Waist circumference as a vital sign in cardiology 20 years after its initial publication in the American Journal of Cardiology

Markers of insulin resistance in Polycystic ovary syndrome women: An update

Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders, affecting 5%-10% of women of reproductive age. The importance of this syndrome lies in the magnitude of associated comorbidities: infertility, metabolic dysfunction, cardiovascular disease (CVD), plus psychological and oncological complications. Insulin resistance (IR) is a prominent feature of PCOS with a prevalence of 35%-80%. Without adequate management, IR with compensatory hyperinsulinemia contributes directly to reproductive dysfunction in women with PCOS. Furthermore, epidemiological data shows compelling evidence that PCOS is associated with an increased risk of impaired glucose tolerance, gestational diabetes mellitus and type 2 diabetes. In addition, metabolic dysfunction leads to a risk for CVD that increases with aging in women with PCOS. Indeed, the severity of IR in women with PCOS is associated with the amount of abdominal obesity, even in lean women with PCOS. Given these drastic implications, it is important to diagnose and treat insulin resistance as early as possible. Many markers have been proposed. However, quantitative assessment of IR in clinical practice remains a major challenge. The gold standard method for assessing insulin sensitivity is the hyperinsulinemic euglycemic glucose clamp. However, it is not used routinely because of the complexity of its procedure. Consequently, there has been an urgent need for surrogate markers of IR that are more applicable in large population-based epidemiological investigations. Despite this, many of them are either difficult to apply in routine clinical practice or useless for women with PCOS. Considering this difficulty, there is still a need for an accurate marker for easy, early detection and assessment of IR in women with PCOS. This review highlights markers of IR already used in women with PCOS, including new markers recently reported in literature, and it establishes a new classification for these markers.

Chinese Adults Are More Susceptible to Effects of Overall Obesity and Fat Distribution on Cardiometabolic Risk Factors

CONTEXT

The body mass index (BMI) and waist circumference (WC) as diagnostic tools of obesity do not reflect the same level of fat mass and whether obesity leads to various effects on cardiometabolic risk factors among different racial/ethnic population is unknown.

OBJECTIVE

The study aims to address the multicollinearity between BMI and WC by using the residual model approach and to assess and compare the effects of obesity metrics on cardiometabolic risk factors among different races/ethnicities.

DESIGN, SETTING, AND PARTICIPANTS

Data from a nationally representative sample of mainland Chinese adults collected in 2010 and data from the National Health and Nutrition Evaluation Survey 2005-2016 were used. By conducting a regression analysis between WC and BMI, the variation of BMI was removed from WC measures and residual of WC was obtained. The associations between obesity metrics and cardiometabolic risk factors were compared among different races/ethnicities by sex.

RESULTS

The residual WC was significantly associated with all the cardiometabolic risk factors in mainland Chinese, and most of the factors in non-Hispanic white and non-Hispanic black adults, but not in the other races/ethnicities. The standardized regression coefficients of the associations between obesity metrics and cardiometabolic factors showed that the obesity metrics had greater impact on systolic blood pressure, diastolic blood pressure, and triglyceride in Chinese adults than those of other racial/ethnic groups.

CONCLUSIONS

Chinese adults are more susceptible to the effects of overall obesity and fat distribution on cardiometabolic risk factors than the other racial/ethnic population.

Changes in Body Adiposity, Dietary Intake, Physical Activity and Quality of Life of Obese Individuals Submitted to Intragastric Balloon Therapy for 6 Months

BACKGROUND

Obesity is an important risk factor for several chronic diseases and also is associated with worse quality of life. Intragastric balloon (IGB) is an effective method for weight loss. Although changes in lifestyle are critical to weight loss during and after IGB therapy, only a few studies evaluated dietary intake and none evaluated changes in physical activity with a validated questionnaire during the treatment. The aim of this study was to evaluate changes in total and central body adiposity, dietary intake, physical activity, and quality of life of patients with obesity submitted to IGB treatment for 6 months.

