Comparing glycemic indicators of prediabetes: a prospective study of obese Latino Youth.

OBJECTIVE: One hour (1-hr) glucose during an oral glucose tolerance test (OGTT) is an emerging biomarker for type 2 diabetes. We compared the predictive power of 1-hr glucose to traditional glycemic markers for prospectively identifying prediabetes in youth. RESEARCH DESIGN AND METHODS: Obese normoglycemic Latino youth (N = 116) were assessed at baseline for glycated hemoglobin (HbA1c), fasting, 1-hr, and 2-hr glucose during an OGTT and were followed for up to 8 yr for the development of prediabetes. Receiver operating characteristic (ROC) curves were used and a multivariable prediction model was developed. RESULTS: The area under the 1-hr glucose ROC curve was the most powerful predictor of prediabetes over time [0.73, 95% confidence interval (CI) = 0.64-0.83]. However, combining all indicators into a single model was superior to individual marker models (0.77, 95% CI = 0.690.86). CONCLUSIONS: These results further support the utility of 1-hr glucose during an OGTT as a prospective marker of diabetes risk in youth.

Changes in Bone Biomarkers, BMC, and Insulin Resistance Following a 10-Week Whole Body Vibration Exercise Program in Overweight Latino Boys.

PURPOSE: With the childhood obesity epidemic, efficient methods of exercise are sought to improve health. We tested whether whole body vibration (WBV) exercise can positively affect bone metabolism and improve insulin/glucose dynamics in sedentary overweight Latino boys. METHODS: Twenty Latino boys 8-10 years of age were randomly assigned to either a control (CON) or 3 days/wk WBV exercise (VIB) for 10-wk. RESULTS: Significant increases in BMC (4.5 ± 3.2%; p=0.01) and BMD (1.3 ± 1.3%; p<0.01) were observed for the VIB group when compared to baseline values. For the CON group BMC significantly increased (2.0 ± 2.2%; p=0.02), with no change in BMD (0.8 ± 1.3%; p=0.11). There were no significant between group changes in BMC or BMD. No significant change was observed for osteocalcin and (collagen type I C-telopeptide) CTx for the VIB group. However, osteocalcin showed a decreasing trend (p=0.09) and CTx significantly increased (p<0.03) for the CON group. This increase in CTx was significantly different between groups (p<0.02) and the effect size of between-group difference in change was large (-1.09). There were no significant correlations between osteocalcin and measures of fat mass or insulin resistance for collapsed data. CONCLUSION: Although bone metabolism was altered by WBV training, no associations were apparent between osteocalcin and insulin resistance. These findings suggest WBV exercise may positively increase BMC and BMD by decreasing bone resorption in overweight Latino boys.

Imagine HEALTH: results from a randomized pilot lifestyle intervention for obese Latino adolescents using Interactive Guided ImagerySM.

BACKGROUND: There is an urgent need for innovative and developmentally appropriate lifestyle interventions to promote healthy lifestyle behaviors and to prevent the early onset of type 2 diabetes and cardiovascular disease risk in obese Latino adolescents. Guided imagery offers promise to reduce stress and promote lifestyle behavior change to reduce disease risk in obese adolescents. Our objectives were: 1) To pilot test a new 12-wk lifestyle intervention using a randomized trial design in obese Latino adolescents, in order to determine the effects of the mind-body modality of Interactive Guided ImagerySM (IGI), over and above those of a didactic lifestyle education, on insulin resistance, eating and physical activity behaviors, stress and stress biomarkers; and 2) To explore the role of intervention-related changes in stress and stress biomarkers on changes in metabolic outcomes, particularly insulin resistance. METHODS: Obese (BMI > 95th percentile), Latino adolescents (n = 35, age 14-17) were randomized to receive either 12 weekly sessions of a lifestyle education plus guided imagery program (GI), or lifestyle education plus a digital storytelling computer program (DS). Between-group differences in behavioral, biological, and psychological outcomes were assessed using unpaired T-tests and ANCOVA in the 29 subjects who completed the intervention. RESULTS: The GI group demonstrated significant reductions in leisure sedentary behavior (p < .05) and increases in moderate physical activity (p < .05) compared to DS group, and a trend toward reduced caloric intake in GI vs DS (p = .09). Salivary cortisol was acutely reduced by stress-reduction guided imagery (p < .01). There were no group differences in adiposity, insulin resistance, perceived stress, or stress biomarkers across the 12-week intervention, though decrease in serum cortisol over the course of the intervention was associated with improved insulin sensitivity (p = .03) independent of intervention group and other relevant co-variates. CONCLUSIONS: The improvements in physical activity and stress biomarkers following this pilot intervention support the role of guided imagery in promoting healthy lifestyle behavior change and reducing metabolic disease risk in obese Latino adolescent populations. Future investigations will be needed to determine the full effects of the Imagine HEALTH intervention on insulin resistance, stress, and stress biomarkers. TRIAL REGISTRATION: Clinicaltrials.gov Registry #: NCT01895595.

