Why primary obesity is a disease?

Obesity must be considered a real pathology. In the world wide, obesity represent one of the major public health issue associated with increased morbidity and mortality. Overweight or obesity, in fact, significantly increases the risk of contracting diseases, such as: arterial hypertension, dyslipidemia, type 2 diabetes mellitus, coronary heart disease, cerebral vasculopathy, gallbladder lithiasis, arthropathy, ovarian polycytosis, sleep apnea syndrome, and some neoplasms. Despite numerous informative campaigns, unfortunately, the fight against obesity does not seem to work: in the last years, the prevalence continued to increase. The progressive and rapid increase in the incidence of obesity, which has characterized most of the economically advanced countries in the last decade, has been the main stimulus for the research of the mechanisms underlying this pathology and the related disorders. The aims of this review is to provide a revision of the literature in order to define obesity as diseases, secondly to highlight the limits and the inaccuracy of common tools used for the diagnosis of obesity, and as a third thing to strengthen the concept of the complexity of obesity as a disease among political health care providers. Obesity may be viewed as a multifactorial pathology and chronic low-grade inflammatory disease. In fact, people affected by obesity have greater risk of developing comorbility and morbility, respect to healthy. Hence, the absolute therapeutic benefit is directly proportional to the basic risk. So, internationally interest on early diagnosis of obesity is growing to avoid under- and overdiagnosis consequences. Therefore, the consequences are an aggravation of the disease and an increase in obesity related pathology like diabetes, cardiovascular disease, and cancer. The most widely used parameter for diagnosis, body mass index (BMI) is not suitable for assessing the body fat. In fact, several studies demonstrate that BMI alone cannot define obesity, which consists not so much in weight gain as in excess fat mass. The use of suitable tools for the assessment of fat mass percentage combined with clinical and genetic analysis allowed to identify different phenotypes of obesity, which explain the various paradoxes of obesity. It is essential to adopt all possible strategies to be able to combat obesity, ameliorate the suffering of patients, and reduce the social and treatment costs of obesity.

Obesity, Cardiac Remodeling, and Metabolic Profile: Validation of a New Simple Index beyond Body Mass Index

Aim:

The body mass index (BMI), the most used anthropometric index of obesity, has an important limitation, not taking into consideration the distribution of body fat. We developed a new simple index: the waist-corrected BMI (wBMI), calculated as waist circumference (WC) × BMI. The study aim was to assess the role of wBMI, compared to BMI, WC, and Waist-to-Height Ratio (WHtR) in predicting abnormal cardiac geometry, insulin resistance, increased arterial stiffness, and dyslipidemia.

Methods:

This was a cross-sectional study that included 805 patients referred to our Department of Preventive Cardiology for risk factors evaluation and treatment. Eleven echographic and laboratory parameters were determined, and receiver operating characteristic (ROC) curves were derived. Areas under ROC curves (AUC) were used to assess the accuracy of the four indexes to identify unfavorable characteristics.

Results:

There were 29% overweight, 59% obese, and 77% hypertensive patients. Of 11 echographic and laboratory parameters, wBMI, BMI, WHtR, and WC had the largest AUC for identifying 3, 1, 6, and 1 parameters, respectively, but with overlapping 95% confidence intervals. wBMI had the largest AUC for increased arterial stiffness and insulin resistance; also, it was superior to BMI for increased left atrial volume, relative wall thickness, and triglyceride level.

Conclusions:

In a large population with a high prevalence of obesity and hypertension, all four indexes were associated with unfavorable characteristics. wBMI has the theoretical advantage of taking into account simultaneously the global fat mass and distribution and might be useful for a better cardiovascular risk assessment.

The effect of laparoscopic sleeve gastrectomy (LSG) on glycemic control in morbidly obese patients

INTRODUCTION

Bariatric procedures have become popular in treating not only the morbid obesity but also the metabolic derangements. Sleeve Gastrectomy has recently become popular as a standalone procedure and its usefulness as a metabolic procedure especially glycemic control is still under investigation. One of the most commonly used measure of insulin resistance is statistically derived 'Homeostatic model assessment of insulin resistance (HOMA-IR).

AIM

The effect of Laparoscopic Sleeve Gastrectomy (LSG) on clinical and measurable change in glycemic control as seen by reduction of insulin resistance ie HOMA-IR levels in morbidly obese patients.

