NC1028: Promoting healthful eating to prevent excessive weight gain in young adults (NC219)
(Multistate Research Project)
Status: Inactive/Terminating
NC1028: Promoting healthful eating to prevent excessive weight gain in young adults (NC219)
Duration: 10/01/2006 to 09/30/2011
Administrative Advisor(s):
NIFA Reps:
Non-Technical Summary
Statement of Issues and Justification
STATEMENT OF THE PROBLEM: Risks of cardiovascular disease, hypertension, and type 2 diabetes are exacerbated by excessive weight gain. Development of specific strategies is needed to promote healthful eating among young adults, an age group with high risk of weight gain and unique interests in diet/health issues. To date, few interventions have been designed for obesity prevention among young adults. This multi-state research group is currently designing an intervention to prevent weight gain and promote healthy diet/exercise choices among young adult college students. The experimental intervention will utilize principles of community-based participatory research (CBPR), a collaborative approach to research that equitably involves & community members, organizational representatives, and researchers in all aspects of the research process'(1).
In previous research, we have been successful at developing theory-based education strategies for low-income young adults between the ages of 18-24. In comparison to a control group receiving a minimal standard treatment, young adults ate more servings of fruits and vegetables when exposed to a tailored intervention with practical age-appropriate messages. However, young adults were more likely to drop from the intervention study if they had very low incomes (<$800/month), were of ethnic minority status and/or were parents. The new intervention will utilize principles of CBPR to increase relevance and accessibility and reduce the attrition we found in our previous research. .
JUSTIFICATION:
Extent of the problem
Recent data from the US Centers for Disease Control and Prevention show continued escalation of the prevalence and severity of obesity in all age, gender and socioeconomic segments of the population, costing the US an estimated $75 billion annually (2). Obesity has increased dramatically since 1991, and now approximately 64% of American adults are overweight or obese (3, 4). Recent epidemiological studies have documented that young adulthood is a critical time in which adverse changes in body weight are likely to occur, and that men and women aged 18-25 are a subset of young adults at particularly high risk for weight gain (5, 6, 7). Being mildly or moderately overweight at age 20-22 years is linked with substantial incidence of obesity by age 35-37 years (8,9). This high-risk age group extends across all racial and ethnic groups, however the rate of weight gain is higher in Blacks, Americans Indians, and Hispanics than non-Hispanic whites (5).
Investigators from the Coronary Artery Risk Development in Young Adults (CARDIA) found young adults gained an average of 0.69 plus or minus 1.19 kg/yr over 10 years (5). The rate of weight gain appeared to slow in subsequent decades to an average of around 0.5 kg/yr (10). While genetic factors undoubtedly contribute to obesity development (11,12), they cannot explain the escalation in recent years nor differences in rate of weight gain by age (13). A chronic state of positive energy balance must exist for weight gain to occur, which is made possible by increased energy intake relative to energy expenditure(12). The Diabetes Prevention Program (DPP) demonstrated that healthy eating and physical activity can achieve modest weight loss among older adults (>=25 years) at high risk of developing diabetes. This study utilized a clinical approach to providing extensive education on nutrition, physical activity, and behavior modification (14).
There are many serious health implications of overweight and obesity, making excess body weight one of the leading causes of preventable death in the U.S.(15) and a serious concern for the nation's health care system and overall economy (12,16). Weight reduction helps to reduce the risk and severity of the most prevalent chronic disease conditions, requiring as little as 5-10% weight loss (2). The Institute of Medicine (IOM) provided guidelines for effective weight loss programs, recommending the combination of diet, exercise and behavior modification (12). In a review of 12 weight loss trials completed between 1990 and 2000, which followed IOM guidelines, average weight loss was 10.4 kg (17). Intensive treatment including diet, exercise and behavior modification has been effective in generating a 5-10% weight loss for those completing a year of treatment (17). However, most overweight individuals are either not prepared or are not able to participate in such programs (7, 18) or if they start, more than one-third will fail to complete treatment and follow-up (19, 20). Even if obese persons participate and complete treatment, they are unlikely to lose sufficient weight to return to a normal weight range(12). Less intensive approaches have produced only minimal or modest weight loss (20, 21).
