Obesity: overview of an epidemic

More complex than you might think: Neural representations of food reward value in obesity

Obesity reached pandemic proportions and weight-loss treatments are mostly ineffective. The level of brain activity in the reward circuitry is proposed to be proportionate to the reward value of food stimuli, and stronger in people with obesity. However, empirical evidence is inconsistent. This may be due to the double-sided nature of high caloric palatable foods: at once highly palatable and high in calories (unhealthy). This study hypothesizes that, viewing high caloric palatable foods, a hedonic attentional focus compared to a health and a neutral attentional focus elicits more activity in reward-related brain regions, mostly in people with obesity. Moreover, caloric content and food palatability can be decoded from multivoxel patterns of activity most accurately in people with obesity and in the corresponding attentional focus. During one fMRI-session, attentional focus (hedonic, health, neutral) was manipulated using a one-back task with individually tailored food stimuli in 32 healthy-weight people and 29 people with obesity. Univariate analyses (p < 0.05, FWE-corrected) showed that brain activity was not different for palatable vs. unpalatable foods, nor for high vs. low caloric foods. Instead, this was higher in the hedonic compared to the health and neutral attentional focus. Multivariate analyses (MVPA) (p < 0.05, FDR-corrected) showed that palatability and caloric content could be decoded above chance level, independently of either BMI or attentional focus. Thus, brain activity to visual food stimuli is neither proportionate to the reward value (palatability and/or caloric content), nor significantly moderated by BMI. Instead, it depends on people's attentional focus, and may reflect motivational salience. Furthermore, food palatability and caloric content are represented as patterns of brain activity, independently of BMI and attentional focus. So, food reward value is reflected in patterns, not levels, of brain activity.

Expression of Recombinant Rat Secretable FNDC5 in Pichia Pastoris and Detection of Its Biological Activity

FNDC5 is the precursor of the myokine irisin proposed to exhibit favorable metabolic activity, including anti-obesity and anti-diabetes effects. The diversity of FNDC5 transcripts has been reported by several studies, but the role and existence of these transcripts are not well defined. In our previous study, a novel secretable FNDC5 (sFNDC5) isoform lacking the transmembrane region was found in rat INS-1 cells and multiple rat tissues. In the current study, we established a high-yield system for the expression and purification of sFNDC5 in Pichia pastoris, and functional investigations were undertaken using 3T3-L1 cells. We discovered that this new isoform has similar and even stronger biological functions than irisin, which may be due to its more complete structure without cleavage. Hence, we believe that sFNDC5, as the first identified readily secretable derivative, can better induce lipolysis and can potentially prevent obesity and related metabolic diseases.

Plant Extracts and Reactive Oxygen Species as Two Counteracting Agents with Anti- and Pro-Obesity Properties

Obesity is a complex disease of great public health significance worldwide: It entails several complications including diabetes mellitus type 2, cardiovascular dysfunction and hypertension, and its prevalence is increasing around the world. The pathogenesis of obesity is closely related to reactive oxygen species. The role of reactive oxygen species as regulatory factors in mitochondrial activity in obese subjects, molecules taking part in inflammation processes linked to excessive size and number of adipocytes, and as agents governing the energy balance in hypothalamus neurons has been examined. Phytotherapy is the traditional form of treating health problems using plant-derived medications. Some plant extracts are known to act as anti-obesity agents and have been screened in in vitro models based on the inhibition of lipid accumulation in 3T3-L1 cells and activity of pancreatic lipase methods and in in vivo high-fat diet-induced obesity rat/mouse models and human models. Plant products may be a good natural alternative for weight management and a source of numerous biologically-active chemicals, including antioxidant polyphenols that can counteract the oxidative stress associated with obesity. This review presents polyphenols as natural complementary therapy, and a good nutritional strategy, for treating obesity without serious side effects.

Wheat Flour, Enriched with γ-Oryzanol, Phytosterol, and Ferulic Acid, Alleviates Lipid and Glucose Metabolism in High-Fat-Fructose-Fed Rats

(1) Background: Modern dietary patterns with a high intake of fat and fructose, as well as refined carbohydrates, closely relate to lipid/glucose metabolic disorders. The main objective of this study is to provide new thoughts in designing functional food with some lipid/glucose metabolism regulating effects for obese people. (2) Methods: The alleviating abilities of γ-oryzanol, phytosterol or ferulic acid-enriched wheat flour on lipid/glucose metabolic dysfunction were evaluated in male SD rats induced by a high-fat-fructose diet. The underlying mechanisms were clarified using western blot. (3) Results: In an in vitro cell model, γ-oryzanol, phytosterol and ferulic acid regulate lipid/glucose metabolism by increasing the phosphorylation of AMPK and Akt, and PI3K expression, as well as decreasing expressions of DGAT1 and SCD. The in vivo study shows that ferulic acid and γ-oryzanol-enriched flours are beneficial for managing body weight, improving glucose metabolism, hyperlipidemia and hepatic lipid accumulation. Phytosterol-enriched flour exerted remarkable effects in regulating hyperinsulinemia, insulin resistance and hyperuricemia. Western blot analysis of proteins from liver samples reveals that these enriched flours alleviated hepatic lipid accumulation and insulin resistance through their elevation in the phosphorylation of AMPK and Akt. (4) Conclusions: Our study indicates that these enriched flours can serve as a health-promoting functional food to regulate obesity-related lipid/glucose metabolic dysfunction in rats.

