Theoretical Mediators of Diabetes Risk and Quality of Life Following a Diabetes Prevention Program for Latino Youth With Obesity.

PURPOSE: This study tested self-efficacy and social support for activity and dietary changes as mediators of changes in type 2 diabetes related outcomes following a lifestyle intervention among Latino youth. SETTING AND INTERVENTION: Latino adolescents (14-16 years) with obesity (BMI% = 98.1 ± 1.4) were randomized to a 3-month intervention (n = 67) that fostered self-efficacy and social support through weekly, family-centered sessions or a comparison condition (n = 69). MEASURES: Primary outcomes included insulin sensitivity and weight specific quality of life. Mediators included self-efficacy, friend, and family social support for health behaviors. Data was collected at baseline, 3-months, 6-months, and 12-months. ANALYSIS: Sequential path analysis was used to examine mediators as mechanisms by which the intervention influenced primary outcomes. RESULTS: The intervention had a direct effect on family (ß = 0.33, P < .01) and friend social support (ß = 0.22, P < .001) immediately following the intervention (3-months). Increased family social support mediated the intervention's effect on self-efficacy at 6-months (ß = 0.09, P < .01). However, social support and self-efficacy did not mediate long-term changes in primary outcomes (P > .05) at 12-months. CONCLUSIONS: Family social support may improve self-efficacy for health behaviors in high-risk Latino youth, highlighting the important role of family diabetes prevention. Fostering family social support is a critical intervention target and more research is needed to understand family-level factors that have the potential to lead to long-term metabolic and psychosocial outcome in vulnerable youth.

Familism, Self-Esteem, and Weight-Specific Quality of Life Among Latinx Adolescents With Obesity.

OBJECTIVE: Obesity is a critical public health condition affecting Latinx adolescents and contributes to health disparities across the lifespan. Childhood and adolescent obesity is associated with reduced quality of life (QoL) and decreased self-esteem. The purpose of this study is to examine the role of cultural (e.g., familism) and psychosocial (e.g., self-esteem) factors as predictors of weight-specific QoL among Latinx adolescents with obesity. METHODS: Baseline data from 160 Latinx adolescents (ages 14-16 years) with obesity (BMI > 95th percentile for age and sex) who were recruited for a diabetes prevention intervention were used. Structural equation modeling tested the relationships between four latent constructs (familism, positive self-esteem, self-deprecation, and weight-specific QoL). RESULTS: The model tested paths from familism to positive self-esteem, self-deprecation, and weight-specific QoL, and paths from positive self-esteem and self-deprecation to weight-specific QoL. Higher familism was positively associated with positive self-esteem but not self-deprecation. In turn, positive self-esteem was positively associated with higher weight-specific QoL, whereas self-deprecation was negatively associated. Furthermore, there was an indirect effect of familism on QoL via positive self-esteem. CONCLUSIONS: These data shed light into specific cultural and psychosocial constructs that influence QoL among Latinx adolescents with obesity. This study suggests that familism and positive self-esteem can operate as protective factors associated with higher weight-specific QoL in Latinx adolescents with obesity; whereas self-deprecation may operate as a risk factor for lower weight-specific QoL.

Decreased GlycA after lifestyle intervention among obese, prediabetic adolescent Latinos.

BACKGROUND: Obese youth with prediabetes are at increased risk for premature morbidity and mortality through multiple mechanisms, including increased systemic inflammation. GlycA is a novel measure of systemic inflammation that predicts type II diabetes, cardiovascular events, and all-cause mortality in adults. OBJECTIVE: The purpose of the present study was to examine changes in GlycA after lifestyle intervention among obese, prediabetic Latino youth. METHODS: Obese, prediabetic Latino youth (n = 27; 15.5 ± 1.1 years, 13 males/14 females) completed a 12-week lifestyle intervention that included weekly nutrition education and 3 d/wk of moderate to vigorous physical activity. Prediabetes was characterized by an expanded definition of impaired glucose tolerance, using 2-hour glucose ≥120 mg/dL after an oral glucose tolerance test. GlycA was assessed at baseline and 12 weeks using nuclear magnetic resonance spectroscopy. RESULTS: After the lifestyle intervention, GlycA was significantly reduced (445.3 ± 51.3 µmol/L to 419.0 ± 50.0 µmol/L, P = .01) (mean ± standard deviation). Additional improvements were observed in multiple cardiovascular risk factors, including body mass index (BMI; 34.8 ± 5.0 kg/m2 to 34.0 ± 5.1 kg/m2, P < .001), total cholesterol (154.1 ± 30.3 mg/dL to 143.3 ± 29.1 mg/dL, P = .003), and 2-hour glucose (141.0 ± 13.2 mg/dL to 115.9 ± 31.4 mg/dL, P < .001). Decreases in GlycA were associated with decreases in 2-hour glucose (r = 0.49, P = .008) and BMI (r = 0.41, P = .03). CONCLUSION: These data are consistent with the hypothesis that lifestyle intervention might improve GlycA levels in obese, prediabetic adolescent Latinos, but randomized trial evidence is needed. Healthy lifestyle modifications among high-risk youth may decrease future risk of cardiometabolic disease through reducing systemic inflammation, in addition to improving traditional cardiovascular risk factors.

Effects of a Community-Based Diabetes Prevention Program for Latino Youth with Obesity: A Randomized Controlled Trial.

