Constructs of health and environment inform child obesity prevention in American Indian communities

Objective: Obesity prevention efforts have had limited success in American Indian (AI) populations. More effective prevention programs might be designed using insights into linkages between parental health beliefs, environmental constraints and healthy lifestyle choices. Methods and Procedures: Focus group sessions (n = 42 participants) were conducted to explore parental perspectives on children's health, diet and physical activity in three Wisconsin Tribal communities. Focus group questions were derived from preliminary interviews and observations on environmental barriers surrounding nutrition and physical activity. Results: Two broad thematic areas emerged from the focus groups: child health themes and environmental themes. Health themes included views of child health (emphasizing emotional health), views on parenting, and assessment of risks to child safety. Environmental (social and physical) themes included assessments of personal support networks, assessments of local facilities and programs, and values regarding household relationships. A provisional model of family behaviors related to child nutrition and physical activity was developed to better understand these themes and the potential tensions among them. Discussion: Understanding the unique cultural constructs of health and environment of AI communities can inform decision making in community‐level prevention research. The proposed model served as a useful starting point for designing healthy lifestyle interventions in these AI communities. This model may also be applicable to other minority communities.     

A review of family and environmental correlates of health behaviors in high-risk youth

Disparities in the prevalence of obesity in youth place minority and low socioeconomic status youth at increased risk for the development of chronic disease, such as metabolic syndrome and type 2 diabetes. Contributing factors to the increases in obesity include a decline in positive health behaviors, such as making healthy dietary choices, engaging in physical activity, and limiting sedentary behaviors. Family and physical environmental contextual factors related to health behaviors are increasingly the focus of health behavior interventions in line with the bioecological model that encourages a system-focused perspective on understanding health behavior influences. Physical environmental characteristics, such as home and neighborhood characteristics and resources, provide the tangible means to support health behaviors and are important contextual variables to consider that may increase intervention effectiveness. Therefore, the current review seeks to highlight the importance of investigating influences of behavior beyond individual characteristics in understanding factors related to the risk of developing metabolic syndrome and type 2 diabetes in youth at high risk for developing chronic disease. The current study reviews the non-intervention literature on family and physical environmental factors related to health behaviors (i.e., diet, physical activity, and sedentary behavior) in youth who are considered to be at-risk for developing metabolic syndrome and type 2 diabetes. Results on 38 published articles of diet, physical activity, and sedentary behaviors showed support for the role of parenting and physical environmental factors, particularly parental monitoring and neighborhood context, such as social cohesion, as they relate to health behaviors in high-risk youth. Implications and recommendations for future research are discussed.     

Efficacy of a school-based childhood obesity intervention program in a rural southern community: TEAM Mississippi Project

A healthy lifestyle school-based obesity intervention was evaluated in a rural southern community where the rate of obesity ranks as the highest. School-age children (N = 450) ranging from 6 to 10 years of age (Mage = 8.34) participated in monthly physical activity and nutritional events during a 9-month academic year. The children's nutritional knowledge, number of different physical activities, fitness level, dietary habits, waist circumference, BMI percentile, and percentage body fat were measured pre- and postintervention. Changes on these measures were compared to students in a school employing the school system's standard health curriculum. Regression analyses with residualized change scores revealed that the intervention school showed statistically significant improvement in percentage body fat, physical activity, performance on fitness tests, and dietary habits compared to the control school. There was no evidence of differences in outcomes based on gender or ethnicity/race. With rates of obesity and overweight reaching 50% in southern rural communities, intervening early in development may offer the best outcome because of the difficulties with changing lifestyle behaviors later in adulthood. A population-based approach is recommended over a targeted approach to cultivate a culture of healthy lifestyle behaviors when children are developing their health-care habits. Evidence suggests that both boys and girls, and African-American and white children can benefit equally from such interventions.     