Obesity and overweight in patients with hemophilia: Prevalence by age, clinical correlates, and impact on joint bleeding

BACKGROUND

The prevalence of obesity in patients with hemophilia (PWH) varies among different ethnicities, and its influence on joint bleeding and hemophilic arthropathy has not been studied in Taiwan population. We explored the prevalence and clinical correlates of obesity and the impact of body mass index (BMI) on annual joint bleeding rate (AJBR) and hemophilic arthropathy in PWH in Taiwan.

METHODS

We retrospectively collected clinical information on 140 severe/40 moderate PWH from 2006 to 2014. The patients' median age was 31.5 years, ranged from 6 to 73 years. Their BMI, 6 index joints score by Pettersson scoring, AJBR, and other clinical data were analyzed.

RESULTS

The prevalence of overweight and obesity by age group was 7.1% in PWH aged ≤10 years, and rapidly increased to 34.5% in PWH aged 11 to 18 years, 46.7% in PWH aged 18 to 29 years, 61.8% in PWH aged 30 to 39 years, 60.6% in PWH aged 40 to 49 years, and 48% in PWH aged ≥50 years, respectively. Two peak rates were 72.7% in PWH aged 35 to 44 years and 66.7% in PWH aged >65 years. Age, HCV infection, knee score, elbow score, and total 6 index joints scores were found to correlate positively with BMI. However, subtype and severity of hemophilia, ankle scores, HBV and HIV infection did not correlate with BMI. Finally, BMI was found to correlate positively with AJBR in both adult and pediatric PWH.

CONCLUSION

The prevalence of overweight and obesity in adolescent and adult PWH was higher than those in the general male population in Taiwan, which rapidly increased with age to peak in PWH aged 35 to 44 years and >65 years. High index joint score, with the exception of ankle scores, positively correlated with high BMI. Further, BMI and obesity also had positive correlation with AJBR in PWH. To our knowledge, this is the first study examining these associations in PWH in Taiwan.

Implicit process interventions in eating behaviour: a meta-analysis examining mediators and moderators

Dual-process models integrate deliberative and impulsive mental systems and predict dietary behaviours better than deliberative processes alone. Computerised tasks such as the Go/No-Go, Stop-Signal, Approach-Avoidance, and Evaluative Conditioning have been used as interventions to directly alter implicit biases. This meta-analysis examines the effects of these tasks on dietary behaviours, explores potential moderators of effectiveness, and examines implicit bias change as a proposed mechanism. Thirty randomised controlled trials testing implicit bias interventions (47 comparisons) were included in a random-effects meta-analysis, which indicated small cumulative effects on eating-related behavioural outcomes (g = -0.17, CI₉₅ = [-0.29; -0.05], p = .01) and implicit biases (g = -0.18, CI₉₅= [-0.34; -0.02], p = .02). Task type moderated these effects, with Go/No-Go tasks producing larger effects than other tasks. Effects of interventions on implicit biases were positively related to effects on eating behaviour (B = 0.42, CI₉₅= [0.02; 0.81], p = .03). Go/No-Go tasks seem to have most potential for altering dietary behaviours through implicit processes. While changes in implicit biases seem related to the effects of these interventions on dietary outcomes, more research should explore whether repeated exposure to implicit bias interventions may have any practical intervention value in real world settings.

Health Risk Behaviors after Disaster Exposure Among Older Adults

OBJECTIVE

The aim of this study was to examine the extent to which an exposure to disaster is associated with change in health behaviors.

METHODS

Federal disaster declarations were matched at the county-level to self-reported behaviors for participants in the Health and Retirement Study (HRS), 2000-2014. Multivariable logistic regression was used to evaluate the relationship between disaster and change in physical activity, body mass index (BMI), and cigarette smoking.

RESULTS

The sample included 20,671 individuals and 59,450 interviews; 1,451 unique disasters were declared in counties in which HRS respondents lived during the study period. Exposure to disaster was significantly associated with weight gain (unadjusted RRR=1.19; 95% CI, 1.11-1.27; adjusted RRR=1.21; 95% CI, 1.13-1.30). Vigorous physical activity was significantly lower among those who had experienced a disaster compared to those who had not (unadjusted OR=0.89; 95% CI, 0.84-0.95; adjusted OR=0.84; 95% CI, 0.79-0.89). No significant difference in cigarette smoking was found.

CONCLUSIONS

This study found an increase in weight gain and decrease in physical activity among older adults after disaster exposure. Adverse health behaviors such as these can contribute to functional decline among older adults.BellSA, ChoiH, LangaKM, IwashynaTJ. Health risk behaviors after disaster exposure among older adults. Prehosp Disaster Med. 2019;34(1):95-97.

Reverse shoulder arthroplasty in obese patients: analysis of functionality in the medium-term

INTRODUCTION

Obesity is an epidemic nowadays and this fact conditions results in orthopaedic surgery. Very few studies evaluates if obesity is a risk factor for reverse shoulder arthroplasty. The aim of this study is to confirm if there are differences with regard to the outcomes in patients undergoing reverse shoulder arthroplasty according to their body mass index (BMI).

