Obesity epidemic: overview, pathophysiology, and the intensive care unit conundrum

Obesity-associated nonalcoholic fatty liver disease

Obesity is strongly associated with the prevalence of nonalcoholic fatty liver disease (NAFLD) in adult and pediatric populations. Nutrition, physical activity, and behavioral modifications are critical components of the treatment regimen for all obese patients with NAFLD. Bariatric surgeries that affect or restrict the flow of food through the gastrointestinal tract may improve liver histology in morbidly obese patients with nonalcoholic steatohepatitis (NASH), although randomized clinical trials and quasi-randomized clinical studies are lacking. Early detection of NASH and hepatic fibrosis using noninvasive biochemical and imaging markers that may replace liver biopsy is the current challenge.

Unconscious agendas in the etiology of refractory obesity and the role of hypnosis in their identification and resolution: a new paradigm for weight-management programs or a paradigm revisited?

Hypnosis has long been recognized as an effective tool for producing behavioral change in the eating disorders anorexia and bulimia. Despite many studies from the latter half of the last century suggesting that hypnosis might also be of value in managing obesity situations, the efficacy of hypnotherapy for weight reduction has received surprisingly little formal research attention since 2000. This review presents a brief history of early clinical studies using hypnosis for weight reduction and describes a hypnotherapeutic approach within which a combination of instructional/pedagogic and exploratory therapeutic sessions can work together synergistically to maximize the potential for sustained weight loss. Hypnotic modulation of appetite- and satiation-associated peptides and hormone levels may yield additional physiological benefits in Type 1 and Type 2 diabetes.

Body weight gain and serum leptin levels of non-overweight and overweight/obese pregnant women

Background

Our objective was to evaluate changes in serum leptin levels during pregnancy in overweight/obese and non-obese women and to assess total and percent weight gain during pregnancy as possible factors that influence leptin levels.

Material/Methods

In a prospective study of 42 low-risk pregnant women receiving prenatal care, we assessed serum leptin levels at gestational weeks 9–12, 25–28, and 34–37. Based on their pre-pregnancy body mass indices (BMIs), the cohort was divided into: non-overweight (BMI <25 kg/m²) and overweight/obese (BMI ≥25 kg/m²) subjects.

Results

We found a progressive increase in maternal weight gain during pregnancy in both groups. There was also a progressive increase in leptin levels in the 2 strata; however, the increase was significantly higher in the non-overweight patient group. We found that non-overweight pregnant women had a noticeably larger total weight gain. When analyzing the percent weight gain during pregnancy compared to the pre-pregnancy weight, the non-overweight group had a significantly greater percent weight gain than the overweight/obese group.

Conclusions

Our results suggest that the greater increase in leptin levels in non-overweight pregnant women can be explained by the higher percent weight gain in this group compared to overweight/obese women. These findings suggest that controlling the percent weight gain may be an important preventive measure when controlling leptin levels during pregnancy and subsequent medical complications.

Tragopogon porrifolius improves serum lipid profile and increases short-term satiety in rats

Tragopogon porrifolius (white salsify) is an edible plant commonly used in folk medicine in Lebanon and neighbouring countries. This study investigates the effect of the aqueous extract of the aerial part of T. porrifolius on lipemia and appetite regulation using a rat model. Food intake, abdominal fat percentage, blood lipid profile, liver weight and liver enzymes were assessed following 4 weeks of extract intake via drinking water (50, 100, or 250 mg/kg body weight) in standard high-carbohydrate and high-fat dietary conditions. In a separate study, the short term effect of a preload of T. porrifolius extract on food intake was evaluated. Results showed that consumption of the plant extract for a period of four weeks resulted in a marked improvement of the lipid profile (triglycerides, total cholesterol, LDL and HDL cholesterol). Body weight, food intake and intra-abdominal fat were also lower in animals given the plant extract (100 and 250 mg/kg). In addition, T. porrifolius extract preload produced a dose dependent decrease in food intake observed over 24h. The intake of T. porrifolius aqueous extract therefore improved lipemia and increased satiety in rats with no visible adverse effects.

Community-generated recommendations regarding the urban nutrition and tobacco environments: a photo-elicitation study in Philadelphia

Introduction

Overweight, obesity, and tobacco use are major preventable causes of disability, disease, and death. In 2010, 25% of Philadelphia adults smoked, and 66% were overweight or obese. To address these health threats, the Philadelphia Department of Public Health launched Get Healthy Philly, an initiative to improve the city’s nutrition, physical activity, and tobacco environments. The objective of this assessment was to identify residents’ perspectives on threats to health and opportunities for change in the local food and tobacco environments.

