Design characteristics of worksite environmental interventions for obesity prevention

Objective: This paper describes the design characteristics of the National Heart, Lung, and Blood Institute (NHLBI)‐funded studies that are testing innovative environmental interventions for weight control and obesity prevention at worksites. Research Methods and Procedures: Seven separate studies that have a total of 114 worksites (～48,000 employees) across studies are being conducted. The worksite settings include hotels, hospitals, manufacturing facilities, businesses, schools, and bus garages located across the U.S. Each study uses its own conceptual model drawn from the literature and includes the socio‐ecological model for health promotion, the epidemiological triad, and those integrating organizational and social contexts. The interventions, which are offered to all employees, include environmental‐ and individual‐level approaches to improve physical activity and promote healthful eating practices. Environmental strategies include reducing portion sizes, modifying cafeteria recipes to lower their fat contents, and increasing the accessibility of fitness equipment at the workplace. Across all seven studies about 48% (N = 23,000) of the population is randomly selected for measurements. The primary outcome measure is change in BMI or body weight after two years of intervention. Secondary measures include waist circumference, objective, and self‐report measures of physical activity, dietary intake, changes in vending machines and cafeteria food offerings, work productivity, healthcare use, and return on investment. Discussion: The results of these studies could have important implications for the design and implementation of worksite overweight and obesity control programs.     

Sexual Functioning and Obesity: A Review

We review the literature on the relationship between obesity and sexual functioning. Eleven population‐based studies, 20 cross‐sectional non‐population‐based studies, and 16 weight loss studies are reviewed. The consistency of findings suggests that the relationship between obesity and reduced sexual functioning is robust, despite diverse methods, instruments, and settings. In most population‐based studies, erectile dysfunction (ED) is more common among obese men than among men of recommended weight. Studies of patients in clinical settings often include individuals with higher degrees of obesity, with most studies showing a relationship between obesity and lower levels of sexual functioning, especially ED. The few studies that include both genders generally report more problems among women. Most studies of patients with comorbidities associated with obesity also find an association between obesity and reduced sexual functioning. Most weight loss studies demonstrate improvement in sexual functioning concurrent with weight reduction despite varying study designs, weight loss methods, and follow‐up periods. We recommend that future studies (i) investigate differences and similarities between men and women with respect to obesity and sexual functioning, (ii) use instruments that go beyond the assessment of sexual dysfunction to include additional concepts such as sexual satisfaction, interest, and arousal and, (iii) assess how and the degree to which obese individuals are affected by sexual difficulties. Given the high prevalence of obesity and the inverse association between body mass and sexual functioning, we also recommend that sexual functioning should be more fully addressed by clinicians, both in general practice and in weight loss programs.     

Attitudes to publicly funded obesity treatment and prevention

The aim of this study was to investigate the Danish public's support for publicly funded obesity treatment and prevention. It was also examined whether levels of support could be explained by dislike of obese people and/or the belief that those who are obese are personally responsible for their condition. A representative survey of members of the Danish public (N = 1,141) was conducted using a web-based questionnaire. The survey was designed to assess attitudes to public funding for obesity-related health care, and to investigate the impact, on those attitudes, of dislike of obese people, the perceived controllability of obesity, self-reported BMI, and additional attitudinal and socio-demographic characteristics. Public funding of some obesity treatments, such as weight-loss surgery, attracted only limited public support. A majority of the Danish public did support "softer" treatment interventions and preventive initiatives. Attitudes to the treatment of obesity were clearly best predicted by the belief that individuals are personally responsible for their own obesity. Dislike of obese persons had no direct effect on the preference for collective treatment initiatives and only a small effect on support for publicly funded obesity prevention. The high level of disapproval for publicly funded obesity treatment should be cause for concern for decision makers aiming to ensure equal access to health care. Since it is the belief that obese people are personally responsible which explains this disapproval, strategies for challenging public opinion on this issue are discussed.     

