Association of body mass index with major cardiovascular events and with mortality after percutaneous coronary intervention

The effect of body mass index on stroke prognosis: A systematic review and meta-analysis of 32 cohort studies with 330,353 patients

BACKGROUND

Many studies have explored the impact of body mass index (BMI) on stroke prognosis, yet findings remain inconsistent.

AIMS

The aims of this study were to conduct a systematic review and meta-analyses to summarize the existing evidence on BMI and stroke outcomes.

METHODS

PubMed, Web of Science, Embase, The Cochrane Library, CNKI, CBM, Wanfang Database, and VIP Database were systematically searched from inception to 1 January 2023. Cohort studies were included if they reported on a population of patients with stroke, evaluated BMI on stroke outcomes (mortality/recurrence/score of modified Rankin scale (mRs)), and reported original data. Data extraction and quality assessment were independently undertaken by two reviewers. Stata 16.0 software was used for meta-analysis.

RESULTS

Thirty-two studies involving 330,353 patients (5 Chinese language articles) were included in the analysis. The proportion of underweight, overweight, and obese patients was 1.85%, 18.2%, and 15.6%, respectively. Compared with normal weight, being underweight was associated with an increased risk of mortality (relative risk (RR) = 1.78, 95% confidence interval (CI) = 1.60-1.96), poor functional outcomes defined as modified Rankin scale ⩾ 3 (RR = 1.33, 95% CI = 1.22-1.45), and stroke recurrence (RR = 1.19, 95% CI = 1.04-1.37). Being overweight but not obese was associated with reduced mortality (RR = 0.81, 95% CI = 0.74-0.89) and better functional outcomes (RR = 0.92, 95% CI = 0.89-0.96), but did not alter the risk of stroke recurrence (RR = 1.03, 95% CI = 0.90-1.17). Obesity was associated with lower risk of mortality (RR = 0.76, 95% CI = 0.72-0.81) and better functional outcomes (RR = 0.89, 95% CI = 0.84-0.94).

CONCLUSIONS

Our findings indicate that in patients with stroke, being underweight is associated with an increased risk of mortality, poor functional outcomes, and stroke recurrence. In contrast, being overweight but not obese, or being obese, was associated with a decreased risk of mortality and better functional outcomes. This is consistent with the obesity paradox in stroke, whereby obesity increases stroke risk in the general population but is associated with improved outcome in patients suffering stroke.

Association of Age- and Body Mass Index-Stratified High On-Treatment Platelet Reactivity With Coronary Intervention Outcomes in East Asian Patients

BACKGROUND

Although age and body mass index (BMI) significantly affect platelet reactivity units and clinical outcomes after percutaneous coronary intervention, there are limited data on the relationship between high on-treatment platelet reactivity (HPR) and clinical outcomes on age and BMI differences. Thus, we investigated the association of HPR with clinical outcomes according to age and BMI.

METHODS AND RESULTS

The study analyzed 11 714 patients who underwent platelet function tests after percutaneous coronary intervention. The primary end point was the occurrence of major adverse cardiac and cerebrovascular events (MACCEs), whereas the secondary end point was major bleeding. HPR was defined as platelet reactivity units ≥252. Patients were categorized by age (<67 years of age or ≥67 years of age) and BMI (≤22.6 kg/m2 or >22.6 kg/m2). Patients <67 years of age with HPR had increases in both MACCEs (adjusted hazard ratio [HR], 1.436 [95% CI, 1.106-1.867]; P=0.007) and major bleeding (adjusted HR, 1.584 [95% CI, 1.095-2.290]; P=0.015) compared with the those with non-HPR, respectively. In patients ≥67 years of age with HPR, there were no differences in MACCEs, but there was a decrease in major bleeding (adjusted HR, 0.721 [95% CI, 0.542-0.959]; P=0.024). Meanwhile, patients with HPR with BMI >22.6 kg/m2 had increases in MACCEs (adjusted HR, 1.387 [95% CI, 1.140-1.688]; P=0.001). No differences were shown in major bleeding.

CONCLUSIONS

HPR was linked to an increase in MACCEs or a decrease in major bleeding in patients after percutaneous coronary intervention, depending on age and BMI. This study is the first to observe that clinical outcomes in patients with HPR after percutaneous coronary intervention may vary based on age and BMI. Because the study is observational, the results should be viewed as hypothesis generating and emphasize the need for randomized clinical trials.

Influence of Obesity on Coronary Artery Disease and Clinical Outcomes in the ADVANCE Registry

BACKGROUND

The relationship between body size and cardiovascular events is complex. This study utilized the ADVANCE (Assessing Diagnostic Value of Noninvasive FFR_CT in Coronary Care) Registry to investigate the association between body mass index (BMI), coronary artery disease (CAD), and clinical outcomes.

METHODS

The ADVANCE registry enrolled patients undergoing evaluation for clinically suspected CAD who had >30% stenosis on cardiac computed tomography angiography. Patients were stratified by BMI: normal <25 kg/m², overweight 25-29.9 kg/m², and obese ≥30 kg/m². Baseline characteristics, cardiac computed tomography angiography and computed tomography fractional flow reserve (FFR_CT), were compared across BMI groups. Adjusted Cox proportional hazards models assessed the association between BMI and outcomes.

RESULTS

Among 5014 patients, 2166 (43.2%) had a normal BMI, 1883 (37.6%) were overweight, and 965 (19.2%) were obese. Patients with obesity were younger and more likely to have comorbidities, including diabetes and hypertension (all P<0.001), but were less likely to have obstructive coronary stenosis (65.2% obese, 72.2% overweight, and 73.2% normal BMI; P<0.001). However, the rate of hemodynamic significance, as indicated by a positive FFR_CT, was similar across BMI categories (63.4% obese, 66.1% overweight, and 67.8% normal BMI; P=0.07). Additionally, patients with obesity had a lower coronary volume-to-myocardial mass ratio compared with patients who were overweight or had normal BMI (obese BMI, 23.7; overweight BMI, 24.8; and normal BMI, 26.3; P<0.001). After adjustment, the risk of major adverse cardiovascular events was similar regardless of BMI (all P>0.05).

CONCLUSIONS

Patients with obesity in the ADVANCE registry were less likely to have anatomically obstructive CAD by cardiac computed tomography angiography but had a similar degree of physiologically significant CAD by FFR_CT and similar rates of adverse events. An exclusively anatomic assessment of CAD in patients with obesity may underestimate the burden of physiologically significant disease that is potentially due to a significantly lower volume-to-myocardial mass ratio.

