Metabolic Profile and Exercise Capacity Outcomes

Obesity and Cardiovascular Risk: Systematic Intervention Is the Key for Prevention

Obesity is a serious public health issue and associated with an increased risk of cardiovascular disease events and mortality. The risk of cardiovascular complications is directly related to excess body fat mass and ectopic fat deposition, but also other obesity-related complications such as pre-type 2 diabetes, obstructive sleep apnoea, and non-alcoholic fatty liver diseases. Body mass index and waist circumference are used to classify a patient as overweight or obese and to stratify cardiovascular risk. Physical activity and diet, despite being key points in preventing adverse events and reducing cardiovascular risk, are not always successful strategies. Pharmacological treatments for weight reduction are promising strategies, but are restricted by possible safety issues and cost. Nonetheless, these treatments are associated with improvements in cardiovascular risk factors, and studies are ongoing to better evaluate cardiovascular outcomes. Bariatric surgery is effective in reducing the incidence of death and cardiovascular events such as myocardial infarction and stroke. Cardiac rehabilitation programs in obese patients improve cardiovascular disease risk factors, quality of life, and exercise capacity. The aim of this review was to critically analyze the current role and future aspects of lifestyle changes, medical and surgical treatments, and cardiac rehabilitation in obese patients, to reduce cardiovascular disease risk and mortality, and to highlight the need for a multidisciplinary approach to improving cardiovascular outcomes.

Weight Loss and Its Predictors During Participation in Cardiac Rehabilitation

We aimed to assess the prevalence and magnitude of clinically meaningful weight loss among cardiac rehabilitation (CR) participants who were overweight or obese and identify its predictors. We analyzed subjects with body mass index (BMI) ≥25 who were enrolled in a 12-week CR outpatient program from January 1, 2015, to December 31, 2019, and had paired pre- and post-CR weight data. Patients who lost 3% or more of their body weight by the end of the program were compared with the remaining participants. Multivariable logistic regression was used to determine predictors of weight loss. Overall, 129 of 485 subjects (27%) with overweight or obesity reduced their weight by at least 3% (average percent weight change: -5.0% ± 1.8% vs -0.02% ± 2.2%, average weight change: -10.9 ± 5.0 vs -0.1 ± 4.4 pounds, and average BMI change: -1.7 ± 0.7 vs -0.02 ± 0.7 kg/m²). Compared with the remaining 356 patients, those who achieved the defined weight loss were younger (p = 0.016) and had higher baseline weight (p = 0.002) and BMI (p <0.001). The weight loss group tended to be enrolled more likely for an acute myocardial infarction or percutaneous coronary intervention (p <0.001) and less likely for coronary artery bypass grafting (p = 0.001) or a heart valve procedure (p = 0.05). By the end of the CR program, the weight loss group demonstrated a greater increase in Rate Your Plate - Heart score (7 [3, 11] vs 4 [1, 8]; p <0.001) and a greater decrease in triglycerides (-20 ± 45 vs -7 ± 55 mg/dL; p = 0.026) and glycated hemoglobin (-0.1 [-0.5, 0.1] vs 0.1 [-0.3, 0.4] %; p = 0.05, among patients with diabetes or prediabetes). In a multivariable logistic regression model, baseline predictors of clinically meaningful weight loss included higher BMI and not being enrolled for a surgical CR indication (p = 0.001). In conclusion, throughout 12 weeks of CR participation, 129 of 485 subjects (27%) with BMI ≥25 had a 3% or more reduction in body weight. Patients with higher baseline BMI and participants without a surgical enrollment diagnosis were more likely to achieve the defined weight loss. Efforts to improve CR referral and enrollment for eligible patients with overweight and obesity should be encouraged, and suitable and efficient weight reduction interventions in CR settings need to be further studied.

Physical Activity and Sedentary Behavior in Cardiac Rehabilitation: Does Body Mass Index Matter?

OBJECTIVE

The purpose of this study was to investigate the relationship between body mass index (BMI) class and physical activity and sedentary behavior in patients with acute coronary syndrome (ACS) during cardiac rehabilitation (CR).

METHODS

This study was a secondary analysis of the OPTICARE trial. Physical activity and sedentary behavior were measured in participants with ACS (n = 359) using actigraphy at baseline, directly after completion of a multidisciplinary 12-week exercise-based CR program and 9 months thereafter. Outcome measures were step count and duration of time (percentage of wear time) spent in light physical activity, moderate-to-vigorous physical activity, and sedentary behavior. Participants were classified as normal weight (BMI = 18.5-24.99 kg/m2; n = 82), overweight (BMI = 25.0-29.99 kg/m2; n = 182), or obese (BMI ≥ 30.0 kg/m2; n = 95). Linear mixed-effects models were applied to study the relationship between BMI class and physical activity and sedentary behavior.