城市居住区多功能绿地景观的景感生态学效应

作为居住区绿地景观重要的组成要素,公共活动空间是居民最为频繁使用的空间,对提高绿地生态系统文化服务,改善人居环境与提高居民健康具有重要意义。基于居民休闲娱乐文化感知,探讨居住区绿地公共活动空间的景感生态学效应,揭示多功能绿地景观对生态系统文化服务和景感营造的影响,可为居住区绿地的景观规划与设计提供重要的参考依据。以郑州市26个居住小区80个公共活动空间为研究对象,结合景感生态学理念,基于小区绿地公共活动空间的景感特征（植被覆盖、基础设施、遮荫率、管理水平、公共活动空间面积与类型）以及内部居民休闲娱乐文化活动特征的调查分析,探讨了城市居住区绿地公共活动空间的景感效应对绿地生态系统文化服务的影响。结果表明：（1）小区绿地不同类型公共活动空间提供的景感效应存在显著差异,水体的自然属性使其景感效应更丰富,文化服务价值最高。（2）小区绿地公共活动空间面积越大,居民的心理感知越强,景感体验越丰富,文化服务价值越高,增加公共活动空间面积是构建多功能绿地景观的直接通道。（3）公共活动空间的植被覆盖营造的视感与遮荫率营造的风感生态学效应较为显著,而基础设施的触感与清洁度的视感并未存在显著影响。（4）结合小区社会经济数据的多元回归分析结果表明,由公共活动空间面积营造的多样化景感对居民活动量的贡献最大,其次为公共活动空间的类型与小区户数。运用景感生态学理论和景感营造原则,在有限的空间内通过景观设计实现了景感载体化,改善和增加了绿地生态系统服务,能够缓解城市绿地的不公平性。未来城市居住区特别是高密度居住区应尽可能设置大面积的具有多功能特征的公共活动空间,而低密度居住区在绿地面积充足的前提下,可设置大面积自然水体和增设多类型的公共活动空间,以提高景感效应。     

Review of the physiology of human thermal comfort while exercising in urban landscapes and implications for bioclimatic design

This review comprehensively examines scientific literature pertaining to human physiology during exercise, including mechanisms of heat formation and dissipation, heat stress on the body, the importance of skin temperature monitoring, the effects of clothing, and microclimatic measurements. This provides a critical foundation for microclimatologists and biometeorologists in the understanding of experiments involving human physiology. The importance of the psychological aspects of how an individual perceives an outdoor environment are also reviewed, emphasizing many factors that can indirectly affect thermal comfort (TC). Past and current efforts to develop accurate human comfort models are described, as well as how these models can be used to develop resilient and comfortable outdoor spaces for physical activity. Lack of suitable spaces plays a large role in the deterioration of human health due to physical inactivity, leading to higher rates of illness, heart disease, obesity and heat-related casualties. This trend will continue if urban designers do not make use of current knowledge of bioclimatic urban design, which must be synthesized with physiology, psychology and microclimatology. Increased research is required for furthering our knowledge on the outdoor human energy balance concept and bioclimatic design for health and well-being in urban areas.     

Workplace Social and Organizational Environments and Healthy-Weight Behaviors

Background

The workplace is an important setting for health promotion including nutrition and physical activity behaviors to prevent obesity. This paper explores the relationship between workplace social environment and cultural factors and diet and physical activity (PA) behaviors and obesity among employees.

Methods

Between 2012 and 2013, telephone interviews were conducted with participants residing in four Missouri metropolitan areas. Questions included demographic characteristics, workplace socio/organizational factors related to activity and diet, and individual diet and PA behaviors, and obesity. Multivariate logistic regression was used to examine associations between the workplace socio/organizational environment and nutrition, PA, and obesity.

Results

There were differences in reported health behaviors and socio/organizational environment by gender, race, age, income, and worksite size. For example, agreement with the statement the ‘company values my health’ was highest among Whites, older employees, and higher income workers. As worksite size increased, the frequency of reporting seeing co-workers doing several types of healthy behaviors (eat fruits and vegetables, doing PA, and doing PA on breaks at work) increased. In adjusted analyses, employees agreeing the company values my health were more likely to engage in higher PA levels (aOR=1.54, 95% CI: 1.09-2.16) and less likely to be obese (aOR=0.73, 95% CI: 0.54-0.98). Seeing co-workers eating fruits and vegetables was associated with increased reporting of eating at least one vegetable per day (aOR=1.43, 95% CI: 1.06-1.91) and seeing co-workers being active was associated with higher PA levels (aOR 1.56, 95% CI: 1.19-2.05).