Τhe Burden of Obesity on Adult Survivors of Congenital Heart Disease, Past, and Future Directions

The ongoing obesity epidemic has started to ebb. However, as most children with congenital heart disease survive until adulthood, the burgeoning trend has started to spill over in the adult congenital heart disease population as well. This review aims to decipher the prevalence, outcomes, and future directions of obesity in adult survivors of congenital heart disease.

Secular trends of the prevalence of emaciation, overweight, and obesity among school-aged children in Yunnan province, 1985–2019: A serial cross-sectional surveillance study in China

Objective

To understand the trends of nutrition in children and adolescents, which may further help to prevent and control chronic diseases in younger ages.

Methods

The Chinese National Surveys on Students' Constitution and Health (CNSSCH) in Yunnan is a survey of growth conditions, physical fitness, and health status of students in Yunnan and uses a series of complex multistage stratified sampling of seven prefectures consisting of 16 counties. Sampling schools were held constant over 35 years. The participants were randomly selected among 7–18 aged students. We used data from 1985, 1991, 2000, 2005, 2010, 2014, and 2019 CNSSCH of Yunnan. According to body mass index (BMI) criteria of National Working Group for Obesity in China (WGOC-BMI criteria), a participant's nutrition (emaciation, overweight or obesity) was defined. This study is based on survey data from 129,520 participants in 1985 (n = 14,683), 1991 (n = 4,894), 1995 (n = 6,673), 2000 (n = 9,751), 2005 (n = 23,461), 2010 (n = 22,889), 2014 (n = 23,003) and 2019 (24,166).

Results

Since 1985, the trends of emaciation over 35 years were decreasing. Regardless of gender, area, and age, the prevalence of obesity and overweight were increased. The average annual growth rate of overweight and obesity was quicker in rural areas and boys than in urban areas and girls. In Yunnan, emaciation, overweight, and obesity disparity in children were common phenomena, with differences in areas and gender.

Conclusion

Children in Yunnan faced the triple burden of malnutrition (emaciation, overweight, and obesity). We should take comprehensive policies and effective intervention measures to decrease the rate of nutrition deficiencies in school-aged children.

Safety and efficacy of direct oral anticoagulants in comparison with warfarin across different BMI ranges: A systematic review and meta-analysis

Background

Many publications have compared various outcomes defining safety and efficacy of DOACs across different BMI ranges. Our meta-analysis compares warfarin and DOACs for its treatment effects over different BMI ranges.

Methods

A systematic search was conducted from inception to May 2021 on PubMed, Scopus and Embase databases. The data was extracted and pooled using a random effects model. Our study consisted of patients being treated for VTE and AF, across different BMI categories. For the comparison of DOAC, risk ratios (RR) with 95% confidence intervals (CIs) were used, whilst for the second comparison between warfarin and DOACs odds ratios (OR) were used.

Results

In our first comparison, 12 studies (n = 254,908 patients) were included. For our second comparison, six studies (n = 109,609 patients) were included. Major bleeding events in the underweight group were higher than normal weight [RR: 1.89 (1.10, 3.23); P = 0.02; I² = 0%]. Overweight patients were related with reduced rates of VTE than in patients with normal BMI [RR: 0.86 (0.76, 0.97); P = 0.02; I² = 0%]. In comparison with patients receiving warfarin, DOACs had significantly reduced risk of major bleeding in normal weight, overweight and obese [OR: 0.64 (0.49, 0.83); P = 0.0007 I² = 90%].

Conclusion

The risk of VTE reduces with an increasing BMI, hence there could be a possible obesity paradox in patients with anticoagulation therapy. In comparison to warfarin, DOACs proved to be the safer option by having a reduced risk of bleeding across all BMI categories.

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Warfarin therapy and its effectiveness for prevention of thromboembolism.

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Effect of warfarin and DOACs over different BMI ranges.

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Safety and efficacy of DOACs across different BMI ranges.

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Lower risk of bleeding in normal weight, overweight, and obese patients with DOACs.

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Warfarin and DOACs across different BMI categories in VTE and AF patients.

Influence of changes in body fat on clinical outcomes in a general population: a 12-year follow-up report on the Ansan-Ansung cohort in the Korean Genome Environment Study

BACKGROUND

The impact of the changes in the obesity status on mortality has not been established; thus, we investigated the long-term influence of body fat (BF) changes on all-cause deaths and cardiovascular outcomes in a general population.

METHODS

A total of 8374 participants were observed for 12 years. BF was measured at least two times using a bioimpedance method. The causes of death were acquired from the nationwide database. A major adverse cardiovascular event (MACE) was defined as a composite of myocardial infarction, coronary artery disease, stroke, and cardiovascular death. Standard deviations (SDs) were derived using a local regression model corresponding to the time elapsed between the initial and final BF measurements (SD_T) and were used to standardize the changes in BF (ΔBF/SD_T).

RESULTS

The incidence rates of all-cause death, cardiovascular death, and MACE were the highest in the participants with ΔBF/SD_T <-1 and lowest in the participants with ΔBF/SD_T ≥1. Multivariate Cox proportional hazard models adjusted for relevant covariates, including baseline obesity and physical activity, showed that the risks of all-cause deaths (hazard ratio [HR] 0.58; 95% confidence intervals [CI] 0.53-0.64), cardiovascular deaths (HR 0.63; 95% CI 0.51-0.78) and MACEs (HR 0.68; 95% CI 0.62-0.75) decreased as ΔBF/SD_T increased. Subgroup analyses showed that existing cardiovascular diseases weakened the associations between higher ΔBF/SD_T and better outcomes, while high physical activity and exercise did not impact the associations.

CONCLUSION

Increasing BF was associated with a lower risk of all-cause death, cardiovascular death, and MACE in the general population.Key messagesIncreasing body fat is associated with a lower risk of all-cause death, cardiovascular death, and major cardiovascular adverse events in a low-risk ageing general population, independently of physical activity, underlying cardiovascular disease burden, changes in muscle mass, and baseline obesity status.Fatness measured at baseline requires adjustment for the changes in fatness during the follow-up to reveal its impact on the clinical outcomes.