Double jeopardy: metabolic syndrome leads to increased sedentary behavior in peri-pubertal minority females.

While most studies have focused on investigating the preventive effects of physical activity on metabolic risk, the longitudinal impacts of metabolic syndrome (MetS) on activity levels is poorly understood. This study aims to examine the influence of MetS on initial activity levels and the trajectory of activity levels in Latina and African American female children over 12 months (n = 55, 9 ± 1 years). Metabolic measures, including fat and lean tissue mass by BodPod, fasting glucose, lipids, blood pressure, and waist circumference, were collected at baseline. Moderate-to-vigorous physical activity and sedentary behavior by accelerometry were collected on a quarterly basis. There were no significant differences in either initial activity levels by MetS status (Moderate-to-vigorous physical activity: 33 ± 12 mins/day for MetS, 48 ± 28 mins/day for Non-MetS, p = .12; sedentary behavior: 408 ± 57 mins/day for MetS, 421 ± 72 mins/day for Non-MetS, p = .67). Longitudinal declines in moderate-to-vigorous physical activity (p = .038) and increases in sedentary behavior (p = .003) were found. Daily sedentary behavior increased by 82.64 more minutes in youth with MetS than in those without over one year (p = .015). This study yields the first evidence of the adverse effect of MetS on sedentary behavior. Targeted intervention strategies to reduce progressive sedentariness evident in minority youth with MetS are warranted.

Mind- and Body-Based Interventions Improve Glycemic Control in Patients with Type 2 Diabetes: A Systematic Review and Meta-Analysis.

Aims/Hypothesis: Only 51% of patients with type 2 diabetes achieve the hemoglobin A1c (HbA1c) <7% target. Mind and body practices have been increasingly used to improve glycemic control among patients with type 2 diabetes, but studies show inconsistent efficacy. The authors conducted a systematic review and meta-analysis to assess the association between mind and body practices, and mean change in HbA1c and fasting blood glucose (FBG) in patients with type 2 diabetes. Methods: The authors conducted a literature search of Ovid MEDLINE, Embase, and ClinicalTrials.gov seeking through June 10, 2022, published articles on mind and body practices and type 2 diabetes. Two reviewers independently appraised full text of articles. Only intervention studies were included. Reviewers extracted data for meta-analysis. Restricted maximum likelihood random-effects modeling was used to calculate the mean differences and summary effect sizes. The authors assessed heterogeneity using Cochran's Q and I2 statistics. Funnel plots were generated for each outcome to gauge publication bias. Weighted linear models were used to conduct study-level meta-regression analyses of practice frequency. Results: The authors identified 587 articles with 28 meeting the inclusion criteria. A statistically significant and clinically relevant mean reduction in HbA1c of -0.84% (95% confidence interval [CI]: -1.10% to -0.58%; p < 0.0001) was estimated. Reduction was observed in all intervention subgroups: mindfulness-based stress reduction: -0.48% (95% CI: -0.72% to -0.23%; p = 0.03), qigong: -0.66% (95% CI: -1.18% to -0.14%; p = 0.01), and yoga: -1.00% (95% CI: -1.38% to -0.63%; p < 0.0001). Meta-regression revealed that for every additional day of yoga practice per week, the raw mean HbA1c differed by -0.22% (95% CI: -0.44% to -0.003%; p = 0.046) over the study period. FBG significantly improved following mind and body practices, with overall mean difference of -22.81 mg/dL (95% CI: -33.07 to -12.55 mg/dL; p < 0.0001). However, no significant association was found between the frequency of weekly yoga practice and change in FBG over the study period. Conclusions/Interpretation: Mind and body practices are strongly associated with improvement in glycemic control in patients with type 2 diabetes. The overall mean reduction in HbA1c and FBG was clinically significant, suggesting that mind and body practices may be an effective, complementary nonpharmacological intervention for type 2 diabetes. Additional analyses revealed that the mean decrease in HbA1c was greater in studies requiring larger number of yoga practice sessions each week.

