Frequencies of obesity susceptibility alleles among ethnically and racially diverse bariatric patient populations

Peri-Operative Glycemic Dynamics in a Chinese Patient With Type 2 Diabetes Undergoing Laparoscopic Sleeve Gastrectomy

Obesity and type 2 diabetes (T2D) are prevalent issues in China. Bariatric and metabolic surgery, by reducing the size of the stomach through the removal of a portion of the stomach using laparoscopy (laparoscopic sleeve gastrectomy (LSG)), induces the remarkable remission of T2D inpatients. Plasma glucose (PG) was reported to be at a lower than normal level in Caucasian patients a few weeks after surgery, which is not well-documented in Chinese patients who have a lower body mass index (BMI) compared to Caucasians. Thus, we adopted the use of a continuous glucose monitoring system (CGMS) in a Chinese patient to monitor postoperative glucose levels. We found that the level of PG lowered to the normal range four days after LSG surgery while weight loss was not significantly reduced. It is indicated that the main mechanism of LSG inducing remission of T2DM is the limitation of food intake in addition to the imbalance of a few gastrointestinal hormones such as glucagon-like peptide 1 (GLP-1), Ghrelin. The lower the BMI, the lower the adipose tissue, and the faster the decrease in PG after bariatric and metabolic surgery.

Racial Disparity in 30-Day Outcomes of Metabolic and Bariatric Surgery

Background

There is evidence of racial disparity in the long-term weight loss outcomes of bariatric surgery. However, there has been a more limited evaluation of the impact of race on immediate perioperative outcomes. The aim of this study was to compare 30-day postoperative outcomes among different races.

Study Design

The 2016 Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP) database was queried to identify patients aged ≥ 18 and body mass index ≥ 35 who underwent primary laparoscopic Roux-en-Y gastric bypass (LRYGB) or laparoscopic sleeve gastrectomy (LSG) with known information on race. We then evaluated the effect of five different races on four different 30-day outcomes.

Results

Of the total 106,932 patients (79.5% White, 19.3% African American (AA), 0.5% Asian, 0.4% American Indian or Alaska Native, 0.3% Native Hawaiian or other Pacific Islander), 30-day rates of postoperative complication, readmission, re-intervention, and reoperation were 6, 3.8, 1.3, and 1.2%, respectively. After controlling for other covariates in multivariate logistic regression and selecting White as reference, AA was the only race associated with a higher risk of postoperative complications (odds ratio [OR] 1.13; confidence interval [CI] 1.06–1.2) and readmissions (OR 1.47; CI 1.3–1.6). AA and American Indian or Alaska Native were also associated with higher re-interventions (OR 1.31; CI 1.15–1.51 and OR 2.11; CI 1.03–4.34). Furthermore, AA was associated with lower 30-day reoperations (OR 0.83; CI 0.7–0.9).

Conclusion

This study found significant racial differences in short-term outcomes following bariatric surgery. Factors underlying these disparities are unclear and warrant further investigation.

The Impact of Ethnic Differences Between Israeli-Jews and Israeli-Arabs on Post-bariatric Surgery Weight Loss: a Prospective Cohort Analysis

Previous studies from different countries have shown that ethnic diversity may have an important effect on clinical outcome following bariatric procedures. Israel has an ethnic diverse population but there is limited information about this effect on surgery outcome. We carried out a 3-year institutional, prospective comparative data collection study among Jewish and Arab patients in Israel undergoing primary bariatric surgery. Percent of total weight loss (%TWL) and change in body mass index (BMI) were assessed. The results revealed no difference between Arab and Jewish participants in %TWL nor BMI change. Differences in absolute BMI values were all accounted for by the initial between-group difference in the pre-operative BMI. Comorbidity resolution at 1 year post-surgery was not significantly different between the groups.

Genetics of Obesity in East Asians

Obesity has become a public health problem worldwide. Compared with Europe, people in Asia tend to suffer from type 2 diabetes with a lower body mass index (BMI). Genome-wide association studies (GWASs) have identified over 750 loci associated with obesity. Although the majority of GWAS results were conducted in individuals of European ancestry, a recent GWAS in individuals of Asian ancestry has made a significant contribution to the identification of obesity susceptibility loci. Indeed, owing to the multifactorial character of obesity with a strong environmental component, the revealed loci may have distinct contributions in different ancestral genetic backgrounds and in different environments as presented through diet and exercise among other factors. Uncovering novel, yet unrevealed genes in non-European ancestries may further contribute to explaining the missing heritability for BMI. In this review, we aimed to summarize recent advances in obesity genetics in individuals of Asian ancestry. We therefore compared proposed mechanisms underlying susceptibility loci for obesity associated with individuals of European and Asian ancestries and discussed whether known genetic variants might explain ethnic differences in obesity risk. We further acknowledged that GWAS implemented in individuals of Asian ancestries have not only validated the potential role of previously specified obesity susceptibility loci but also exposed novel ones, which have been missed in the initial genetic studies in individuals of European ancestries. Thus, multi-ethnic studies have a great potential not only to contribute to a better understanding of the complex etiology of human obesity but also potentially of ethnic differences in the prevalence of obesity, which may ultimately pave new avenues in more targeted and personalized obesity treatments.

Poor Health Behaviors Prior to Laparoscopic Sleeve Gastrectomy Surgery

INTRODUCTION

Identifying eating and lifestyle behaviors prior to bariatric surgery may assist in better selecting and preparing patients and might lead to improved success rate. The current study aimed to assess eating behaviors and lifestyle trends among laparoscopic sleeve gastrectomy (LSG) candidates and to compare those trends between genders.