Impact of Low Body Mass Index on Features of Coronary Culprit Plaques and Outcomes in Patients With Acute Coronary Syndrome

The mechanisms behind poorer cardiac outcomes in underweight patients with acute coronary syndrome (ACS) are not understood and features of coronary culprit lesions in underweight ACS patients have not been fully examined. A total of 1,683 patients with ACS were divided into 4 groups according to body mass index (BMI): <18.5 (n = 73), 18.5 to 24.9 (n = 995), 25 to 29.9 (n = 488), and ≥30 (n = 117). Angiography and optical coherence tomography (OCT) images were analyzed for 1,428 of these patients who had primary percutaneous coronary intervention (PCI) and 838 who had primary PCI with OCT guidance, respectively. Diabetes (p <0.001), hypertension (p <0.001), and dyslipidemia (p <0.001) were less prevalent in BMI <18.5. Statin prescription at discharge was less frequent in the BMI <18.5 group (p <0.001). Quantitative coronary angiography analyses revealed smaller reference vessel (p = 0.001) and minimum lumen diameters after PCI (p = 0.019) and OCT revealed longer lipidic plaque length (p = 0.029) in the BMI <18.5 group. Kaplan-Meier analyses revealed higher rates of cardiac mortality (p <0.001) and major bleeding (p = 0.034) during the 2-year follow-up in the BMI <18.5 group. After adjusting for traditional cardiovascular risk factors, BMI <18.5 independently predicted 2-year cardiac mortality (hazard ratio 1.917 [95% confidence interval [1.082 to 3.397], p = 0.026). In conclusion, being underweight contributed to poorer cardiac outcomes in established ACS population. Smaller minimum lumen diameter after PCI and further progressed atherosclerosis at the culprit lesions despite their lower prevalence of comorbid metabolic risk factors may be related partly to poorer cardiac outcomes.

Obesity May Not Be a Risk of Non-Target Lesion Revascularization in the Elderly Patients

Obesity is assumed to be one of the robust risk factors for coronary artery disease. However, the effects of obesity on the progression of atherosclerosis in patients in different age groups after percutaneous coronary intervention (PCI) remain unclear. This study aimed to examine the effect of obesity on prognosis in different age groups.Consecutive patients who underwent urgent or elective PCI were surveyed for this study and were then divided into the elderly group and middle-aged group with a cut-off age of 70 years. All patients underwent coronary angiography or coronary computed tomography angiography 1 year after PCI to examine the progression of atherosclerosis. The primary endpoint was revascularization for a new lesion within 2 years after PCI. In addition, the main effects and correlations between obesity and age were examined. Multivariate logistic regression analysis was conducted to identify independent predictors of non-target lesion revascularization (non-TLR).Of the 711 patients who met the criteria and were available for follow-up analysis, the incidence of non-TLR within 2 years was 97/711 (13.6%). The higher incidence of non-TLR in patients with obesity was observed only in the middle-aged group. Furthermore, in the multivariate analysis, obesity was independently associated with non-TLR only in the middle-aged group.The findings of the present study would enable us to construct the hypothesis that obesity in elderly patients may not be an independent predictor of the incidence of non-TLR, indicating that the management to prevent non-TLR may vary depending on the age of the patient.

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

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

Baseline, procedural and outcome features of patients undergoing transcatheter aortic valve implantation according to different body mass index categories

BACKGROUND

Transcatheter aortic valve implantation (TAVI) has become first-line treatment for severe aortic valve stenosis in patients with moderate, high or prohibitive surgical risk. However, access site complications may occur more frequently in extreme body mass index (BMI) categories. The aim of this study was to describe the features and outcomes of patients undergoing TAVI in a comprehensive Italian prospective clinical registry, focusing on BMI classes.

METHODS

A national prospective database was queried for baseline, procedural, and outcome details of patients undergoing TAVI according to established BMI categories: underweight (BMI <18.5 kg/m²), normal weight (BMI 18.5-24.9 kg/m²), overweight (BMI 25.0-29.9 kg/m²), and obese (BMI≥30 kg/m²). Short- and long-term outcomes, including major adverse events (MAE), i.e. the composite of death, stroke, myocardial infarction, major vascular complication, major bleeding, or renal failure, were appraised with bivariate and multivariable analyses.

RESULTS

A total of 3075 subjects were included, 64 (2.1%) were underweight, 1319 (42.9%) were normal weight, 1152 (37.4%) were overweight, and 540 (17.6%) were obese. Several baseline differences were evident, including gender, diabetes mellitus, renal function, chronic obstructive pulmonary disease, surgical scores, and left ventricular ejection fraction (LVEF) (all P<0.05). Several procedural differences were also evident, including percutaneous approach, predilation, prosthesis type and size (all P<0.05), with postprocedural aortic regurgitation >2+ significantly more common in underweight patients (P<0.05). Nonetheless, unadjusted analysis for one-month outcomes showed similar rates for fatal and non-fatal outcomes, including MAE (all P>0.05), with the notable exception of permanent pacemaker implantation, which was more common in higher BMI classes (P=0.010) Unadjusted analysis for long-term events showed an increased rate of death in underweight patients (P=0.024). Multivariable adjusted analysis confirmed the increased risk of permanent pacemaker implantation in obese patients (P=0.015 when comparing obese vs. normal weight subjects), but disproved differences in long-term mortality and other outcomes (P>0.05 for all comparisons).

CONCLUSIONS

Irrespective of BMI class, TAVI is associated with favorable outcomes in surgical high-risk risk patients, with the notable exclusion of permanent pacemaker implantation, which is significantly more common in obese subjects.