METHODS

Prospective observational study involving 42 patients with obesity using IGB for 6 months. The patients were evaluated, on the day of insertion and withdrawal or adjustment of IGB for total and central body adiposity (anthropometry and bioelectrical impedance), dietary intake, physical activity (Baecke questionnaire), and quality of life (SF-36 questionnaire).

RESULTS

There was a significant decrease in total and central body adiposity. The mean % total weight loss and % excess weight loss were 15.88 ± 1.42 and 56.04 ± 4.90, respectively and waist circumference decreased 13.33 ± 1.39 cm. There was a reduction in energy intake, an increase in physical activity, and an improvement of quality of life during IGB treatment.

CONCLUSION

The present study suggests that IGB treatment during 6 months in individuals with obesity is effective for decreasing total and central body adiposity being associated with reduction in energy intake, increase in physical activity, and improvement in quality of life.

Therapeutic Treatment for Abdominal Obesity in Adults

BACKGROUND

Abdominal obesity, an accumulation of fat in the abdominal region, is a risk factor for several non-communicable diseases. This review aims to identify non-surgical treatment options for abdominal obesity in adults. Interventions with behavioral, dietary, physical activity, or pharmaceutical components were compared to control conditions.

METHODS

A systematic literature research for randomized controlled trials was conducted in Medline, Embase, and the Cochrane Central Register of Controlled Trials according to a prespecified and registered protocol (PROSPERO CRD42017057898).

RESULTS

Out of 2954 articles, 15 studies with 2918 participants remained after applying inclusion and exclusion criteria. Altogether the programs achieved a -2.65cm (95% confidence interval (CI) [-3.77, -1.53]) reduction in waist circumference (WC), as a measure of abdominal obesity. Eight behavioral interventions reduced WC by -1.88cm (95% CI [-2.55, -1.22]), and six combined interventions with behavioral plus dietary and/or physical activity components by -4.11cm (95% CI [-6.17, -2.05]). The only pharmaceutical trial did not find any effect on WC.

CONCLUSION

Overall, the identified interventions showed a moderate effect on WC. One reason may be that in most studies WC was a secondary outcome parameter, while only a small number of interventions primarily targeted abdominal obesity. Further research regarding the treatment of abdominal obesity is urgently needed.

Is there a relationship between vitamin D nutritional status and metabolic syndrome in childhood acute lymphoblastic leukemia survivors? A PETALE study

BACKGROUND

Treatment of childhood acute lymphoblastic leukemia (cALL) has reached unprecedented success leading to survival rates reaching 90%. This is regrettably linked to increased risk of developing long-term health-related sequels into early adulthood.

OBJECTIVE

This study aims at assessing the relationship between the vitamin D status and metabolic biomarkers in PETALE, a well-characterized cohort of cALL survivors.

RESULTS

We demonstrate that 15.9% of the study participants exhibited 3 or more metabolic syndrome (MetS) risk factors. We also show a direct relationship between s25OHD₃ and plasma HDL-Cholesterol concentrations in female but not male participants.

CONCLUSION

Our data, from a metabolically well-described cohort, support a modest role for vitamin D in lipid metabolism in childhood leukemia survivors. The major outcome of this study is the strong association between HDL-Cholesterol concentration and s25OHD₃ only in female subjects, thereby conveying vitamin D a gender-specific cardio-protective effect. cALL survivors represent a population at higher risk for secondary diseases. For this reason thorough nutritional evaluation, including vitamin D should be part of the regular follow-up.

Association between exercise-induced change in body composition and change in cardiometabolic risk factors in postmenopausal South Asian women