MATERIALS AND METHODS

A total of 35 patients were enrolled in the study. Then divided into subpopulations according to their BMI and analyzed twice. First analysis set a division 30 of BMI and second set it in 35. ASES score, major complications, length of the hospital stay, radiolucent lines in components as well as scapular notching were assessed.

RESULTS

No major complications were described in our patients. No differences were found related to hospital stay, radiolucent lines or scapular notching. However, in the second analysis (BMI < 35 and ≥ 35) statistical differences were found regarding ASES score. Poorer functional outcomes were described in the type-II obese and morbidly obese population.

CONCLUSION

Functional outcomes of reverse shoulder arthroplasty are worse in patients with a BMI over 35.

Attachment anxiety is associated with a fear of becoming fat, which is mediated by binge eating

Background

Previous work demonstrated that individuals with higher levels of attachment anxiety are prone to increased binge eating (Alexander & Siegel, 2013). Given that our society rejects obese individuals and individuals with higher levels of attachment anxiety tend to be highly sensitive to rejection (Downey & Feldman, 1996), it follows that those with increased attachment anxiety may be especially fearful of becoming fat.

Methods

Undergraduate psychology students (n = 148) completed surveys measuring attachment, binge eating, and fear of becoming fat.

Results

The data demonstrate that attachment anxiety is positively associated with a fear of becoming fat (β = .30, p < .001) and binge eating mediates this relationship. In other words, binge eating underlies the fear of becoming fat.

Discussion

These findings contribute to a more refined understanding of binge eating which may create pathways for professionals to develop targeted interventions.

Obesity-Related Behaviors among Poor Adolescents and Young Adults: Is Social Position Associated with Risk Behaviors?

HighlightsDifferent measures of social position capture unique dimensions of relative rank among youth.Youth-specific measures of social position may be important in identifying the most at-risk for obesity.Lower social status youth are more likely to be at-risk for obesity-related behaviors compared to those with a higher rank. This cross-sectional study examines multiple dimensions of social position in relation to obesity-related behaviors in an adolescent and young adult population. In addition to using conventional measures of social position, including parental education and household expenditures, we explore the usefulness of three youth-specific measures of social position - community and society subjective social status and school dropout status. Data are taken from a 2004 house-to-house survey of urban households within the bottom 20th percentile of income distribution within seven states in Mexico. A total of 5,321 Mexican adolescents, aged 12-22 years, provided information on obesity-related behaviors (e.g., diet, physical activity, sedentary behavior) and indicators of subjective and objective social position. A parent in each household provided information on socioeconomic status of the parent and household. Ordinal logistic regressions are used to estimate the associations of parental, household and adolescent indicators of social position and obesity-related risk behaviors. Those adolescents with the highest odds of adopting obesity risk behaviors were the ones who perceived themselves as lower in social status in reference to their peer community and those who had dropped out of school. We found no significant associations between parental education or household expenditures and obesity-related risk behaviors. Immediate social factors in adolescents' lives may have a strong influence on their health-related behaviors. This study provides evidence for the usefulness of two particular measures, both of which are youth-specific. Adolescents and young adults who have dropped out of school and those with lower perceived relative social position within their community are more likely to be at-risk for obesity-related behaviors than those with higher relative social position. We conclude that youth-specific measures may be important in identifying the most at-risk among relatively homogeneous populations of youth.

Prevalence and relationship between gastrointestinal symptoms among individuals of different body mass index: A population-based study

BACKGROUND

Obesity has been identified as a potential risk factor for gastrointestinal (GI) symptoms, although the data from community samples remain sparse. We assess the associations between GI symptoms and obesity in a population-based sample of Australian adults.

METHOD

The prevalence of 26 GI symptoms was determined by a validated postal questionnaire which was sent to 5000 randomly selected residents. The response rate was 60%. GI symptoms were classified into six broader symptom groups based on the Rome II Criteria - abdominal pain, esophageal symptoms, dysmotility symptoms, diarrhea, vomiting, and constipation. Obesity was defined according to body mass index using self-reported height and weight.

RESULTS

The prevalence of obesity (BMI≥30kg/m(2)) was 25.1%; 36.1% were overweight. There were significant and positive univariate associations between obesity and abdominal pain (OR=1.75; 95% CI: 1.39-2.21), esophageal symptoms (OR=1.74; 95% CI: 1.36-2.22), dysmotility symptoms (OR=1.43; 95% CI: 1.16-1.77) and diarrhea (OR=2.01; 95% CI: 1.65-2.45). The adjustment for socioeconomic characteristics and eating behaviors had minimal effect on the associations for abdominal pain (OR=1.34; 95% CI: 1.01-1.79), esophageal symptoms (OR=1.35; 95% CI: 1.03-1.78), and diarrhea (OR=1.86; 95% CI: 1.49-2.31); however, the association between obesity and dysmotility symptoms became non-significant. Obesity was not related to constipation.

CONCLUSION

Obesity is an independent risk factor for abdominal pain, esophageal symptoms and diarrhea, but is not associated with dysmotility symptoms or constipation.