RESULTS

At the start of CR, compared with participants with normal weight, participants with obesity made on average 1.11 steps fewer per minute (952 steps/d), spent 2.9% (25 min/d) less time in light physical activity, and spent 3.31% (28 min/d) more time in sedentary behavior. Participants of all BMI classes improved their physical activity and sedentary behavior levels similarly during CR, and these improvements were maintained after completion of CR.

CONCLUSION

Participants with ACS who had obesity started CR with a less favorable physical activity and sedentary behavior profile than that of participants with normal weight. Because all BMI classes showed similar improvement during CR, this deficit was preserved.

IMPACT

This study indicates that reconsideration of the CR program in the Netherlands for patients with ACS and obesity is warranted, and development of more inclusive interventions for specific populations is needed. A new program for people with obesity should include added counseling on increasing physical activity and preventing sedentary behavior to facilitate weight loss and reduce mortality risk.

LAY SUMMARY

People with ACS who have obesity are less active and sit more than individuals with normal weight, both during and after CR. This study suggests that CR needs to be changed to help individuals increase their physical activity to help them lose weight and reduce their risk of death.

Psychosocial and Cardiometabolic Health of Patients With Differing Body Mass Index Completing Cardiac Rehabilitation

BACKGROUND

It remains unclear whether cardiac rehabilitation (CR) provides similar benefits to patients with varying levels of body mass index (BMI). We assessed the psychosocial and cardiometabolic health of patients with increased BMI who completed CR.

METHODS

The records of 582 patients who completed a 3-month outpatient CR program were analyzed. On the basis of their BMI at baseline, patients were categorized as normal (18.5-24.9 kg/m²), overweight (25.0-29.9 kg/m²), obese (30.0-34.9 kg/m²), or severely obese (≥ 35.0 kg/m²). Analysis of covariance was used to compare health-related quality of life (ie, Physical Component Summary [PCS] and Mental Component Summary scores), anxiety, depression, and cardiometabolic health indicators between BMI categories after CR.

RESULTS

At baseline, patients with severe obesity, when compared with those with normal BMI, had lower PCS scores (39.7 ± 8.5 vs 44.4 ± 8.4, P < 0.001), elevated levels of anxiety (7.0 ± 3.7 vs 4.8 ± 3.2, P = 0.001) and depression (5.5 ± 4.4 vs 3.4 ± 3.7, P < 0.001), higher glycated hemoglobin A1C (6.5 ± 1.1 vs 5.6 ± 0.7%, P < 0.001) and triglycerides (1.6 ± 0.5 vs 1.1 ± 0.4 mmol/L, P < 0.001), and lower high-density lipoprotein cholesterol (1.1 ± 0.3 vs 1.2 ± 0.4 mmol/L, P = 0.006). After CR, notwithstanding a greater percent weight reduction in obesity (-3.5% ± 6.9% vs +1.1% ± 7.0%, P = 0.002) and severe obesity (-6.5% ± 6.9% vs +1.1% ± 7.0%, P < 0.001), smaller improvements in PCS scores were seen in the obese (4.1 ± 7.4 vs 6.9 ± 7.6, P = 0.011) and severely obese (4.1 ± 7.6 vs 6.9 ± 7.6, P = 0.039) when compared with those with normal BMI.

CONCLUSIONS

Poorer psychosocial and cardiometabolic health at baseline coupled with smaller improvements in the PCS score suggest that patients with obesity and severe obesity will benefit from enhanced care in the CR setting.

All-cause mortality of metabolically healthy or unhealthy obese: risk stratification using myocardial perfusion imaging

Introduction

There is still controversy about the favorable prognosis of "metabolically healthy" (MH) obese. This study evaluated mortality and the use of myocardial perfusion scintigraphy (MPS) for risk stratification of MH or metabolically unhealthy (MU) obese or nonobese patients.

Material and methods

Patients without dyslipidemia, hypertension, or diabetes were considered MH, and those with ≥ 1 of these risk factors were considered MU. The MPS was categorized as normal, abnormal or ischemic. Patients were followed for 4.0 ±1.0 years for all-cause death.

Results

Of 2450 patients, 613 were obese. The MH obese patients less often had ischemia than MU obese, but there was no significant difference in the prevalence of ischemia compared to all nonobese. The annualized death rate of MH obese was 1.3% and of nonobese 1.0% (p = 0.4). An abnormal MPS and the MU status were independently associated with death, with hazard ratios of 1.85 and 1.72, respectively. A normal MPS identified patients with low risk among all subgroups; annualized rates of death were 1.0%, 1.1% and 1.0% for all nonobese, MH obese and MU obese, respectively (p = 0.63).

Conclusions

The annualized death rate of MH obese patients was not significantly different from that of nonobese individuals. Myocardial perfusion scintigraphy was able to stratify prognosis in the overall patient population. These data may be helpful to identify high-risk individuals, thereby improving patient management.