Imagine HEALTH: Changes in diurnal salivary cortisol patterns following a 12-week guided imagery RCT lifestyle intervention in predominantly Latino adolescents.

OBJECTIVE: Alterations in diurnal salivary cortisol patterns have been linked to adverse metabolic health outcomes. We have previously shown that stress-reduction guided imagery (GI) can reduce salivary cortisol levels acutely. We now ask whether addition of GI into a 12-week lifestyle intervention designed to improve eating and physical activity behaviors can alter diurnal salivary cortisol patterns and perceived stress. METHODS: 232 adolescent participants (ages 14-17 years) were cluster randomized by school into one of four intervention arms: non-intervention Control (C; n = 51), Lifestyle (LS; n=61), Stress-Reduction GI (SRGI; n = 55), and Lifestyle Behavior GI (LBGI; n = 65). LS group received one nutrition and one physical activity class per week after-school for 12 weeks. SRGI and LBGI groups received same LS classes plus an additional weekly GI session. Salivary cortisol was assessed pre- and post-intervention on 3 days, 3 times daily, at awakening, 30-minutes post-awakening, and in the evening to determine Cortisol Awakening Response (CAR) and Diurnal Cortisol Slope (DCS). Perceived Stress Scale (PSS) was administered pre- and post-intervention. Mixed effects modeling was used for intent-to-treat analysis and sensitivity analysis was used for those participants adherent to intervention protocol. RESULTS: Analysis of 208 subjects with complete data showed a small between-group increase in CAR in LBGI vs C (p = 0.045, d=0.24), with no significant group differences among other intervention arms. There were no between group differences in change in DCS or change in PSS after 12-weeks. Amongst adherent participants, LBGI showed a small-moderate increase in CAR (p = 0.03, d=0.37), and moderate-large reduction in PSS (p = 0.02, d=-0.66) compared to C. There were no other between group differences in CAR, DCS, or PSS. CONCLUSION: LBGI led to an increase in CAR, and in adherent subjects, a decrease in PSS, suggesting GI may be a mind-body intervention that can affect both objective and subjective measures of the stress response. Whether changes in cortisol patterns in this population affect measures of mental or physical health remains to be determined.

Rapid Decline in ß-Cell Function and Increasing Adiposity Are Associated With Conversion to Type 2 Diabetes in At-Risk Latino Youth.

Youth-onset type 2 diabetes (T2D) is becoming increasingly prevalent, especially among Latino youth, and there is limited information on its pathophysiology and causative factors. Here, we describe findings from a longitudinal cohort study in 262 Latino children with overweight/obesity at risk of developing T2D with annual measures of oral and intravenous glucose tolerance (IVGTT), body composition, and fat distribution. Logistic binomial regression was used to identify significant predictors in those who developed T2D compared with matched control participants, and mixed-effects growth models were used to compare rates of change in metabolic versus adiposity measures between groups. Overall conversion rate to T2D at year 5 was 2% (n = 6). Rate of decline in disposition index (DI), measured with an IVGTT, over 5 years was three times higher in case patients (-341.7 units per year) compared with the extended cohort (-106.7 units per year) and 20 times higher compared with control participants (-15.2 units per year). Case patients had significantly higher annual increases in fasting glucose, hemoglobin A1c (HbA1c), waist circumference, and trunk fat, and there was an inverse correlation between rate of decline in DI and rates of increase in adiposity measures. T2D development in at-risk Latino youth is associated with a substantial and rapid decrease in DI that is directly correlated with increases in fasting glucose, HbA1c, and adiposity. ARTICLE HIGHLIGHTS: Youth-onset type 2 diabetes is becoming increasingly prevalent, especially among Latino youth, and there is limited information on its pathophysiology and causative factors. Overall conversion rate to type 2 diabetes over 5 years was 2%. In youth who converted to type 2 diabetes, disposition index decreased rapidly by 85% compared with that in patients who did not convert during the study period. There was an inverse correlation between rate of decline in disposition index and rates of increase in various adiposity measures.