Worry or craving? A selective review of evidence for food-related attention biases in obese individuals, eating-disorder patients, restrained eaters and healthy samples

Living in an ‘obesogenic’ environment poses a serious challenge for weight maintenance. However, many people are able to maintain a healthy weight indicating that not everybody is equally susceptible to the temptations of this food environment. The way in which someone perceives and reacts to food cues, that is, cognitive processes, could underlie differences in susceptibility. An attention bias for food could be such a cognitive factor that contributes to overeating. However, an attention bias for food has also been implicated with restrained eating and eating-disorder symptomatology. The primary aim of the present review was to determine whether an attention bias for food is specifically related to obesity while also reviewing evidence for attention biases in eating-disorder patients, restrained eaters and healthy-weight individuals. Another aim was to systematically examine how selective attention for food relates (causally) to eating behaviour. Current empirical evidence on attention bias for food within obese samples, eating-disorder patients, and, even though to a lesser extent, in restrained eaters is contradictory. However, present experimental studies provide relatively consistent evidence that an attention bias for food contributes to subsequent food intake. This review highlights the need to distinguish not only between different (temporal) attention bias components, but also to take different motivations (craving v. worry) and their impact on attentional processing into account. Overall, the current state of research suggests that biased attention could be one important cognitive mechanism by which the food environment tempts us into overeating.

Relationship between Body Mass Index, Blood Pressure, and Visual Acuity in Residents of Esan West Local Government Area of Edo State, Nigeria

Aim. To study the relationship between body mass index (BMI) and blood pressure (BP) on visual acuity among apparently healthy residents of Ekpoma, Esan West Local Government Area of Edo State, Nigeria. Methodology. This is a cross-sectional descriptive study among 225 subjects (ages of 18–35 years) from whom BP, body weight, and height were collected. Visual acuity was measured using the Snellen chart following standard procedures of number of letters seen at 6-metre distance. The data were then analyzed using SPSS version 17. Results. The sampled population consists of 112 male and 113 female (mean age 31.72±14.2 years). Majority (180) of the respondents had normal visual acuity. However, compared with the respondents with normal BMI (R19.61±1.5; L19.67±1.70), visual acuity of underweight (R18.53±2.30; L18.53±2.70) and obese (R15.68±4.79; L17.73±1.70) were more deviated. Similarly, compared with respondent with normal BP (120–125/80–85 mmHg; R18.00±2.53; L18.07±3.11), hypotensive (R15.5±7.35; L15.00±10.20), and hypertensive (R15.01±21.25; L15.00±11.91) respondents had deviated visual acuity. Conclusion. Abnormal body weight (underweight and obese) and BP (hypotension and hypertension) have potential negative impacts on visual acuity. Based on the observed relationship between weights, BP, and visual acuity, eye examinations can be included as regular screening exercise for abnormal BMI and BP conditions.

Looking at food in sad mood: do attention biases lead emotional eaters into overeating after a negative mood induction?

BACKGROUND

Emotional eating is associated with overeating and the development of obesity. Yet, empirical evidence for individual (trait) differences in emotional eating and cognitive mechanisms that contribute to eating during sad mood remain equivocal.

AIM

The aim of this study was to test if attention bias for food moderates the effect of self-reported emotional eating during sad mood (vs neutral mood) on actual food intake. It was expected that emotional eating is predictive of elevated attention for food and higher food intake after an experimentally induced sad mood and that attentional maintenance on food predicts food intake during a sad versus a neutral mood.

METHOD

Participants (N = 85) were randomly assigned to one of the two experimental mood induction conditions (sad/neutral). Attentional biases for high caloric foods were measured by eye tracking during a visual probe task with pictorial food and neutral stimuli. Self-reported emotional eating was assessed with the Dutch Eating Behavior Questionnaire (DEBQ) and ad libitum food intake was tested by a disguised food offer.

RESULTS

Hierarchical multivariate regression modeling showed that self-reported emotional eating did not account for changes in attention allocation for food or food intake in either condition. Yet, attention maintenance on food cues was significantly related to increased intake specifically in the neutral condition, but not in the sad mood condition.

DISCUSSION

The current findings show that self-reported emotional eating (based on the DEBQ) might not validly predict who overeats when sad, at least not in a laboratory setting with healthy women. Results further suggest that attention maintenance on food relates to eating motivation when in a neutral affective state, and might therefore be a cognitive mechanism contributing to increased food intake in general, but maybe not during sad mood.

Normalisation and Stigmatisation of Obesity in UK Newspapers: a Visual Content Analysis

Obesity represents a major and growing global public health concern. The mass media play an important role in shaping public understandings of health, and obesity attracts much media coverage. This study offers the first content analysis of photographs illustrating UK newspaper articles about obesity. The researchers studied 119 articles and images from five major national newspapers. Researchers coded the manifest content of each image and article and used a graphical scale to estimate the body size of each image subject. Data were analysed with regard to the concepts of the normalisation and stigmatisation of obesity. Articles' descriptions of subjects' body sizes were often found to differ from coders' estimates, and subjects described as obese tended to represent the higher values of the obese BMI range, differing from the distribution of BMI values of obese adults in the UK. Researchers identified a tendency for image subjects described as overweight or obese to be depicted in stereotypical ways that could reinforce stigma. These findings are interpreted as illustrations of how newspaper portrayals of obesity may contribute to societal normalisation and the stigmatisation of obesity, two forces that threaten to harm obese individuals and undermine public health efforts to reverse trends in obesity.