Adult Obesity and Office‐based Quality of Care in the United States

Nationally representative data on the quality of care for obese patients in US‐ambulatory care settings are limited. We conducted a cross‐sectional analysis of the 2005 and 2006 National Ambulatory Medical Care Survey (NAMCS). We examined obesity screening, diagnosis, and counseling during adult visits and associations with patient and provider characteristics. We also assessed performance on 15 previously published ambulatory quality indicators for obese vs. normal/overweight patients. Nearly 50% (95% confidence interval (CI): 46–54%) of visits lacked complete height and weight data needed to screen for obesity using BMI. Of visits by patients with clinical obesity (BMI ≥30.0 kg/m²), 70% (66–74%) were not diagnosed and 63% (59–68%) received no counseling for diet, exercise, or weight reduction. The percentage of visits not being screened (48%), diagnosed (66%), or counseled (54%) for obesity was also notably higher than expected even for patients with known obesity comorbidities. Performance (defined as the percentage of applicable visits receiving appropriate care) on the quality indicators was suboptimal overall. In particular, performance was no better than 50% for eight quality indicators, which are all related to the prevention and treatment of obesity comorbidities, e.g., coronary artery disease, hypertension, hyperlipidemia, asthma, and depression. Performance did not differ by weight status for any of the 15 quality indicators; however, poorer performance was consistently associated with lack of height and weight measurements. In conclusion, many opportunities are missed for obesity screening and diagnosis, as well as for the prevention and treatment of obesity comorbidities, in office‐based practices across the United States, regardless of patient and provider characteristics.     

Economic Evaluation of a Community‐based Obesity Prevention Program in Children: The APPLE Project

Effective strategies are urgently required to reduce the prevalence of obesity during growth. Determining which strategies are most successful should also include analysis of their relative costs. To date, few obesity prevention studies in children have reported data concerning cost‐effectiveness. The aim of this study was to assess the costs and health benefits of implementing the APPLE (A Pilot Program for Lifestyle and Exercise) project, a 2‐year controlled community‐based obesity prevention initiative utilizing activity coordinators (ACs) in schools and nutrition promotion in New Zealand children (5–12 years). The marginal costs of the project in 2006 prices were estimated and compared with the kilograms (kg) of weight‐gain prevented for children in the intervention relative to the control arm. The children's health‐related quality of life (HRQoL) was also measured using the Health Utilities Index (HUI). The total project cost was NZ$357,490, or NZ$1,281 per intervention child for 2 years (NZ$1 = US$0.67 = UK£0.35 = EUR €0.52). Weight z‐score was reduced by 0.18 (0.13, 0.22) units at 2 years and 0.17 (0.11, 0.23) units at 4 years in intervention relative to control children. Mean HUI values did not differ between intervention and control participants. The reduction in weight z‐score observed is equivalent to 2.0 kg of weight‐gain prevented at 15 years of age. The relatively simple intervention approach employed by the APPLE project was successful in significantly reducing the rate of excessive weight gain in children, with implementation costs of NZ$664–1,708 per kg of weight‐gain prevented over 4 years.     

Research challenges to improve the management and conservation of subtropical reefs to tackle climate change threats

This paper reports on a workshop conducted in Australia in 2010, entitled ‘Management, Conservation, and Scientific Challenges on Subtropical Reefs under Climate Change’. The workshop brought together 26 experts actively involved in the science and management of subtropical reefs. Its primary aim was to identify the areas of research that need to be most urgently addressed to improve the decision‐making framework for managers of subtropical reefs. The main findings of the workshop were a sustainable subtropical reefs declaration that highlights seven research priorities for subtropical reefs. These are to (i) conduct research and management activities across local government, state and bioregion borders; (ii) understand natural variability of environmental conditions; (iii) quantify socio‐economic factors and ecosystem services; (iv) benchmark cross‐realm connectivity; (v) know marine population connectivity; (vi) habitat mapping and ecological research; and (v) determine refugia. These findings are hoped to form a basis for focussing research efforts, leveraging funds and assisting managers with allocation of resources.     

