Body Composition in Asians and Caucasians: Comparative Analyses and Influences on Cardiometabolic Outcomes

The Immune System in Obesity: Developing Paradigms Amidst Inconvenient Truths

PURPOSE OF REVIEW

Adipose tissue (AT) houses both innate and adaptive immune systems that are crucial for preserving AT function and metabolic homeostasis. In this review, we summarize recent information regarding progression of obesity-associated AT inflammation and insulin resistance. We additionally consider alterations in AT distribution and the immune system in males vs. females and among different racial populations.

RECENT FINDINGS

Innate and adaptive immune cell-derived inflammation drives insulin resistance both locally and systemically. However, new evidence also suggests that the immune system is equally vital for adipocyte differentiation and protection from ectopic lipid deposition. Furthermore, roles of anti-inflammatory immune cells such as regulatory T cells, "M2-like" macrophages, eosinophils, and mast cells are being explored, primarily due to promise of immunotherapeutic applications. Both immune responses and AT distribution are strongly influenced by factors like sex and race, which have been largely underappreciated in the field of metabolically-associated inflammation, or meta-flammation. More studies are required to recognize factors that switch inflammation from controlled to uncontrolled in obesity-associated pathogenesis and to integrate the combined effects of meta-flammation and immunometabolism. It is critical to recognize that the AT-associated immune system can be alternately beneficial and destructive; therefore, simply blocking immune responses early in obesity may not be the best clinical approach. The dearth of information on gender and race-associated disparities in metabolism, AT distribution, and the immune system suggest that a greater understanding of such differences will be critical to develop personalized treatments for obesity and the associated metabolic dysfunction.

Does the ingestion of a 24 hour low glycaemic index Asian mixed meal diet improve glycaemic response and promote fat oxidation? A controlled, randomized cross-over study

BACKGROUND

The health benefits of consuming a low glycaemic index (GI) diet to reduce the risk of type 2 Diabetes are well recognized. In recent years the GI values of various foods have been determined. Their efficacy in constructing and consuming a low GI diet over 24 h in modulating glycaemic response has not been fully documented. The translation of using single-point GI values of foods to develop a 24 h mixed meal diet can provide valuable information to consumers, researchers and dietitians to optimize food choice for glycaemic control. By using GI values of foods to develop mixed meals, our study is the first to determine how both blood glucose and substrate oxidation may be modulated over 24 h.

METHODS

The study included 11 Asian men with a BMI between 17-24 kg/m² who followed both a 1-day low GI and 1-day high GI diet in a randomized, controlled cross-over design. Test meals included breakfast, lunch, snack and dinner. Glycaemic response was measured continuously for over 24 h and postprandial substrate oxidation for 10 h inside a whole body calorimeter.

RESULTS

The low GI diet resulted in lower 24 h glucose iAUC (860 ± 440 vs 1329 ± 614 mmol/L.min; p = 0.014) with lower postprandial glucose iAUC after breakfast (p < 0.001), lunch (p = 0.009), snack (p = 0.012) and dinner (p = 0.003). Moreover, 24 h mean amplitude of glycaemic excursion was lower during the low GI vs high GI diet (1.44 ± 0.63 vs 2.33 ± 0.82 mmol/L; p < 0.001). Simultaneously, decrease in 10 h fat oxidation was less during the low vs high GI diet (-0.033 ± 0.021 vs -0.050 ± 0.017 g/min; p < 0.001), specifically after breakfast (p < 0.001) and lunch (p < 0.001).

CONCLUSIONS

Our study corroborates that using low GI local foods to construct a 24 h low GI diet, is able to reduce glycaemic response and variability as recorded by continuous glucose monitoring. Our observations also confirm that a low GI diet promotes fat oxidation over carbohydrate oxidation when compared to a high GI diet. These observations provide public health support for the encouragement of healthier nutrition choices by consuming low GI foods.

TRIAL REGISTRATION

NCT 02631083 (Clinicaltrials.gov).