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

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

Relation of Body Mass Index to Outcomes in Acute Coronary Syndrome

We assessed the association of BMI with all-cause and cardiovascular (CV) mortality in a contemporary acute coronary syndrome cohort. Patients from the Australian Cooperative National Registry of Acute Coronary Care, Guideline Adherence and Clinical Events and Global Registry of Acute Coronary Events between 2009 and 2019, were divided into BMI subgroups (underweight: <18.5, healthy: 18.5 to 24.9, overweight: 25 to 29.9, obese: 30 to 39.9, extremely obese: >40). Logistic regression was used to determine the association between BMI group and outcomes of all cause and CV death in hospital, and at 6 months. 8,503 patients were identified, mean age 64 ± 13, 72% male. The BMI breakdown was: underweight- 95, healthy- 2,140, overweight- 3,258, obese- 2,653, extremely obese- 357. Obese patients were younger (66 ± 12 vs 67 ± 13), with more hypertension, diabetes, and dyslipidemia vs healthy (all p < 0.05). Obese had lower hospital mortality than healthy: all-cause: 1% versus 4%, aOR (95% CI): 0.49(0.27, 0.87); CV: 1% versus 3%, 0.51(0.27, 0.96). At 6-month underweight had higher mortality than healthy: all-cause: 11% versus 4%, 2.69(1.26, 5.76); CV: 7% versus 1%, 3.54(1.19, 10.54); whereas obese had lower mortality: all-cause: 1% versus 4%, 0.48(0.29, 0.77); CV: 0.4% versus 1%, 0.42(0.19, 0.93). When BMI was plotted as a continuous variable against outcome a U-shaped relationship was demonstrated, with highest event rates in the most obese (>60). In conclusion, BMI is associated with mortality following an acute coronary syndrome. Obese patients had the best outcomes, suggesting persistence of the obesity paradox. However, there was a threshold effect, and favorable outcomes did not extend to the most obese.

Obesity and Coronary Heart Disease: Epidemiology, Pathology, and Coronary Artery Imaging

Overweight and obesity contribute to the development of cardiovascular disease (CVD) in general and coronary heart disease (CHD) in particular in part by their association with traditional and nontraditional CVD risk factors. Obesity is also considered to be an independent risk factor for CVD. The metabolic syndrome, of which central obesity is an important component, is strongly associated with CVD including CHD. There is abundant epidemiologic evidence of an association between both overweight and obesity and CHD. Evidence from postmortem studies and studies involving coronary artery imaging is less persuasive. Recent studies suggest the presence of an obesity paradox with respect to mortality in persons with established CHD. Physical activity and preserved cardiorespiratory fitness attenuate the adverse effects of obesity on CVD events. Information concerning the effect of intentional weight loss on CVD outcomes in overweight and obese persons is limited.

Relation of Body Mass Index to Risk of Death or Stroke in Patients Who Underwent Transcatheter Aortic Valve Implantation

Obesity and overweight have been associated with better clinical outcomes in different populations with a diverse spectrum of cardiovascular disease (obesity paradox). However, conflicting data exist about the relation between body mass index (BMI) and outcomes after transcatheter aortic valve implantation (TAVI). The aim of this study is to evaluate the association of body mass index with clinical outcomes in patients with severe aortic stenosis (AS) who underwent TAVI. The study cohort included 379 consecutive patients with symptomatic severe AS who underwent TAVI between March 2010 and February 2017 in 3 centers in East Asia. Patients were grouped into tertiles of baseline BMI (first tertile: ≤22.3 kg/m², second tertile: 22.4 to 24.8 kg/m², and third tertile: ≥24.9 kg/m²). The primary outcome was a composite of death from any causes or stroke at 1 year. The median (interquartile range) BMI was 23.5 (21.8 to 26.1) kg/m². During the median follow-up of 18.4 months, there were 69 deaths and 23 strokes. At 1 year, the primary outcome occurred in 21.9% in the first tertile, 18.7% in the second tertile, and 7.8% in the third tertile, respectively (p = 0.009). After adjustment for confounding variables, an inverse relation was observed between BMI and primary outcome: with the third BMI tertile as the reference category, the adjusted hazard ratios were 2.51 (95% confidence interval, 1.20 to 5.26) for the second BMI tertile and 2.61 (95% confidence interval, 1.20 to 5.66) for the first BMI tertile. In conclusion, in patients with severe AS who underwent TAVI, an inverse association between BMI and the risk of death or stroke was observed.

Relationship of body mass index and waist circumference with clinical outcomes following percutaneous coronary intervention

BACKGROUND

A biphasic, U-shape relationship has been reported between body mass index (BMI) and clinical outcomes following percutaneous coronary intervention (PCI). However, the relationship between waist circumference (WC) and the cardiovascular risk following PCI has not been reported.

METHODS

A prospective cohort study was performed. A major adverse cardiac event (MACE) was defined as a composite of cardiac death (CD), nonfatal myocardial infarction (NFMI) and target vessel revascularization (TVR). Patients were evenly divided into 4 groups according to BMI (Q1BMI, Q2BMI, Q3BMI and Q4BMI) and WC (Q1WC, Q2WC, Q3WC and Q4WC).

RESULTS

A total of 1,421 patients were observed for 5 years. The risk of the composite events of CD and NFMI (CD/NFMI) was lower in the Q3WC and Q4WC groups than in the Q1WC group, whereas it was only marginally lower in the Q2BMI group than in the Q1BMI group (ANOVA, p = 0.062). The risk of MACE was highest in the Q1WC group and lowest in the Q3WC group; however, the risk of MACE did not differ among the 4 groups, according to BMI. Multivariate Cox-regression analyses showed that the risk of CD/NFMI gradually decreased with BMI (linear p = 0.030) and with WC (linear p = 0.015). The risks of TVR and MACEs that were driven by TVRs showed a distinguishing biphasic, U-shaped relationship with WC (nonlinear p = 0.009) but not with BMI (nonlinear p = 0.439). Landmark survival analysis showed that the incidences of CD and NFMI were higher in the lower BMI groups and lower WC groups than in the higher BMI groups and higher WC groups, respectively, until 1 year and did not differ afterward. In contrast, the incidence of MACE was highest in Q1WC and lowest in Q3WC (log-rank p = 0.003), whereas the incidence was not different among the groups according to BMI.

CONCLUSIONS

Both BMI and WC were associated with a lower risk of early episodes of CD and NFMI after PCI. In the late period after PCI, WC demonstrated a biphasic, U-shaped association between cardiovascular outcomes and adiposity, whereas BMI did not.

Perceptions and Practices Related to Obesity in Adolescent Students and Their Programmatic Implications: Qualitative Evidence from Ho Chi Minh City, Vietnam

Background Prevalence of obesity in children in Ho Chi Minh City is rising in the last 10 years. We conducted a formative study to explore the perceptions and practices related to obesity, diet and physical activity among the students in two junior high schools in two suburbs in Ho Chi Minh City to aid in the design of an intervention in preventing obesity among adolescent school children. Method We conducted in-depth interviews with twenty participants including students, their parents, physical education teachers and a representative of the Department of Education. Manually coded and organized data were analysed applying a thematic analysis approach to divulge trends, diversities and similarities among the emerging themes. Results The study revealed diversified perceptions of obesity, diet and physical activity and their relationship with adolescent obesity. The findings indicated low practice of physical activity among almost all students who participated in the study. The major barriers to obesity prevention included knowledge gaps, food environment in the school, devaluation of physical activity and academic burden. Conclusion The findings provide contextual insights to design a culturally appropriate and feasible intervention to tackle child and adolescent obesity by harnessing the perspectives of the target populations.