Diet-induced obesity reduces the responsiveness of the peripheral taste receptor cells

Introduction

Obesity is a growing epidemic that causes many serious health related complications. While the causes of obesity are complex, there is conclusive evidence that overconsumption coupled with a sedentary lifestyle is the primary cause of this medical condition. Dietary consumption is controlled by appetite which is in turn regulated by multiple neuronal systems, including the taste system. However, the relationship between taste and obesity has not been well defined. Growing evidence suggests that taste perception in the brain is altered in obese animals and humans, however no studies have determined if there are altered taste responses in the peripheral taste receptor cells, which is the initiation site for the detection and perception of taste stimuli.

Methodology/Principal Findings

In this study, we used C57Bl/6 mice which readily become obese when placed on a high fat diet. After ten weeks on the high fat diet, we used calcium imaging to measure how taste-evoked calcium signals were affected in the obese mice. We found that significantly fewer taste receptor cells were responsive to some appetitive taste stimuli while the numbers of taste cells that were sensitive to aversive taste stimuli did not change. Properties of the taste-evoked calcium signals were also significantly altered in the obese mice. Behavioral analyses found that mice on the high fat diet had reduced ability to detect some taste stimuli compared to their littermate controls.

Conclusions/Significance

Our findings demonstrate that diet-induced obesity significantly influences peripheral taste receptor cell signals which likely leads to changes in the central taste system and may cause altered taste perception.

Perceived hunger mediates the relationship between attachment anxiety and emotional eating

Eating is an inherently emotional activity and the attachment system is an emotion regulation system. Individuals with attachment insecurity have less interoceptive awareness and difficulty regulating emotion. Insecurely attached individuals may eat emotionally because they misinterpret internal hunger cues, (i.e. think they are hungry when they are experiencing some other internal, attachment-related state). The current study found a positive association between attachment anxiety and emotional eating. This relationship was mediated by perceived hunger.

Adherence to clusters of health behaviors and successful aging

OBJECTIVE

Analyses examine the extent to which adherence to recommendations regarding health behaviors cluster among older adults, whether people who adhere to multiple health behaviors are more likely to age successfully than those who adhere to fewer health behaviors, and whether some health behavior clusters are more closely associated with successful aging than others.

METHOD

Cross-sectional data were collected using structured telephone interviews from 5,688 persons aged 50 to 74 living in New Jersey.

RESULTS

Prevalence odds ratio analyses indicated that differential cluster patterns exist. Logistic regression revealed that as the number of adherent behaviors increased so did the likelihood of aging successfully and that adherence to some health behavior clusters was more closely associated with successful aging than adherence to others.

DISCUSSION

Although adherence to more health behaviors was associated with a greater likelihood of successful aging, it is possible to age successfully by adhering to specific clusters of health behaviors.

Overweight and obesity in hemophilia: a systematic review of the literature

CONTEXT

As life expectancy in individuals with congenital hemophilia approaches that of the general population, we hypothesize that public health risks, including overweight and obesity, also follow a similar trend.

EVIDENCE ACQUISITION

A search of the literature included terms relating to overweight, sequelae of being overweight, and hemophilia. Studies were included if they reported the frequency or clinical significance of known complications of overweight and obesity, including musculoskeletal disease, aerobic capacity, cardiovascular disease, diabetes, hyperlipidemia, decreased quality of life, and change in pharmacokinetics of infused clotting factor in hemophilia. Recommendations from medical organizations were searched for preventive and management strategies applicable to this population.

EVIDENCE SYNTHESIS

Overweight and obesity are now more prevalent in the hemophilia population than previous generations, with rates similar to and, in certain subsets even higher, than that of the general population. Increased BMI leads to limitations in joint range of motion in the general population and even more so in persons with hemophilia.

CONCLUSIONS

Overweight and obesity in hemophilia are an increasing problem. Simple steps can be taken to encourage patients to decrease caloric intake and increase physical activity. Prevention and management of overweight, obesity, and their sequelae must be addressed in clinical practice in order to maximize the overall health of the hemophilia population.

Knowledge, attitudes, and beliefs about nutrition and childhood overweight among WIC participants

This study assessed knowledge, attitudes, and beliefs about nutrition, physical activity, and health risks related to childhood overweight among Women, Infants, and Children participants. Most (n = 165) were knowledgeable about causes/health risks of overweight (90%). The belief that "some people are born big or thin . . . " varied by education level (P < 0.05). Concerning activity, many (white non-Hispanic, 53%; African-American 69%) reported their children spending 2 to 3 hours per day watching television and playing video games, with 10% white non-Hispanic and 21% of African-American reporting 4 hours or more (P < 0.05). Beliefs related to the risk of overweight and activity level of the children differed among ethnic groups.