Combination therapy with GLP-1 analogues and SGLT-2 inhibitors in the management of diabesity: the real world experience

Diabesity-obesity resulting in diabetes-is a major health problem globally because of the obesity epidemic. Several anti-diabetic medications cause weight gain and may worsen obesity, and possibly diabeisty. Two recent small retrospective cohort studies showed weight loss and diabetes improvement with combination of glucagon-like peptide-1 (GLP-1) agonists and sodium-glucose co-transporter type-2 (SGLT-2) inhibitors in obese subjects. We assessed the effect of combination therapy with GLP-1 agonists and SGLT-2 inhibitors in the management of diabesity in a retrospective study at the Wolverhampton Diabetes Centre. Out of 79 patients on this combination regimen with other anti-diabetic medications, 37 cases who had follow up at 3-6 months were studied. Mean age and duration of follow up were 57.4 (+/-7.8) and 139 (+/-32.6) days, respectively. Twenty-two patients (59.5 %) were Asians. Statistically significant improvements in clinical parameters such as body weight reduction (3.07 kg), glycated haemoglobin (HbA1c) reduction (1.05 %), lower BMI (-1.13 kg/M²) and insulin dose reduction (6.8 units) were observed (p < 0.05 for all) in patients on combination regimen. Linear regression analysis showed that baseline HbA1c and baseline insulin dose were independent predictors of HbA1c reduction and insulin dose reduction, respectively. Our results suggest that combination therapy with GLP-1 agonists and SGLT-2 inhibitors is a promising option for patients with diabesity.

Body composition-derived BMI cut-offs for overweight and obesity in Indians and Creoles of Mauritius: comparison with Caucasians

BACKGROUND AND AIMS

Global estimates of overweight and obesity prevalence are based on the World Health Organisation (WHO) body mass index (BMI) cut-off values of 25 and 30 kg m-2, respectively. To validate these BMI cut-offs for adiposity in the island population of Mauritius, we assessed the relationship between BMI and measured body fat mass in this population according to gender and ethnicity.

METHODS

In 175 young adult Mauritians (age 20-42 years) belonging to the two main ethnic groups-Indians (South Asian descent) and Creoles (African/Malagasy descent), body weight, height and waist circumference (WC) were measured, total body fat assessed by deuterium oxide (D2O) dilution and trunk (abdominal) fat by segmental bioimpedance analysis.

RESULTS

Compared to body fat% predicted from BMI using Caucasian-based equations, body fat% assessed by D2O dilution in Mauritians was higher by 3-5 units in Indian men and women as well as in Creole women, but not in Creole men. This gender-specific ethnic difference in body composition between Indians and Creoles is reflected in their BMI-Fat% relationships, as well as in their WC-Trunk Fat% relationships. Overall, WHO BMI cut-offs of 25 and 30 kg m-2 for overweight and obesity, respectively, seem valid only for Creole men (~24 and 29.5, respectively), but not for Creole women whose BMI cut-offs are 2-4 units lower (21-22 for overweight; 27-28 for obese) nor for Indian men and women whose BMI cut-offs are 3-4 units lower (21-22 for overweight; 26-27 for obese).

CONCLUSIONS

The use of BMI cut-off points for classifying overweight and obesity need to take into account both ethnicity and gender to avoid gross adiposity status misclassification in this population known to be at high risk for type-2 diabetes and cardiovascular diseases. This is particularly of importance in obesity prevention strategies both in clinical medicine and public health.

Calcification of arteries supplying the gastric tube increases the risk of anastomotic leakage after esophagectomy with cervical anastomosis

BACKGROUND

Anastomotic leak is an important cause of morbidity and mortality after esophagectomy for esophageal cancer patients. Calcification of the arteries supplying the gastric tube has been found to be associated with leakage after esophagectomy with cervical anastomosis in Europeans. The purpose of this study is to evaluate the association between calcifications of the supplying arteries of the gastric tube and the occurrence of anastomotic leakage after esophagectomy with cervical anastomosis in Chinese patients with esophageal cancer.

METHODS

The demographic, clinical, and pathological features as well as the vascular calcification of arteries of 709 esophageal cancer patients who had undergone esophagectomies with cervical anastomosis were analyzed. Univariable and multivariable logistic regression were used to identify the association between the postoperative anastomotic leakage and calcifications of the arteries supplying the gastric tube.