Few interventions have been designed with an obesity-prevention outcome for college-age individuals. In a review published in 2000, only one randomized controlled trial (RCT) was effective for weight gain prevention (22). The initial Pound of Prevention Intervention study (23) found that treatment consisting of a substantial contingency contract ($120) along with newsletters and a group educational program was more effective in preventing weight gain over 12 months (82%) than a control group (56%). However, in an attempt to replicate results without contingency contracting in a larger more diverse sample, there was no difference between groups at either 12 or 36 months; all groups gained an average of 0.5 kg/yr (24). Leermarkers et al. conducted an investigation of home- or clinic-based diet and exercise programs vs. a no-treatment control to prevent weight gain in young adult men with a BMI of 22-30 (25). Both programs were effective in producing an average weight loss of 1.6 kg over four months compared to the mean gain of 0.2 kg in control subjects; however the sample size was small (n=74) and there was no follow-up. The Midwest Exercise Trial (26) sought to determine whether a 16-month controlled, supervised exercise program could prevent weight gain in sedentary overweight young adults. The exercise group expended approximately 2000 kcal/week in exercise while the controls were instructed to maintain their usual physical activity patterns throughout the study. Results showed that without dietary changes, exercise facilitated a 5.2 kg weight loss in men while the exercising women avoided the 3 kg weight gain seen in the control group. Although the sample completing the study was small (n=67) and attrition high (44%), this study demonstrated that a high level of exercise could prevent weight gain in young adults without dietary restriction. The National Weight Control Registry that tracks reported strategies used by adults to achieve and maintain extensive weight loss also reported the value of routine exercise (REF). The recent STRIDDE (Studies of Targeted Risk Reduction Interventions Through Defined Exercise) investigation (27) found that in non-dieting overweight subjects the equivalent of walking 30 minutes per day was sufficient to prevent weight gain over the course of the eight-month program. These findings indicate the importance of moderate exercise for weight gain prevention.
The Women's Healthy Lifestyle program found that an intensive, individualized traditional diet (TD) approach designed to accomplish modest weight loss was effective in preventing net gain over 5 years (mean=-0.1 kg) compared to the control group (mean=+2.5 kg) (28). In addition, although not designed as a weight gain prevention program, the Diabetes Prevention Program also found modest weight loss and behavioral skill development prevented net gain over time (29). Although results of these programs have been promising, most of these programs utilized diet and/or exercise to generate an initial weight loss in order to prevent net gain over time. Like most TD programs, the initial weight loss was followed by some degree of weight gain. Only two of the programs (25, 26) focused on young adults and both programs had small, homogeneous samples. Clearly, there is a need for a more focused study for primary prevention of weight gain in young adults.
The American Public Health Association has a detailed policy statement supporting CBPR in public health (30). To better understand the social and environmental determinants of health we need to move away from the traditional research model. Rather than passive involvement of research participants, CBPR calls for active collaboration with the community to more effectively solve their problems. Communities need to set priorities for how to handle their problems including obesity (31). CBPR is typically used with a definable local community, but can also be used across a broad community, such as a collection of college campuses. CBPR has been used successfully for the development and implementation of the large scale California Health Interview Survey so that the information collected would best meet the needs of agencies/populations using the resulting data. Advisory boards involving 145 people representing the 60 agencies who used the results were involved in each step of the process (32). PRECEDE-PROCEED (33) is a CBPR model that can be used with local or very broad communities to untangle and understand the complex behavioral and environmental factors that influence health and quality of life. To achieve broad and sustained change in environmental forces and behavioral patterns, it is necessary to use a participatory model to both plan and implement multiple strategies (34).
Benefits
Using participatory research investigators work side-by-side with the target audience to understand, develop, and create interventions desired by the target audience. The process will uncover the necessary background information and knowledge to understand how issues important to young adults such as environment and quality of life affect their diet, activity, and life style choices. Grant funding will be pursued for this participatory research and for the resulting intervention projects, as well as smaller state/local projects. The ultimate outcome of this work will be educationally appropriate materials and interventions that meet the young adult groups' needs in their acquisition of healthful eating and prevention of weight gain. The collective power of the multiple states collaborating throughout the entire participatory process will significantly contribute to the understanding of how to best meet young adults' needs as they strive to prevent weight gain and adopt healthful habits. The outcomes from this work address health promotion priorities of USDA and other agencies such as NIH.