Effects of Body Mass Index on Clinical Outcomes in Female Patients Undergoing Percutaneous Coronary Intervention With Drug-Eluting Stents: Results From a Patient-Level Pooled Analysis of Randomized Controlled Trials

OBJECTIVES

This study sought to investigate the effect of different body mass index (BMI) categories on clinical outcomes in female patients treated with percutaneous coronary intervention (PCI) and drug-eluting stents.

BACKGROUND

Patients with higher BMI might, paradoxically, have better long-term clinical outcomes after acute coronary syndrome treated with PCI.

METHODS

We pooled patient-level data for female participants from 26 randomized trials on PCI with drug-eluting stents. Patients were stratified into underweight (BMI, <18.5), normoweight (BMI, 18.5 to 24.9), overweight (BMI, 25 to 29.9), obese (BMI, 30 to 34.9), or morbidly obese (BMI, ≥35). The primary endpoint was major adverse cardiac events, a composite of death, myocardial infarction, or target lesion revascularization at 3 years.

RESULTS

Among 11,557 female patients included in the pooled database, 9,420 were treated with a drug-eluting stent and had BMI data available. Patients with higher BMI were significantly younger and with more cardiovascular risk factors. Only 139 patients were underweight and had significantly higher adjusted rates of cardiac mortality and all-cause mortality than the rest of the population (hazard ratio: 2.20 [1.31 to 3.71] compared with normoweight). There was a significantly lower frequency of unadjusted 3-year all-cause mortality in overweight, obese, and severely obese patients compared with normoweight. However, following multivariable analysis, a trend toward increased risk of death in severely obese patients was observed, describing an inverse "J"-shaped relation between BMI and 3-year mortality. Conversely, the relationship between BMI and other outcomes, such as major adverse cardiac events, was flat for normoweight and higher BMI.

CONCLUSIONS

The risk of 3-year adjusted cardiac events did not differ across BMI groups, whereas the risk of all-cause mortality compared with normoweight was significantly higher in underweight patients and lower in overweight patients with a trend toward increased risk in the severely obese population.

Risk factors for stent graft thrombosis after transjugular intrahepatic portosystemic shunt creation

Background

To identify risk factors of stent graft thrombosis after transjugular intrahepatic portosystemic shunt (TIPS) creation.

Methods

Patients who underwent TIPS creation between June 2003 and January 2016 and with follow-up assessing stent graft patency were included (n=174). Baseline comorbidities, liver function, procedural details and follow-up liver function tests were analyzed in association with hazards of thrombosis on follow-up. Competing risk cox regression models were used considering liver transplant after TIPS creation as the competing risk variable.

Results

One-, 2- and 5-year primary patency rates were 94.1%, 91.7% and 78.2%, respectively. Patient age [sub-hazard ratio (sHR): 1.13; P=0.001], body mass index (BMI) <30 (sHR: 33.08; P=0.008) and a higher post-TIPS portosystemic pressure gradient (sHR: 1.14; P=0.023) were significantly associated with TIPS thrombosis in multivariate analysis. A higher rate of TIPS thrombosis was observed in those for whom the procedure was clinically unsuccessful (P=0.014). A significant increase in incidence of thrombosis was noted with increasing tertiles of post-TIPS portosystemic gradients (P value for trend=0.017).

Conclusions

Older age, lower BMI and higher post-TIPS portosystemic gradients were associated with higher hazards of shunt thrombosis after TIPS creation using stent grafts. Higher rates of shunt thrombosis were seen in patients for whom TIPS creation was clinically unsuccessful. The association between TIPS thrombosis and higher post-TIPS portosystemic gradients may indicate impaired flow through the shunt, a finding which may be technical or anatomic in nature and should be assessed before procedure completion.

Assessment of the Relationship between Body Mass Index and Incidence of Venous Thromboembolism in Hospitalized Overweight and Obese Patients

STUDY OBJECTIVE

To assess whether a positive linear association exists between body mass index (BMI) and incidence of venous thromboembolism (VTE) in overweight and obese hospitalized patients.

DESIGN

Single-center retrospective observational cohort study.

SETTING

Large academic tertiary care medical center.

PATIENTS

A total of 1452 adults hospitalized between January 1, 2013, and December 31, 2014, who weighed more than 100 kg and had a BMI of 25 kg/m² or greater on admission, and received heparin subcutaneously for VTE prophylaxis. Patients were categorized into four subgroups based on World Health Organization BMI classification: overweight (141 patients), obese class I (305 patients), obese class II (324 patients), and obese class III (682 patients).

MEASUREMENTS AND MAIN RESULTS

The primary outcome was occurrence of VTE in each subgroup; all-cause mortality and length of hospital stay were secondary outcomes. A linear trend test did not show an association between occurrence of VTE and BMI of 25 kg/m² or greater. VTE occurred in 7 (5%) of 141 patients in the overweight group, 5 (2%) of 305 in the obese class I group, 8 (3%) of 324 in the class II group, and 18 (3%) of 682 in the class III group (p=0.573). In addition, no linear association was noted between all-cause mortality or length of hospital stay and BMI of 25 kg/m² or greater. Overall mortality was 10% (146/1452 patients). Ten deaths (7%) occurred in the overweight group, 45 (15%) in the obese class I group, 38 (12%) in the obese class II group, and 53 (8%) in the obese class III group (p=0.067). The median length of hospital stay was 5 days (interquartile range 3-9, p=0.122) for all patients.

CONCLUSION

In overweight and obese hospitalized patients who weighed more than 100 kg and had a BMI of 25 kg/m² or greater, the incidence of VTE did not increase incrementally with increasing severity of obesity.