RESULTS

Among the 709 patients, 122 (17.2%) had developed anastomotic leakage. Thirty-day mortality and length of hospital stay were higher for patients with anastomotic leakage. Upper digestive tract ulcer, peripheral vascular disease, renal insufficiency, American society of Anesthesiologists (ASA) risk class, and calcifications of aorta and celiac axis were found to be independent risk factors for the anastomotic leakage.

CONCLUSIONS

Calcification of the aorta and celiac axis that supply the gastric tube is an independent risk factor for cervical anastomotic leakage after esophagectomy in Chinese esophageal cancer patients.

Lean, but not healthy: the 'metabolically obese, normal-weight' phenotype

PURPOSE OF REVIEW

Obesity is commonly associated with metabolic dysfunction but there are obese persons who are metabolically healthy. On the opposite side of the coin, there are lean persons who carry multiple cardiometabolic risk factors, typically referred to as metabolically obese, normal-weight (MONW). This has called into question our understanding of obesity and metabolic dysfunction, as an appearance of normal weight may mask significant comorbidities and delay health interventions.

RECENT FINDINGS

High heterogeneity in MONW prevalence rates has been observed, with estimates ranging from as low as 5% to as high as 45%. Reasons for this include sample size effects, differences in MONW definition, social and demographic factors, as well as assumptions made in establishing normal weight. MONW study participants are often characterized by excess visceral adipose tissue and ectopic fat deposition, adipose tissue inflammation, altered inflammatory and adipokine profiles, reduced skeletal muscle mass and low cardiorespiratory fitness. However, more often than not, groups of MONW study participants have been somewhat 'fatter' than the control groups of metabolically healthy lean study participants, which in itself could be responsible for some of the observed differences. Very limited data are available regarding interventions to improve metabolic function in MONW study participants.

SUMMARY

There is a need for more research to better understand the characteristics of the MONW phenotype, the cause of metabolic dysfunction in the absence of obesity, and evaluate potential therapies so as to facilitate the establishment of clinical guidelines.

Maternal depression and mental health in early childhood: an examination of underlying mechanisms in low-income and middle-income countries

Studies examining mechanisms underlying associations between maternal depression and adverse child outcomes (including behaviour, socioemotional adjustment, and emotion regulation) indicate that during pregnancy, maternal depression could affect child outcomes through altered placental function, epigenetic changes in the child, and stress reactivity. Infection and dietary deficiencies in the mother and the child, together with the child's genetic vulnerability, might also affect outcome. Postnatally, associations between maternal depression and child outcome are influenced by altered mother-child interactions, sociodemographic or environmental influences, and social support. Knowledge is scarce on mechanisms in low-income and middle-income countries where maternal depression is highly prevalent, and stressful factors that influence the development of perinatal maternal depression and adverse child outcome (eg, food insecurity, perinatal infections, crowded or rural living conditions, and interpersonal violence) are both more intense and more common than in high-income countries. We reviewed evidence and use the biopsychosocial model to illustrate risk factors, mediators and moderators underlying associations between maternal depression and child outcomes in low-income and middle-income countries.

Technical Details of an Anterior Approach to the Superior Mesenteric Artery During Pancreaticoduodenectomy

INTRODUCTION

Use of central vascular ligation during dissection around the superior mesenteric artery (SMA) in pancreaticoduodenectomy (PD) for periampullary malignancies has rarely been documented.

METHODS

We developed the SMA hanging technique (SHT) to facilitate central vascular ligation during PD. Briefly, SMA dissection was initiated using the supracolic anterior approach, followed by left-sided dissection. The SMA was taped under finger guidance immediately after right-sided dissection. The ligament of Treitz was detached from the SMA during left-sided dissection, facilitating adequate lymph node dissection while preserving the nerve plexus around the SMA. Forty-seven consecutive patients who underwent PD for periampullary malignancies were divided into two groups: 23 underwent SHT and 24 underwent conventional dissection. Patients' clinical results were assessed to evaluate the feasibility and validity of SHT.

