI/BSA and mortality (at 30 days and 1 year) was assessed using restricted cubic spline functions in propensity-adjusted (by Society of Thoracic Surgeons (STS) risk factors) logistic and Cox proportional models, respectively. The median age of the patients was 82.6 years, with a mean STS Predicted Risk of Mortality (STS-PROM) of 6.6 ± 4.3 %. Throughout the study period (mean follow-up time was 297 days), 150 (16.4 %) patients died; 72 (7.9 %) patients died within 30 days of TAVI. After risk adjustment, the association between body constitution and 30-day mortality was not significant for either measure (BMI p = 0.25; BSA p = 0.32). However, BMI (p = 0.01), but not BSA (p = 0.13), was significantly associated with 1-year survival. There was no association between stroke, vascular complications, or length of stay with BMI or BSA.

CONCLUSIONS

BMI was associated with survival at 1-year after TAVI. Despite the trend towards implementing BSA in risk score calculation, BMI may be more suitable for the assessment of TAVI patients.

Impact of transfemoral versus transapical access on mortality among patients with severe aortic stenosis undergoing transcatheter aortic valve replacement

OBJECTIVE

To compare early and late mortality of transfemoral (TF) and transapical (TA) transcatheter aortic valve replacement (TAVR) patients and assess predictors for mortality.

BACKGROUND

Studies have shown conflicting results regarding impact of access on outcome in severe aortic stenosis (AS) patients undergoing TAVR.

METHODS

AS patients undergoing TAVR between May 2007-December 2014 were included. Baseline demographic, clinical, and imaging parameters were compared according to access, and landmark analysis models were generated to assess outcomes and associated factors.

RESULTS

Among 648 severe AS patients undergoing TAVR, TF was used in 516 and TA in 132. Baseline characteristics between groups demonstrated lower body mass index, higher STS score, and rate of peripheral vascular disease among TA patients. Procedural complications were more common in the TA group, especially major bleeding (15% vs. 6%, p<0.001) and acute kidney injury >1 (8% vs. 1.4%, p<0.001). Landmark analysis demonstrated higher cumulative mortality rates at 30days among TA than TF patients (log-rank p<0.001), with similar mortality after 30days and up to 1-year (13% in both log-rank p=0.64). In a multivariate model, TA was an independent predictor of early mortality (HR=4.55 95% CI [12.5-1.6], p=0.003) along with pulmonary artery systolic pressure>60mmHg (HR=3.08 95% CI [7.37-1.29], p=0.01) and residual aortic regurgitation severity above mild (HR=3.99 95% CI [10.2-1.56], p=0.004).

CONCLUSIONS

Patients undergoing TAVR via TA have higher adjusted early mortality and similar late mortality rates compared to TF, despite higher risk profile.

Impact of body mass index on outcome in patients undergoing coronary artery bypass grafting and/or valve replacement surgery

Objective

This study aimed to analyze the impact of body mass index on outcomes of 101 patients undergoing coronary artery bypass grafting, valve replacement, or combined valve/ coronary artery bypass grafting surgery in a private hospital in Belo Horizonte, Brazil.

Methods

This was a prospective cross-sectional study of patients undergoing cardiac surgery from May 2009 to December 2012. All patients were followed up from the first day of admission until discharge or death. Patients were divided into three groups according to BMI: normal weight, overweight, and obese. The main outcome measure was the association between BMI and postoperative morbidities and mortality.

Results

Multivariate analysis identified obesity as an independent predictor of increased risk of surgical reintervention (odds ratio [OR] 13.6; 95%CI 1.1 - 162.9; P=0.046) and reduced risk of bleeding (OR 0.05; 95% CI 0.09 - 0.69; P=0.025). Univariate analysis showed that obesity was associated with increased frequency of wound dehiscence (P=0.021). There was no association between BMI and other complications or mortality in univariate analysis. There was also no association between body mass index and duration of cardiopulmonary bypass, aortic clamping, mechanical ventilation, and intensive care unit or hospital stay.

Conclusion

Obese individuals undergoing coronary artery bypass grafting, valve replacement, or combined surgery have a higher postoperative risk of surgical reintervention and lower chances of bleeding.

Impact of Body Mass Index on Outcomes in Cardiac Surgery

OBJECTIVES

Body mass index (BMI) commonly is used in obesity classification as a surrogate measure, and obesity is associated with a cluster of risk factors for cardiovascular disease. The aim of this study was to investigate the impact of BMI on short-term outcomes after cardiac surgery.