Need for cooperative work
Need for cooperative work
In previous studies (NC200, NC219, NC219 renewal multi-state research) the NC219 research team has established a strong record of collaborative research demonstrated by a publication record with multiple authors from different institutions (see Critical Review). This groups has been successful at leveraging grant funding, including an Initiative for Future Agriculture and Food Systems (IFAFS) grant and two National Research Initiative (NRI) grants. NC219 researchers developed significant depth in the understanding of young adult food choice behavior and differences by gender and stages of readiness to change. The cooperation of a multi-state project benefits the proposed research by offering access to a wider variety of young adults than possible at a single institution. In previous work, some regional differences in demographics and in food choice behavior were evident. Racial and ethnic group representation also varied. Our collaborative relationship permits development of a much larger and more intricate project than possible within any one state alone. For example, last year, NC219 researchers in 10 states completed a behavioral intervention for low income young adults using extension/education/research partnerships. Over 2000 economically disadvantaged young adults were recruited and enrolled in a 12-month intervention study. The focus was on underserved populations of non-college young adults. Attrition rates were higher for participants with education dhigh school, experimental group assignment, non-white ethnicity or race, male gender, living with children, and income < $ 800/month (Chi squared, 6df =288, P<.001, Cox R2 =.132). With NRI support, NC219 researchers from 8 states are currently collaborating to develop a web-based intervention for weight gain prevention in college students.
The proposed study will use CBPR to expand the scope of the NRI intervention and address the quality of life, health, behavioral, environmental, and educational needs identified by college students. Our long range plan is to build on the NRI and CBPR with college students to extend to economically-disadvantaged young adults. Multi-state collaboration, by researchers and young adults as proposed for the current study, will provide experience in collaborative, community-based research that will complement the NRI-funded web-based intervention. The relationships that we have previously developed with Extension and other community partners will aid in achieving our long-range goal of using CBPR to provide integrated interventions to hard-to-reach populations of young adults. The larger and more diverse sample afforded through cooperative work increases the power and ability to generalize the results of research findings.
Related, Current and Previous Work
A CRIS review found 82 projects related to obesity and weight gain prevention. Although three (Ferris, Poehlitz, OConnel, Gould, 2005; Ahmedna, Sanchez-Lugo, Swearingin, Wilson, Grub, Sherman, 2005; Kolodinsky, Harvey-Berino, Berlin, 2005) targeted young adults (18-24 years old) and one (Macpherson-Sanchez, Rodriguez M, Seijo-Maldonato, Rodriguez R; 2005) focused on participatory research, there was no duplication of the proposed project. Ferris, Ahmedna, and Macpherson-Sanchez projects were service-learning or developmental grants and Kolodinsky focused on a point-of-purchase environmental intervention. The only project closely related to the proposed NC 219 project was our own NRI project (Greene, Riebe, Rossi, Blissmer, Phillips, White, Hoerr, Horacek, Lohse, Patterson, Kattelmann, Kritsch, 2005). The relationship between the two will be discussed below.
This renewal builds on the 15 years of research conducted by members of NC 219 addressing eating behaviors in young adults. In addition, studies arising from the NC 219 research group (IFAFS, NRI, and doctoral dissertations by Kimberly Shafer and Sangjen Chung) provide the background for this project. Our IFAFS-funded research found that tailored interventions were effective in increasing fruit and vegetable intake in economically disadvantaged young adults. However, there was a significantly higher attrition rate among minority participants, suggesting a need for a better understanding about intervention modalities and themes in minority populations. Shafer found that the American Indian population was not willing to negatively evaluate intervention materials but would provide needed feedback by expressing preference for one example compared to another (35). Chung found that fewer processes of change were used by young adults than by older adults to eat fruits and vegetables. Chung also found that living environment and eating breakfast increased intakes of fruits and vegetables in young adults (36).
The NRI project initiated in 2005 is developing a web-based intervention for obesity prevention in college students. The proposed study will use CBPR to expand the scope of the NRI intervention to focus on quality of life, behavioral and environmental issues related to college students health and nutrition needs. Multi-state collaboration, by researchers and young adults, as proposed for the current study will provide experience in collaborative, community-based research that will complement the NRI-funded web-based intervention. Our long-range plan is to build on the NRI and CBPR with college students to develop model integrated interventions for economically disadvantaged young adults.