"Metabolically healthy" obesity: Prevalence, clinical features and association with myocardial ischaemia

OBJECTIVE

To evaluate the prevalence of the "metabolically healthy" (MH) or "metabolically unhealthy" (MU) obesity phenotypes and their association with cardiorespiratory fitness and inducible myocardial ischaemia.

METHODS

Individuals without known coronary artery disease undergoing myocardial perfusion single-photon emission computed tomography (MPS) were studied. Those without dyslipidemia, hypertension, or diabetes were considered MH, and when ≥1 of these was present, MU status was considered present. Summed stress and difference perfusion scores (SSS and SDS, respectively) were calculated; a SDS >1 defined ischaemic MPS.

RESULTS

MH patients were 35.0% of the nonobese population and 23.5% of the obese (p<0.001). The prevalence of ischaemia was not significantly different between MH patients with obesity or MH patients without obesity (10.9% vs 9.1%, p=0.3), except for patients with body mass index ≥40kg/m² (21.9%). MH obese patients were less frequently able to exercise and had lower exercise capacity than the nonobese patients.

CONCLUSIONS

The prevalence of myocardial ischaemia was not significantly different between MH obese or nonobese individuals, supporting the concept of the "metabolically healthy obesity". However, there are other factors involved, such as the ability to exercise, that influence the risk of myocardial ischaemia, limiting the "safety" of that obesity phenotype.

Effect of cardiac rehabilitation on metabolic syndrome and its components: A systematic review and meta-analysis

BACKGROUND

Although the effect of cardiac rehabilitation (CR) on cardiovascular disease (CVD) prognosis has been well-documented by several systematic reviews, none have focused on the effect of CR on metabolic syndrome (MetS) and its related components. Therefore, the present systematic review and meta-analysis was conducted to assess the effect of CR on MetS and its components.

MATERIALS AND METHODS

PubMed, SCOPUS, Cochrane library, and Google Scholar database were searched up to February 2014 with no date and language restrictions. The random effects model was used to assess the overall effect of CR on MetS prevalence and the change in metabolic or anthropometric measures.

RESULTS

Fifteen studies with 19,324 subjects were included in the present systematic review and meta-analysis. Our analysis showed that the CR could significantly reduce MetS prevalence [reduction rate: 0.25, 95% confidence interval (CI): 0.21, 0.3, P value <0.001; P value for heterogeneity <0.001, I-squared: 86.2%]. Additionally, results showed the protective role of CR on all MetS components including high density lipoprotein cholesterol [mean difference (MD): 2.13 mg/dL, 95% CI: 1.17, 3.1], triglyceride (MD: -27.45 mg/dL, 95% CI: -36.92, -17.98), systolic blood pressure (SBP) (MD: -6.20 mmHg, 95% CI: -8.41, -3.99), diastolic blood pressure (DBP) (MD: -2.53 mmHg, 95% CI: -3.64, -1.41), fasting blood sugar (FBS) (MD: -6.42 mg/dL, 95% CI: -6.85, -5.99), and waist circumference (WC) (MD: -2.25 cm, 95% CI: -3.15, -1.35).

CONCLUSION

CR has resulted in improvement in MetS and its entire components, and could be considered as a useful tool for MetS patients, especially among those with CVD.

Degree and Direction of Change of Body Weight in Cardiac Rehabilitation and Impact on Exercise Capacity and Cardiac Risk Factors

Cardiac rehabilitation (CR) improves functional capacity and reduces mortality in patients with cardiovascular disease. It also improves cardiovascular risk factors and aids in weight reduction. Because of the increase in morbidly obese patients with cardiovascular disease, the prevalence of obesity and patterns of weight change in those undergoing CR merit fresh study. We studied 1,320 participants in a 12-week CR program at our academic medical center. We compared 5 categories: 69 class III obese (body mass index [BMI] ≥40) patients, 128 class II obese patients (BMI 35.0 to 39.9), 318 class I obese patients (BMI 30.0 to 34.9), 487 overweight patients (BMI 25.0 to 29.9), and 318 normal weight patients (BMI 18.5 to 24.9). Exercise capacity in METs, weight, blood pressure, and fasting lipid profile were measured before and after CR. Overall, 131 patients gained weight, 827 had no significant weight change, and 363 lost weight (176 lost 3% to 5% of their baseline weight, 161 lost 5% to 10%, and 26 lost >10%). Exercise capacity, blood pressure, and low-density lipoprotein cholesterol improved in all patients. Class III obese patients had the smallest improvement in peak METs (p <0.001), but the greatest weight loss. Patients who lost >10% of their baseline weight had the greatest improvements in exercise capacity, low-density lipoprotein, and triglycerides. In conclusion, after CR, a minority of patients lost weight. Most patients had no significant weight change and some even gained weight. The greatest loss was seen in class III obese patients. All patient groups showed improvements in exercise capacity and risk factors, regardless of the direction or degree of weight change.

