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Background Progressive cardiac remodeling and worsening myocardial function over time have been proposed as potential mediators of heart failure in obesity. Methods and Results We serially assessed cardiac structure and function in 254 subjects participating in a longitudinal study of obesity. Demographic, clinical, laboratory, and echocardiographic features were determined at baseline and 2-, 6-, and 11-year follow-up. We measured body mass index (BMI) exposure as the area under the curve of the BMI at each of the 4 visits. At enrollment, mean age of the subjects was 47 years, 79% were women, mean BMI was 44 kg/m 2 , 26% had diabetes mellitus, 48% had hypertension, and 53% had hyperlipidemia. Between baseline and 11 years, BMI increased by 1.1 and 0.3 kg/m 2 in men and women, respectively. There were modest increases in left ventricular (LV) end-diastolic volume, LV mass, and left atrial volume, and significant decreases in early/late mitral diastolic flow velocity ratio and E wave deceleration time. However, there were no significant changes in LV ejection fraction or ratio of early mitral diastolic flow velocity/early mitral annular velocity, whereas right ventricular fractional area change increased. Significant predictors of the change in LV mass were male sex, baseline BMI, BMI area under the curve, and change in LV stroke volume, but not smoking, hypertension, or diabetes mellitus. Conclusions In long-standing, persistent severe obesity, there was evidence of cardiac remodeling over a period of 11 years, but no clear worsening of systolic or diastolic function. Measures of remodeling were most strongly related to BMI. The observed changes might predispose to heart failure with preserved ejection fraction, but are not classic for an evolving dilated cardiomyopathy.

Obesity and low cardiorespiratory fitness are both established predictors of cardiovascular disease morbidity and mortality. Whether the protective effects of fitness outweigh the deleterious effects of obesity, however, remains a topic of debate. To extend knowledge of the relative influence of fitness and fatness on cardiovascular disease outcomes, however, attention must be paid to measurement quality. Eliminating inherent bias of self-report and including the highest quality assessments of cardiorespiratory fitness and fatness simultaneously are imperative for head-to-head comparisons. Studies must move beyond body mass index and total body fat percentage to differentiate the heterogenous effects of various adipose tissue depots on cardiovascular risk. Imaging techniques that measure visceral adiposity and other risk-laden ectopic adipose depots while also quantifying cardioprotective adipose depots such as lower body subcutaneous fat and even non-adipose tissues such as skeletal muscle may further illuminate the influence of body composition on cardiovascular health. This review underscores key studies within a large body of literature that provide the foundation for the fit-vs.-fat debate in the context of cardiovascular disease risk, and identifies important considerations for future research.

Both obesity and hepatitis B virus (HBV) infection increase the risk of death. We investigate the association between general and central obesity and all-cause mortality among adult Taiwanese HBV versus non-HBV carriers.A total of 19,850 HBV carriers and non-hepatitis C virus (HCV) carriers, aged 20 years and older at enrollment in 1998 to 1999 in Taiwan, were matched to 79,400 non-HBV and non-HCV carriers (1:4). Cox proportional-hazards models were used to estimate the relative risks for all-cause mortality during a maximum follow-up period of 10 years. Four obesity-related anthropometric indices-body mass index (BMI), waist circumference, waist-to-hip ratio, and waist-to-height ratio-were the main variables of interest.During the follow-up period, 628 and 2366 participants died among HBV and non-HBV carriers, respectively. Both underweight and general obesity were associated with an increased risk of death. The highest risk of all-cause death in relation to BMI was found in the HBV carriers with underweight (BMI <18.5 kg/m2) and non-HBV carriers with obesity (BMI ≥30 kg/m2). The lowest risks of all-cause death in relation to abdominal adiposity were found at the third quartiles of waist circumference, waist-to-hip ratio, and waist-to-height ratio among HBV carriers, but in the second quartiles among non-HBV carriers. For those with pre-existing liver disease among HBV carriers, patients with underweight have higher risk of death than those with obesity.Hepatitis B virus carriers with underweight have higher risk of death than non-HBV carriers. HBV carriers with mild abdominal obesity have the lowest risk of death, but not in the non-HBV carriers.

Whereas the initial focus of bariatric surgery primarily focused on weight loss and was considered by many clinicians and the public as a cosmetic-driven procedure, this surgical therapy is now recognized as a successful approach to reducing cardiovascular disease risk and the only substantial and sustainable weight loss treatment for most severely obese patients. In addition, as a result of the multiple metabolic-related benefits associated with bariatric surgery, efforts to understand physiologic and biochemical mechanisms have led to a dramatic increase in scientific discovery. This review focuses on bariatric research conducted during the past two decades in relation to cardiovascular disease risk and the effects of this surgical therapy on diabetes. Cardiovascular and diabetes mortality and morbidity associated with bariatric surgery are reviewed. The opportunity for bariatric (and/or metabolic) surgery to provide a preventive strategy for cardiovascular disease and diabetes as well as treatment therapy is presented for clinical consideration.