METHODS

This descriptive study was conducted in the bariatric clinic at the Haifa Assuta Medical Center. Data was gathered from medical records of LSG candidates that were evaluated before surgery in our institution between 2008 and 2011. The data included demographics, comorbidities, anthropometrics, weight management history, and lifestyle parameters. Eating pattern and eating habits were determined by eating habits questionnaires.

RESULTS

A total of 266 LSG surgery candidates (71.4 % female) with an average age of 40.7 ± 10.9 years and pre-surgery BMI of 42.4 ± 4.8 kg/m² were studied. More than half of the patients have family history of obesity and their onset of obesity was before the age of 18 years (54.5 and 57.9 %, respectively). Most of the patients reported on poor eating habits and sedentary lifestyle: 65.1 % do not eat regular meals, 70.3 % skip over breakfast, 61.9 % presented loss of control eating, 45 % frequently consume sweets, and 80.1 % were classified as none active. There were no differences in eating patterns or lifestyle parameters between genders.

CONCLUSION

High occurrence of unhealthy eating habits and a non-active lifestyle were detected in morbid obese candidates for LSG surgery. More efforts should be directed towards nutritional and lifestyle education prior to the surgery.

Ethnic Considerations for Metabolic Surgery

Obesity and diabetes represent twin health concerns in the developed world. Metabolic surgery has emerged as an established and enduring treatment for both obesity and diabetes. As the burden of obesity and diabetes varies upon the basis of ethnicity, it is also apparent that there may be differences for indications and outcomes for different ethnic groups after metabolic surgery. Whereas there appears to be evidence for variation in weight loss and complications for different ethnic groups, comorbidity remission particularly for diabetes appears to be free of ethnic disparity after metabolic surgery. The impacts of access, biology, culture, genetics, procedure, and socioeconomic status upon metabolic surgery outcomes are examined. Further refinement of the influence of ethnicity upon metabolic surgery outcomes is likely imminent.

The genetics of human obesity

The heritability of obesity has long been appreciated and the genetics of obesity has been the focus of intensive study for decades. Early studies elucidating genetic factors involved in rare monogenic and syndromic forms of extreme obesity focused attention on dysfunction of hypothalamic leptin-related pathways in the control of food intake as a major contributor. Subsequent genome-wide association studies of common genetic variants identified novel loci that are involved in more common forms of obesity across populations of diverse ethnicities and ages. The subsequent search for factors contributing to the heritability of obesity not explained by these 2 approaches ("missing heritability") has revealed additional rare variants, copy number variants, and epigenetic changes that contribute. Although clinical applications of these findings have been limited to date, the increasing understanding of the interplay of these genetic factors with environmental conditions, such as the increased availability of high calorie foods and decreased energy expenditure of sedentary lifestyles, promises to accelerate the translation of genetic findings into more successful preventive and therapeutic interventions.

Effects of FTO RS9939906 and MC4R RS17782313 on obesity, type 2 diabetes mellitus and blood pressure in patients with hypertension

Background

Genetic variants of the FTO gene rs9939609 A/T and the MC4R gene rs17782313 C/T have been associated with obesity. Individuals with mutations in MC4R gene have lower blood pressure (BP), independently of obesity. This study aimed to investigate the association of FTO rs9939609 and MC4R rs17782313 with anthropometric indexes, BP, and type 2 diabetes mellitus among hypertensive patients.

Methods

We genotyped 217 individuals (86 men and 131 women) with hypertension (systolic or diastolic BP ≥ 140/90 mmHg or using antihypertensive drugs). Diabetes mellitus was diagnosed according to the American Diabetes Association criteria. Waist and neck circumferences (cm), Body Adiposity Index (BAI,%), Lipid Accumulation Product Index (LAP, cm.mmol.l) and body mass index (BMI, kg/m²) were analyzed using analysis of covariance or modified Poisson’s regression.

Results

Rare allele frequencies were 0.40 for A for FTO rs9939609 and 0.18 for C for MC4R rs17782313. A positive association of FTO rs9939609 and MC4R rs17782313 with BMI was observed in the overall sample. Among men and women, neck circumference was associated with the FTO genotype and, for women, MC4R genotype. In contrast, in men we found a negative association of MC4R rs17782313 with diastolic BP (TT 90.1 ±12.2, TC/CC 83.2 ±12.1; P = 0.03) and borderline association for systolic BP after controlling for age and BMI.

Conclusions

Common genetic variants of FTO rs9939609 have positive associations with BMI and neck circumference and MC4R rs17782313 in women, but a negative association with diastolic and mean blood pressure in men with hypertension.

Obesity surgery: happy with less or eternally hungry?

The superior efficacy of bariatric surgery compared with intensive medical treatment in reversing metabolic disease is now well accepted, but the critical mechanisms remain unknown. Unlike dieting, which triggers strong counter-regulatory responses such as hunger and craving, some obesity surgeries appear to permanently reset the level of defended body weight. Understanding the molecular mechanisms behind successful surgery would thus go a long way in developing future 'knifeless' treatment options. Major candidates include changes in gut-brain signaling by hormones, bile acids, and other still unidentified factors. By re-sensitizing homeostatic regulatory circuits in the hypothalamus and hedonic-motivational processing in corticolimbic systems to internal signals, bariatric surgery could thus lead to a state of being content with less.