MATERIAL AND METHODS

All the patients with BMI ≥35 kg/m(2) with co morbidities and BMI ≥40 kg/m(2) even without co morbidities were included in the study. The period of the study was from Feb 2013 to Sep 2014. Fasting (FBS), post prandial blood sugar (PPBS) and Insulin levels were checked before the surgery, 1month and 3 month after the surgery. We also recorded BMI and diabetic status. HOMA-IR was calculated and trends were recorded.

STATISTICAL ANALYSIS

Statistical analysis was carried out using SPSS 16.0.

RESULTS

Out of 28 patients 8 were males and 20 were females. The mean age was 43 yrs. 11 (39%) patients were diabetic and mean BMI was 44 kg/m(2) and a range of (35-61.3) kg/m(2). 11 patients had BMI > 45 kg/m(2). The HOMA-IR values decreased significantly after the surgery both in diabetics and non diabetics.

CONCLUSION

LSG results in improvement in glycemic control in both diabetics and non diabetics.

Prevalence and Prognostic Impact of Metabolic Syndrome in Asymptomatic (Stage A and B Heart Failure) Patients

BACKGROUND

Metabolic syndrome (MS) has an increased risk of cardiovascular events. Its relationship with asymptomatic left ventricular dysfunction (LVD) and prognosis has not been completely clarified.

OBJECTIVES

To determine, in asymptomatic patients (Stage A, B heart failure, HF), whether MS is associated with left ventricular systolic dysfunction (LVSD) and left ventricular diastolic dysfunction and its predictive role for cardiovascular events.

MATERIALS AND METHODS

We included 1920 nonconsecutive patients without symptoms of HF, with at least one cardiovascular risk factor, undergoing echocardiographic evaluation as preventive screening. We subdivided the study population according to the presence (Group 1) or absence (Group 2) of MS. The primary endpoint was a composite of cardiac death, myocardial infarction, coronary artery revascularization, stroke, and acute pulmonary edema. Secondary endpoints were hospitalization for HF and HF progression.

RESULTS

Overall prevalence of MS was 13.4% (n = 262, Group 1). In Group 2 (n = 1658), the prevalence of LVSD was 12.2%, while the prevalence of LVSD was 21.8% in Group 1 (relative risk [RR] 2.01; 95% confidence interval 1.4-2.8; P < 0.001). Adjusting for age and gender, MS resulted an independent predictor of LVSD (P < 0.001). After a median follow-up of 22 months, Group 1 patients had a significantly higher incidence of primary events (P < 0.001), including cardiac death (P = 0.04), and secondary events (P < 0.001). Both primary and secondary endpoints were more frequent in patients with LVSD (P < 0.001). In multivariate survival analysis, MS (but not its specific components) and LVSD were independently associated both with primary and secondary events (P ≤ 0.003). Incremental chi-square analysis showed the presence of combined LVD added to MS, and age raised significantly the predictive value of the model for the primary endpoint (Incremental chi-square = 8.6).

CONCLUSIONS

In stage A and B HF subjects, the coexistence of MS with functional or structural cardiac abnormalities, detected by echocardiography, showed a significant incremental value in predicting clinical cardiovascular events.

Increased left atrial size in obese children and its association with insulin resistance: a pilot study

Subclinical cardiac abnormalities represent predisposing factors for cardiovascular disease (CVD) in obese subjects. The aim of this study was to evaluate early cardiac abnormalities in obese youth and the potential association with insulin resistance (IR). Thirty obese (12 males (M)/18 females (F); age = 11.5 ± 2.4 years; body mass index (BMI)-standard deviation score (SDS) = +2.1 ± 0.5) and 15 normal weight (10 M/5 F; age = 12.8 ± 3.1 years; BMI-SDS = +0.3 ± 0.9) children and adolescents underwent Doppler two-dimensional echocardiographic assessments of left atrial (LA) and ventricular (LV) geometry and LV diastolic function (peak early [E] and late waves, E wave deceleration time, myocardial flow velocities). Homeostasis model assessment of IR (HOMA-IR) was used as an IR index. LA size was increased in obese children, as indicated by higher LA diameter (4.9 ± 0.5 vs 4.1 ± 0.4 cm, p < 0.001), area (14.3 ± 2.5 vs 10.7 ± 2.0 cm(2), p < 0.001), and volume (33.8 ± 10.6 vs 23.7 ± 6.4 ml, p = 0.003). LV mass was also increased in obese children (87.0 ± 16.6 vs 68.8 ± 13.2 g, p = 0.003), who also showed subtle diastolic dysfunctions, as indicated by higher values of E (97.1 ± 14.3 vs 86.2 ± 11.9 cm/s, p = 0.02). All the above parameters were significantly associated with BMI-SDS (p < 0.05). In addition, HOMA-IR was independently associated with LA diameter, area, and volume (β = 0.314, p = 0.040; β = 0.415, p = 0.008; β = 0.535, p = 0.001).