Methods

Participants (N = 48) took photographs to document their concerns regarding Philadelphia’s food and tobacco environments and participated in photo-elicitation interviews. We coded photographs and interview transcripts and identified key themes.

Results

Participants proposed interventions for nutrition 4 times more often than for tobacco. Participants spontaneously articulated the need for multilevel change consistent with the ecological model of health behavior, including changes to policies (food assistance program provisions to encourage healthful purchases), local and school environments (more healthful corner store inventories and school meals), and individual knowledge and behavior (healthier food purchases). Participants often required interviewer prompting to discuss tobacco, and they suggested interventions including changes in advertising (a local environmental concern) and cigarette taxes (a policy concern).

Conclusion

Participants were well versed in the relevance to health of nutrition and physical activity and the need for multilevel interventions. Their responses suggested community readiness for change. In contrast, participants’ more limited comments regarding tobacco suggested that prevention and control of tobacco use were perceived as less salient public health concerns.

Obesity management in gynecologic cancer survivors: provider practices and attitudes

OBJECTIVE

Obesity is associated with the development and risk of death from several women's cancers. The study objective was to describe and compare oncologic providers' attitudes and practices as they relate to obesity counseling and management in cancer survivors.

STUDY DESIGN

Society of Gynecologic Oncology members (n = 924) were surveyed with the use of a web-based, electronic questionnaire. χ(2) and Fisher exact tests were used to analyze responses.

RESULTS

Of the 240 respondents (30%), 92.9% were practicing gynecologic oncologists or fellows, and 5.1% were allied health professionals. Median age was 42 years; 50.8% of the respondents were female. Of the respondents, 42.7% reported that they themselves were overweight/obese and that ≥50% of their survivor patients were overweight/obese. Additionaly, 82% of the respondents believed that discussing weight would not harm the doctor-patient relationship. Most of the respondents (95%) agreed that addressing lifestyle modifications with survivors is important. Respondents believed that gynecologic oncologists (85.1%) and primary care providers (84.5%) were responsible for addressing obesity. More providers who were ≤42 years old reported undergoing obesity management training (P < .001) and were more likely to believe that survivors would benefit from obesity education than providers who were >42 years old (P = .017). After initial counseling, 81.5% of the respondents referred survivors to other providers for obesity interventions.

CONCLUSION

Oncology provider respondents believe that addressing obesity with cancer survivors is important. Providers believed themselves to be responsible for initial counseling but believed that obesity interventions should be directed by other specialists. Further research is needed to identify barriers to care for obese cancer survivors and to improve physician engagement with obesity counseling in the "teachable moment" that is provided by a new cancer diagnosis.

Rimonabant, gastrointestinal motility and obesity

Background:

Obesity and overweight affect more than half of the US population and are associated with a number of diseases. Rimonabant, a cannabinoid receptor 1 blocker in the endocannabinoid (EC) system, was indicated in Europe for the treatment of obesity and overweight patients with associated risk factors but withdrawn on Jan, 2009 because of side effects. Many studies have reported the effects of rimonabant on gastrointestinal (GI) motility and food intake.

The aims of this review are:

to review the relationship of EC system with GI motility and food intake;

to review the studies of rimonabant on GI motility, food intake and obesity;

and to report the tolerance and side effects of rimonabant.

Methods:

the literature (Pubmed database) was searched using keywords: rimonabant, obesity and GI motility.

Results:

GI motility is related with appetite, food intake and nutrients absorption. The EC system inhibits GI motility, reduces emesis and increases food intake; Rimonabant accelerates gastric emptying and intestinal transition but decreases energy metabolism and food intake. There is rapid onset of tolerance to the prokinetic effect of rimonabant. The main side effects of rimonabant are depression and GI symptoms.

Conclusions:

Rimonabant has significant effects on energy metabolism and food intake, probably mediated via its effects on GI motility.

Effect of high-oleic canola and flaxseed oils on energy expenditure and body composition in hypercholesterolemic subjects

OBJECTIVE

The fatty acid profile of dietary fats may contribute to its channelling toward oxidation versus storage, influencing energy and weight balance. Our objective was to compare the effects of diets enriched with high-oleic canola oil (HOCO), alone or blended with flaxseed oil (FXCO), on energy expenditure, substrate utilization, and body composition versus a typical Western diet (WD).