Parabrachial coding of sapid sucrose: relevance to reward and obesity

Cumulative evidence in rats suggests that the pontine parabrachial nuclei (PBN) are necessary for assigning hedonic value to taste stimuli. In a series of studies, our laboratory has investigated the parabrachial coding of sapid sucrose in normal and obese rats. First, using chronic microdialysis, we demonstrated that sucrose intake increases dopamine release in the nucleus accumbens, an effect that is dependent on oral stimulation and on concentration. The dopamine response was independent of the thalamocortical gustatory system but was blunted substantially by lesions of the PBN. Similar lesions of the PBN but not the thalamic taste relay diminished cFos activation in the nucleus accumbens caused by sucrose ingestion. Recent single-neuron recording studies have demonstrated that processing of sucrose-evoked activity in the PBN is altered in Otsuka Long Evans Tokushima Fatty (OLETF) rats, which develop obesity due to chronic overeating and express increased avidity to sweet. Compared with lean controls, taste neurons in OLETF rats had reduced overall sensitivity to sucrose and altered concentration responses, with decreased responses to lower concentrations and augmented responses to higher concentrations. The decreased sensitivity to sucrose was specific to NaCl-best neurons that also responded to sucrose, but the concentration effects were carried by the sucrose-specific neurons. Collectively, these findings support the hypothesis that the PBN enables taste stimuli to engage the reward system and, in doing so, influences food intake and body weight regulation. Obesity, in turn, may further alter the gustatory code via forebrain connections to the taste relays or hormonal changes consequent to weight gain.

Correlates of video game screen time among males: body mass, physical activity, and other media use

This study examined the correlations between media use, body mass variables, and physical activity among 116 male undergraduates (white n=106; African American n=5, Latin American n=1, Asian American n=2, and 2 others). Length of video game play during one sitting was positively related to body mass index (BMI; r=.27, p<.01) and negatively correlated with frequency of exercise (r=-.21, p<.05) and days of walking (r=-.22, p<.05). Frequency of video game play was negatively correlated with length of exercising (r=-.21, p<.05). Years of video game play was negatively correlated with length of exercise (r=-.21, p<.05). These results were stronger among those who play online games. Hierarchical regression analyses indicated that video game use predicted BMI, accounting for 6.9% of the variance. The implications of the results are discussed.

Adult weight management: translating research and guidelines into practice

PURPOSE

To provide a practical approach to managing overweight and obese adult patients based on data from research and recommendations from established guidelines.

DATA SOURCES

Comprehensive review articles and original research articles identified through Medline and the Cumulative Index to Nursing and Allied Health Literature (CINAHL).

CONCLUSIONS

There is a great deal of research being conducted on new ways to treat obesity; however, despite all this new information, many primary care providers continue to report that they do not address weight or weight control strategies with their patients. Reasons include too little time, not enough training, lack of financial incentive, and failure to believe that patients can be successful.

IMPLICATIONS FOR PRACTICE

Weight management essentially comes down to one key concept: negative energy balance (fewer calories in and/or more calories out). Patients can be taught how to achieve a negative energy balance by using a food/exercise diary to track their daily caloric goal to achieve a 1-2 pound weight loss per week. Nurse practitioners (NPs) can implement safe and effective weight management plans for their patients by teaching them how to self-monitor, eat healthy, and exercise. This method is similar to what NPs commonly use for patients with diabetes mellitus.

Association of the common genetic variant upstream of INSIG2 gene with obesity related phenotypes in Chinese children and adolescents

OBJECTIVE

To study the association between the rs7566605 variant of INSIG2 and obesity-related phenotypes in Chinese children and adolescents.

METHODS

The study sample consisted of two independent cohorts of Chinese children and adolescents. Anthropometric indices, lipids, blood pressure, fasting glucose, insulin and percentage of fat mass were determined. PCR with restriction fragment length polymorphism analysis was performed for genotyping the rs7566605 variant.

RESULTS

In each of the two independent cohorts, no significant association was observed between rs7566605 and obesity under additive, dominant or recessive model. We also did not detect any difference in the genotype frequency between all the obese children and controls. Furthermore, we did not find evidence of an association between body composition indices and metabolic phenotypes in all children. However, the triglyceride level of CC homozygotes was significantly higher than that of GG+GC genotypes in obese children (P=0.022). Additionally, we observed a non-significant trend of severe obesity in a post-hoc test.

CONCLUSION

INSIG2 rs7566605 variant is not associated Chinese childhood obesity in two independent cohorts. Further study is needed to verify the effect of rs7566605 on triglyceride in obese children.

Rapid increases in obesity in Jamaica, compared to Nigeria and the United States

Background

Weight gain in adulthood is now common in many populations, ranging from modest gains in developing countries to a substantial percentage of body weight in some Western societies. To examine the rate of change across the spectrum of low to high-income countries we compared rates of weight change in samples drawn from three countries, Nigeria, Jamaica and the United States.

Methods

Population samples from Nigeria (n = 1,242), Jamaica (n = 1,409), and the US (n = 809) were selected during the period 1995–1999 in adults over the age of 19; participation rates in the original survey were 96%, 60%, and 60%, respectively. Weight in (kg) was measured on 3 different occasions, ending in 2005. Multi-level regression models were used to estimate weight change over time and pattern-mixture models were applied to assess the potential effect of missing data on estimates of the model parameters.

Results

The unadjusted weight gain rate (standard error) was 0.34(0.06), 1.26(0.12), 0.34(0.19) kg/year among men and 0.43(0.06), 1.28(0.10), 0.40(0.15) kg/year among women in Nigeria, Jamaica, US, respectively. Regression-adjusted weight change rates were significantly different across country, sex, and baseline BMI. Adjusted weight gain in Nigeria, Jamaica and US was 0.31(0.05), 1.37(.04), and 0.52(0.05) kg/year respectively. Women in Nigeria and the US had higher weight gains than men, with the converse observed among Jamaicans. The obese experienced weight loss across all three samples, whereas the normal weight (BMI < 25) had significant weight gains. Missing data patterns had an effect on the rates of weight change.