Morning Serum Cortisol Is Uniquely Associated with Cardiometabolic Risk Independent of Body Composition in Latino Adolescents.

Background: Alterations in morning serum cortisol (MSC) have been associated with higher cardiometabolic risk. This finding has been documented primarily in populations with overweight or obesity; however, it has not been clearly established if obesity plays a requisite role in this relationship. This study seeks to extend earlier findings by examining whether body composition measures alter the relationship between MSC with glucose and insulin markers, blood pressure, and lipid parameters in Latino youth in middle adolescence. Methods: This cross-sectional study included 196 healthy adolescents (130F/66M; mean age: 16.4 ± 0.6 years; 95% Latino; mean body mass index, BMI: 24.3 ± 5.7) from Los Angeles, California. Morning cortisol, glucose, insulin, glycated hemoglobin, and lipids (triglycerides and high-density lipoprotein cholesterol) were assessed from a fasting blood sample. Sitting systolic and diastolic blood pressure was averaged from duplicate measures. Body composition measures included BMI and waist circumference, which were used as proxies for total body and abdominal adiposity, respectively. Triplicate measurements of weight and height were averaged for calculation of BMI; age- and sex-specific BMI z-score was used to classify into normal BMI or overweight/obese BMI status. Waist circumference was measured in duplicate and the average was used to classify participants into two strata: normal/healthy waist circumference (<90th percentile for age, sex, and ethnicity) and high waist circumference (≥90th percentile). Results: The primary findings were that higher MSC was associated with higher fasting glucose and systolic blood pressure after adjusting for age, sex, and BMI z-score (and/or waist circumference). BMI status or waist circumference status did not alter these relationships. Main Conclusion: Our results suggest that the relationships between hypothalamic-pituitary-adrenal axis function and certain cardiometabolic risk factors may be independent of adiposity. Future research is warranted to discover the contributors and underlying mechanisms of these relationships in adolescent populations. ClinicalTrials.gov identifier: NCT02088294.

Hemoglobin A1c above threshold level is associated with decreased ß-cell function in overweight Latino youth.

OBJECTIVE: To examine whether a hemoglobin A1c (HbA1c)-identified prediabetic state (HbA1c ≥ 6.0%-6.4%) is associated with decreased insulin sensitivity (SI) and ß-cell dysfunction, known factors in the pathogenesis of type 2 diabetes, in an overweight pediatric population. STUDY DESIGN: A total of 206 healthy overweight Latino adolescents (124 males and 82 females; mean age, 13.1 ± 2.0 years) were divided into 2 groups: lower risk (n=179), with HbA1c <6.0%, and higher risk (n=27), with HbA1c 6.0%-6.4%. Measurements included HbA1c, oral glucose tolerance testing, fasting and 2-hour glucose and insulin, SI, acute insulin response, and disposition index (an index of ß-cell function) by the frequently sampled intravenous glucose tolerance test with minimal modeling. Body fat was determined by dual-energy X-ray absorptiometry. RESULTS: Compared with the lower risk group, the higher risk group had 21% lower SI (1.21 ± 0.06 vs 1.54 ± 0.13; P<.05), 30% lower acute insulin response (928 ± 102 vs 1342 ± 56; P<.01), and a 31% lower disposition index (1390 ± 146 vs 2023 ± 83; P=.001) after adjusting for age and total percent body fat. CONCLUSION: These data provide clear evidence of greater impairment of ß-cell function in overweight Latino children with HbA1c 6.0%-6.4%, and thereby support the adoption of the International Expert Committee's HbA1c-determined definition of high-risk state for overweight children at risk for type 2 diabetes.