Polymorphisms of extrinsic death receptor apoptotic genes (FAS -670 G>A, FASL -844 T>C) in coronary artery disease

Apoptosis plays an important role in atherogenesis and rupture of vulnerable plaques in coronary artery disease. FAS and FAS ligand (FASL) induce apoptosis when FAS binds to FAS-L. However sFas blocks apoptosis by binding to FAS and FASL or sFasL. The present study is sought to examine the role of extrinsic apoptotic genes (FAS, FASL) polymorphism and serum levels of FAS, FASL in the pathogenesis and susceptibility to CAD in south Indian population. The study included 300 CAD patients and 300 healthy controls. Lipid profiles, sFas, sFasL were estimated by commercially available kits. FAS -670 G>A, FASL -844 T>C genotypes were analyzed by PCR-RFLP. Secondary structures of pre mRNA were analyzed by the Vienna RNA webserver and gene-gene and gene-environment interactions were determined by MDR analysis. Total cholesterol, triglyceride and LDL levels were significantly high in CAD patients compared to the controls. Molecular analysis revealed that the frequency of the AA genotype of FAS (54% vs 27%) and CC genotypes of FASL (10.3% vs 1.3%) were high in CAD patients compared to controls. Secondary structure analysis of FAS and FASL confirmed our molecular analysis. sFas levels were low while serum sFasL were high in CAD patients. MDR analysis revealed synergistic effects of gene polymorphisms and additive effects of epidemiological factors on risk of CAD. Polymorphisms of FAS (-670 G/A), FASL (-844 T/C) and their circulating levels play an important role in the pathology of CAD.

Low Body Mass Index, Serum Creatinine, and Cause of Death in Patients Undergoing Percutaneous Coronary Intervention

BACKGROUND

Low body mass index (BMI) and serum creatinine are surrogate markers of frailty and sarcopenia. Their relationship with cause-specific mortality in elderly patients undergoing percutaneous coronary intervention is not well studied.

METHODS AND RESULTS

We determined long-term cardiovascular and noncardiovascular mortality in 9394 consecutive patients aged ≥65 years who underwent percutaneous coronary intervention from 2000 to 2011. BMI and serum creatinine were divided into 4 categories. During a median follow-up of 4.2 years (interquartile range 1.8-7.3 years), 3243 patients (33.4%) died. In the multivariable model, compared with patients with normal BMI, patients with low BMI had significantly increased all-cause mortality (hazard ratio [HR] 1.4, 95% CI 1.1-1.7), which was related to both cardiovascular causes (HR 1.4, 95% CI 1.0-1.8) and noncardiovascular causes (HR 1.4, 95% CI 1.06-1.9). Compared with normal BMI, significant reduction was noted in patients who were overweight and obese in terms of cardiovascular mortality (overweight: HR 0.77, 95% CI 0.67-0.88; obese: HR 0.80, 95% CI 0.70-0.93) and noncardiovascular mortality (overweight: HR 0.85, 95% CI 0.74-0.97; obese: HR 0.82, 95% CI 0.72-0.95). In a multivariable model, in patients with normal BMI, low creatinine (≤0.70 mg/dL) was significantly associated with increased all-cause mortality (HR 1.8, 95% CI 1.3-2.5) and cardiovascular mortality (HR 2.3, 95% CI 1.4-3.8) compared with patients with normal creatinine (0.71-1.0 mg/dL); however, this was not observed in other BMI categories.

CONCLUSIONS

We identified a new subgroup of patients with low serum creatinine and normal BMI that was associated with increased all-cause mortality and cardiovascular mortality in elderly patients undergoing percutaneous coronary intervention. Low BMI was associated with increased cardiovascular and noncardiovascular mortality. Nutritional support, resistance training, and weight-gain strategies may have potential roles for these patients undergoing percutaneous coronary intervention.

Relation of Body Mass Index With Adverse Outcomes Among Patients With Atrial Fibrillation: A Meta-Analysis and Systematic Review

BACKGROUND

Several studies have investigated the impact of body mass index (BMI) on the prognosis of atrial fibrillation, but the results remain controversial. We sought to estimate the association of BMI with atrial fibrillation-related outcomes.

METHODS AND RESULTS

We systematically searched the Cochrane Library, PubMed, and Elsevier databases for all studies reporting associations between BMI and atrial fibrillation-related outcomes. Relative risks (RRs) and 95% CIs were extracted and pooled. Nine studies with 49 364 participants were included. Underweight BMI was associated with an increased risk of stroke or systemic embolism (RR 1.67, 95% CI 1.12-2.49), all-cause mortaliity (RR 2.61, 95% CI 2.21-3.09), and cardiovascular death (RR 2.49, 95% CI 1.38-4.50). Nevertheless, the pooled RRs of overweight and obese patients were lower than those of normal-weight patients for stroke or systemic embolism (overweight: RR 0.91, 95% CI 0.80-1.04; obese: RR 0.84, 95% CI 0.72-0.98; grade 1 obesity: RR 0.89, 95% CI 0.71-1.11; grade 2 obesity: RR 0.64, 95% CI 0.45-0.91; grade 3 obesity: RR 0.82, 95% CI 0.54-1.25), all-cause death (overweight: RR 0.78, 95% CI 0.62-0.96; obese: RR 0.84, 95% CI 0.64-1.10; grade 1 obesity: RR 0.64, 95% CI 0.57-0.73; grade 2 obesity: RR 0.70, 95% CI 0.47-1.03; grade 3 obesity: RR 0.72, 95% CI 0.59-0.88), and cardiovascular death (overweight: RR 0.79, 95% CI 0.58-1.08; obese: RR 0.99, 95% CI 0.79-1.24).

CONCLUSIONS

Underweight BMI is associated with an increased risk of stroke or systemic embolism, cardiovascular death, and all-cause death in Asian patients with atrial fibrillation, whereas in all atrial fibrillation patients, overweight and obese BMI was not associated with increased risks of these outcomes.