Conclusion

Weight change in sample cohorts from a middle-income country was greater than in cohorts from either of the low- or high-income countries. The steep trajectory of weight gain in Jamaica, relative to Nigeria and the US, is most likely attributable to the accelerating effects of the cultural and behavioral shifts which have come to bear on transitional societies.

The relationship between obesity and the age at which hip and knee replacement is undertaken

We audited the relationship between obesity and the age at which hip and knee replacement was undertaken at our centre. The database was analysed for age, the Oxford hip or knee score and the body mass index (BMI) at the time of surgery. In total, 1369 patients were studied, 1025 treated by hip replacement and 344 by knee replacement. The patients were divided into five groups based on their BMI (normal, overweight, moderately obese, severely obese and morbidly obese).

The difference in the mean Oxford score at surgery was not statistically significant between the groups (p > 0.05). For those undergoing hip replacement, the mean age of the morbidly obese patients was ten years less than that of those with a normal BMI. For those treated by knee replacement, the difference was 13 years. The age at surgery fell significantly for those with a BMI > 35 kg/m2 for both hip and knee replacement (p > 0.05). This association was stronger for patients treated by knee than by hip replacement.

Obese OLETF rats exhibit increased operant performance for palatable sucrose solutions and differential sensitivity to D2 receptor antagonism

CCK-1-receptor-deficient Otsuka Long-Evans Tokushima fatty (OLETF) rats are hyperphagic and exhibit a greater preference for sucrose compared with lean controls [Long-Evans Tokushima Otsuka (LETO)]. To directly assess motivation to work for sucrose reward in this model of obesity and type 2 diabetes, we examined the operant performance of OLETF rats at nondiabetic and prediabetic stages (14 and 24 wk of age, respectively) on fixed-ratio (FR) and progressive-ratio (PR) schedules of reinforcement. To evaluate the involvement of dopamine systems, the effects of the D1 receptor antagonist SCH23390 (100 and 200 nmol/kg ip) and the D2 receptor antagonist raclopride (200 and 400 nmol/kg ip), were also tested on PR responding for sucrose. Compared with age-matched LETO rats, 14-wk-old OLETF rats emitted more licks on the "active" empty spout operant on the FR-10 schedule of reinforcement to obtain 0.01 M and 0.3 M sucrose and completed higher ratio requirements on the PR schedule to gain access to 0.3 M and 1.0 M sucrose. At 24 wk, this effect was limited to 1.0 M sucrose. Both antagonists were potent in reducing operant responding to 0.3 M sucrose in both strains at both ages, and there was no strain effect to SCH23390 at either age. OLETF rats, on the other hand, showed an increased sensitivity to the higher dose of raclopride, resulting in reduced responding to sucrose reinforcement at 24 wk. Taken together, these findings provide the first direct evidence for an increased motivation for sucrose reward in the OLETF rats and suggest altered D2 receptor regulation with the progression of obesity and prediabetes.

Weight loss before gastric bypass: feasibility and effect on postoperative weight loss and weight loss maintenance

BACKGROUND

This study was performed at a tertiary care university hospital. We hypothesized that weight loss before laparoscopic Roux-en-Y gastric bypass (LRYGB) is feasible, does not diminish the expected postoperative weight loss, and might enhance overall weight loss and maintenance.

METHODS

A population of 351 consecutive patients, who had undergone LRYGB, was divided into 4 groups depending on the percentage of body weight loss achieved before surgery (group 1, none or gain; group 2, <5%; group 3, 5-10%; and group 4, >10%). Data were collected regarding the demographics, body mass index (BMI) change, and excess weight loss and analyzed by analysis of variance and Fisher's exact test at the alpha = 0.05 level.

RESULTS

All groups were demographically similar in age and were predominantly women. The maximal follow-up was 36 months. Groups 3 and 4 had significantly greater initial excess weight and BMI (P <.05) but these became similar after the preoperative weight loss. Most patients (74%) were able to lose weight before surgery, with 36% losing >5% body weight. Preoperative weight loss did not decrease the magnitude of the expected postoperative weight loss. Patients who lost weight preoperatively demonstrated more excess weight loss and BMI change (from their initial weight) that was sustained far into the postoperative period and reached statistical significance at several points (P <.05).

CONCLUSION

The results of this study have demonstrated that obese patients are capable of losing weight before LRYGB and that this weight loss does not negatively affect their expected postoperative weight loss. Furthermore, preoperative weight loss combined with LRYGB might result in better long-term excess weight loss and BMI change than surgery alone.

Obesity and eye diseases

The prevalence of obesity has reached epidemic proportions in many countries. Although its impact on overall health is well documented, less is known about the ocular manifestations of obesity. Among different eye diseases, obesity has been linked with age-related cataract, glaucoma, age-related maculopathy, and diabetic retinopathy. Numerous population-based and prospective studies support an association between obesity and risk of age-related cataract. However, the nature and strength of these associations, particularly with the different cataract subtypes, remains to be determined. There is strong evidence that obesity is associated with elevated intraocular pressure, but there is no convincing data to support a more direct association between obesity and glaucomatous optic neuropathy. Studies to date have not found a consistent pattern of association between obesity and risk of age-related maculopathy or diabetic retinopathy. Thus, although obesity may be a risk factor for many ocular conditions, the present literature is inadequate to establish any convincing associations. Furthermore, whether weight loss reduces the risk of eye diseases remains unresolved. Because of the potential public health impact of obesity, there is a greater need to understand its ocular effects.