The effects of horseback riding on body mass index and gait in obese women

[Purpose] The aim of this study was to examine the effect of horseback riding on body mass index (BMI) and gait in obese women. [Subjects and Methods] Twenty-four obese women residing in Seoul and Gyeonggi-do were randomly divided into a horseback riding group and a walking group and conducted their respective exercises 3 times a week for 8 weeks. [Results] Step length increased significantly and BMI and width of the base of support significantly decreased in both groups. A comparison of BMI and width of the base of support after the intervention between the two groups revealed that the horseback riding group showed larger decreases than the walking group. [Conclusion] The result of this study indicated that the horseback riding may improve gait ability and obesity.

Factors that influence obesity, functional capacity, anxiety and depression outcomes following a Phase III cardiac rehabilitation programme

AIMS AND OBJECTIVES

To examine changes in functional capacity, anxiety, depression and BMI in patients who completed a cardiac rehabilitation programme and to determine the influencing factors.

BACKGROUND

While the effectiveness of cardiac rehabilitation is long established, more studies are needed to examine the combined effectiveness of this multicomponent intervention and the factors that influence this in the changed profile of patients currently attending cardiac rehabilitation.

DESIGN

The study was a longitudinal retrospective study of patients following a six- or eight-week Phase III cardiac rehabilitation programme.

METHODS

The study recruited 154 patients. Functional capacity, anxiety, depression, weight, waist circumference and BMI were assessed at the beginning and end of cardiac rehabilitation. t-tests were used to assess changes over time, and multivariate regression analysis was used to determine the influence of factors on these changes.

RESULTS

Significant improvements were seen in functional capacity, waist circumference, weight and BMI, but not in depression and anxiety. Multivariate analysis revealed that being younger and less fit was associated with greater improvements in functional capacity while reason for referral, gender, depression or BMI did not influence improvements in functional capacity. Models testing the influence of the factors on BMI, anxiety and depression were not significant.

CONCLUSION

Cardiac rehabilitation is still an effective method to instigate changes in cardiac risk factors despite the changes in patients profile attending programmes.

RELEVANCE TO CLINICAL PRACTICE

Continued encouragement of the historically less typical patients to participate in cardiac rehabilitation is needed as reason for referral, gender, depression or BMI did not influence improvements in functional capacity. Despite psychosocial components within the programme, no significant improvements were observed over cardiac rehabilitation in depression or anxiety. While effectiveness was observed, there is room for further optimisation of practice and research by employing and documenting clearly the use of behavioural techniques.

Yoga training improves metabolic parameters in obese boys

Yoga has been known to have stimulatory or inhibitory effects on the metabolic parameters and to be uncomplicated therapy for obesity. The purpose of the present study was to test the effect of an 8-week of yoga-asana training on body composition, lipid profile, and insulin resistance (IR) in obese adolescent boys. Twenty volunteers with body mass index (BMI) greater than the 95th percentile were randomly assigned to yoga (age 14.7±0.5 years, n=10) and control groups (age 14.6±1.0 years, n=10). The yoga group performed exercises three times per week at 40~60% of heart-rate reserve (HRR) for 8 weeks. IR was determined with the homeostasis model assessment of insulin resistance (HOMA-IR). After yoga training, body weight, BMI, fat mass (FM), and body fat % (BF %) were significantly decreased, and fat-free mass and basal metabolic rate were significantly increased than baseline values. FM and BF % were significantly improved in the yoga group compared with the control group (p<0.05). Total cholesterol (TC) was significantly decreased in the yoga group (p<0.01). HDL-cholesterol was decreased in both groups (p<0.05). No significant changes were observed between or within groups for triglycerides, LDL-cholesterol, glucose, insulin, and HOMA-IR. Our findings show that an 8-week of yoga training improves body composition and TC levels in obese adolescent boys, suggesting that yoga training may be effective in controlling some metabolic syndrome factors in obese adolescent boys.

The effect of the cardiac rehabilitation program on obese and non-obese females with coronary heart disease

INTRODUCTION

Obesity is strongly associated with coronary heart disease and it is known as an independent risk factor. So, the aim of this study was to investigate the effects of phase II comprehensive cardiac rehabilitation program on obesity indexes, functional capacity, lipid profiles, and fasting blood sugar in obese and non-obese female patients with coronary heart disease and to compare changes in these groups.

MATERIALS AND METHODS

Two hundred and five women with coronary heart disease participated in our study. At the beginning of study, body mass index, functional capacity, and lipid profiles and fasting blood sugar were evaluated; then, these patients were divided into two groups, patients who had BMI≥30 were known as obese and who had BMI<30 were known as non-obese patients. All of them completed the period of cardiac rehabilitation program, and 2 months later, all risk factors were examined for the second time in each group. Data were analyzed with SPSS software version 15. For comparing the mean of outcomes, independent t-tests and paired t-tests were used.