Health-related quality of life in adolescents with or at risk for type 2 diabetes mellitus.

OBJECTIVE: To evaluate how adolescents with or at risk for type 2 diabetes mellitus (T2DM) and their parent/guardians (parents) perceive adolescents' health-related quality of life. STUDY DESIGN: We interviewed overweight/obese, 12- to 18-year-old youth with T2DM, prediabetes, or insulin resistance and one parent from 5 US sites. Assessments included Pediatric Quality of Life Inventory (PedsQL), Health Utilities Index, family conflict, and diabetes burden. RESULTS: In 108 adolescents, diagnoses included 40.7% with T2DM, 25.0% with prediabetes, and 34.3% with insulin resistance. PedsQL summary score (SS) was higher in adolescents than parents (P=.02). Parents rated physical functioning lower than adolescents (P<.0001), but there were no differences in psychosocial health. Adolescent PedsQL SS did not differ with diagnosis, but was inversely associated with adolescent body mass index z-score (P=.0004) and family conflict (P<.0001) and associated with race/ethnicity (P<.0001). Number of adolescent co-morbidities (P=.007) and burden of diabetes care (P<.05) were inversely associated with parent PedsQL SS. There were no differences in the Health Utilities Index-Mark 3 multi-attribute utility score. CONCLUSIONS: Parents perceive their adolescents' physical functioning as more impaired than adolescents themselves. Contextual factors including severity of obesity, race/ethnicity, family conflict, and burden of diabetes care influence health-related quality of life. Family-based approaches to treatment and prevention of T2DM may benefit from increased attention to the biopsychosocial context.

Physical activity is related to insulin sensitivity in children and adolescents, independent of adiposity: a review of the literature.

In adults, there is evidence that physical activity effectively improves insulin sensitivity regardless of adiposity. Whether this is also the case in children and adolescents is less clear. Clarifying this matter may help to identify the best outcomes to target in exercise programs for these age groups, where changes in adiposity may not always be desirable or realistic. A review of the literature was conducted on studies that examined the relationships of physical activity, cardiorespiratory fitness and strength with insulin sensitivity independent of adiposity in children and adolescents. Experimental (intervention) and correlational (longitudinal and cross-sectional) studies on participants ages 18 years and younger were identified. A total of 42 studies were included in this review. Sample sizes in the studies ranged from 14 to 4955 participants, with individual ages ranging from 5 to 19 years. A significant relationship with insulin sensitivity existed in 78% of studies on physical activity, 69% of studies on cardiorespiratory fitness and 66% of studies on strength. In studies that examined both physical activity and cardiorespiratory fitness concurrently, evidence suggests that they are both correlated with insulin sensitivity independent of adiposity, especially when physical activity is at higher intensities. However, the strength of this relationship might be influenced by study design, measurement techniques and participant characteristics. This is the first review of its type to take research design into account and to examine study outcomes according to participant ethnicity, gender, age, pubertal status and weight status.

Effects of Group-delivered Stress-reduction Guided Imagery on Salivary Cortisol, Salivary Amylase, and Stress Mood in Urban, Predominantly Latino Adolescents.