Interventions to prevent or treat obesity in preschool children: a review of evaluated programs

Objective: To identify effective programs to prevent or treat overweight among 2‐ to <6‐year‐old children. Research Methods and Procedures: We searched six databases to identify evaluated intervention programs assessing changes in weight status or body fat and systematically summarized study attributes and outcomes. Results: Four of the seven studies (two intervention, two prevention) documented significant reductions in weight status or body fat. Among these, three sustained reductions at 1 or 2 years after program initiation, three incorporated a framework/theory, two actively and one passively involved parents, three included multicomponent strategies, and all four monitored behavioral changes. Of the three (prevention) studies that did not show reduction in weight or fat status, all performed assessments between 4 and 9 months after program initiation, and one used a multicomponent strategy. Other significant changes reported were reductions in television viewing, cholesterol, and parental restriction of child feeding. Discussion: The paucity of studies limits our ability to generalize findings. Among the available studies, multicomponent programs with 1‐ to 2‐year follow‐up in clinics or child care settings were successful in their impact on weight; they were likely enhanced by parental involvement. Both treatment programs and two of five prevention programs reduced weight/fat status. Our review highlights the need to evaluate more programs, advocate for use of a framework/behavioral theory and objective behavioral measures, further examine the impact of involving parents and the impact of intervention duration and follow‐up time, strengthen prevention programs, and further evaluate successful programs in other settings and among other racial/ethnic groups.     

Self-Esteem and Obesity in Children and Adolescents: A Literature Review

The relationship between self-esteem and obesity has not received a great deal of empirical evaluation using strong research methodologies. Thus, it is not clear whether self-esteem is consistently related to obesity, whether the relationship is global or specific to physical appearance, whether the relationship differs by demographic variables such as age, gender or race/ethnicity, or whether self-esteem moderates weight changes during weight loss treatment programs. This review examines these questions using empirical evidence from 35 studies on the relationship between self-esteem and obesity in children and adolescents. Thirteen of 25 cross sectional studies clearly showed lower self-esteem in obese adolescents and children. Five of the six cross-sectional studies that included a measure of body esteem found lower body esteem in obese compared to normal weight children and adolescents. Results from two prospective studies examining initial self-esteem and later obesity were inconsistent. Results from six of eight treatment studies showed that weight loss treatment programs appear to improve self-esteem. However, it is unclear whether increases in self-esteem are related to enhanced weight loss. Many studies were methodologically weak primarily due to small and select samples and lack of appropriate comparison groups. Implications for prevention and treatment of childhood obesity are discussed.     

Molecular and genetic mechanisms of obesity: implications for future management

Obesity has become a worldwide public health problem affecting millions of people. A disruption of the balance between energy intake and energy expenditure is believed to be the major cause of obesity. Substantial progress has been made in deciphering the pathogenesis of energy homeostasis over the past few years. The fact that obesity is under strong genetic control has been well established. Human monogenic obesity is rare in large populations, the most common form of obesity is considered to be a polygenic disorder arising from the interaction of multiple genetic and environmental factors. Here, we attempt to briefly review the most recent understanding of molecular mechanisms involved in energy homeostasis and adipogenesis. We discuss the advantages and disadvantages of various approaches commonly used in search for susceptibility genes for obesity. The main results from these genetic studies are summarized, with comments made on the most striking or representative findings. Finally, the implications of the recent advances in the understanding of molecular genetic mechanisms of body weight regulation on prevention and therapeutic intervention of obesity will be discussed.     