RESULTS

Data revealed that unless in weight (P=0.00) and functional capacity (P=0.001), there were no significant differences in obese and non-obese female patients, at baseline. As a result of the cardiac rehabilitation program, both groups had significant improvement in functional capacity (P=0.00), weight reduction (P=0.00), triglyceride (P=0.01 and P=0.02, respectively), low-density lipoprotein cholesterol (P=0.01), and low-density lipoprotein cholesterol/high-density lipoprotein cholesterol ratio (P=0.00 and P=0.003, respectively). As well, significant improvement was observed in high-density lipoprotein (P=0.01) only in obese female, and non-obese female had significant differences in total cholesterol (P=0.003). However, there were not significant changes in total cholesterol (P=0.05) and fasting blood sugar (P=0.09) in obese female. Also, non-obese females didn't have favorable differences in high-density lipoprotein cholesterol (P=0.23) and fasting blood sugar (P=0.13). In addition, comparing two groups didn't show any significant differences in each risk factors except BMI (P=0.03).

CONCLUSION

Our study revealed that comprehensive cardiac rehabilitation program results in significant improvement in cardiovascular risk factors and functional capacity at all levels of BMI in female with coronary heart disease.

Influence of change in aerobic fitness and weight on prevalence of metabolic syndrome

Introduction

The metabolic syndrome is the clustering of several cardiometabolic risk factors that can lead to the development of coronary heart disease and type 2 diabetes. We evaluated whether a change in aerobic fitness resulting from a lifestyle intervention could significantly change the odds of metabolic syndrome prevalence.

Methods

Participants (n = 810) were recruited into PREMIER, a multicenter, randomized, controlled clinical trial with outcome assessments at 6 and 18 months. The primary eligibility criterion was a diagnosis of prehypertension or stage 1 hypertension. PREMIER randomized participants to 2 lifestyle interventions, both of which included increased physical activity, or an advice-only control group. Participants completed a submaximal treadmill exercise test; we used reduction in heart rate as the measure of improved aerobic fitness. We used logistic regression to determine intervention effects on metabolic syndrome prevalence. Our models controlled for dietary pattern change.

Results

The lifestyle interventions had no significant effect on metabolic syndrome prevalence at 6 months or 18 months. When combining intervention and control groups, at 6 and 18 months, a 1-beat-per-minute reduction in heart rate was associated with a 4% reduction in prevalence of metabolic syndrome (P < .001). When we tested for weight change as a mediator, the association was no longer significant.

Conclusion

Increased aerobic fitness may reduce prevalence of metabolic syndrome. This association appears to be mediated through concomitant weight change.

Long-term effects of smoking and smoking cessation on exercise stress testing: three-year outcomes from a randomized clinical trial

BACKGROUND

The long-term effects of smoking and smoking cessation on markers of cardiovascular disease (CVD) prognosis obtained during treadmill stress testing (TST) are unknown. The purpose of this study was to evaluate the long-term effects of smoking cessation and continued smoking on TST parameters that predict CVD risk.

METHODS

In a prospective, double-blind, randomized, placebo-controlled trial of 5 smoking cessation pharmacotherapies, symptom-limited TST was performed to determine peak METs, rate-pressure product (RPP), heart rate (HR) increase, HR reserve, and 60-second HR recovery, before and 3 years after the target smoking cessation date. Relationships between TST parameters and treatments among successful abstainers and continuing smokers were evaluated using multivariable analyses.

RESULTS

At baseline, the 600 current smokers (61% women) had a mean age of 43.4 (SD 11.5) years and smoked 20.7 (8.4) cigarettes per day. Their exercise capacity was 8.7 (2.3) METs, HR reserve was 86.6 (9.6)%, HR increase was 81.1 (20.9) beats/min, and HR recovery was 22.3 (11.3) beats. Cigarettes per day and pack-years were independently and inversely associated with baseline peak METs (P < .001), RPP (P < .01, pack-years only), HR increase (P < .05), and HR reserve (P < .01). After 3 years, 168 (28%) had quit smoking. Abstainers had greater improvements than continuing smokers (all P < .001) in RPP (2,055 mm Hg beats/min), HR increase (5.9 beats/min), and HR reserve (3.7%), even after statistical adjustment (all P < .001).

CONCLUSIONS

Smokers with a higher smoking burden have lower exercise capacity, lower HR reserve, and a blunted exercise HR response. After 3 years, TST improvements suggestive of improved CVD prognosis were observed among successful abstainers.

Variations in prevalent cardiovascular disease and future risk by metabolic syndrome classification in the REasons for Geographic and Racial Differences in Stroke (REGARDS) study

BACKGROUND

The International Diabetes Federation (IDF) and Adult Treatment Panel (ATP) III define metabolic syndrome (MetSyn) differently, with unclear implications for cardiovascular disease (CVD) risk.

METHODS

We examined 22,719 participants in the REGARDS study. We classified participants as: no MetSyn, MetSyn by ATP-III and IDF criteria, MetSyn by ATP-only, or MetSyn by IDF-only. To assess current CVD, we determined the odds of self-reported CVD by MetSyn category using multivariable logistic regression, controlling for socio-demographic and behavioral factors. To estimate future coronary heart disease risk, we calculated Framingham risk scores (FRS).