RESULTS

Blood loss volume, operation duration, and the incidence of bleeding during SMA dissection were significantly lower in the SHT group than in the conventional group. The short-term and oncological results were similarly acceptable in both groups.

CONCLUSIONS

SHT is a feasible and safe technique with acceptable short-term outcomes. We propose the use of this procedure to standardize en bloc dissection around the SMA.

The effect of diabetes mellitus on outcomes of patients with nosocomial pneumonia caused by methicillin-resistant Staphylococcus aureus: data from a prospective double-blind clinical trial comparing treatment with linezolid versus vancomycin

Background

The presence of diabetes mellitus increases the risk of several severe infections, but data on its effect on treatment outcomes in patients with nosocomial pneumonia (NP) caused by methicillin-resistant Staphylococcus aureus (MRSA) are limited.

Methods

We retrospectively analyzed data from a double-blind, randomized, multi-center, international clinical trial of culture-confirmed MRSA NP that compared treatment with linezolid to vancomycin. Specifically, we evaluated the clinical and microbiologic outcomes of patients with and without diabetes in the modified intent to treat population at end-of-treatment (EOT) and end-of-study (EOS, 7–30 days post-EOT).

Results

Among 448 enrolled patients 183 (40.8 %) had diabetes mellitus, 87 (47.5 %) of whom received linezolid and 96 (52.5 %) vancomycin. Baseline demographic and clinical characteristics were similar for the two treatment groups. Clinical success rates at EOS were 57.6 % with linezolid and 39.3 % with vancomycin, while microbiological success rates were 58.9 % with linezolid and 41.1 % with vancomycin. Among diabetic patients, rates of mortality and study drug-related adverse effects were similar between the treatment groups. Overall day 28 mortality rates were higher among diabetic patients compared to non-diabetic patients (23.5 vs 14.7 %, respectively: RD = 8.8 %, 95 % CI [1.4, 16.3]).

Conclusions

Among diabetic patients with MRSA NP, treatment with linezolid, compared to vancomycin, was associated with higher clinical and microbiologic success rates, and comparable adverse event rates.

Trial registration

NCT00084266.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-1779-5) contains supplementary material, which is available to authorized users.

Obesity Is Associated With Increased Morbidity in Moderate to Severe COPD

BACKGROUND

Obesity is prevalent in the United States; however, the impact of obesity on COPD morbidity is unclear. We hypothesized that obesity is associated with worse outcomes in COPD.

METHODS

We examined 3,631 participants from the multicenter prospective cohort study Genetic Epidemiology of COPD (COPDGene) who had spirometry-confirmed COPD, a postbronchodilator FEV₁ < 80% predicted, and a BMI ≥ 18.5 kg/m². We conducted logistic and linear regression analyses to determine the association between COPD outcomes and obesity class, adjusting for relevant confounders. The referent for obesity classes included normal/overweight individuals (BMI range, 18.5-29.9 kg/m²).

RESULTS

Overall, 35% of participants were obese, with 21% class I (BMI range, 30-34.9 kg/m²), 9% class II (BMI range, 35-39.9 kg/m²), and 5% class III (BMI ≥ 40 kg/m²). The number of comorbidities increased with increasing obesity class (P < .001). Increasing obesity class was independently associated with worse respiratory-specific and general quality of life (QOL) (St. George's Respiratory Questionnaire score and Short Form-36 score version 2, respectively), reduced 6-min walk distance (6MWD), increased dyspnea (Modified Medical Research Council score ≥ 2), and greater odds of severe acute exacerbation of COPD (AECOPD). The associations between obesity and worse outcomes were independent of the presence of comorbidities, except in the case of SF-36 and severe exacerbations.

CONCLUSIONS

Obesity is prevalent among individuals with COPD and associated with worse COPD-related outcomes, ranging from QOL and dyspnea to 6MWD and severe AECOPD. These associations were strengthened when obesity was analyzed as a dose-dependent response. Obesity in patients with COPD may contribute to a worse COPD-related course.