Index of central obesity as a parameter to replace waist circumference for the definition of metabolic syndrome in predicting cardiovascular disease

Determinants of Arterial Stiffness in Patients with Morbid Obesity. The Role of Echocardiography and Carotid Ultrasound Imaging

Background and objective: Morbid obesity is accompanied by an increased cardiovascular (CV) risk, which justifies a multidisciplinary, integrative approach. Arterial stiffness has a well-defined additional role in refining individual CV risk. Given that echocardiography and carotid ultrasound are usual methods for CV risk characterization, we aimed to identify the imaging parameters with a predictive value for early-onset arterial stiffness. Material and methods: We conducted a study in which 50 patients (divided into two equal groups with morbid obesity and without obesity), age and gender matched, untreated for cardiovascular risk factors, were addressed to bariatric surgery or non-inflammatory benign pathology surgery. Before the surgical procedures, we evaluated demographics, anthropometric data and biochemical parameters including adipokines (chemerin, adiponectin). Arterial stiffness was evaluated using the Medexpert ArteriographTM TL2 device. Transthoracic echocardiography and carotid ultrasound were also performed. We also analyzed adipocyte size and vascular wall thickness in intraoperative biopsies. Results: Left ventricle (LV) mass index (p = 0.2851), LV ejection fraction (LVEF) (p = 0.0073), epicardial adipose tissue thickness (p = 0.0001) as echocardiographic parameters and carotid intima–media thickness (p = 0.0033), relative wall thickness (p = 0.0295), wall to lumen thickness ratio (p = 0.0930) and carotid cross-sectional area (p = 0.0042) as ultrasound parameters were significant measures in our groups and were assessed in relation to adipocyte size, blood vessel wall thickness and adipokines serum levels. Statistical analysis revealed directly proportional relationships between LV mass index (p = 0.008), carotid systolic thickness of the media (p = 0.009), diastolic thickness of the media (p = 0.007), cross-sectional area (p = 0.001) and blood vessel wall thickness. Carotid relative wall thickness positively correlates with adipocyte size (p = 0.023). In patients with morbid obesity, chemerin and adiponectin/chemerin ratio positively correlates with carotid intima–media thickness (p = 0.050), systolic thickness of the media (p = 0.015) and diastolic thickness of the media (p = 0.001). The multiple linear regression models revealed the role of epicardial adipose tissue thickness and carotid cross-sectional area in predicting adipocyte size which in turn is an independent factor for arterial stiffness parameters such as pulse wave velocity, subendocardial viability ratio and aortic augmentation index. Conclusions: Our results suggest that epicardial adipose tissue thickness, carotid intima–media thickness, relative wall thickness and carotid cross-sectional area might be useful imaging parameters for early prediction of arterial stiffness in patients with morbid obesity.

The Influence of Metabolic Syndrome on the Risk of Hepatocellular Carcinoma in Patients with Chronic Hepatitis B Infection in Mainland China

BACKGROUND

The association between metabolic syndrome (MS), both in terms of its components and as a whole, and the risk of hepatocellular carcinoma (HCC) in subjects with hepatitis B virus (HBV) infection remains unclear, especially in mainland China.

METHODS

We prospectively included 6,564 individuals with HBV infection from an initial cohort of 105,397 civil servants. The multivariate-adjusted HR and 95% confidence interval (95% CI) were evaluated using Cox proportional hazards models to explore the potential connection between HCC risk and MS. Cumulative incidences were plotted using Kaplan-Meier curves.

RESULTS

After a 45,668.0 person-year follow-up (76.0 ± 30.8 months) of 6,564 subjects who were seropositive for hepatitis B surface antigen, 89 incident HCC cases were identified. MS as a whole was independently associated with a 2-fold increased HCC risk (HR, 2.25; 95% CI, 1.41-3.60) after adjusting for age (in 1-year increments), gender, cigarette smoking, alcohol consumption, liver cirrhosis, and elevated aspartate aminotransferase levels (≥40 U/L). Subjects with three or more factors and those with one or two factors had adjusted increased HCC risks of 2.12-fold (95% CI, 1.16-3.89) and 1.28-fold (95% CI, 0.74-2.22), respectively, in comparison with those without any metabolic factors. Central obesity and type 2 diabetes were associated with significantly increased HCC risk, whereas this association was not observed in obese subjects (body mass index ≥30 kg/m²; 95% CI, 0.73-3.44).

CONCLUSIONS

MS as a whole, central obesity, and type 2 diabetes were independently associated with increased HCC risk in a population with HBV infection in mainland China.

IMPACT

MS may be a risk factor for HCC.

Empagliflozin reduces body weight and indices of adipose distribution in patients with type 2 diabetes mellitus

AIMS

To determine the effects of empagliflozin on adiposity indices among patients with type 2 diabetes mellitus.

METHODS

Changes in weight, waist circumference, estimated total body fat, index of central obesity and visceral adiposity index were assessed using analysis of covariance and testing of treatment by strata for age, sex and baseline waist circumference in patients with type 2 diabetes mellitus randomized to blinded treatment with empagliflozin versus placebo in clinical trials of 12 weeks (cohort 1) or 24 weeks (cohort 2) duration.