RESULTS

Overall, 10,785 individuals (47%) had MetSyn. Of these, 79% had MetSyn by both definitions, 6% by ATP-only, and 14% by IDF-only. Compared to those without MetSyn, ATP-only individuals had the highest odds of current CVD and of having a FRS >20%. Also compared to those without MetSyn, IDF-only individuals had 43% higher odds of current CVD and 2-fold increased odds of having a FRS >20%.

CONCLUSIONS

Consistent with previous reports, ATP-III MetSyn criteria identified individuals with increased odds of CVD and elevated future coronary heart disease risk. However, the IDF definition identified a clinically important number of additional individuals at excess CVD risk.

The relationship between body mass index and cardiopulmonary exercise testing in chronic systolic heart failure

BACKGROUND

Cardiopulmonary exercise testing (CPX) in patients with systolic heart failure (HF) is important for determining HF prognosis and helping guide timing of heart transplantation. Although approximately 20% to 30% of patients with HF are obese (body mass index [BMI] >30 kg/m(2)), the impact of BMI on CPX results is not well established. The objective of this study was to assess the relationship between BMI and CPX variables, including peak oxygen uptake (VO(2)) at ventilatory threshold, oxygen pulse, and ventilation-carbon dioxide production ratio.

METHODS

Consecutive patients with systolic HF (n = 2,324) enrolled in the Heart Failure and A Controlled Trial Investigating Outcomes of Exercise Training trial who had baseline BMI recorded were included in this study. Subjects were divided into strata based on BMI: underweight (BMI <18.5 kg/m(2)), normal weight (BMI 18.5-24.9 kg/m(2)), overweight (BMI 25.0-29.9 kg/m(2)), obese I (BMI 30-34.9 kg/m(2)), obese II (BMI 35-39.9 kg/m(2)), and obese III (BMI > or = 40 kg/m(2)).

RESULTS

Obese III, but not overweight; obese I; or obese II was associated with decreased peak VO(2) (mL kg(-1) min(-1)) compared to normal weight status. Increasing BMI category was inversely related to ventilation/carbon dioxide production (V(E)/V(CO2)) ratio (P < .0001). On multivariable analysis, BMI was a significant independent predictor of peak VO(2) (partial R(2) = 0.07, P < .0001) and V(E)/V(CO2) slope (partial R(2) = 0.03, P < .0001) in patients with chronic systolic HF.

CONCLUSIONS

Body mass index is significantly associated with key CPX fitness variables in patients with HF. The influence of BMI on the prognostic value of CPX in HF requires further evaluation in longitudinal studies.

Effects of cardiac rehabilitation in patients with metabolic syndrome after coronary artery bypass grafting

BACKGROUND

Cardiac rehabilitation (CR) has numerous beneficial effects, including the modification of coronary risk factors and improvement of the prognosis, in patients with coronary artery disease (CAD). Limited data are available regarding the effects of CR on the physical status and risk factors in patients with metabolic syndrome (MetS) after coronary artery bypass grafting (CABG).

METHODS AND RESULTS

We enrolled 32 patients with MetS after CABG, who participated in a supervised CR program for 6 months. Metabolic parameters, blood chemistry, exercise tolerance, and muscle strength of the thigh were measured before and after CR. After CR: (1) the body mass index, waist circumference, and fat weight significantly decreased; (2) peak V O(2) and anaerobic threshold were significantly increased; (3) isokinetic peak torques of knee extensor and flexor muscles significantly increased; (4) metabolic scoring defined by the number of the modified Adult Treatment Panel criteria of the US National Cholesterol Education Program was significantly improved; (5) serum concentration of high-sensitivity C-reactive protein also significantly decreased.

CONCLUSIONS

These results suggest that CR might be useful for patients with MetS after CABG.

Left ventricular function and exercise capacity

CONTEXT

Limited information exists regarding the role of left ventricular function in predicting exercise capacity and impact on age- and sex-related differences.

OBJECTIVES

To determine the impact of measures of cardiac function assessed by echocardiography on exercise capacity and to determine if these associations are modified by sex or advancing age.

DESIGN

Cross-sectional study of patients undergoing exercise echocardiography with routine measurements of left ventricular systolic and diastolic function by 2-dimensional and Doppler techniques. Analyses were conducted to determine the strongest correlates of exercise capacity and the age and sex interactions of these variables with exercise capacity.

SETTING

Large tertiary referral center in Rochester, Minnesota, in 2006.

PARTICIPANTS

Patients undergoing exercise echocardiography using the Bruce protocol (N = 2867). Patients with echocardiographic evidence of exercise-induced ischemia, ejection fractions lower than 50%, or significant valvular heart disease were excluded.