OBJECTIVES: To determine acute effects of stress-reduction guided imagery delivered in group format on stress biomarkers salivary cortisol and salivary amylase, and on self-reported stress mood, in healthy, predominantly Latino adolescents. STUDY DESIGN: 111 adolescent participants (94% Latino), a subset from a large, randomized controlled lifestyle intervention to improve obesity-related health behaviors, received either 4 weekly lifestyle education sessions (Lifestyle group; LS) or the same weekly lifestyle education sessions plus an additional weekly stress-reduction guided imagery session delivered in group format (Guided imagery group; GI). Salivary cortisol, salivary amylase, and self-reported stress moods were assessed before and after sessions on intervention weeks 3 and 4. Statistics: Linear mixed effects models examined within- and between-session and group differences in pre- to post-session changes. RESULTS: Both groups showed decreases in salivary cortisol, 5% decrease in LS group and 32% in GI group (within-group differences all P < .05), with between-group difference in salivary cortisol of moderate size (P = .05; Cohen's d = .44). Within the GI group alone, salivary cortisol decrease was similar following either the lifestyle or GI sessions (P = .64). There were no statistically significant amylase changes within or between groups. All 5 individual stress moods declined by 27% to 46% in the GI group (all P < .05), while only 1 of the 5 declined in LS group. CONCLUSIONS: Group stress-reduction guided imagery reduces the stress biomarker salivary cortisol, as well as reducing subjective stress mood states, making it a viable modality for large scale stress-reduction interventions.

Pubertal changes of insulin sensitivity, acute insulin response, and ß-cell function in overweight Latino youth.

OBJECTIVE: To examine changes in insulin sensitivity (SI), compensatory acute insulin response (AIR), and ß-cell function/disposition index (DI) across puberty in overweight Latino boys and girls. STUDY DESIGN: Latino children (n = 253) were followed annually for up to 5 years. Longitudinal modeling was used to examine changes in SI, AIR, DI, and fasting and 2-hour glucose and insulin across Tanner stage. RESULTS: In boys, SI decreased in early puberty with a recovery by late puberty. The compensatory increase in AIR was appropriate in early maturation, but after Tanner stage 3, AIR declined by more than that predicted from the recovery in SI. For girls, SI decreased in early puberty and across all stages of maturation. In early maturation, there was an appropriate compensatory increase in AIR, but after Tanner stage 3, AIR decreased. Thus, DI deteriorated across puberty in boys and girls. CONCLUSIONS: In overweight Hispanic youth, compensatory changes in insulin secretion fails after Tanner stage 3 in both sexes, indicating ß-cell deterioration during this critical period of development, thus increasing risk for type 2 diabetes.

Subclinical atherosclerosis in Latino youth: progression of carotid intima-media thickness and its relationship to cardiometabolic risk factors.

OBJECTIVE: To assess carotid artery intima-media thickness (CIMT) change over 2 years in overweight Latino adolescents and examine its relationship to cardiometabolic risk. STUDY DESIGN: Seventy-two healthy overweight male and female Latino adolescents (mean age, 14.5 ± 1.7 years; mean body mass index, 31.5 ± 6.9 kg/m(2)) were evaluated at baseline and 2 years later for CIMT by high-resolution B-mode ultrasound, the metabolic syndrome and its features, body composition by dual-energy x-ray absorptiometry and magnetic resonance imaging, glucose/insulin measures by fasting blood, and oral and intravenous glucose tolerance tests. RESULTS: Baseline CIMT did not differ from 2-year follow-up; however, 38 participants increased CIMT (0.017 ± 0.003 mm; +2.8%) and 34 decreased or remained the same (-0.019 ± 0.002 mm; -3.1%). ANCOVA analyses showed that participants with CIMT progression had higher baseline low-density lipoprotein (LDL)-cholesterol and total cholesterol (91.3 ± 3.4 and 150.3 ± 3.9 mg/dL) compared with those with CIMT non-progression (78.1 ± 3.6 and 135.6 ± 4.2 mg/dL, P < .05), independent of sex, baseline CIMT, age, and height. In multivariate regression, LDL-cholesterol was the sole predictor of CIMT progression, but the effect was small (odds of CIMT progression increased by 3% for each 1 mg/dL higher baseline LDL-cholesterol; 95% CI, 1.004 to 1.006, P = .03). CONCLUSIONS: These results indicate a high variability in the magnitude of CIMT change in growing overweight Latino youth and support the use of LDL-cholesterol to assess subclinical atherosclerosis risk in this population.

The mediating role of emotional eating in the relationship between perceived stress and dietary intake quality in Hispanic/Latino adolescents.