CONCLUSION

Obese children feature increased LA size, which emerged to be mainly correlated to, and possibly driven by IR, suggesting an increased CVD risk.

WHAT IS KNOWN

Left atrial and ventricular alterations have been reported in obese adults, and they represent predisposing factors for cardiovascular disease. There is some evidence suggesting that obese children show increased left ventricular mass and also increased atrial size, although with conflicting results.

WHAT IS NEW

Obese normotensive children showed a moderately increased atrial size, subtle alterations in left cardiac diastolic function, and ventricular mass. An association between insulin resistance and left cardiac changes was found, although its mechanism remains to be determined.

Galectin-3 Participates in Cardiovascular Remodeling Associated With Obesity

Remodeling, diastolic dysfunction, and arterial stiffness are some of the alterations through which obesity affects the cardiovascular system. Fibrosis and inflammation are important mechanisms underlying cardiovascular remodeling, although the precise promoters involved in these processes are still unclear. Galectin-3 (Gal-3) induces inflammation and fibrosis in the cardiovascular system. We have investigated the potential role of Gal-3 in cardiac damage in morbidly obese patients, and we have evaluated the protective effect of the Gal-3 inhibition in the occurrence of cardiovascular fibrosis and inflammation in an experimental model of obesity. Morbid obesity is associated with alterations in cardiac remodeling, mainly left ventricular hypertrophy and diastolic dysfunction. Obesity and hypertension are the main determinants of left ventricular hypertrophy. Insulin resistance, left ventricular hypertrophy, and circulating levels of C-reactive protein and Gal-3 are associated with a worsening of diastolic function in morbidly obese patients. Obesity upregulates Gal-3 production in the cardiovascular system in a normotensive animal model of diet-induced obesity by feeding for 6 weeks a high-fat diet (33.5% fat). Gal-3 inhibition with modified citrus pectin (100 mg/kg per day) reduced cardiovascular levels of Gal-3, total collagen, collagen I, transforming and connective growth factors, osteopontin, and monocyte chemoattractant protein-1 in the heart and aorta of obese animals without changes in body weight or blood pressure. In morbidly obese patients, Gal-3 levels are associated with diastolic dysfunction. In obese animals, Gal-3 blockade decreases cardiovascular fibrosis and inflammation. These data suggest that Gal-3 could be a novel therapeutic target in cardiac fibrosis and inflammation associated with obesity.

Left Ventricular Hypertrophy and Asymptomatic Cardiac Function Impairment in Chinese Patients with Simple Obesity using Echocardiography

BACKGROUND

Simple obesity in China is rising rapidly and causing increasing concern. The objectives of our study are to investigate cardiac structure and function in individuals with simple obesity and to analyze the effect of BMI on left ventricular structure and function.

METHODS

Between January 2012 and July 2014, echocardiography was performed in 361 consecutive patients visiting the outpatient echocardiography center for a health examination or cardiac evaluation before a weight loss operation in our hospital. Echocardiographic indices, waist-to-hip ratios, BMI, and metabolic markers were evaluated. We analyzed these data using Student's t test (normally distributed) or a nonparametric test (not normally distributed) for continuous variables and chi-square test for categorical variables. Multivariate correlation and regression analysis were conducted for comparisons.