A recent Institute of Medicine report has recommended public health professionals be taught how to conduct CBPR to reflect the social and ecological view of health and disease in their work (34). Although many of the research and Extension partners on the NC219 team have some experience with participatory research, members of the research team from NY provide special expertise in utilizing the PRECEDE-PROCEED model. NY used PRECEDE-PROCEED to work with the appropriate target communities to develop a Peer Nutrition Education, a Worksite Wellness program (37, 38, 39, 40) a Non-diet weight management program for military dependents (Cole PhD Dissertation, Horacek advisor), an obesity reduction/prevention program through five black churches in Syracuse (Cowart, Horacek - consultant). NY will lead the full NC219 team in fully implementing CBPR.
Objectives
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Enhance NC219 researchers' skills in participatory research techniques and to build partnerships among researchers, extension and outreach educators, and populations of young adults to develop cooperative intervention programs.
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Use participatory research techniques to assess, prioritize, and connect: (a) young-adults' quality of life issues and needs (Social Diagnosis); (b) young-adults' perceived health issues, and the behavioral and environmental health determinants (Health, Behavioral and Environmental Diagnosis); (c) young-adults' specific predisposing, reinforcing, and enabling factors determining their health and quality of life (Educational and Ecological Diagnosis).
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Address needs identified in objective 2 by compiling and evaluating evidence-based methods and material for promoting healthful eating and/or prevention of weight gain (Administrative and Policy Diagnosis).
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Develop community based applications that can be refined and evaluated in future projects.
Methods
METHODS: This 5-year project will focus on college populations, but individual states may also initiate CBPR projects with non-college populations. The long-range goal is to develop a CBPR-based model that integrates research, extension, and communities of young adults. Using the PRECEDE-PROCEED (33) model of participatory research will help us to work with our target populations to identify and prioritize the problems of significance (quality of life/health/and environmental & behavioral determinants and predisposing/enabling and reinforcing factors) to them which can then be connected to the most appropriate nutrition issues. By using a participatory research model, we are also more likely to develop an intervention desired by the target population and thus one that is sustainable. Objective 1 Procedures Principal investigator skills in participatory research techniques will be enhanced through collaboration and training with participatory research experts. This training will occur in conjunction with the annual meeting and via regular teleconferences. In order to develop effective interventions for these young adults, we need to build the necessary partnerships with outreach educators and substantive populations of young adults. The first year will be devoted to enhancing skills relative to participatory research and establishing these partnerships. Readings, lectures and problem-based learning activities will be used to improve principle investigators and partners' skills in participatory research. Principle investigators will establish community teams in their home state including (campus health experts, appropriate outreach/Extension partners and students). These teams will explore the participatory research process and will develop the best ways to proceed with the participatory research with their young adult population. Objective 2 Procedures Once participatory state community teams are established, qualitative and quantitative methods will be used to focus on identifying perceived health concerns and quality of life for the target population. An epidemiological/literature analysis of college students health (and the behavioral and environmental determinants) will be compiled to broaden understanding of their current and future health risks and trends. Focus groups will reveal and summarize the appropriate themes with samples 10-12 men and 10-12 women from each campus. Quality of life is characterized as how one defines their day-to-day and long-term goals, aspirations, frustrations, and stressors. This general quality of life assessment will later narrow to more specific health and educational concerns. Once all quality of life, health and educational concerns/themes are identified, a web-survey will be developed, pilot-tested and distributed to a sample of no less than 150 students per state. These results will be analyzed and evaluated. Community teams will prioritize the quality of life, health issues and behavioral and environmental determinants and will draft appropriate objectives. The results of the first survey (Quality of Life and Perceived Health) will guide the development of a second survey to assess the students predisposing (knowledge/attitudes), enabling (resources/skills) and reinforcing (support) factors associated with their quality of life and behavioral and environmental determinants of their health. This survey will also identify preferred modalities for potential interventions. This survey will be pilot tested and directed toward the same 150 students per state. There are numerous existing valid and reliable surveys that identify predisposing, enabling and reinforcing factors. Stage of Change and Eating Competence are two examples of the types of instruments that may be used. Community teams will conduct ecological/environmental analysis such as mapping of food outlets and the percentage of healthful options available, vending options and policies, the availability of transportation, and types of food vendors. State and community teams will collaborate throughout the process and will review the literature, quality of life/health and predisposing/enabling and reinforcing survey results, and ecological/environmental analysis to generate the most important needs identified by their population. Objective 3 Procedures This Administrative and Policy analysis is a review of the programs, interventions, resources, policies, environmental changes that could be used to address the needs identified in Objective 2. Campus teams will review the literature and existing weight/health programs. In addition, they will review the potential environmental and policy changes that could be implemented. This evaluation might include examples of locations which possess these positive environmental and policy initiatives for health and weight gain prevention. Objective 4 Procedures Partnership building activities will continue. Plans for preliminary studies will be developed cooperatively with the partners to meet needs identified by the partners/target population. Each state will develop intervention components in cooperation with partners and target population and develop a plan for testing intervention components and modalities with partners. Detailed and comprehensive plans for the intervention will be presented to the NC219 meeting by each state. These plans will be consolidated into a single document highlighting similarities and differences between states by the NC219 team. States will communicate through bi-monthly conference calls and will prepare a summary report for the annual NC 219 meeting. The focus will be on provision of preliminary intervention studies and initiation of funding requests in cooperation with the partnerships established in previous objectives.Measurement of Progress and Results
Outputs
- Each state will report frequency of contact with partners, how and when they completed their participatory research training and how they plan to achieve their CBPR objectives . States will communicate through bi-monthly conference calls and will prepare a summary report for the annual NC 219 meeting.