Conclusions

This research suggests that social/organizational characteristics of the workplace environment, particularly feeling the company values the workers’ health and to seeing co-workers engaging in healthy behaviors, may be related to nutrition and PA behaviors and obesity. These findings point to the potential for intervention targets including environment and policy changes.     

Changes in the Regional Prevalence of Child Obesity in 4th, 8th,and 11th Grade Students in Texas From 2000–2002 to 2004–2005

Although national and state estimates of child obesity are available, data at these levels are insufficient to monitor effects of local obesity prevention initiatives. The purpose of this study was to examine regional changes in the prevalence of obesity due to statewide policies and programs among children in grades 4, 8, and 11 in Texas Health Services Regions (HSRs) between 2000–2002 and 2004–2005, and nine selected counties in 2004–2005. A cross‐sectional, probability‐based sample of 23,190 Texas students in grades 4, 8, and 11 were weighed and measured to obtain BMI. Obesity was >95th percentile for BMI by age/sex using Centers for Disease Control and Prevention growth charts. Child obesity prevalence significantly decreased between 2000–2002 and 2004–2005 for 4th grade students in the El Paso HSR (?7.0%, P = 0.005). A leveling off in the prevalence of obesity was noted for all other regions for grades 4, 8, and 11. County‐level data supported the statistically significant decreases noted in the El Paso region. The reduction of child obesity levels observed in the El Paso area is one of the few examples of effective programs and policies based on a population‐wide survey: in this region, a local foundation funded extensive regional implementation of community programs for obesity prevention, including an evidence‐based elementary school‐based health promotion program, adult nutrition and physical activity programs, and a radio and television advertising campaign. Results emphasize the need for sustained school, community, and policy efforts, and that these efforts can result in decreases in child obesity at the population level.     

Wise Mind project: a school-based environmental approach for preventing weight gain in children

Objective: The Wise Mind pilot study compared the efficacy of an environmental approach for prevention of inappropriate weight gain in children with an active control condition that used an environmental approach for modifying expectancies related to the use of alcohol, tobacco, and drugs. Research Methods and Procedures: A total of 670 second to sixth grade students from four schools were enrolled in the study. The study spanned 2 academic years, and 586 students were available for evaluation at the end of the study. Two schools were randomly assigned to each treatment arm. The environmental approach for weight gain prevention focused on modification of eating habits and physical activity, and the active control group focused on modification of expectancies related to substance use. Results: Using an intention to treat design, the study found no differences in weight gain prevention between the two interventions. The weight gain prevention program was associated with reduction of total caloric intake, reduction of dietary fat intake, reduction of protein intake, and increased physical activity in comparison with the active control group and relative to baseline. These changes in food intake were attributed to changes in food selections that resulted from modification of school cafeteria menus and food preparation. Discussion: The Wise Mind school‐based weight gain prevention program induced behavioral changes in healthy eating and physical activity but did not induce significant changes in body weight in comparison with the control arm. Recommendations for future research are provided.     

Relationship between perceptions about neighborhood environment and prevalent obesity: data from the dallas heart study

Objectives:

Although psychosocial stress can result in adverse health outcomes, little is known about how perceptions of neighborhood conditions, a measure of environment‐derived stress, may impact obesity. The association between perceptions of neighborhood environment and obesity (defined as body mass index [BMI] ≥ 30 kg/m²) among 5,907 participants in the Dallas Heart Study, a multi‐ethnic, probability‐based sample of Dallas County residents was examined.

Design and Methods:

Participants were asked to respond to 18 questions about perceptions of their neighborhood. Factor analysis was used to identify three factors associated with neighborhood perceptions: neighborhood violence, physical environment, and social cohesion. Logistic regression analyses were performed to determine the relationship between each factor (higher quintile = more unfavorable perceptions) and the odds of obesity.