MAIN OUTCOME MEASURE

Exercise capacity in metabolic equivalents (METs).

RESULTS

Diastolic dysfunction was strongly and inversely associated with exercise capacity. Compared with normal function, after multivariate adjustment, those with moderate/severe resting diastolic dysfunction (-1.30 METs; 95% confidence interval [CI], -1.52 to -0.99; P < .001) and mild resting diastolic dysfunction (-0.70 METs; 95% CI, -0.88 to -0.46; P < .001) had substantially lower exercise capacity. Variation of left ventricular systolic function within the normal range was not associated with exercise capacity. Left ventricular filling pressures measured by resting E/e' of 15 or greater (-0.41 METs; 95% CI, -0.70 to -0.11; P = .007) or postexercise E/e' of 15 or greater (-0.41 METs; 95% CI, -0.71 to -0.11; P = .007) were similarly associated with a reduction in exercise capacity, each in separate multivariate analyses. Individuals with impaired relaxation (mild dysfunction) or resting E/e' of 15 or greater had a progressive increase in the magnitude of reduction in exercise capacity with advancing age (P < .001 and P = .02, respectively). Other independent correlates of exercise capacity were age (unstandardized beta coefficient, -0.85 METs; 95% CI, -0.92 to -0.77, per 10-year increment; P < .001), female sex (-1.98 METs; 95% CI, -2.15 to -1.84; P < .001), and body mass index greater than 30 (-1.24 METs; 95% CI, -1.41 to -1.10; P < .001).

CONCLUSION

In this large cross-sectional study of those referred for exercise echocardiography and not limited by ischemia, abnormalities of left ventricular diastolic function were independently associated with exercise capacity.

Drugs are not enough: the metabolic syndrome--a call for intensive therapeutic lifestyle change

Whether intensive pharmacologic cardiovascular risk factor management reduces metabolic syndrome (MetS) prevalence is unknown. The authors compared the number of secondary prevention medications and National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III)-defined MetS prevalence in coronary artery disease patients entering cardiac rehabilitation from 1996 to 2001 (period 1, n=516) with those entering from 2002 to 2006 (period 2, n=609). Age, sex, and ethnicity were similar in both periods. From period 1 to period 2, participants took more secondary prevention medications (2.8+/-1.3 vs 3.5+/-1.0, P<.001). Prevalence of low high-density lipoprotein cholesterol (66% vs 66%), diabetes (37% vs 38%), and hypertension (81% vs 81%) were unchanged. The prevalence of hypertriglyceridemia decreased (48% vs 36%, P<.001), but the proportion meeting criteria for elevated waist circumference increased (51% vs 58%, P<.05), resulting in no change in overall MetS prevalence (60% vs 59%, P=NS). More emphasis on therapeutic lifestyle change in addition to intensive pharmacologic therapy is needed to reduce MetS prevalence in patients with coronary artery disease.

Adverse baseline physiological and psychosocial profiles of women enrolled in a cardiac rehabilitation clinical trial

PURPOSE

Coronary heart disease (CHD) remains the leading cause of death in women. Despite positive outcomes associated with cardiac rehabilitation (CR), investigations of women are sparse. This article presents the baseline physiological and psychosocial profiles of 182 women in the Women's-Only Cardiac Rehabilitation study.

METHOD

Women were randomized to a women's-only motivational interviewing or traditional CR group. Physiological measures included lipid profiles, body mass index, functional capacity, and anthropomorphic measures. Psychosocial measures included optimism, hope, social support, anxiety, depression, quality of life, and health perceptions. The median age was used to split the sample to examine data on 92 younger (< or = 64 years) and 90 older (>64 years) women.

RESULTS

With a mean age of 63 years, 66.5% were white, 47% were retired, and 54% were married. Most women were physically inactive (83%), hypertensive (76%), and overweight (56%). Most women (71.4%) met the criteria for metabolic syndrome. Younger women demonstrated significantly worse psychosocial profiles than older women. More of the younger women (64%) had depressive symptoms than older women (37%). Younger women demonstrated a mean Center for Epidemiological Studies Depression Scale score of 20.8 +/- 12.4, whereas older women had a substantially lower mean score of 14.9 +/- 9.5 (P < .001). Younger participants also reported significantly more anxiety than older participants (38.8 +/- 13.4 vs 32.8 +/- 10.6, P < .001).

CONCLUSION

Younger women enrolled in a CR clinical trial had adverse baseline risk factor profiles placing them at high risk for disease progression.

The visfatin gene is associated with glucose and lipid metabolism in a Chinese population

AIMS

Visfatin is a newly discovered adipokine found in abundance in visceral fat. It lowers plasma glucose in humans and mice. In this study, we explored the relationships between the plasma level of visfatin and genetic single nucleotide polymorphisms (SNPs) and Type 2 diabetes mellitus (T2DM) and anthropometric and metabolic parameters in Chinese subjects.