MATERIALS/METHODS

Using a randomized crossover design, 34 hypercholesterolemic subjects (n=22 females) consumed 3 controlled diets for 28 days containing ~49% energy from carbohydrate, 14% energy from protein, and 37% energy from fat, of which 70% of fat was provided by HOCO rich in oleic acid, FXCO rich in alpha-linolenic acid, or WD rich in saturated fat. Indirect calorimetry measured energy expenditure and substrate oxidation. Body composition was analyzed by dual-energy x-ray absorptiometry.

RESULT

After 28 days, resting and postprandial energy expenditure and substrate oxidation were not different after consumption of the HOCO or FXCO diets compared with a typical Western diet. No significant changes in body composition measures were observed between diets. However, the android-to-gynoid ratio tended to increase (P=.055) after the FXCO diet compared with the HOCO diet.

CONCLUSIONS

The data suggest that substituting a typical Western dietary fatty acid profile with HOCO or FXCO does not significantly modulate energy expenditure, substrate oxidation or body composition in hypercholesterolemic males and females.

Recent advancements in drug treatment of obesity

The prevalence of obesity is rising worldwide, with the U.K. having the highest prevalence in Europe. Obesity is associated with significant morbidity and has substantial healthcare implications, with current projections estimating that by 2030 obesity will cost the NHS approximately pounds 2 billion each year. Lifestyle modification remains the cornerstone of anti-obesity treatment, but drugs can be introduced as adjuncts to assist and maintain weight loss. Some 1.45 million obesity-related prescriptions were dispensed in 2009, highlighting the high demand for obesity pharmacotherapy. At present, the lipase inhibitor orlistat (Xenical) is the only UK-approved long-term medical therapy for obesity. Double-blind clinical trials have shown that orlistat significantly increases weight loss compared to placebo, but the array of adverse side effects associated with orlistat limits its tolerability. The need for more effective and better-tolerated anti-obesity medications is clear and six therapies have reached phase-III trials.

n-3 and n-6 polyunsaturated fatty acids differentially regulate adipose angiotensinogen and other inflammatory adipokines in part via NF-κB-dependent mechanisms

Excessive secretion of proinflammatory adipokines has been linked to metabolic disorders. We have previously documented anti-inflammatory effects of n-3 polyunsaturated fatty acids (n-3 PUFAs) in adipose tissue; however, the mechanisms by which these fatty acids regulate adipokine secretion remain unclear. Here, we determined differential effects of eicosapentaenoic acid (EPA, n-3 PUFA) vs. arachidonic acid (AA, n-6 PUFA) on expression and secretion of angiotensinogen (Agt), interleukin 6 (IL-6) and monocyte chemotactic protein (MCP-1) in 3T3-L1 adipocytes. While both PUFAs increased intracellular Agt protein and mRNA expression, Agt secretion into culture media was increased only by AA treatment, which in turn was prevented by co-treatment with EPA. At various AA/EPA ratios, increasing AA concentrations significantly increased secretion of the above three adipokines, whereas increasing EPA dose-dependently, while lowering AA, decreased their secretion. Moreover, IL-6 and MCP-1 were more significantly reduced by EPA treatment compared to Agt (IL-6>MCP>Agt). Next, we tested whether nuclear factor-κB (NF-κB), a major proinflammatory transcription factor, was involved in regulation of these adipokines by PUFAs. EPA significantly inhibited NF-κB activation compared to control or AA treatments. Moreover, EPA attenuated tumor necrosis factor-α-induced MCP-1 and further reduced its secretion in the presence of an NF-κB inhibitor. Taken together, we reported here novel beneficial effects of EPA in adipocytes. We demonstrated direct anti-inflammatory effects of EPA, which are at least in part due to the inhibitory effects of this n-3 PUFA on the NF-κB pathway in adipocytes. In conclusion, these studies further support beneficial effects of n-3 PUFAs in adipocyte inflammation and metabolic disorders.

The malnutrition of obesity: micronutrient deficiencies that promote diabetes

Obesity and diabetes are increasing in prevalence worldwide. Despite excessive dietary consumption, obese individuals have high rates of micronutrient deficiencies. Deficiencies of specific vitamins and minerals that play important roles in glucose metabolism and insulin signaling pathways may contribute to the development of diabetes in the obese population. This paper reviews the current evidence supporting this hypothesis.