Results:

Decreasing age, income, and education associated with unfavorable overall neighborhood perceptions and unfavorable perceptions about specific neighborhood factors (P trend <0.05 for all). Increasing BMI was associated with unfavorable perceptions about physical environment (P trend <0.05) but not violence or social cohesion. After adjustment for race, age, sex, income, education, and length of residence, physical environment perception score in the highest quintile remained associated with a 25% greater odds of obesity (OR 1.25, [95% CI 1.03‐1.50]). Predictors of obesity related to environmental perceptions included heavy traffic (OR 1.39, [1.17‐1.64]), trash/litter in neighborhood (OR 1.27, [1.01‐1.46]), lack of recreational areas (OR 1.21, [1.01‐1.46]), and lack of sidewalks (OR 1.25, [95% CI 1.04‐1.51]).

Conclusions:

Thus, unfavorable perceptions of environmental physical conditions are related to increased obesity. Efforts to improve the physical characteristics of neighborhoods, or the perceptions of those characteristics, may assist in the prevention of obesity in this community.     

Beyond Proximity: The Importance of Green Space Useability to Self-Reported Health

Access to parks and green spaces within residential neighbourhoods has been shown to be an important pathway to generating better physical and mental health for individuals and communities. Early research in this area often failed to identify specific attributes that contributed to reported health outcomes, with more recent research focused on exploring relationships between health outcomes and aspects of access and design. A mixed methods research project conducted in Perth, Western Australia examined the role that neighbourhood green space played in influencing residents’ self-reported health status, and this paper identifies significant relationships found between perceptions of green space quality and self-reported health. It focuses on the factors that were found to be most positively associated with better health outcomes: proximity, retention, useability and visitation of neighbourhood green space.     

Pathways to Obesity Prevention: Report of a National Institutes of Health Workshop1

There is an extensive research base on obesity treatment and on the health benefits of weight loss, but relatively little research has focused on obesity prevention. This article summarizes results of a workshop conducted by investigators funded under a National Institutes of Health initiative designed to stimulate novel research for obesity prevention. The 20 pilot studies funded under this initiative involved study populations that were diverse with respect to life stage and ethnicity, were conducted in a variety of natural and research settings, and involved a mix of interventions, including face‐to‐face group and individual counseling, as well as mail, telephone, and internet‐based approaches. The workshop, which occurred approximately halfway through the 3‐year funding period, emphasized concepts and experiences related to initiating and conducting obesity prevention studies. Investigators discussed theoretical perspectives as well as various challenges encountered, for example, in study implementation in different clinical and community settings, in working with children and families, and in studying pregnant and postpartum women. Other topics discussed included the difficulty of motivating individuals for prevention of weight gain, relevant cultural and racial/ethnic considerations, and the particular need for valid and practical measures of energy balance, body composition, and physical fitness in obesity prevention research. A key conclusion was that using obesity treatment as the primary paradigm may be a limiting perspective for considering obesity prevention issues. Further insights derived from the workshop deliberations are reflected in a detailed list of recommendations for future obesity prevention research.     

School-based obesity prevention programs: an evidence-based review

Objective: This review seeks to examine the effectiveness of school‐based programs for reducing childhood overweight or obesity. Methods and Procedures: A systematic review of the research literature published since 1990 was conducted to identify experimental or quasi‐experimental school‐based curricular or environmental preventive interventions, with evaluation ≥ 6 months after baseline, which reported outcomes in terms of a measure of overweight. Results: Fourteen studies were identified, including one involving a nutrition‐only program, two physical activity promotion interventions and eleven studies combining nutrition and physical activity components. Most studies (n = 10) offered weak (grade 2) quality evidence. One study offered strong (grade 4) evidence reducing the odds ratio for overweight in girls only, while four grade 2 studies reported significant improvements in BMI or at‐risk‐for overweight or overweight prevalence in boys, girls, or both. Twelve studies reported significant improvement in at least one measure of dietary intake, physical activity, and/or sedentary behavior. Discussion: Our ability to draw strong conclusions as to the efficacy of school‐based obesity prevention programs is limited by the small number of published studies and by methodological concerns. Qualitative analysis suggests programs grounded in social learning may be more appropriate for girls, while structural and environmental interventions enabling physical activity may be more effective for boys. High‐quality evaluation protocols should be considered essential components of future programs.     