DESIGN

A retrospective cohort study.

SETTING

University teaching hospital, 2 centers.

PARTICIPANTS

The study comprised 4,740 patients who underwent cardiac surgery at 2 hospitals-from July 1, 2001, to June 30, 2013, in 1 hospital and from September 1, 2003, to August 31, 2014, in a second hospital.

INTERVENTIONS

No changes to standard practice were required.

MEASUREMENTS AND MAIN RESULTS

Patients were assigned into 6 BMI groups as follows: underweight (BMI<18.5 kg/m(2)), normal weight (≥18.5 to<25 kg/m(2)), overweight (≥25 to<30 kg/m(2)), class I obese (≥30 to<35 kg/m(2)), class II obese (≥35 to<40 kg/m(2)), and class III obese (BMI≥40 kg/m(2)). Short-term major postoperative complications (postoperative stroke, cardiac arrest, new atrial fibrillation/flutter, permanent rhythm device insertion, deep sternal infection, sepsis, prolonged ventilation, pneumonia, renal dialysis, renal failure, intensive care unit readmission, total intensive care unit hours, and readmission in 30 days, and mortalities (in-hospital mortality, 30-day mortality, surgical mortality) were compared among various BMI groups after cardiac surgery. Age, sex, surgery type, family history of coronary artery disease, diabetes, hypertension, heart failure, and lipid-lowering medication were the risk factors for early outcomes. Multiple logistic regression analysis indicated that the underweight and class III obese BMI groups demonstrated significant, adverse differences in some short-term outcomes, including deep sternal infection, prolonged ventilation, new atrial fibrillation/flutter, and renal failure. However, being in the overweight or class I obese group demonstrated a positive effect on discharge and surgical mortality.

CONCLUSIONS

The results of this study demonstrated that extreme obesity and underweight were significantly associated with early major adverse clinical outcomes. However, there was an "obese paradox" in short-term mortality after cardiac surgery.

The combined effect of age and body mass index on outcomes in foregut surgery: a regression model analysis of the National Surgical Quality Improvement Program data

BACKGROUND

In a parallel demographic phenomenon, the elderly and obese populations will become a larger part of our population and surgical practices. The elderly obese surgical risk profile is not clearly defined, although studies have confirmed their independent negative effect on surgical outcomes. Benign foregut surgery is a relatively common complex procedure performed on this demographic and warrants deeper investigation into outcomes. We investigate the synergistic effect of age and body mass index (BMI) on the outcomes of benign foregut surgery.

METHODS

Data from National Surgical Quality Improvement Program were collected for all patients undergoing foregut surgery from 2005 to 2012. Subjects were over 18 years of age and 16 BMI. Primary and secondary outcomes were 30-day mortality and overall 30-day morbidity, respectfully. Binary logistic regression models were used to assess independent and interactive effects of age and BMI.

RESULTS

A total of 19,547 patients had an average age and BMI of 57 and 29.7, respectively. Sample 30-day mortality was 0.32 %. Every 10-year age increase led to a 46 % increased odds of mortality. BMI showed a bimodal distribution with underweight and morbidly obese patients having increased mortality. The effect of BMI only became apparent with increasing age.

CONCLUSIONS

Both age and BMI are independent predictors of mortality; only older patients experienced the bimodal BMI effect. Therefore, increasing age and BMI have a synergistic effect on outcomes after foregut operations.

The influence of body mass index on outcomes in patients undergoing cardiac surgery: does the obesity paradox really exist?

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 prospectively 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 Infarction (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 Infarction 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.

The obesity paradox in patients undergoing transcatheter aortic valve implantation

BACKGROUND

Obesity is a major risk factor for cardiovascular morbidity and mortality. A considerable number of studies, however, showed better outcomes for overweight patients undergoing cardiovascular interventions-the so called obesity paradox.

HYPOTHESIS

Increased body mass index (BMI) is independently associated with improved survival following transcatheter aortic valve implantation (TAVI).

METHODS

We analyzed the data of 409 consecutive patients undergoing TAVI in our medical center. Patients were categorized into 4 groups according to BMI: underweight (≤18.4 kg/m(2) ), normal weight (18.5-24.9 kg/m(2) ), overweight (25-29.9 kg/m(2) ), and obese (≥30 kg/m(2) ). Procedure-related complications were recorded, as well as 30-day and 1-year all-cause mortality rates.

