Organ fat in Latino youth at risk for type 2 diabetes.

PURPOSE: Obesity in youth increases the risk for type 2 diabetes (T2D) and elevated abdominal adipose tissue and organ fat may be particularly deleterious. The purpose of this study was to examine associations among measures of adiposity including total, visceral, and organ fat (hepatic and pancreatic) and whether these measures were independently associated with glycemia in Latino youth at risk for diabetes. METHODS: Latino adolescents (47 boys and 32 girls, 13.7 ± 1.4 years) with obesity (BMIz 2.3 ± 0.3) were assessed for total fat by DXA and visceral and organ fat by 3 T magnetic resonance imaging. Glycemic indicators included HbA1c, fasting glucose (FG), and 2-h glucose (2-HrG) following an oral glucose tolerance test. Pearson correlations and stepwise linear regression analyses controlling for age and sex were used to examine independent associations between adiposity and glycemia. RESULTS: Total fat was associated with visceral (r = 0.66, p = 0.001) and hepatic fat (r = 0.34, p < 0.01) while visceral fat was associated with hepatic (r = 0.42, p < 0.001) and pancreatic fat (r = 0.36, p < 0.001). In stepwise linear regression analysis, hepatic and pancreatic fat were significant predictors of FG, explaining 4.7% and 5.2% of the variance, respectively (total R2  = 0.14, p = 0.02). Hepatic fat was the only significant predictor of 2-HrG explaining 9.9% of the variance in the model (total R2  = 0.12, p = 0.03). No measure of adiposity was retained as a significant predictor of HbA1c. CONCLUSION: Hepatic and pancreatic fat were the only adiposity measures independently associated with glycemia but the small amount of variance explained underscores the need for additional T2D biomarkers in high risk youth.

Communicating incidental and reportable findings from research MRIs: considering factors beyond the findings in an underrepresented pediatric population.

BACKGROUND: The application of advanced imaging in pediatric research trials introduces the challenge of how to effectively handle and communicate incidental and reportable findings. This challenge is amplified in underserved populations that experience disparities in access to healthcare as recommendations for follow-up care may be difficult to coordinate. Therefore, the purpose of the present report is to describe the process for identifying and communicating findings from a research MRI to low-income Latino children and families. METHODS: Latino adolescents (n = 86) aged 12-16 years old with obesity and prediabetes underwent a research MRI (3 Tesla Philips Ingenia®) as part of a randomized controlled diabetes prevention trial. The research MRIs were performed at baseline and 6 months to assess changes in whole-abdominal fat distribution and organ fat in response to the intervention. An institutional pathway was developed for identifying and reporting findings to participants and families. The pathway was developed through a collaborative process with hospital administration, research compliance, radiology, and the research team. All research images were reviewed by a board-certified pediatric radiologist who conveyed findings to the study pediatrician for determination of clinical actionability and reportability to children and families. Pediatric sub-specialists were consulted as necessary and a primary care practitioner (PCP) from a free community health clinic agreed to receive referrals for uninsured participants. RESULTS: A total of 139 images (86 pre- and 53 post-intervention) were reviewed with 31 findings identified and 23 deemed clinically actionable and reportable. The only reportable finding was severely elevated liver fat (> 10%, n = 14) with the most common and concerning incidental findings being horseshoe kidney (n = 1) and lung lesion (n = 1). The remainder (n = 7) were less serious. Of youth with a reportable or incidental finding, 18 had a PCP but only 7 scheduled a follow-up appointment. Seven participants without a PCP were referred to a safety-net clinic for follow-up. CONCLUSIONS: With the increased utilization of high-resolution imaging in pediatric research, additional standardization is needed on what, when, and how to return incidental and reportable findings to participants, particularly among historically underrepresented populations that may be underserved in the community. TRIAL REGISTRATION: Preventing Diabetes in Latino Youth, NCT02615353.

Yields and costs of recruitment methods with participant phenotypic characteristics for a diabetes prevention research study in an underrepresented pediatric population.

