Insulin Resistance, Obesity, Stress
Conditions
Keywords
obesity, stress, intuitive eating, guided imagery, adolescents, insulin resistance, latinos, minorities
Brief summary
The childhood obesity epidemic, which falls disproportionately on Latino adolescents, represents a major public health threat to the current generation of youth, and therefore to the health of the nation overall. This project directly addresses the role of psychosocial stress in promoting obesity and metabolic disease risk, and investigates the role of the mind-body CAM intervention of guided imagery in both reducing stress and promoting healthy lifestyle behaviors that could dramatically improve the metabolic health of today's youth.
Detailed description
The childhood obesity epidemic represents a major health threat to the current generation of youth, and falls disproportionately on urban, Latino adolescents. Data suggests modern inner-city minority youth suffer from high levels of psychosocial stress, and that such chronic stress contributes to obesity and insulin resistance, increasing risk of type 2 diabetes, cardiovascular disease, fatty liver disease, and other obesity-related disorders. Guided imagery is a mind-body complementary/alternative medicine (CAM) modality that offers promise as a therapeutic intervention to reduce psychosocial stress, and also to promote healthy lifestyle behaviors. In a pilot 12-week lifestyle intervention, Interactive Guided ImagerySM significantly reduced salivary cortisol, reduced sedentary behavior, and increased moderate physical activity in overweight Latino adolescents. The overall aim of this proposal is to determine the separate contributions of stress reduction guided imagery and health behavior guided imagery, when delivered in the context of a health-promoting, lifestyle intervention, on short-term and long-term stress-reduction and behavioral outcomes in predominantly Latino high school students. The study consists of a high school-based, 12-week lifestyle intervention delivered in an after school program to urban, predominantly Latino adolescents. The intervention features a health-promoting, lifestyle education class, combined with a group guided imagery intervention that is theoretically grounded in Self-Determination Theory (SDT). High school students are randomized to one of 4 intervention arms 1) Non-intervention control; 2) lifestyle education alone (LS); 3) LS + Stress Reduction guided imagery alone; 4) LS + Physical Activity/Healthy Eating guided imagery. Outcomes will be measured upon completion of the 12-wk intervention, after an additional 6-month maintenance program, and after a further 6-month period of no program contact. Primary outcomes will be change in salivary cortisol patterns and changes in physical activity and dietary intake. Secondary outcomes are insulin resistance, body fat, carotid intima media thickness, metabolic syndrome, perceived stress, well-being (self-esteem, health related quality of life), and measures of mediation by SDT constructs. Results will demonstrate the isolated effects of the lifestyle education and the two different forms of guided imagery, and could shift the paradigm of obesity prevention and treatment in urban minority youth to include attention to social stress and promotion of well-being.
Interventions
BEHAVIORALLifestyle Education (LS)
See arm description
BEHAVIORALLS + Stress Reduction Guided Imagery
See Arm Description
BEHAVIORALLS + Activity/Eating Guided Imagery
See arm description
Sponsors
University of Southern California
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
HEALTH_SERVICES_RESEARCH
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
14 Years to 17 Years
Healthy volunteers
Yes
Inclusion criteria
* Male and female enrolled in second year (i.e. sophomore year) of high school at time of consent into study, junior year at time of intervention * Self-stated intent to complete high school * Predominantly minority ethnicity (self-reported) * Overweight/ obese and normal weight * Agreement to attend up to 3 after school classes per week for the 12 weeks of the program
Exclusion criteria
* Serious chronic illness or physical, cognitive, or behavioral disability that would prevent ability to fully receive intervention * Prior diagnosis of clinical eating disorder, psychiatric disorder, or significant cognitive disability * Lack of English fluency * Participation in previous Council programs offered through the school * Participation in formal weight-loss programs in 3 months preceding entry to study * Pregnancy * Sibling or other household member enrolling for the intervention
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Physical activity | 3 months | Physical activity and sedentary behavior will be measured by accelerometry and 3-day physical activity recall. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in Salivary Cortisol, daily slope | 3 months | Salivary cortisol will be collected on 3 successive days at awakening, 30-minutes post-awakening, and in the evening. |
| Change in Dietary intake | 3 months | Dietary intake of macronutrients measured by 3-day diet record |
Other
| Measure | Time frame | Description |
|---|---|---|
| Change in Insulin resistance | 3 months | The Homeostatic Model Insulin Resistance Index will be determined based on measures of fasting glucose and insulin. |
| Change in Carotid artery intima media thickness | 15 months | Determined by carotid artery ultrasound. |
| Change in Perceived Stress | 3 months | Measured by Perceived Stress Scale |
| Change in Intuitive eating | 3 months | Intuitive Eating Scale measures attitudes and behaviors relating to intuitive eating. |
| Change in Self-determination Theory Constructs | 3 months | Constructs of SDT will be assessed as theoretical mediators of intervention effects using the following survey measures: Perceived Competence for Participating in Regular Physical Activity (PCSPA) and for Healthy Eating (PCSHE); Health Care Climate Questionaire to determine autonomy support; Exercise Self-Regulation Questionnaire and Treatment Self-Regulation Questionnaire to determine autonomous motivation for physical activity and healthy eating; Group Cohesion Scale to assess relatedness. |
| Change in Well-Being | 3 months | Measured by Psychological General Well-Being Index (GWBS) and the Arizona Integrated Outcomes Scale. |
| Change in Adiposity | 3 months | BMI will be determined based on standards for age and sex, using clinical balance and stadiometer. Percent body fat will be determined by bioimpedance. |
Countries
United States
Outcome results
None listed