OBJECTIVE: This study examined the short- and long-term effects of a community-based lifestyle intervention among Latino youth with obesity. METHODS: Latino adolescents (14-16 years old) were randomized to a 3-month lifestyle intervention (n = 67) or comparison control (n = 69) and followed for 12 months. The intervention included weekly nutrition and health classes delivered to groups of families and exercise sessions (3 days/week) delivered to groups of adolescents. Comparison youth received laboratory results and general health information. Primary outcomes included insulin sensitivity and weight-specific quality of life (QoL) with secondary outcomes of BMI percentile (BMI%), waist circumference, and percent body fat. RESULTS: At 3 months, youth in the intervention group exhibited significant increases in insulin sensitivity (P < 0.05) and weight-specific QoL (P < 0.001), as well as reductions in BMI%, waist circumference, and percent body fat compared with controls. Increases in weight-specific QoL and reductions in BMI% and percent body fat remained significant at 12 months (P < 0.001), while changes in insulin sensitivity did not. In a subsample of youth with prediabetes at baseline, insulin sensitivity (P = 0.01), weight-specific QoL (P < 0.001), and BMI% (P < 0.001) significantly improved at 3 months. CONCLUSIONS: Lifestyle intervention can improve cardiometabolic and psychosocial health in a vulnerable population of Latino adolescents at high risk for developing type 2 diabetes.

Preventing diabetes in obese Latino youth with prediabetes: a study protocol for a randomized controlled trial.

BACKGROUND: Obese Latino adolescents are disproportionately impacted by insulin resistance and type 2 diabetes. Prediabetes is an intermediate stage in the pathogenesis of type 2 diabetes and represents a critical opportunity for intervention. However, to date, no diabetes prevention studies have been conducted in obese Latino youth with prediabetes, a highly vulnerable and underserved group. Therefore, we propose a randomized-controlled trial to test the short-term (6-month) and long-term (12-month) efficacy of a culturally-grounded, lifestyle intervention, as compared to usual care, for improving glucose tolerance and reducing diabetes risk in 120 obese Latino adolescents with prediabetes. METHODS: Participants will be randomized to a lifestyle intervention or usual care group. Participants in the intervention group will attend weekly nutrition and wellness sessions and physical activity sessions twice a week for six months, followed by three months of booster sessions. The overall approach of the intervention is framed within a multilevel Ecodevelopmental model that leverages community, family, peer, and individual factors during the critical transition period of adolescence. The intervention is also guided by Social Cognitive Theory and employs key behavioral modification strategies to enhance self-efficacy and foster social support for making and sustaining healthy behavior changes. We will test intervention effects on quality of life, explore the potential mediating effects of changes in body composition, total, regional, and organ fat on improving glucose tolerance and increasing insulin sensitivity, and estimate the initial incremental cost effectiveness of the intervention as compared with usual care for improving glucose tolerance. DISCUSSION: The proposed trial builds upon extant collaborations of a transdisciplinary team of investigators working in concert with local community agencies to address critical gaps in how diabetes prevention interventions for obese Latino youth are developed, implemented and evaluated. This innovative approach is an essential step in the development of scalable, cost-effective, solution oriented programs to prevent type 2 diabetes in this and other populations of high-risk youth. TRIAL REGISTRATION: NCT02615353, registered on June 8, 2016.

Culturally-grounded diabetes prevention program for obese Latino youth: Rationale, design, and methods.

BACKGROUND: Type 2 diabetes (T2D) disproportionately impacts Latino youth yet few diabetes prevention programs address this important source of health disparities. OBJECTIVES: To address this knowledge gap, we describe the rationale, design, and methodology underpinning a culturally-grounded T2D prevention program for obese Latino youth. The study aims to: 1) to test the efficacy of the intervention for reducing T2D risk, 2) explore potential mediators and moderators of changes in health behaviors and health outcomes and, 3) examine the incremental cost-effectiveness for reducing T2D risk. Latino adolescents (N=160, age 14-16) will be randomized to either a 3-month intensive lifestyle intervention or a control condition. The intervention consists of weekly health education delivered by bilingual/bicultural promotores and 3 moderate-to-vigorous physical activity (PA) sessions/week. Control youth receive health information and results from their laboratory testing. Insulin sensitivity, glucose tolerance, and weight-specific quality of life are assessed at baseline, 3-months, 6-months, and 12-months. We will explore whether enhanced self-efficacy and/or social support mediate improvements in nutrition/PA behaviors and T2D outcomes. We will also explore whether effects are moderated by sex and/or acculturation. Cost-effectiveness from the health system perspective will be estimated by the incremental cost-effectiveness ratio using changes in insulin sensitivity at 12-months. CONCLUSIONS: The results of this study will provide much needed information on how T2D prevention interventions for obese Latino youth are developed, implemented and evaluated. This innovative approach is an essential step in the development of scalable, cost-effective, solution oriented programs to prevent T2D in this and other high-risk populations.

Diabetes Prevention for Latino Youth: Unraveling the Intervention "Black Box".

The translation of research findings into sustainable health promotion and disease prevention programs in community settings remains a challenge. This report describes the process of substantiating a community-developed diabetes prevention program for Latino youth through research. Included are design considerations, measurement strategies, and the context through which the project is culturally grounded for relevance and fit within a local community. The process included (1) refining the program to include salient, stakeholder-identified behavioral components; (2) refining the collaborative effort to embrace the capacity for facilitating relevant behavior change on targeted health-related outcomes to enhance intervention effectiveness; and (3) including the accurate assessment of intervention efficacy via precise assessment of diabetes-related health outcomes. We explain the process of collaborating with community partners to enhance the cultural relevance and sustainability of intervention effects on both individuals and communities. We discuss the rationale for empirical support for academic-community collaborations that function in both a "top-down" and a "bottom-up" manner to advance the science and practice of sustainable and efficacious community health promotion.