RESULTS

This study comprised 3300 patients (cohort 1, N = 823; cohort 2, N = 2477). Empagliflozin reduced weight, waist circumference and adiposity indices versus placebo in both cohorts. Adjusted mean (95% confidence interval) change from baseline in empagliflozin versus placebo was -1.7 kg (-2.1 to -1.4 kg) and -1.9 kg (-2.1 to -1.7 kg) for body weight (p < 0.001); -1.3 cm (-1.8 to -0.7 cm) and -1.3 cm (-1.7 to -1.0 cm) for waist circumference (p < 0.001); -0.2% (-0.7% to 0.3%; p = 0.45) and -0.3% (-0.7% to 0.0%; p = 0.08) for estimated total body fat; -0.007 (-0.011 to -0.004) and -0.008 (-0.010 to -0.006) for index of central obesity (p < 0.001); and -0.3 (-0.5 to 0.0; p = 0.07) and -0.4 (-0.7 to -0.1; p = 0.003) for visceral adiposity index in cohorts 1 and 2, respectively. Adipose reductions were seen across most age, sex and waist circumference subgroups.

CONCLUSION

Empagliflozin significantly reduced weight and adiposity indices with the potential to improve cardiometabolic risk among patients with type 2 diabetes mellitus.

Comparison of Adipose Distribution Indices with Gold Standard Body Composition Assessments in the EMPA-REG H2H SU Trial: A Body Composition Sub-Study

INTRODUCTION

Excess adiposity contributes to cardiometabolic disease. Although adipose depots can be measured using imaging, implementation remains limited in practice. Data comparing surrogate indices of total and visceral adiposity with gold standard measurements in the context of a clinical trial population are lacking. We explored the relationships between adipose distribution indices and imaging assessments of body composition using baseline data from the EMPA-REG H2H SU™ trial.

METHODS

118 participants from the Phase III trial of empagliflozin 25 mg vs. glimepiride 1-4 mg enrolled in a dedicated sub-study underwent assessment of total fat and fat-free mass by dual x-ray absorptiometry (n = 93) and abdominal visceral (VAT) and subcutaneous adipose tissue by magnetic resonance imaging (n = 99). Correlations with waist circumference (WC), estimated total body fat (eTBF), index of central obesity (ICO), and visceral adiposity index (VAI) were assessed.

RESULTS

eTBF was highly representative of total body fat (Spearman's ρ = 0.73, P < 0.001) but not associated with VAT. WC and ICO were strongly, and VAI to a lesser degree, correlated with VAT (ρ = 0.66, P < 0.001; ρ = 0.52, P < 0.001; ρ = 0.24, P = 0.02, respectively).

CONCLUSION

These findings support the use of eTBF and WC or ICO as surrogate indices for total body fat and VAT, respectively, in the absence of gold standard imaging methodology.

Severity of non-alcoholic fatty liver disease is associated with high systemic levels of tumor necrosis factor alpha and low serum interleukin 10 in morbidly obese patients

Morbid obesity has been shown to increase the risk to develop hepatic steatosis, also referred to as non-alcoholic fatty liver disease (NAFLD). Emerging evidence suggests that the severity of NAFLD may associate with increased serum levels of inflammatory markers as well as decreased concentration of mediators with anti-inflammatory actions, such as tumor necrosis factor alpha (TNF-α) and interleukin (IL) 10, respectively. We thus examined the serum levels of TNF-α and IL-10 in 102 morbidly obese women and men (body mass index > 40 kg/m(2)), exhibiting different grades of NAFLD. Blood glucose, glycated hemoglobin, insulin, the homeostatic model assessment of insulin resistance (HOMA-IR), total cholesterol, triglycerides, high- and low-density lipoproteins, parameters of liver function, TNF-α, and IL-10 were measured in each subject. The stage of NAFLD was estimated by abdominal ultrasound imaging. In comparison with morbidly obese subjects without steatosis, morbidly obese patients with NAFLD showed increased age (39.23 ± 9.80 years), HOMA-IR (6.74 ± 1.62), total cholesterol (219.7 ± 9.58 mg/dl), aspartate aminotransferase (36.25 ± 3.24 UI/l), gamma-glutamyl transpeptidase (37.12 ± 3.41 UI/l), and TNF-α (37.41 ± 1.72 pg/ml) as well as decreased serum levels of IL-10 (61.05 ± 2.43 pg/ml). Interestingly, the systemic levels of TNF-α increased, while IL-10 decreased in accordance with the severity of NAFLD, which supports a role for systemic inflammatory mediators in promoting steatosis progression. Further clinical prospective studies need to be addressed to elucidate the role of TNF-α and IL-10 in the development of NAFLD while also establishing their clinical utility in the assessment of morbidly obese patients at higher risk to develop severe steatosis.

SGLT-2 inhibitors and cardiovascular risk: proposed pathways and review of ongoing outcome trials

Given the multi-faceted pathogenesis of atherosclerosis in type 2 diabetes mellitus (T2DM), it is likely that interventions to mitigate this risk must address cardiovascular (CV) risk factors beyond glucose itself. Sodium glucose cotransporter-2 (SGLT-2) inhibitors are newer antihyperglycaemic agents with apparent multiple effects. Inherent in their mode of action to decrease glucose reabsorption by the kidneys by increasing urinary glucose excretion, these agents improve glycaemic control independent of insulin secretion with a low risk of hypoglycaemia. In this review, we outline those CV risk factors that this class appears to influence and provide the design features and trial characteristics of six ongoing outcome trials involving more than 41,000 individuals with T2DM. Those risk factors beyond glucose that can potentially be modulated positively with SGLT-2 inhibitors include blood pressure, weight, visceral adiposity, hyperinsulinaemia, arterial stiffness, albuminuria, circulating uric acid levels and oxidative stress. On the other hand, small increases in low-density lipoprotein (LDL)-cholesterol levels have also been observed for the class, which theoretically might offset some of these benefits. The potential translational impact of these effects is being tested with outcome trials, also reviewed in this article, powered to assess both macrovascular as well as certain microvascular outcomes in T2DM. These are expected to begin to report in late 2015.