Obesity rates have steadily increased over the past three decades, and large racial/ethnic disparities in childhood obesity rates-specifically for Hispanic/Latino youth-highlight the major need for identifying and examining key mechanisms of obesogenic behaviors for this at-risk population. This study investigates the relationship between stress and dietary quality in Hispanic/Latino adolescents and seeks to determine the mediating role of emotional eating as a behavioral mechanism. Baseline data from 169 adolescents enrolled in the Imagine HEALTH trial were used to investigate these relationships. Perceived stress and emotional eating were assessed with age-validated questionnaires, and dietary quality was measured via 24-hour recall dietary assessments (later calculated as individual Healthy Eating Index-2015 scores). Nonparametric bootstrapping was used to test the primary hypothesis that emotional eating partially or fully mediates the relationship between perceived stress and dietary quality in this sample, and to test the significance of the mediating effect. Results indicate that emotional eating partially mediates the relationship between perceived stress and dietary quality. The total effect of perceived stress scores on dietary quality scores was -0.24 (p = .006); the direct effect of perceived stress scores on dietary quality scores (controlling for emotional eating scores) was -0.16 (p = .107), and the mediating (indirect) effect of emotional eating was -0.09 (p = .001). The proportion of mediation was 0.36 (36%) (p = .008). This study identifies an important mechanism of obesogenic behavior and can be used to inform future obesity prevention and intervention strategies tailored for the Hispanic/Latino adolescent population.

The Acute Relationship between Affective States and Stress Biomarkers in Ethnic Minority Youths.

Background: Whether affective states acutely predict the hypothalamic-pituitary-adrenal (HPA) axis activities and whether energy balance-related behaviors moderate the affect-HPA axis relationship in obese youths are not well-understood. Methods: 87 mostly obese (94.3% obese) minority adolescents (mean: 16.3 ± 1.2 years old; 56.8% Latino and 43.2% African American) participated in a randomized crossover trial in an observation laboratory, where they received either high-sugar/low-fiber (HSLF) or low-sugar/high-fiber (LSHF) meals first and then crossed over in the next visit 2-4 weeks later. During each visit, they rated five affective states and provided a saliva sample every 30 min for the first 5 h and wore a waist-worn accelerometer. The association between the affect ratings and cortisol levels in the subsequent 30 min and the moderation effect of energy balance-related behavior were examined using multilevel models. Results: Within-person negative affect (ß = 0.02, p = 0.0343) and feeling of panic (ß = 0.007, p = 0.004) were acutely related to the subsequent cortisol level only during the HSLF condition. The time spent in moderate-to-vigorous physical activity did not moderate the acute relationship between affect and the subsequent cortisol level. Conclusions: Negative affect could be acutely related to heightened HPA axis activities in youths, but only when they were exposed to meals with high sugar and low fiber content. These results suggest that the meals' sugar and fiber content may modulate HPA axis reactivity to negative affect in youths.

Imagine HEALTH: Randomized Controlled Trial of a Guided Imagery Lifestyle Intervention to Improve Obesity-Related Lifestyle Behaviors in Predominantly Latinx Adolescents.

Introduction: To determine the effects of a novel lifestyle intervention combining lifestyle behavioral education with the complementary-integrative health modality of guided imagery (GI) on dietary and physical activity behaviors in adolescents. The primary aim of this study was to determine the incremental effects of the lifestyle education, stress reduction GI (SRGI), and lifestyle behavior GI (LBGI) components of the intervention on the primary outcome of physical activity lifestyle behaviors (sedentary behavior, light, moderate, and vigorous physical activity), as well as dietary intake behaviors, at the completion of the 12-week intervention. The authors hypothesized that the intervention would improve obesity-related lifestyle behaviors. Materials and Methods: Two hundred and thirty-two adolescent participants (aged 14-17 years, sophomore or junior year of high school) were cluster randomized by school into one of four intervention arms: nonintervention Control (C), Lifestyle education (LS), SRGI, and LBGI. After-school intervention sessions were held two (LS) or three (SRGI, LBGI) times weekly for 12 weeks. Physical activity (accelerometry) and dietary intake (multiple diet recalls) outcomes were assessed pre- and postintervention. Primary analysis: intention-to-treat (ITT) mixed-effects modeling with diagonal covariance matrices; secondary analysis: ad hoc subgroup sensitivity analysis using only those participants adherent to protocol. Results: ITT analysis showed that the Healthy Eating Index (HEI) increased in the LS group compared with C (p = 0.02), but there was no additional effect of GI. Among adherent participants, sedentary behavior was decreased stepwise relative to C in SRGI (d = -0.73, p = 0.004) > LBGI (d = -0.59, p = 0.04) > LS (d = -0.41, p = 0.07), and moderate + vigorous physical activity was increased in SRGI (d = 0.58, p = 0.001). Among adherent participants, the HEI was increased in LS and SRGI, and glycemic index reduced in LBGI. Conclusions: While ITT analysis was negative, among adherent participants, the Imagine HEALTH lifestyle intervention improved eating habits, reduced sedentary activity, and increased physical activity, suggesting that GI may amplify the role of lifestyle education alone for some key outcomes. Clinical Trials.gov ID: NCT02088294.