景感生态学视角下的健康社区构建

景感生态学是基于中国传统人居环境营造理论与实践结合现代生态学基本原理形成的新兴学科,注重探讨生态系统服务与可持续发展的关系。可持续发展目标中健康与福祉是其重要内容,因此健康人居环境的营造也是景感生态学的重要应用领域之一。在健康人居环境的营造过程中,健康社区构建具有作为"细胞工程"的基础性作用。因此,从景感生态学的视角探讨健康社区的构建,有助于景感生态学进一步应用于可持续发展与人居环境营造的实践,为健康与福祉的顺利实现提供支撑。从健康社区的定义和主要理念出发,基于健康社区构建的需求本体和供给客体及其相互作用关系,结合生态环境科学的"时-空-量-序"的视角,探讨了生态环境研究应用于健康社区构建的作用及面临的系统性不足、人文性不足和耦合性不足等挑战;进而以景感生态学作为连接生态环境学科与建筑规划学科的纽带,探讨了景感生态学在应对上述挑战中的作用。从景感生态学视角来看,健康社区构建就是将人类健康这一愿景融入到社区健康需求本体与健康供给客体及其相互关系的调控与营造,从而实现社区及人群的健康和可持续发展。健康社区的构建强调社区人群主观健康需求与客观健康供给之间的互动与耦合,与景感生态学强调"景"与...     

西安市城区初中生健康危险行为调查

目的:健康相关危险行为是产生常见病、多发病的重要原因,其形成受社会、家庭等多种环境因素和自身因素影响。初中阶段是养成良好健康行为的关键时期,了解初中生健康危险行为现状,可为制定干预措施提供科学依据。方法:对西安市城区1608名初中生进行健康危险行为问卷调查,分析各种健康危险行为检出率的性别差别。结果:34.3%的初中生存在偏食行为,42.6%的初中生在过去30天内采取过减肥措施;62.2%的初中生最多有2天运动超过30分钟;65.3%的初中生骑自行车违规;9.6%的初中生目前吸烟。过去1个月有大量饮酒行为者占8.4%。因上网影响学习者占17.0%;参与过类似赌博的娱乐活动者占9.8%。多数健康危险行为检出率男生高于女生(P值均0.05)。结论:西安市城区初中生健康危险行为发生率较高,男女生间存在差异,应针对男女生不同健康危险行为,采取有针对性的综合干预措施进行干预,以及早纠正健康危险行为,促进青少年健康发展。     

Three-Year Improvements in Weight Status and Weight-Related Behaviors in Middle School Students: The Healthy Choices Study

Introduction

Few dissemination evaluations exist to document the effectiveness of evidence-based childhood obesity interventions outside the research setting.

Objective

Evaluate Healthy Choices (HC), a multi-component obesity prevention program, by examining school-level changes in weight-related behaviors and weight status and the association of implementation components with odds of overweight/obesity.

Methods

We compared baseline and Year 3 school-level behavioral and weight status outcomes with paired t-tests adjusted for schools’ socio-demographic characteristics. We used generalized estimating equations to examine the odds of overweight/obesity associated with program components.

Setting/Participants

Consecutive sample of 45 of 51 middle schools participating in the HC program with complete baseline and follow-up survey data including a subsample of 35 schools with measured anthropomentry for 5,665 7^th grade students.

Intervention

Schools developed a multi-disciplinary team and implemented an obesity prevention curriculum, before and after school activities, environmental and policy changes and health promotions targeting a 5-2-1 theme: eat ≥ 5 servings/day of fruits and vegetables (FV), watch ≤ 2 hours of television (TV) and participate in ≥ 1 hours/day of physical activity (PA) on most days

Main Outcome Measures

1) School-level percent of students achieving targeted behaviors and percent overweight/obese; and 2) individual odds of overweight/obesity.

Results

The percent achieving behavioral goals over three years increased significantly for FV: 16.4 to 19.4 (p = 0.001), TV: 53.4 to 58.2 (p = 0.003) and PA: 37.1 to 39.9 (p = 0.02), adjusting for school size, baseline mean age and percent female, non-Hispanic White, and eligible for free and reduced price lunch. In 35 schools with anthropometry, the percent of overweight/obese 7^th grade students decreased from 42.1 to 38.4 (p = 0.016). Having a team that met the HC definition was associated with lower odds of overweight/obesity (OR = 0.83, CI: 0.71–0.98).