Context: Extreme obesity is associated with health and cardiovascular disease risks. Although gastric bypass surgery induces rapid weight loss and ameliorates many of these risks in the short term, long-term outcomes are uncertain., Objective: To examine the association of Roux-en-Y gastric bypass (RYGB) surgery with weight loss, diabetes mellitus, and other health risks 6 years after surgery., Design, Setting, and Participants: A prospective Utah-based study conducted between July 2000 and June 2011 of 1156 severely obese (body mass index [BMI] ≥ 35) participants aged 18 to 72 years (82% women; mean BMI, 45.9; 95% CI, 31.2-60.6) who sought and received RYGB surgery (n = 418), sought but did not have surgery (n = 417; control group 1), or who were randomly selected from a population-based sample not seeking weight loss surgery (n = 321; control group 2)., Main Outcome Measures: Weight loss, diabetes, hypertension, dyslipidemia, and health-related quality of life were compared between participants having RYGB surgery and control participants using propensity score adjustment., Results: Six years after surgery, patients who received RYGB surgery (with 92.6% follow-up) lost 27.7% (95% CI, 26.6%-28.9%) of their initial body weight compared with 0.2% (95% CI, -1.1% to 1.4%) gain in control group 1 and 0% (95% CI, -1.2% to 1.2%) in control group 2. Weight loss maintenance was superior in patients who received RYGB surgery, with 94% (95% CI, 92%-96%) and 76% (95% CI, 72%-81%) of patients receiving RYGB surgery maintaining at least 20% weight loss 2 and 6 years after surgery, respectively. Diabetes remission rates 6 years after surgery were 62% (95% CI, 49%-75%) in the RYGB surgery group, 8% (95% CI, 0%-16%) in control group 1, and 6% (95% CI, 0%-13%) in control group 2, with remission odds ratios (ORs) of 16.5 (95% CI, 4.7-57.6; P < .001) vs control group 1 and 21.5 (95% CI, 5.4-85.6; P < .001) vs control group 2. The incidence of diabetes throughout the course of the study was reduced after RYGB surgery (2%; 95% CI, 0%-4%; vs 17%; 95% CI, 10%-24%; OR, 0.11; 95% CI, 0.04-0.34 compared with control group 1 and 15%; 95% CI, 9%-21%; OR, 0.21; 95% CI, 0.06-0.67 compared with control group 2; both P < .001). The numbers of participants with bariatric surgery-related hospitalizations were 33 (7.9%), 13 (3.9%), and 6 (2.0%) for the RYGB surgery group and 2 control groups, respectively., Conclusion: Among severely obese patients, compared with nonsurgical control patients, the use of RYGB surgery was associated with higher rates of diabetes remission and lower risk of cardiovascular and other health outcomes over 6 years.

Background: The ratio of limb fat to trunk fat (LF/TF) is associated with markers of cardiometabolic risk in elderly men and women. It is unknown if LF/TF is associated with cardiometabolic risk beyond that explained by LF and TF independently., Methods: Participants included abdominally obese men (n = 58) and women (n = 78) between 60 and 80 years of age. Regional adiposity was quantified using magnetic resonance imaging. Insulin resistance, fasting glucose, high-density lipoprotein (HDL) cholesterol, plasma triglycerides, and adiponectin were determined using standard procedures., Results: After control for potential confounders, TF was positively associated with fasting glucose, insulin resistance, and plasma triglycerides and negatively associated with HDL cholesterol and adiponectin (p < or = .05). These associations were strengthened after further control for LF (p < .05), with the exception of adiponectin in men (p > .05). After control for potential confounders, LF was negatively associated with adiponectin in men (p < .05) but not with any other marker of cardiometabolic risk (p > .05). After further control for TF, LF was negatively associated with plasma triglycerides and positively associated with HDL cholesterol in both genders combined (p < .05) and with adiponectin in women (p < .05) but not in men (p > .05). LF/TF was not associated with any marker of cardiometabolic risk after control for LF and TF., Conclusion: These results suggest that it is the absolute, rather than relative, amounts of LF and TF that have the greatest influence on cardiometabolic risk in elderly men and women.