BACKGROUND/AIMS: Prediabetes and diabetes disproportionately impact Latino youth, yet few diabetes prevention programs have prioritized inclusion of this underrepresented population. This report describes the recruitment process, yields, associated costs, and phenotypic characteristics of Latino youth with obesity and prediabetes enrolled in a randomized controlled diabetes prevention study in the USA. METHODS: Recruitment efforts included referrals from clinics, community outlets, local media, and word of mouth with the goal of enrolling 120 Latino adolescents aged 12-16 with obesity (BMI > 95th percentile) and prediabetes. Prediabetes eligibility was determined by any of the following: HbA1c between 5.7 and 6.5%, fasting glucose between 100 and 125 mg/dL, or a 2-h glucose between 120 and 199 mg/dL following a 75-g oral glucose tolerance test (OGTT), but not meeting any of the diagnostic criteria for diabetes. Eligible participants were randomized 2:1 to either a 6-month community-based lifestyle intervention that included group nutrition and health education classes (1 day/week) and group exercise classes (2 days/week) or usual care control arm. Recruitment yields were determined by review of referral source in the study screening database. Recruitment costs were determined by an after-the-fact financial review of actual and in-kind costs. Participant phenotypic characteristics (i.e., demographics, anthropometrics, and biochemical data) were compared by recruitment strategy using a one-way ANOVA. RESULTS: Recruitment efforts covered 160 mile2 (414 km2) across 26 ZIP codes (postcode) in the Phoenix Metropolitan Area and yielded 655 referrals from clinics (n = 344), community (n = 143), media (n = 137), and word-of-mouth (n = 31). From this pool, 26% (n = 167) did not meet general, pre-screening eligibility criteria; 29% (n = 187) declined participation; and 10% (n = 64) were unable to be contacted. A total of 237 youth were invited to the clinical research unit to determine final eligibility. Following the OGTT, 52% (n = 122) met prediabetes criteria and 117 were subsequently randomized. Clinical recruitment yielded the highest number of referrals (53%; n = 344) while word-of-mouth yielded the highest proportion (35%; n = 11) of randomized participants per referred youth. There were no significant differences in anthropometric or biochemical measures among youth by recruitment strategy. Based upon final enrollment numbers, community recruitment was the costliest approach ($486/randomized participant) followed by clinical ($248/randomized participant) and media ($236/randomized participant). CONCLUSIONS: The ability to meet enrollment goals for a clinical trial of an underrepresented population required multiple recruitment strategies. Although strategies vary in yields and costs, it appears they produce similar phenotypical risk profiles of eligible youth. TRIAL REGISTRATION: ClinicalTrials.gov NCT02615353 . Registered on 26 November 2015.

Epicardial adipose thickness in youth with type 1 diabetes.

BACKGROUND AND OBJECTIVE: Epicardial adipose thickness (EAT) is increased in adults with type 1 diabetes (T1D) and is thought to contribute to cardiovascular disease (CVD) in this population. Given that CVD risk factors emerge early in life, the purpose of this study was to identify whether EAT is increased in pediatric patients with T1D compared with non-diabetic controls. METHODS: Anthropometric data, blood pressure (BP), and EAT were evaluated in 20 youth with T1D and 20 age, sex, and body mass index (BMI) matched healthy controls between the ages of 5 and 18 years. RESULTS: EAT was 18.5% higher among youth with T1D compared to healthy controls (1.65 ± 0.44 mm vs 1.37 ± 0.27 mm, P = .02). In the entire cohort, EAT was correlated with age (r = 0.71, P < .001), BMI (r = .69, P < .001), waist circumference (r = 0.60, P < .001), systolic BP (r = .34, P = .03), and diastolic BP (r = 0.41, P = .009). Among youth with T1D, there were no significant correlations between EAT and HbA1c (r = -0.16, P = .50), insulin dose (r = .09, P = .71), or duration of disease (r = 0.06, P = .82). CONCLUSIONS: Youth with T1D exhibited significantly higher EAT compared to controls. Increased EAT was associated with adiposity and BP, but not duration of disease, insulin dose, or glycemic control. Increased EAT may represent a pathophysiologic mechanism leading to premature CVD in pediatric patients with T1D.

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.