RESULTS

Obese patients had a higher prevalence of comorbidities and higher incidence of vascular complications compared with the normal-weight patients (16% vs 7%, P = 0.013). Nevertheless, 30-day mortality was similar among the groups, whereas 1-year mortality was lower among the overweight and obese patients (BMI >25) (P = 0.038). After adjusting for differences in baseline characteristics, increase in BMI was found to be independently associated with improved survival following TAVI (hazard ratio: 0.94, confidence interval: 0.89-0.99, P = 0.043).

CONCLUSIONS

In our single-center study, obesity and overweight were independently associated with better outcome, supporting the obesity paradox in the TAVI population.

Effect of body mass index <20 kg/m(2) on events in patients who underwent transcatheter aortic valve replacement

The Valve Academic Research Consortium-2 has defined body mass index (BMI) <20 as indicative of frailty, which may be one of the co-morbidities not captured by traditional risk factors after transcatheter aortic valve replacement (TAVR). This study aimed to assess the impact of low BMI on clinical outcomes after TAVR. A total of 777 consecutive patients scheduled for TAVR were classified into 3 groups as BMI <20 (n = 56), 20 to 24.9 (n = 322), and ≥25 (n = 399). Procedural complications and clinical outcomes were compared among the 3 groups. They were also analyzed according to propensity-matching model A (BMI <20 [n = 50] vs ≥20 [n = 50]), model B (BMI <20 [n = 50] vs 20 to 24.9 [n = 50]), and model C (BMI <20 [n = 47] vs ≥25 [n = 47]). The differences in baseline characteristics among the 3 groups were adequately adjusted in 3 matched models. Valve Academic Research Consortium-2-defined end points and other complications were similar among the 3 groups in each model. Kaplan-Meier curves indicated no significant differences in cumulative 30-day survival (BMI <20 [91.0%] vs 20 to 24.9 [86.3%], p = 0.33; BMI <20 [91.0%] vs ≥25 [91.4%], p = 0.91, respectively) and 1-year survival (BMI <20 [74.3%] vs 20 to 24.9 [71.8%], p = 0.71; BMI <20 [74.3%] vs ≥25 [77.0%], p = 0.71; respectively). These survival rates were also similar in each of the 3 matched models. In conclusion, BMI <20 was not associated with increased early or midterm mortality. BMI <20 alone may not constitute an additional co-morbidity factor in patients who underwent TAVR.

The obesity paradox: understanding the effect of obesity on mortality among individuals with cardiovascular disease

OBJECTIVE

To discuss possible explanations for the obesity paradox and explore whether the paradox can be attributed to a form of selection bias known as collider stratification bias.

METHOD

The paper is divided into three parts. First, possible explanations for the obesity paradox are reviewed. Second, a simulated example is provided to describe collider stratification bias and how it could generate the obesity paradox. Finally, an example is provided using data from 17,636 participants in the US National and Nutrition Examination Survey (NHANES III). Generalized linear models were fit to assess the effect of obesity on mortality both in the general population and among individuals with diagnosed cardiovascular disease (CVD). Additionally, results from a bias analysis are presented.

RESULTS

In the general population, the adjusted risk ratio relating obesity and all-cause mortality was 1.24 (95% CI 1.11, 1.39). Adjusted risk ratios comparing obese and non-obese among individuals with and without CVD were 0.79 (95% CI 0.68, 0.91) and 1.30 (95% CI=1.12, 1.50), indicating that obesity has a protective association among individuals with CVD.

CONCLUSION

Results demonstrate that collider stratification bias is one plausible explanation for the obesity paradox. After conditioning on CVD status in the design or analysis, obesity can appear protective among individuals with CVD.

Effect of body mass index on 30- and 365-day complication and survival rates of transcatheter aortic valve implantation (from the FRench Aortic National CoreValve and Edwards 2 [FRANCE 2] registry)