METHODS

Oral glucose tolerance tests (OGTT) and biochemical assays for plasma insulin, lipid profiles and serum visfatin were performed in 241 newly diagnosed T2DM patients, subjects with impaired glucose regulation (IGR), and normal glucose tolerant subjects more than 40 years of age. Genotyping for three SNP loci: -1535C/T, rs2058539 and rs10953502 were performed using the allele-specific real-time PCR method.

RESULTS

Visfatin levels were similar in T2DM patients, IGR and normal glucose tolerant subjects. However, visfatin levels were significantly lower in obese than normal-weight subjects (13.66 +/- 0.87 vs. 15.46 +/- 0.47 ng/ml, P = 0.03). There was suggestively significant correlation between visfatin level and body mass index (r = -0.17 P = 0.07) and waist-hip ratio (r = 0.16 P = 0.08) in male subjects, but not in female subjects. Allele and common haplotype frequencies of the three SNP loci were similar in T2DM patients, IGR and normal glucose tolerant subjects. However, significant associations were found between these three SNP loci and plasma glucose concentration at 0 and 120 min during OGTT, the area under the response curve for plasma glucose, and triglyceride and total cholesterol levels.

CONCLUSIONS

Serum visfatin levels may be related to visceral obesity in men, and the visfatin gene may account for variation of glucose and lipid parameters in Chinese subjects.

The obesity epidemic in the United States: role of cardiac rehabilitation

Obesity is an independent risk factor for the development of coronary heart disease. The vast majority of individuals entering into cardiac rehabilitation are overweight. Weight loss has been shown to be helpful in modifying multiple coronary risk factors. Cardiac rehabilitation programs, as secondary prevention centers, need to develop programs to assist participants with meaningful and permanent weight loss.

A simple tool to predict exercise capacity of obese patients with ischaemic heart disease

OBJECTIVE

To define an equation that predicts exercise capacity taking into account body mass index (BMI).

DESIGN

Retrospective analysis and validation study of a multidisciplinary programme aimed at weight loss and physical rehabilitation.

SETTING

Tertiary referral hospital.

PATIENTS AND METHODS

372 consecutive obese participants (249 men) with stable ischaemic heart disease, aged mean 60.1 (SD 8.7) years, underwent a treadmill exercise test. BMI was 37.8 (4.5) kg/m(2). In the validation study the model was tested in 87 patients with similar characteristics.

RESULTS

Mean exercise intensity was 6.6 (SD 2.4) metabolic equivalents (METs). Multivariate linear regression analysis defined two simple models that considered exercise intensity as the dependent variable and a set of independent variables such as anthropometric measures, age and sex in the first one, plus associated clinical conditions and drug treatment in the second one. The correlation coefficients of the two models were R = 0.630 and R = 0.677, respectively. Age, BMI and sex were the strongest predictors of exercise capacity. The first derived equation efficiently predicted exercise capacity: in the validation study predicted exercise intensity was 6.3 (1.6) METs and attained exercise intensity was 6.3 (2.4) METs (p = 0.903) with a highly significant correlation (R = 0.534, p < 0.001).

CONCLUSION

BMI is an important determinant of exercise capacity of obese people with ischaemic heart disease. The use of a simple equation may help in predicting exercise capacity, in individualising exercise protocol and in setting up rehabilitation programs for obese patients.

Two major QTLs and several others relate to factors of metabolic syndrome in the family blood pressure program

Genome-wide variance components linkage analysis was performed on 4 latent factors underlying metabolic syndrome derived from 10 risk factors. The latent factors represent obesity and insulin, blood pressure, lipids and insulin, and central obesity. The metabolic syndrome factor scores were derived in 4 ethnic groups recruited in 3 Networks of the Family Blood Pressure Program: GENOA (blacks, Hispanics, and whites), HyperGEN (blacks and whites), SAPPHIRe (Asians). Heritabilities of metabolic syndrome factors ranged from 66% for obesity and insulin to 11% for blood pressure factor. We observed higher heritabilities for obesity and insulin, and lipids and insulin, whereas those for blood pressure and central obesity were smaller. Linkage analysis detected two major quantitative trait loci. One of them linked to the obesity and insulin factor with a lod score of 3.94 (P=0.00001, marker GATA11A06, D18S53, 41.24 cM) at marker positions linkage (lod 4.71, at 46.84 cM at 1-cM-apart distances linkage), located on chromosome 18p11.21 in GENOA black. The other linked to the blood pressure factor with a lod score of 3.22 (P=0.000059, marker GATA49C09, D17S1290, 82 cM) at marker positions linkage (lod 3.56, at 84.63 cM for 1 cM apart distances linkage) located on chromosome 17q23.1 in Hispanics. These quantitative trait loci, together with 4 additional ones with lod scores >2.5, and 30 additional ones with lod score >1.7, offer hope for dissecting the genetic architecture of metabolic syndrome with beneficial implications for molecular diagnosis, prognosis, and in potential medical intervention.