Impact of Modifiable Cardiovascular Risk Factors on Mortality After Percutaneous Coronary Intervention: A Systematic Review and Meta-Analysis of 100 Studies

Modifiable cardiovascular risk factors such as obesity, hypertension, dyslipidemia, smoking, diabetes mellitus, and metabolic syndrome can easily give rise to coronary heart disease (CHD). However, due to the existence of the so-called "obesity paradox" and "smoking paradox," the impact of these modifiable cardiovascular risk factors on mortality after percutaneous coronary intervention (PCI) is still not clear. Therefore, in order to solve this issue, we aim to compare mortality between patients with low and high modifiable cardiovascular risk factors after PCI. Medline and EMBASE were searched for studies related to these modifiable cardiovascular risk factors. Reported outcome was all-cause mortality after PCI. Risk ratios (RRs) with 95% confidence intervals (CIs) were calculated, and the pooled analyses were performed with RevMan 5.3 software. A total of 100 studies consisting of 884,190 patients (330,068 and 514,122 with high and low cardiovascular risk factors respectively) have been included in this meta-analysis. Diabetes mellitus was associated with a significantly higher short and long-term mortality with RR 2.11; 95% CI: (1.91-2.33) and 1.85; 95% CI: (1.66-2.06), respectively, after PCI. A significantly higher long-term mortality in the hypertensive and metabolic syndrome patients with RR 1.45; 95% CI: (1.24-1.69) and RR 1.29; 95% CI: (1.11-1.51), respectively, has also been observed. However, an unexpectedly, significantly lower mortality risk was observed among the smokers and obese patients. Certain modifiable cardiovascular risk subgroups had a significantly higher impact on mortality after PCI. However, mortality among the obese patients and the smokers showed an unexpected paradox after coronary intervention.

Does an Obesity Paradox Really Exist After Cardiovascular Intervention?: A Systematic Review and Meta-Analysis of Randomized Controlled Trials and Observational Studies

Several studies have shown the existence of an obesity paradox after Percutaneous Coronary Intervention (PCI). However, other studies have shown its absence. This study sought to perform a systematic review and meta-analysis of studies comparing the mortality risk between high body mass index patients and normal weight patients after PCI.We have searched PubMed, Embase, and Chinese medical journal for randomized controlled trials (RCTs) and observational studies published between the year 2000 and 2015 by typing the keywords "percutaneous coronary intervention" and "obesity paradox." The main outcome was "all-cause mortality". RevMan 5.3 software was used to calculate the risk ratio (RR) with 95% confidence interval (CI) to express the pooled effect on discontinuous variables.Twenty-two studies have been included in this meta-analysis consisting of a total of 242,377 patients with 73,143 normal weight patients, 103,608 overweight, and 65,626 obese patients. Younger age, higher cardiovascular risk factors and the intensive use of medications have mainly been observed among obese patients followed by overweight and normal weight patients respectively. In-hospital, 12 months and ≥ 1 year (long-term) mortality risks were significantly lower in the overweight and obese groups with (RR: 0.67; 95% CI: 0.63-0.72, P < 0.00001) and (RR: 0.60; 95% CI: 0.56-0.65, P < 0.00001) respectively in the in-hospital follow-up (RR: 0.62; 95% CI: 0.55-0.71 and 0.57; 95% CI: 0.52-0.63, P < 0.00001) at 12 months, and (RR: 0.70; 95% CI: 0.64-0.76; P < 0.00001) and (RR: 0.80; 95% CI: 0.71-0.91, P = 0.0006) respectively for the long-term follow-up after PCI.This "obesity paradox" does exist after PCI. The mortality in overweight and obese patients is really significantly lower compared to the normal weight patients. However, the exact reasons for this phenomenon need further exploration and research in the future.

Impact of body mass index on the clinical outcomes after percutaneous coronary intervention in patients ≥ 75 years old

BACKGROUND

The impact of body mass index (BMI) on the clinical outcomes after percutaneous coronary intervention (PCI) in patients ≥ 75 years old remained unclear.

METHODS

A total of 1098 elderly patients undergoing PCI with stent implantation were recruited. Patients were divided into four groups by the value of BMI: Underweight (≤ 20.0 kg/m 2 ), normal weight (20.0-24.9 kg/m 2 ), overweight (25.0-29.9 kg/m 2 ) and obese (≥ 30.0 kg/m 2 ). Major clinical outcomes after PCI were compared between the groups. The primary endpoint was defined as in-hospital major adverse cardiovascular events (MACEs), which included death, myocardial infarction (MI) and target vessel revascularization. The secondary endpoint was defined as 1 year death. Logistic regression analysis was performed to adjust for the potential confounders.

RESULTS

Totally, 1077 elderly patients with available BMIs were included in the analysis. Patients of underweight, normal weight, overweight and obese accounted for 5.6%, 45.4%, 41.5% and 7.5% of the population, respectively. Underweight patients were more likely to attract ST-segment elevation MI, and get accompanied with anemia or renal dysfunction. Meanwhile, they were less likely to achieve thrombolysis in MI 3 grade flow after PCI, and receive beta-blocker, angiotensin converting enzyme inhibitor or angiotensin receptor blocker after discharge. In underweight, normal weight, overweight and obese patients, in-hospital MACE were 1.7%, 2.7%, 3.8%, and 3.7% respectively (P = 0.68), and 1 year mortality rates were 5.0%, 3.9%, 5.1% and 3.7% (P = 0.80), without significant difference between the groups. Multivariate regression analysis showed that the value of BMI was not associated with in-hospital MACE in patients at 75 years old.

CONCLUSIONS

The BMI "obese paradox" was not found in patients ≥ 75 years old. It was suggested that BMI may not be a sensitive predictor of adverse cardiovascular events in elderly patients.

Lean mass index, body fat and survival in Chinese patients with coronary artery disease

BACKGROUND

'Obesity paradox' was not consistently observed in Asians with coronary artery disease (CAD).

AIM

The study investigated the association between body composition and outcomes in Chinese patients with CAD.

DESIGN

Cohort study.

METHOD

A total of 3280 patients with angiographically validated CAD were consecutively included. Body fat (BF) percentage and lean mass index (LMI) were evaluated using the Clínica Universidad de Navarra-Body Adiposity Estimator. The rate of mortality from any cause was compared across groups classified by the quartiles of LMI.

RESULTS

During a median period of 24 months, 288 (8.8%) participants died. There was a close association between increasing LMI and reducing mortality rate. However, univariate analyses did not find protective effect of BF on survival. After adjusting for age, sex, diabetes, current smoking, systolic blood pressure, creatinine, white blood cell count, haemoglobin and medication, Cox regression analyses showed that the significant relation between higher quartiles (Q) of LMI and survival benefit (Q4, hazard ratio 0.58 (95% confidence interval: 0.36-0.94) vs. Q3, 0.60 (0.39-0.91) vs. Q2, 0.60 (0.41-0.88) vs. Q1, reference) remained.