The South Asian population suffers from a high prevalence of type 2 diabetes and cardiovascular disease (CVD). A unique obesity phenotype of elevated visceral adipose tissue (VAT) is associated with CVD risk among South Asians. Exercise-induced reduction in VAT and body fat is an effective mechanism to improve cardiometabolic risk factors but this has not been shown in South Asians. Whether exercise-induced changes in measurements such as waist circumference (WC) are independently related to changes in cardiometabolic risk factors in South Asians is unknown. Multi-slice computed tomography scanning was used to assess VAT, cardiometabolic risk factors through a fasting blood sample, and body fat using dual-energy X-ray absorptiometry. Forty- nine postmenopausal South Asian women who participated in two 12-week aerobic exercise programs were included. Bivariate correlations were used to assess associations between change in cardiometabolic risk factors and change in body composition. Regression analyses were conducted with change in glucose, insulin, and homeostatic model assessment of insulin resistance (HOMA-IR) as dependent variables and change in body composition as independent variables of interest. There were significant associations between changes in fasting insulin, glucose, and HOMA-IR with change in VAT. The association between change in VAT and these cardiometabolic risk factors was independent of change in other body composition variables of interest. South Asian women should be encouraged to engage in aerobic activity to reduce their risk of type 2 diabetes and CVD, and physicians should be aware of improvements in glucose regulation with exercise training not observed through reductions in WC.

Single and combined effects of body composition phenotypes on carotid intima-media thickness

BACKGROUND

Central fatness might be a more sensitive predictor of atherosclerotic changes in children than are total body fat measures. However, it is unclear whether a total body fat measure coupled with an estimate of a more central pattern of fat accumulation predicts increased carotid intima-media-thickness (cIMT) better than either measure alone.

OBJECTIVE

The objective of the study is to identify the ability of a combination of simple anthropometric screening tools or a combination of objective measures of body composition to predict cIMT.

METHODS

cIMT was assessed on the common carotid artery in 349 children aged 11-12 years old (183 girls). Body mass index (BMI), waist circumference (WC) and waist-to-height ratio (WHtR) were dichotomized according to established criteria and indices of total body (TBFI) and abdominal (ABFMI) fat were assessed by dual-energy X-ray absorptiometry and categorized (increased risk ≥85%). Single and combined associations among anthropometric and laboratorial measures with the risk of having increased cIMT (≥85%) and discriminatory performance were tested with logistic regression analysis and Receiver Operator Curve analysis.

RESULTS

Children with higher total fatness (BMI and TBFI) or higher central pattern of fat accumulation (WC, WHtR and BFMI) were in higher risk for increased cIMT [odds ratio (OR): 2.08-3.24). The risk for increased cIMT was not higher among children who coupled high total and high central fatness (OR: 2.27-3.10).

CONCLUSIONS

Combination of total and central measures of fat does not improve the prediction of increased cIMT in children. Simple surrogate measures of fatness can be used to predict increased cIMT urging special attention to those children who exhibit increased abdominal fat.

Usefulness of measuring both body mass index and waist circumference for the estimation of visceral adiposity and related cardiometabolic risk profile (from the INSPIRE ME IAA study)

Despite its well-documented relation with visceral adiposity (VAT) and cardiometabolic risk (CMR), whether waist circumference (WC) should be measured in addition to body mass index (BMI) remains debated. This study tested the relevance of adding WC to BMI for the estimation of VAT and CMR. In the International Study of Prediction of Intra-abdominal Adiposity and Its Relationship with Cardiometabolic Risk/Intra-abdominal Adiposity, 297 physicians recruited 4,504 patients (29 countries). Both BMI and WC were measured, whereas VAT and liver fat were assessed by computed tomography. A composite CMR score was calculated. From the 4,109 patients included in the present analyses (20 ≤ BMI < 40 kg/m(2), 47% women), about 30% displayed discordant values for WC and BMI quintiles, despite a strong correlation between the 2 anthropometric variables (r = 0.87 and r = 0.84 for men and women, respectively, p <0.001). Within each single BMI unit, VAT and WC showed substantial variability between subjects (mean difference between 90th and 10th percentiles: 175 cm(2)/16 cm and 137 cm(2)/18 cm for VAT/WC in men and women, respectively). Within each BMI category, increasing gender-specific WC tertiles were associated with significantly higher VAT, liver fat, and with a more adverse CMR profile. In conclusion, this large international cardiometabolic study highlights the frequent discordance between BMI and WC, driven by the substantial variability in VAT for a given BMI. Within each BMI category, WC was cross-sectionally associated with VAT, liver fat, and CMR factors. Thus, WC allows a further refinement of the CMR related to any given BMI.