RESULTS

The study sample was divided into three groups: a normal/overweight group (BMI < 28.0 kg/m(2)), a mildly/moderately obese group (BMI 28-39.9 kg/m(2)), and a severely obese group (BMI ≥ 40 kg/m(2)). There were no significant differences in clinical and laboratory characteristics among the groups, except for BMI and waist-to-hip ratio. The severely obese group had a higher left ventricular end diastolic diameter (LVEDD; p < 0.01) and lower left ventricular ejection fraction (LVEF; p < 0.01) than the mildly/moderately obese group, which had a higher LVEDD and LV mass index (LVMI) than the normal/overweight group. BMI correlated well with LVEDD, left ventricular posterior wall thickness at end-diastole (LVPW), LV mass, LVMI, and E/e'. In addition, age was significantly associated with some echocardiographic parameters, including left atrial dimension (r = 0.366, p < 0.01), LVPW (r = 0.347, p < 0.01), interventricular septal thickness at end- diastole (r = 0.351, p< 0.01), and E/A (r = -0.47, p < 0.01).

CONCLUSIONS

Simple obesity caused cardiac structural changes, including LV hypertrophy and LV enlargement, and severe obesity resulted in asymptomatic LV systolic and diastolic function impairment.

Role of Cardiovascular Ultrasound in the Evaluation of Obese Subjects

Obesity represents a worldwide increasing health problem. Obesity, through complex and not fully understood pathogenetic mechanisms, induces different structural and functional changes of left heart chambers, right heart chambers, and arteries. Ultrasound techniques are the first choice for a comprehensive assessment of the cardiovascular adaptation to obesity. This review summarizes the up-to-date literature on the topic, with particular focus on the main clinical studies, which range over different cardiovascular adaptations to obesity, namely left ventricular mass, diastolic function, right ventricle structure and function, arterial stiffness, and intima-media thickness. Also, the importance of epicardial fat and of the degree of obesity is described. Finally, the role of weight loss and bariatric surgery and the study of cardiovascular obesity-induced abnormalities in children and adolescent are discussed.

The role of echocardiography in the evaluation of cardiac damage in hypertensive obese patient

Obesity rates are rising worldwide. Often obesity is associated with hypertension leading to an increased cardiovascular risk. Both obesity and hypertension induce several modifications in cardiac structure and function, particularly atrial and ventricular remodeling is a common finding shared by these two conditions. It has been demonstrated obesity leads to: left ventricular (LV) mass increase, LV systolic and diastolic dysfunction, left atrium (LA) size increase, LA function alterations and pericardial fat accumulation. Nowadays, the development of cardiac imaging techniques allows to early identifying any preclinical damage related to hypertension and obesity. This could be very important in order to improve patient management and medical therapy.

Asymptomatic Left Ventricular Dysfunction and Metabolic Syndrome: Results from an Italian Multicenter Study

Context:

Metabolic syndrome (MS) is a cluster of interrelated common clinical disorders, including obesity, insulin resistance, glucose intolerance, hypertension and dyslipidemia, associated with a greater risk of atherosclerotic cardiovascular disease than any of its individual components. Although MS is associated with increased cardiovascular risk (CVR), its relationship with heart failure (HF) and left ventricular (LV) dysfunction is not fully understood.

Aims:

We sought to determine whether MS is associated to LV systolic and diastolic dysfunction in a sample of patients with MS and no symptoms for HF.

Subjects and Methods:

We enrolled 6422 consecutive asymptomatic patients admitted to echo-lab for a routine echocardiogram. We calculated LV systolic and diastolic function, by Simpson biplane method and validated Doppler parameters, respectively. MS was diagnosed if three or more CVR factors were found.

Results:

LV systolic function was evaluated in 6175 patients (96.2%). In the group of patients without MS (n = 5630), the prevalence of systolic dysfunction was 10.8% (n = 607) while in the group of patients with MS (n = 545) it was 12.5% (n = 87), (RR1.57; CI 95% 1.2-2.0; P < 0.001). Diastolic function was evaluated in 3936 patients (61.3%). In the group of patients without MS (n = 3566) the prevalence of diastolic dysfunction was 33.3% (n = 1187), while in patients with MS (n = 370) it was 45.7% (n = 169), (RR1.68; CI95% 1.3-2.0; P < 0.001). After adjustment for age and gender, MS proved to be an independent predictor of LV systolic and diastolic dysfunction.

Conclusions:

Our data show that asymptomatic LV systolic and diastolic dysfunction, is correlated with MS and demonstrate that echocardiography is a useful tool to detect patients at high risk for HF. Echocardiography in asymptomatic patients with MS may lead to a therapy initiation at early stages to prevent future cardiovascular events and HF.