CONCLUSION

Low LMI but not BF predicts all-cause mortality in Chinese patients with CAD.

Effect of obesity on coronary atherosclerosis and outcomes of percutaneous coronary intervention: grayscale and virtual histology intravascular ultrasound substudy of assessment of dual antiplatelet therapy with drug-eluting stents

BACKGROUND

Obesity is a cardiovascular risk factor, but the obesity paradox in patients undergoing percutaneous coronary intervention is poorly understood.

METHODS AND RESULTS

Assessment of Dual Antiplatelet Therapy With Drug-Eluting Stents (ADAPT-DES) was a prospective, multicenter study of patients undergoing drug-eluting stent implantation. Overall, 780 patients (916 culprit lesions) were evaluated by grayscale and virtual histology-intravascular ultrasound pre-percutaneous coronary intervention. Poststenting intravascular ultrasound was done in 780 patients (894 treated lesions). Patients were divided into body mass index (BMI) tertiles. The high-BMI group had more diabetes mellitus, hypertension, and hyperlipidemia and more frequent plaque ruptures compared with the low-BMI group. At the minimal lumen area site, the high-BMI group had a larger plaque area (11.7 [11.0-12.4] versus 9.8 [9.3-10.4] mm(2)) and a greater plaque burden (77.3% [76.1%-78.5%] versus 74.4% [73.1%-75.8%]) compared with the low-BMI group; however, a larger external elastic membrane area (14.6 [13.8-15.3] versus 12.7 [12.1-13.3] mm(2)) resulted in a similar minimal lumen area compared with the low-BMI group. Post stenting, the high-BMI group had a significantly larger stent area versus the lower-BMI group. At 1-year follow-up, the high-BMI group was associated with less clinically driven target lesion revascularization compared with the low-BMI group in both the overall and the propensity-matched cohorts.

CONCLUSIONS

A high BMI was associated with a greater plaque burden; however, a larger external elastic membrane preserved lumen dimensions and was associated with a larger stent area during intravascular ultrasound-guided stent implantation. Thus, despite more comorbidities, greater plaque burden, and more plaque rupture, a high BMI was not associated with worse outcomes after drug-eluting stent implantation.

CLINICAL TRIAL REGISTRATION URL

http://www.clinicaltrials.gov. Unique identifier: NCT00638794.

Obesity and coronary artery disease: evaluation and treatment

With the increasing prevalence of obesity, clinicians are now facing a growing population of patients with specific features of clinical presentation, diagnostic challenges, and interventional, medical, and surgical management. After briefly discussing the effect of obesity on atherosclerotic burden in this review, we will focus on strategies clinicians might use to ensure better outcomes when performing revascularization in obese and severely obese patients. These patients tend to present comorbidities at a younger age, and their anthropometric features might limit the use of traditional cardiovascular risk stratification approaches for ischemic disease. Alternative techniques have emerged, especially in nuclear medicine. Positron emission tomography-computed tomography might be the diagnostic imaging technique of choice. When revascularization is considered, features associated with obesity must be considered to guide therapeutic strategies. In percutaneous coronary intervention, a radial approach should be favoured, and adequate antiplatelet therapy with new and more potent agents should be initiated. Weight-based anticoagulation should be contemplated if needed, with the use of drug-eluting stents. An "off-pump" approach for coronary artery bypass grafting might be preferable to the use of cardiopulmonary bypass. For patients who undergo bilateral internal thoracic artery grafting, harvesting using skeletonization might prevent deep sternal wound infections. In contrast to percutaneous coronary intervention, lower surgical bleeding has been observed when lean body mass is used for perioperative heparin dose determination.

The incidence of acute myocardial infarction in relation to overweight and obesity: a meta-analysis

INTRODUCTION

Epidemiological evidence suggests that overweight and obesity have been associated with acute myocardial infarction (AMI). However, data on this issue are controversial. This study aims to use meta-analysis to determine whether overweight and obesity are related to AMI.

MATERIAL AND METHODS

We searched PubMed and Embase databases up to October 23(rd), 2013 for related literature. The association of overweight and obesity with AMI was assessed by odd ratio (OR) with 95% confidence interval (CI) as the effect size. Then subgroup analysis was performed according to gender, area and study type.

RESULTS

Five primary studies (one cohort study and four case-control studies) were included in this meta-analysis involving 36 803 participants, 14 883 of whom had an AMI. There was a significant association between overweight and AMI (OR = 1.27, 95% CI: 1.21-1.33, p < 0.001). Similar results revealed a relation between obesity and AMI (OR = 1.22, 95% CI: 1.07-1.40, p = 0.003). Subgroup analysis showed that overweight and obesity were positively associated with AMI risk except for obese subjects in Europe. There was no publication bias (Begg's test p = 0.972, Egger's test p = 0.858).

CONCLUSIONS

Both overweight and obesity increased the incidence of AMI, and it is necessary to control weight to prevent AMI. A large number of studies is needed to explore the mechanisms that link overweight and obesity with AMI.

Obesity paradox in different populations: evidence and controversies

ABSTRACT: An inverse association between BMI and mortality has been reported in patients with coronary heart disease and heart failure. This ‘obesity paradox‘ has recently been reported in other disease states, including stroke, hypertension, incident diabetes, atrial fibrillation, hemodialysis and transcatheter aortic valve replacement. Cardiorespiratory fitness influences the obesity paradox and this inverse association may be present only in individuals with low fitness levels. Intentional weight loss, exercise training and improving lean mass are important and should be advised to all patients. Recent studies have also explored the association between measures of central obesity and direct measures of body fat with mortality. This review will summarize the evidence, controversies and mechanisms associated with the puzzling obesity paradox.

The impact of obesity on risk factors and prevalence and prognosis of coronary heart disease-the obesity paradox

Obesity is associated with a host of cardiovascular risk factors and its prevalence is rising rapidly. Despite strong evidence that obesity predisposes to the development and progression of coronary heart disease (CHD), numerous studies have shown an inverse relationship between various measures of obesity (most commonly body mass index) and outcomes in established CHD. In this article we review the evidence surrounding the ≪obesity paradox≫ in the secondary care of CHD patients and the CHD presentations where a paradox has been found. Finally we discuss the impact of cardiorespiratory fitness and a number of mechanisms which may offer potential explanations for this puzzling phenomenon.