Short sleep duration and weight gain: a systematic review

Objective: The recent obesity epidemic has been accompanied by a parallel growth in chronic sleep deprivation. Physiologic studies suggest sleep deprivation may influence weight through effects on appetite, physical activity, and/or thermoregulation. This work reviews the literature regarding short sleep duration as an independent risk factor for obesity and weight gain. Methods and Procedures: A literature search was conducted for all articles published between 1966 and January 2007 using the search “sleep” and (“duration” or “hour” or “hours”) and (“obesity” or “weight”) in the MEDLINE database. Additional references were identified by reviewing bibliographies and contacting experts in the field. Studies reporting the association between sleep duration and at least one measure of weight were included. Results: Thirty‐six publications (31 cross‐sectional, 5 prospective, and 0 experimental) were identified. Findings in both cross‐sectional and cohort studies of children suggested short sleep duration is strongly and consistently associated with concurrent and future obesity. Results from adult cross‐sectional analyses were more mixed with 17 of 23 studies supporting an independent association between short sleep duration and increased weight. In contrast, all three longitudinal studies in adults found a positive association between short sleep duration and future weight. This relationship appeared to wane with age. Discussion: Short sleep duration appears independently associated with weight gain, particularly in younger age groups. However, major study design limitations preclude definitive conclusions. Further research with objective measures of sleep duration, repeated assessments of both sleep and weight, and experimental study designs that manipulate sleep are needed to better define the causal relationship of sleep deprivation on obesity.     

Modeling Social Transmission Dynamics of Unhealthy Behaviors for Evaluating Prevention and Treatment Interventions on Childhood Obesity

Research evidence indicates that obesity has spread through social networks, but lever points for interventions based on overlapping networks are not well studied. The objective of our research was to construct and parameterize a system dynamics model of the social transmission of behaviors through adult and youth influence in order to explore hypotheses and identify plausible lever points for future childhood obesity intervention research. Our objectives were: (1) to assess the sensitivity of childhood overweight and obesity prevalence to peer and adult social transmission rates, and (2) to test the effect of combinations of prevention and treatment interventions on the prevalence of childhood overweight and obesity. To address the first objective, we conducted two-way sensitivity analyses of adult-to-child and child-to-child social transmission in relation to childhood overweight and obesity prevalence. For the second objective, alternative combinations of prevention and treatment interventions were tested by varying model parameters of social transmission and weight loss behavior rates. Our results indicated child overweight and obesity prevalence might be slightly more sensitive to the same relative change in the adult-to-child compared to the child-to-child social transmission rate. In our simulations, alternatives with treatment alone, compared to prevention alone, reduced the prevalence of childhood overweight and obesity more after 10 years (1.2–1.8% and 0.2–1.0% greater reduction when targeted at children and adults respectively). Also, as the impact of adult interventions on children was increased, the rank of six alternatives that included adults became better (i.e., resulting in lower 10 year childhood overweight and obesity prevalence) than alternatives that only involved children. The findings imply that social transmission dynamics should be considered when designing both prevention and treatment intervention approaches. Finally, targeting adults may be more efficient, and research should strengthen and expand adult-focused interventions that have a high residual impact on children.     

Metabolic Determinants of Weight Gain in Humans

One of the fundamental challenges in obesity research is to identify subjects prone to weight gain so that obesity and its comorbidities can be promptly prevented or treated. The principles of thermodynamics as applied to human body energetics demonstrate that susceptibility to weight gain varies among individuals as a result of interindividual differences in energy expenditure and energy intake, two factors that counterbalance one another and determine daily energy balance and, ultimately, body weight change. This review focuses on the variability among individuals in human metabolism that determines weight change. Conflicting results have been reported about the role of interindividual differences in energy metabolism during energy balance in relation to future weight change. However, recent studies have shown that metabolic responses to acute, short‐term dietary interventions that create energy imbalance, such as low‐protein overfeeding or fasting for 24 hours, may reveal the underlying metabolic phenotype that determines the degree of resistance to diet‐induced weight loss or the propensity to spontaneous weight gain over time. Metabolically “thrifty” individuals, characterized by a predilection for saving energy in settings of undernutrition and dietary protein restriction, display a minimal increase in plasma fibroblast growth factor 21 concentrations in response to a low‐protein overfeeding diet and tend to gain more weight over time compared with metabolically “spendthrift” individuals. Similarly, interindividual variability in the causal relationship between energy expenditure and energy intake (“energy sensing”) and in the metabolic response to cold exposure (e.g., brown adipose tissue activation) seems, to some extent, to be indicative of individual propensity to weight gain. Thus, an increased understanding and the clinical characterization of phenotypic differences in energy metabolism among individuals (metabolic profile) may lead to new strategies to prevent weight gain or improve weight‐loss interventions by targeted therapies on the basis of metabolic phenotype and susceptibility to obesity in individual persons.     