Persistence of the metabolic syndrome over 3 annual visits in overweight Hispanic children: association with progressive risk for type 2 diabetes.

OBJECTIVE: To examine an association between persistent metabolic syndrome (MetS) and the risk for type 2 diabetes in overweight Hispanic children. STUDY DESIGN: A total of 73 subjects (mean age, 11.0 +/- 1.7 years) from a longitudinal study were classified as Never (negative for MetS at all 3 annual visits), Intermittent (positive for MetS at 1 or 2 visits), or Persistent (positive for MetS at all 3 visits). Measures included dual-energy x-ray absorptiometry, magnetic resonance imaging, the 2-hour oral glucose tolerance test, and the frequently sampled intravenous glucose tolerance test. RESULTS: The Persistent group had a faster rate of fat mass gain than the Never group (20% vs 15% gain of baseline value; P < .05 for time *group interaction [time = visit]). Independent of body composition, the Persistent group increased by 70% in insulin incremental area under the curve, whereas the other groups decreased (P < .05 for time *group interaction). Despite no time *group interactions for insulin sensitivity, acute insulin response, or disposition index, the Persistent group maintained 43% lower insulin sensitivity (P < .01) and by visit 2 had a 25% lower disposition index (P < .05) compared with the Never group. CONCLUSIONS: Patients with persistent MetS had accelerated fat gain, increased insulin response to oral glucose, and decreased sensitivity and beta cell function, indicators of progressively greater risk for type 2 diabetes.

Guided Imagery Council: Feasibility, Acceptability, and Preliminary Effects of a Novel Group-Based Lifestyle Intervention in Predominantly Latino Adolescents.

BACKGROUND: The combination of higher stress and higher obesity rates suggests that Latino youth in the United States may be a population at particular risk for obesity-related adverse health outcomes. The objective of this article is to describe the feasibility, acceptability, and quantitative stress-related outcomes of a 6-week pilot lifestyle intervention using guided imagery (GI) council in order to reduce risk factors for obesity-related disease. METHODS: Seventeen urban, adolescents (12 females/5 males, 16 Latino, age 17 ± 1 years, grades 9-12, body mass index 22 ± 4) participated in the 6-week, after-school pilot intervention. The intervention consisted of three, 75-minute after-school sessions delivered weekly for 6 weeks. The 3 weekly sessions included 1 session each of nutrition education, physical activity education and practice, and GI delivered in council, a facilitated group process based on indigenous practices. Feasibility and acceptability were assessed by attendance and qualitative exit interview. Stress outcomes included salivary cortisol and perceived stress. RESULTS: The pilot intervention was found to be feasible to deliver in an after-school setting. The GI and council group format were well liked. A 31% reduction in salivary cortisol was observed following the stress-reduction GI sessions. Diurnal cortisol patterns did not change across the intervention, but change in perceived stress was correlated with change in cortisol awakening response. CONCLUSIONS: The intervention was feasible to deliver and highly acceptable. Acute reduction in salivary cortisol was seen following group GI, while no change was seen in daily cortisol patterns. These results support the development of a full 12-week intervention using GI council to reduce obesity-related disease risk.