Background: Authorities advocate that resistance and aerobic exercise are essential for reducing risk factors for chronic disease and disability in older adults. However, the incremental effects of combined resistance and aerobic exercise compared with either modality alone on risk factors for disease and disability is generally unknown., Methods: Participants were 136 sedentary, abdominally obese older men and women recruited from September 30, 2002, through November 15, 2006, at Queen's University. Participants were randomized to 1 of the following 4 groups for 6 months: resistance exercise, aerobic exercise, resistance and aerobic exercise (combined exercise), or nonexercise control. Primary outcomes were analyzed by an intent-to-treat model and included changes in insulin resistance by hyperinsulinemic-euglycemic clamp and functional limitation using the average change in 4 tests combined (average z score)., Results: After controlling for age, sex, and baseline value, insulin resistance improved compared with controls in the aerobic exercise and the combined exercise groups but not in the resistance exercise group. Improvement (mean [SE]) in the combined exercise group was greater than in the resistance exercise group (9.2 [1.3] vs 1.8 [1.3] mg/mL/microIU per kilogram of skeletal muscle per minute x100 [P < .001]) but not in the aerobic exercise group (9.2 [1.3] vs 6.5 [1.3] mg/mL/microIU per kilogram of skeletal muscle per minute x100 [P = .46]). Functional limitation improved significantly in all groups compared with the control group. Improvement in the combined exercise group was greater than in the aerobic exercise group (0.5 [0.1] vs -0.0 [0.1]; standard units, z score [P = .003]) but not in the resistance exercise group. Improvement in the resistance exercise group was not different from the aerobic exercise group., Conclusion: The combination of resistance and aerobic exercise was the optimal exercise strategy for simultaneous reduction in insulin resistance and functional limitation in previously sedentary, abdominally obese older adults., Trial Registration: clinicaltrials.gov Identifier: NCT00520858.

Whether dietary fat influences the interaction between liver fat, visceral adipose tissue (VAT), and metabolic risk is unclear. Thus, we sought to determine the independent associations between 1 and 10 d dietary fat intake, liver fat, and VAT on insulin sensitivity using a cross-sectional design. Liver fat score (LFS) was assessed by computed tomography and VAT by magnetic resonance imaging in 42 abdominally obese older men. Insulin sensitivity was measured by the hyperinsulinemic-euglycemic clamp technique. Diet composition was determined from self-recorded diet records for 1 and 10 d preceding the assessment of LFS. LFS was positively associated with the 10 d average fat and alcohol intake, but not with any 1 d average dietary variables. VAT (r = -0.36) and LFS (r = -0.32) were both negatively correlated with insulin sensitivity (p < 0.05). When LFS and VAT were entered in the same model, only VAT was an independent predictor of insulin sensitivity (p < 0.05). Control for the average 10 d alcohol consumption and fat intake improved the association between insulin sensitivity and LFS (from r = -0.32, p > 0.10 to r = -0.49, p < 0.05), but not VAT. In fact, after control for the 10 d dietary variables, both LFS and VAT were independent predictors of insulin sensitivity (p < 0.05). This was not true for any of the 1 d dietary intake variables. In conclusion, liver fat is associated with dietary fat intake and alcohol consumption over 10 d, but not 1 d. Furthermore, dietary habits may influence the relationship between liver fat and insulin sensitivity.

It is unclear whether chronic exercise without caloric restriction or weight loss is a useful strategy for obesity reduction in obese men with and without Type 2 diabetes (T2D). We examined the effects of exercise without weight loss on total and regional adiposity and skeletal muscle mass and composition in lean men and in obese men with and without T2D. Twenty-four men participated in 13 wk of supervised aerobic exercise, five times per week for 60 min at a moderate intensity (approximately 60% peak oxygen uptake). Total and regional body composition was measured by magnetic resonance imaging. Skeletal muscle composition was determined using computed tomography. Cardiorespiratory fitness was assessed using a graded maximal treadmill test. Body weight did not change within any group in response to exercise (P > 0.1). Significant reductions in total, abdominal subcutaneous, and visceral fat were observed within each group (P < 0.01). The reduction in total and abdominal subcutaneous fat was not different (P > 0.1) between groups; however, the reduction in visceral fat was greater (P < 0.01) in the obese and T2D groups by comparison to the lean group. A significant (P < 0.01) increase in total skeletal muscle, high-density muscle area, and mean muscle attenuation was observed independent of group, and these changes were not different between groups (P > 0.1). Accordingly, whole body fat-to-muscle ratio was increased (P < 0.01) independent of groups. In conclusion, regular exercise without weight loss is associated with a substantial reduction in total and visceral fat and in skeletal muscle lipid in both obesity and T2D.