Reducing overweight through a multidisciplinary school-based intervention

Objective: This study sought to evaluate the effectiveness of a multidisciplinary elementary school—based intervention entitled Wellness, Academics & You. The primary areas of impact examined were BMI, consumption of fruits and vegetables, and physical activity. Research Methods and Procedures: The sample consisted of 1013 students in fourth and fifth grades from 69 classes in four states. Intervention and comparison classes were randomly selected at each school. Intervention teachers participated in workshops on the intervention and received program materials. BMI was calculated for baseline and post‐data points based on measured height and weight collected by trained research teams. Baseline surveys were administered by the students’ teacher in the presence of one of the research team members and collected. Results: SPSS (SPSS, Inc., Chicago, IL) analysis of post‐data shows significant positive shifts (p = 0.01) in BMI in the intervention group compared with the comparison group. Notable increases in the consumption of fruits and vegetables and increased physical activity levels were reported in the intervention group. Discussion: Data from this study indicate that this school‐based program may contribute to the reduction of overweight and obesity. The intervention was well received by the classroom teachers and shows promise for a school‐based obesity prevention initiative. This program has shown the capacity to effect positive changes in BMI through consumption of fruits and vegetables and physical activity. The evaluation covered a limited time period and, therefore, warrants additional studies to determine whether long‐term program fidelity will result in continued improvement.     

具减肥功效的益生菌研究进展

摘要：肥胖症患病率在全球范围内持续增长,其中导致肥胖的最主要因素是能量摄入和消耗失衡。肠道菌群是涉及肥胖和代谢紊乱的环境因素,肥胖动物和人类患者表现出了肠道菌群组成和结构的改变。这种菌群失衡能影响机体能量平衡、炎症和肠道屏障功能等,进而影响代谢。研究显示益生菌可有效改善高脂饮食造成的肥胖。改变肠道菌群可能会成为预防或控制肥胖的有效疗法,该领域尚处于早期阶段,相关数据仍有限。本综述旨在总结最新的具有减肥功效益生菌的实验研究,帮助了解减肥益生菌的最新进展,为该领域后续研究提供帮助。     

A reagent resource to identify proteins and peptides of interest for the cancer community: a workshop report

On the basis of discussions with representatives from all sectors of the cancer research community, the National Cancer Institute (NCI) recognizes the immense opportunities to apply proteomics technologies to further cancer research. Validated and well characterized affinity capture reagents (e.g. antibodies, aptamers, and affibodies) will play a key role in proteomics research platforms for the prevention, early detection, treatment, and monitoring of cancer. To discuss ways to develop new resources and optimize current opportunities in this area, the NCI convened the "Proteomic Technologies Reagents Resource Workshop" in Chicago, IL on December 12-13, 2005. The workshop brought together leading scientists in proteomics research to discuss model systems for evaluating and delivering resources for reagents to support MS and affinity capture platforms. Speakers discussed issues and identified action items related to an overall vision for and proposed models for a shared proteomics reagents resource, applications of affinity capture methods in cancer research, quality control and validation of affinity capture reagents, considerations for target selection, and construction of a reagents database. The meeting also featured presentations and discussion from leading private sector investigators on state-of-the-art technologies and capabilities to meet the user community's needs. This workshop was developed as a component of the NCI's Clinical Proteomics Technologies Initiative for Cancer, a coordinated initiative that includes the establishment of reagent resources for the scientific community. This workshop report explores various approaches to develop a framework that will most effectively fulfill the needs of the NCI and the cancer research community.     