Obesity increases the likelihood of total joint replacement surgery among younger adults

We conducted a retrospective review of medical charts of patients, aged 18 to 59 years old, who underwent either a total knee replacement (TKR) or total hip replacement (THR) from January 2002 to December 2004. Of the 204 study subjects, 52% had a TKR while 48% had a THR. Obesity was significantly associated with the need for a TKR or THR when comparing the study group to adults of similar age in the general population (P< 0.0001). Seventy-two percent (146) of the study group was obese and 21% (42) overweight (BMI 25.0 to 29.9 kg/m(2)) compared to only 26% (596) obese and 34% (732) overweight in the general population. Patients undergoing a TKR were significantly more likely to be obese (BMI>30 kg/m(2)) than those having a THR, 83% (89) compared to 59% (57) (P< .0006). Our findings support those previously observed in the elderly population. Primary and secondary prevention programs aimed at reducing obesity are strongly recommended.

Intraventricular insulin and leptin reduce food intake and body weight in C57BL/6J mice

As the incidence of obesity continues to increase, adequate animal models acquire increased importance for the investigation of energy homeostatic mechanisms. Understanding the central mechanism of action of the adiposity hormones, insulin and leptin, has become particularly important as researchers examine ways to treat or prevent obesity. Although the intra-3rd-ventricular (i3vt) administration of insulin reduces food intake in several species, its effects on food intake and body weight have not been previously been assessed in mice. Male C57BL/6J mice were administered insulin i3vt (0.05, 0.1 or 0.4 microU) or leptin i3vt (5 microg/1 microl) as a positive control. As it occurs in other species, i3vt insulin dose-dependently reduced 24-h food intake and body weight, and increased hypothalamic proopiomelanocortin (POMC) mRNA. Hence, genetic manipulations that influence brain insulin sensitivity in mice can now more easily be integrated with the broader literature on energy homeostasis.

Leptin regulates olfactory-mediated behavior in ob/ob mice

We have investigated olfactory-mediated pre-ingestive behavior in leptin (ob/ob) and leptin receptor (db/db) mutant mice compared to age- and gender-matched wild-type (wt) mice. Olfactory-mediated behavior was tested using a buried food paradigm 5 times/day at 2-h intervals for 6 days. Mean food-finding times of ob/ob and db/db mice were approximately 10 times shorter than those of wt mice. To test the effect of leptin replacement in ob/ob mice, leptin (1 or 5 microg/g body weight in sterile saline) or carrier was injected i.p. once daily prior to testing. Mean food finding times in ob/ob mice injected with carrier or with 1 microg/g leptin were similar and were 2-3 times faster than in wt mice. Mean food finding times in ob/ob mice injected with 5 microg/g leptin tripled compared to carrier-injected ob/ob mice and were of the same order of magnitude as those of wt mice, suggesting functional leptin replacement. A 3-factor repeated measures ANOVA demonstrated significant differences between the 6 cohorts (P = 0.0001), food finding times (P< or = 0.0001), and cohort by day interaction (P< or = 0.0001). Post hoc tests suggested that the ob/ob+5 mug/g leptin cohort performed more like the wt cohort in the food-finding test than like the ob/ob or ob/ob+carrier cohort. Potential local sites of leptin production and action were identified with immunohistochemistry and in situ hybridization in epithelial and gland cells of the olfactory and nasal mucosae. Our results strongly suggest that leptin acting through leptin receptors modulates olfactory-mediated pre-ingestive behavior.

Altered taste sensitivity in obese, prediabetic OLETF rats lacking CCK-1 receptors

Otsuka Long-Evans Tokushima fatty (OLETF) rats lack the CCK-1 receptor, are hyperphagic, progressively become obese, and develop type-2 diabetes. We recently demonstrated an increased preference for both real and sham feeding of sucrose in this strain, suggesting altered orosensory sensitivity. To investigate taste functions, we used an automated gustometer with 10-s access to different concentrations of various sapid stimuli. Tests were repeated at 10 and 18 wk of age to assess the early and advanced stages of prediabetes, respectively. Compared with age-matched, nonmutant controls, the OLETF rats showed higher avidity for sucrose at both ages. This difference increased as a function of age and tastant concentration. An exaggerated response also occurred for saccharin, alanine, and fructose, but not for Polycose. Similarly, OLETF rats consumed monosodium-glutamate more at the lower concentrations compared with controls, an effect that age also accentuated. In contrast, there was no statistical strain or age differences in responses to NaCl, MgCl2, citric acid, quinine-HCl, and the trigeminal stimulus capsaicin. These findings demonstrate that compared with controls, OLETF rats differ in their gustatory functions with an overall augmented sensitivity for sweet that progresses during prediabetes. This effect explains their overconsumption of sweet solutions and may contribute to the overall hyperphagia and obesity in this strain.