The "obesity paradox" that patients with high body mass index (BMI) have good prognoses remains controversial. This study aimed to assess the impact of BMI on clinical outcomes in patients who underwent transcatheter aortic valve implantation (TAVI). Data from the French national TAVI registry were collected for 3,072 patients who underwent TAVI from January 2010 to October 2011. The patients were categorized into 4 groups according to BMI (kg/m(2)): underweight (<18.5 kg/m(2)), normal weight (18.5 to 25 kg/m(2)), overweight (25 to 30 kg/m(2)), and obese (>30 kg/m(2)). Thereafter, clinical outcomes were compared among the 4 groups. The BMI distribution was 3.1% (n = 95), 44.1% (n = 1,355), 34.2% (n = 1,050), and 18.6% (n = 572). Although the 4 groups greatly differed in baseline clinical background, they had similar procedural success rates (95.8%, 97.1%, 97.3%, and 95.6%, p = 0.23). Major vascular complication was significantly associated with the underweight patients after adjusting for the other potential confounders (odds ratio 2.33, 95% confidence interval 1.17 to 4.46, p = 0.016). The cumulative postoperative survival rates were increasing across the 4 groups at 30 days (83.2%, 88.9%, 91.6%, and 93.0%, p = 0.003) and 1 year (67.9%, 73.6%, 77.4%, and 80.3%, p = 0.006). In a multivariate Cox regression analysis, the overweight and obese patients were independently associated with superior cumulative survival rate at 1 year (hazard ratios 0.74 and 0.71, 95% confidence intervals 0.57 to 0.97 and 0.59 to 0.87, p = 0.050 and 0.029, respectively). In conclusion, major morbidity and 1-year mortality were less in overweight and obese patients than those classified as normal weight even in a TAVI cohort.

Effect of body mass index on outcome in patients with suspected coronary artery disease referred for stress echocardiography

In patients with hypertension, heart failure, or coronary artery disease (CAD), obese patients have been shown to have a lower cardiac event rate compared with normal weight counterparts. This phenomenon has been termed the "obesity paradox." We sought to determine whether the obesity paradox exists in a cohort of patients referred for stress echocardiography. We evaluated 4,103 patients with suspected CAD (58 ± 13 years; 42% men) undergoing stress echocardiography (52% exercise and 47% dobutamine). Patients were divided into 3 groups on the basis of body mass index (BMI): 18.5 to 24.9, 25 to 29.9, and >30 kg/m(2). During the follow-up of 8.2 ± 3.6 years, there were 683 deaths (17%). Myocardial ischemia was present in 21% of the population. Myocardial ischemia was more prevalent in patients with a BMI of 18.5 to 24.9 kg/m(2) (26%) than those with a BMI of 25 to 29.9 kg/m(2) (21%) and >30 kg/m(2) (18%). Patients with a BMI of >30 kg/m(2) had the lowest death rate (1.2%/year) compared with those with a BMI of 25 to 29.9 kg/m(2) (1.75%/year) and 18.5 to 24.9 kg/m(2) (2.9%/year; p <0.001). After adjusting for significant clinical variables including exercise capacity, patients with higher BMI (>30 kg/m(2) and 25 to 29.9 kg/m(2)) had less risk of mortality compared with those with a BMI of 18.5 to 24.9 kg/m(2) (hazard ratio 0.58, 95% confidence interval 0.47 to 0.72, p <0.0001 and hazard ratio 0.69, 95% confidence interval 0.57 to 0.82, p <0.0001, respectively). In conclusion, higher survival rate in patients with higher BMI as previously described in patients with hypertension, heart failure, and CAD extends to patients with suspected CAD referred for stress echocardiography, independent of exercise capacity.

Coronary artery calcification is inversely related to body morphology in patients with significant coronary artery disease: a three-dimensional intravascular ultrasound study

AIMS

Emerging data have indicated unexpected complexity in the regulation of vascular and bone calcification. In particular, several recent studies have challenged the concept of a universally positive relationship between body morphology [weight, height, body mass index (BMI), body surface area (BSA)] and the extent of vascular calcification. We sought to clarify these discrepancies and investigated the relationship between index lesion coronary artery calcification (CAC) and body morphology in patients undergoing percutaneous coronary intervention (PCI) using three-dimensional intravascular ultrasound (IVUS).

METHODS AND RESULTS

We analysed CAC in patients who underwent PCI with pre-intervention IVUS imaging. The main outcome measure was the calcium index (CalcIndex); a three-dimensional IVUS-derived measure of total calcification per obstructive coronary lesion. A total of 346 patients (65.3 ± 10.6 years; 29.5% females) underwent PCI with IVUS-based CAC assessment. CalcIndex was categorized as zero-low (0-0.1399; n = 152) or intermediate-high (0.1400-1.2541; n = 194). All measures of body morphology were lower in patients with intermediate-high CalcIndex (height, P = 0.024; weight, P = 0.008; BMI, P = 0.064; BSA, P = 0.005). In adjusted multivariable models, weight and BSA were independent inverse predictors of intermediate-high CalcIndex [weight: odds ratio (OR) 0.986, P = 0.017; BSA: OR 0.323, P = 0.012] while CalcIndex also trended towards an inverse association with both height (P = 0.068) and BMI (P = 0.064). These independent inverse associations were consistent across multiple clinical subgroups, including stratification by age, race, gender, diabetes, and renal impairment.