Obesity Research in Canada: Literature Overview of the Last 3 Decades

Objective: To identify research published on obesity in Canada, to explore the range of areas studied, and to identify gaps and areas that merit future research attention. Research Methods and Procedures: Medline and International Pharmaceutical Abstracts databases were searched from 1970 onwards. Original articles were identified and categorized by areas of interest. Results: A total of 1186 relevant articles were identified: 17, 136, 687, and 346 articles during the 1970s, 1980s, 1990s, and 2000 to 2003, respectively. Of the articles, 816 were considered original studies and accepted for this analysis. Twelve research areas were identified: basic science involving animal experiments (29%), human experiments (16%), populations surveys (14%), obesity‐related comorbidities (13%), diagnostic/surgical issues (11%), nonpharmacological approaches (7%), drug‐related issues (4%), anthropometrics (2%), impact of weight loss (2%), cost/healthcare use (1%), attitudes/perceptions (0.9%), and models/procedures (0.5%). Two‐thirds of all research was conducted in Quebec (34%) and Ontario (33%). Discussion: Given the multifactorial nature of obesity, Canadian obesity research covers a broad range of areas with a predominance of basic science but lesser emphasis on community and primary care studies. Furthermore, there was a paucity of research on either clinical management of medical conditions in obese patients or clinical aspects that go beyond weight loss. Thus, although Canada appears well represented in basic research, more attention to exploration of clinical issues and healthcare delivery for obese patients appears warranted.     

Paving the way for personalised behaviourally based prevention of obesity: systematic search of the literature

We have identified in the literature variants in 64 genes that may be involved in gene-obesity-behaviour interactions. Personalisation of behaviourally based preventive approaches against obesity seems feasible, however obesity genomics is still in the discovery phase of translational research and abundant replication studies are needed before these largely pioneering findings can be extended to practice and population impact. Automation of search algorithms and development of more efficient tools for knowledge synthesis of genomic research into gene-obesity-behaviour interactions might facilitate the advent of widely available personalised prevention approaches. Our future efforts shall therefore concentrate on developing such tools, as well as a research repository dedicated to the use of public health genomics for obesity control.     

Teaching cardiac electrophysiology modeling to undergraduate students: laboratory exercises and GPU programming for the study of arrhythmias and spiral wave dynamics

As part of a 3-wk intersession workshop funded by a National Science Foundation Expeditions in Computing award, 15 undergraduate students from the City University of New York(1) collaborated on a study aimed at characterizing the voltage dynamics and arrhythmogenic behavior of cardiac cells for a broad range of physiologically relevant conditions using an in silico model. The primary goal of the workshop was to cultivate student interest in computational modeling and analysis of complex systems by introducing them through lectures and laboratory activities to current research in cardiac modeling and by engaging them in a hands-on research experience. The success of the workshop lay in the exposure of the students to active researchers and experts in their fields, the use of hands-on activities to communicate important concepts, active engagement of the students in research, and explanations of the significance of results as the students generated them. The workshop content addressed how spiral waves of electrical activity are initiated in the heart and how different parameter values affect the dynamics of these reentrant waves. Spiral waves are clinically associated with tachycardia, when the waves remain stable, and with fibrillation, when the waves exhibit breakup. All in silico experiments were conducted by simulating a mathematical model of cardiac cells on graphics processing units instead of the standard central processing units of desktop computers. This approach decreased the run time for each simulation to almost real time, thereby allowing the students to quickly analyze and characterize the simulated arrhythmias. Results from these simulations, as well as some of the background and methodology taught during the workshop, is presented in this article along with the programming code and the explanations of simulation results in an effort to allow other teachers and students to perform their own demonstrations, simulations, and studies.