- Each state will prepare a report identifying the partner(s), frequency of contact with each partner, and perceived problems. Survey data will be evaluated and prioritized by each state/community team. Objectives will be generated for each PRECEDE-PROCEED phase by the state/community teams and consolidated by the NC219 group. These objectives will identify the quality of life, health, behavioral, environmental, predisposing, enabling and reinforcing effects desired by the intervention for the target population. States will communicate through bi-monthly conference calls and will prepare a summary report for the annual meeting identifying similarities and differences between states. Publications reporting results of qualitative work on perceived health concerns and quality of life concerns will be prepared and submitted for publication. Publications connecting quality of life, health and educational and environmental needs will be prepared and submitted.
- The community teams' work will be compiled into one large database.
- A report will define institutionalization progress and identify future plans
Outcomes or Projected Impacts
- Successful completion of the proposed Multistate Research Fund (MRF) project will have three important immediate impacts: 1) the cadre of researchers and extension educators working on the project will develop skill in using a new and promising research model - - community based participatory research (CBPR), 2) the usefulness of CBPR will be determined with a vulnerable population group - - young adult college students, and 3) the usefulness of a new approach to preventing weight gain - - the non-calorically restrictive, weight gain prevention intervention - - will be determined with this target audience. Success of this new approach to weight gain prevention could have a large impact on current and future weight gain prevention programs.
- In the long term, there is the potential for greater impacts. If the CBPR research model and/or the non-calorically restrictive, weight gain prevention intervention prove successful with young adult college students, these approaches can be adapted to meet the needs of more difficult to reach and more vulnerable young adult audiences - - non-students, low income people, ethnic minorities and parents. Studies with these audiences are more difficult to do and would require funding beyond that available through the MRF. The results of the proposed MRF project should provide a strong basis from which to compete for further funding.
Milestones
(1):ctober, 2006- September, 2007 Enhance participatory research skills. Establish partnerships with outreach educators and young adult populations. Initiate epidemiological literature review. Develop grant proposal(s).(2):ctober, 2007- September, 2008 Conduct qualitative and quantitative CBPR with partners/target population to identify health/quality of life problems and determinants. Compile and analyze data. Review and interpret results with community teams. Complete epidemiological literature review.
(3):ctober, 2008- September, 2009 Conduct quantitative CBPR to assess the predisposing, enabling and reinforcing factors determining the students health and quality of life. Conduct ecological/environmental analysis. Review results with community teams. Develop manuscript(s).
(4):ctober, 2008- September, 2009 Conduct administrative and policy analysis of existing programs, policies, and environmental strategies to meet identified needs. Develop plans for preliminary studies to test intervention components. Continue manuscript and grant proposal development.
(5):ctober, 2009- September, 2010 Continue planning and implementing selected intervention components in cooperation with partners. Process and analyze data. Continue manuscript and grant proposal development.
Projected Participation
View Appendix E: ParticipationOutreach Plan
Results will be disseminated through referred publicatons, non-referred but peer reviewed publications, and presentations at regional and national professional meetings.
Organization/Governance
The organizational structure consists of a chair and secretary nominated and elected annually by the technical committee. The chair will appoint subcommittees to complete the specific tasks. Conference calls will be held at minimum quarterly to address progress on project.
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