Conclusions and Relevance

The HC multi-component intervention demonstrated three-year improvements in weight-related behaviors and weight status across diverse middle schools. Team building appears important to the program’s effectiveness.     

城市绿地对居民身心福祉的影响

城市绿地是人工与自然耦合的城市景观之一,是改善居民居住环境重要组成部分,更是提高居民身心健康的有效途径。以杭州主城区为研究对象,通过GIS技术对城市绿地遥感图像进行解译得到杭州主城区绿地空间布局图,同时,以人口密度为阻力要素,基于交通路网的500m网络距离可达范围内绿地数量和面积作为分类标准。通过对45个高、中、低不同档次的居民区进行问卷调查得到665份居民感知数据并进行统计整理。利用结构方程模型进行以绿地数量及游玩时间为标准的组间分析,区别不同组别的差异及其原因,分析城市绿地数量、面积,居民认知、动机,绿地吸引力等与居民身心健康福祉及满意度之间的关系。结果显示:城市绿地数量、居民游玩绿地次数时间等与居民福祉有显著的正向关系;居民对绿地作用的认知、去往绿地的动机进一步影响居民身心健康福祉;城市绿地的自身引力会激发居民去往绿地的积极性,从而增加去往绿地频次。另外,不同社会属性的个体对绿地需求不同,所产生的福祉效应及满意度也会有所差异。从增加居民区周围的街头绿地及邻里公园数量、提升绿地吸引力、提升居民对城市绿地作用的认知3个方面对城市绿地今后的发展规划提出建议。     

Exploring the Potential of a School Impact on Pupil Weight Status: Exploratory Factor Analysis and Repeat Cross-Sectional Study of the National Child Measurement Programme

Schools are common sites for obesity prevention interventions. Although many theories suggest that the school context influences weight status, there has been little empirical research. The objective of this study was to explore whether features of the school context were consistently and meaningfully associated with pupil weight status (overweight or obese). Exploratory factor analysis of routinely collected data on 319 primary schools in Devon, England, was used to identify possible school-based contextual factors. Repeated cross-sectional multilevel analysis of five years (2006/07-2010/11) of data from the National Child Measurement Programme was then used to test for consistent and meaningful associations. Four school-based contextual factors were derived which ranked schools according to deprivation, location, resource and prioritisation of physical activity. None of which were meaningfully and consistently associated with pupil weight status, across the five years. The lack of consistent associations between the factors and pupil weight status suggests that the school context is not inherently obesogenic. In contrast, incorporating findings from education research indicates that schools may be equalising weight status, and obesity prevention research, policy and practice might need to address what is happening outside schools and particularly during the school holidays.     

基于深度学习街景影像解译和景感生态学的视域环境定量解读

城市物理环境带给居民丰富而生动的视觉意象,目前许多文献结果表明其宜人性与公共福祉以及健康状况息息相关。景感生态为探究城市物理环境与居民感知信息之间的联系提供了指导依据,通过人本尺度的定量手段解读城市环境中视觉、听觉和味觉等多维度感知信息。秉承景感生态学的基本原理,引入一种结合街景大数据和深度学习的城市环境量化手段,以北京市六环范围为例,将景感视率作为测度对人本视角下的城市环境展开定量解读。在全面把控多维景感要素的同时,旨在实现以人为本的城市物理环境优化设计,从而满足人们对生活品质提升的实际需求。实验结果显示:(1)从视觉感受的宏观表现来看,北京四环路范围内建成环境的"闭合感"较强,而对绿植的感知程度相对偏弱,因而需要开展存量环境设计并优化视域界面结构;(2)以景感视率作为特征值进行聚类得出3类主导空间(绿色空间、灰色空间和蓝色空间),可针对灰色空间着重部署垂直绿化资源,提高城市视觉绿化的可感知性,从而营造舒适宜人的绿色氛围、促进公众身心健康;(3)为景感生态学提供了基于大数据思维的数据集和定量方法补充。综上,以街景影像和景感生态视角对北京市中心城区的视域环境展开定量分析,采用了先进的深...     

面向环境管理的城市代谢物质实体空间研究评述

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