CONCLUSION

Using three-dimensional IVUS to assess vascular calcification, these data confirm an independent, inverse relationship between body size and index lesion CAC in patients with obstructive coronary artery disease.

Synergistic effect of age and body mass index on mortality and morbidity in general surgery

BACKGROUND

The elderly population (aged 65 y and older) is expected to be the dominant age group in the United States by 2030. In addition, the prevalence of obesity in the United States is growing exponentially. Obese elderly patients are increasingly undergoing elective or emergent general surgery. There are few, if any, studies highlighting the combined effect of age and body mass index (BMI) on surgical outcomes. We hypothesize that increasing age and BMI synergistically impact morbidity and mortality in general surgery.

MATERIALS AND METHODS

We collected individual-level, de-identified patient data from the Michigan Surgical Quality Collaborative. Subjects underwent general surgery with general anesthetic, were >18 y, and had a BMI between 19 and 60. Primary and secondary outcomes were 30-d "Any morbidity" and mortality (from wound, respiratory, genitourinary, central nervous system, and cardiac systems), respectively. Preoperative risk variables included diabetes, dialysis, steroid use, cardiac risk, wound classification, American Society of Anesthesiology class, emergent cases, and 13 other variables. We conducted binary logistic regression models for 30-d morbidity and mortality to determine independent effects of age, BMI, interaction between both age and BMI, and a saturated model for all independent variables.

RESULTS

We identified 149,853 patients. The average age was 54.6 y, and the average BMI was 30.9. Overall 30-d mortality was 2%, and morbidity was 6.7%. Age was a positive predictor for mortality and morbidity, and BMI was negatively associated with mortality and not significantly associated with morbidity. Age combined with higher BMI was positively associated with morbidity and mortality when the higher age groups were analyzed. Saturated models revealed age and American Society of Anesthesiology class as highest predictors of poor outcomes.

CONCLUSIONS

Although BMI itself was not a major independent factor predicting 30-d major morbidity or mortality, the morbidly obese, elderly (>50 and 70 y, respectively) subgroup may have an increased morbidity and mortality after general surgery. This information, along with patient-specific factors and their comorbidities, may allow us to better take care of our patients perioperatively and better inform our patients about their risk of surgical procedures.

Body mass index is inversely associated with mortality in patients with peripheral vascular disease

BACKGROUND

Current guidelines contain no advice on how to manage obesity and underweight in patients with peripheral vascular disease (PVD).

OBJECTIVES

The aim of this study was to assess the association of underweight, overweight and obesity with mortality in patients with PVD.

PATIENTS AND METHODS

We recruited 1472 patients with a broad range of presentations of PVD. Underweight, overweight and obesity were defined by body mass index (BMI) and associated with mortality using Kaplan Meier and Cox proportional hazard analyses.

RESULTS

Survival at 3 years was 37.5, 78.1, 86.8 and 87.0% for patients that were underweight, normal weight, overweight and obese at recruitment, respectively, p<0.001. Patients that were underweight had approximately twice the risk of dying (RR 2.15, 95% CI 1.31-3.55, p=0.003), while patients that were overweight (RR 0.67, 95% CI 0.49-0.91, p=0.011) or obese (RR 0.59, 95% CI 0.41-0.85, p=0.005) had approximately half the risk of dying, after adjustment for other risk factors and using normal weight subjects as the reference group. 823 patients had waist circumference measured at recruitment. Patients with waist circumference in the top quartile had half the risk of dying (RR 0.50, 95% CI 0.26-0.98, p=0.045). In 267 patients we assessed the relationship between BMI and abdominal fat volumes using computed tomography. BMI was highly correlated with both intra-abdominal and subcutaneous fat volumes.

CONCLUSIONS

Obesity whether assessed by BMI or central fat deposition is associated with reduced risk of dying in patients with established PVD. Underweight is highly predictive of early mortality in patients with PVD.