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1.
Sci Total Environ ; 930: 172840, 2024 Jun 20.
Article in English | MEDLINE | ID: mdl-38685432

ABSTRACT

Exposure to per- and poly-fluoroalkyl substances (PFAS) is ubiquitous due to their persistence in the environment and in humans. Extreme weight loss has been shown to influence concentrations of circulating persistent organic pollutants (POPs). Using data from the multi-center perspective Teen-Longitudinal Assessment of Bariatric Surgery (Teen-LABS) cohort, we investigated changes in plasma-PFAS in adolescents after bariatric surgery. Adolescents (Mean age = 17.1 years, SD = 1.5 years) undergoing bariatric surgery were enrolled in the Teen-LABS study. Plasma-PFAS were measured at the time of surgery and then 6-, 12-, and 36 months post-surgery. Linear mixed effect models were used to evaluate longitudinal changes in plasma-PFAS after the time of bariatric surgery. This study included 214 adolescents with severe obesity who had available longitudinal measures of plasma-PFAS and underwent bariatric surgery between 2007 and 2012. Underlying effects related to undergoing bariatric surgery were found to be associated with an initial increase or plateau in concentrations of circulating PFAS up to 6 months after surgery followed by a persistent decline in concentrations of 36 months (p < 0.001 for all plasma-PFAS). Bariatric surgery in adolescents was associated with a decline in circulating PFAS concentrations. Initially following bariatric surgery (0-6 months) concentrations were static followed by decline from 6 to 36 months following surgery. This may have large public health implications as PFAS are known to be associated with numerous metabolic related diseases and the significant reduction in circulating PFAS in individuals who have undergone bariatric surgery may be related to the improvement of such metabolic related diseases following bariatric surgery.


Subject(s)
Bariatric Surgery , Environmental Pollutants , Humans , Adolescent , Male , Female , Longitudinal Studies , Environmental Pollutants/blood , Environmental Exposure/statistics & numerical data , Fluorocarbons/blood , Obesity, Morbid/surgery , Obesity, Morbid/blood
2.
Obesity (Silver Spring) ; 32(5): 1023-1032, 2024 May.
Article in English | MEDLINE | ID: mdl-38515392

ABSTRACT

OBJECTIVE: Dichlorodiphenyldichloroethylene (DDE), an obesogen accumulating in adipose tissue, is released into circulation with weight loss, although its impact is underexplored among adolescents. We tested the association using an integrative translational approach of epidemiological analysis among adolescents with obesity and in vitro measures exploring the impact of DDE on adipogenesis via preadipocytes. METHODS: We included 63 participants from the Teen-Longitudinal Assessment of Bariatric Surgery (Teen-LABS) cohort. We assessed 4,4'-DDE in visceral adipose tissue at surgery and BMI and waist circumference at surgery and 0.5, 1, 3, and 5 years after. We conducted longitudinal analysis to estimate the interaction on weight loss between DDE and time since surgery. In vitro analysis quantified adipogenic differentiation in commercial human preadipocytes exposed to 4,4'-DDE via fluorescent staining and imaging. RESULTS: A dose-response relationship was observed, with the low-exposure group having a greater reduction in BMI during the first year compared to higher-exposure groups and showing smaller regains compared to higher-exposure groups after the first year. In vitro analysis of preadipocytes treated with 4,4'-DDE during adipogenic differentiation for 12 days showed a concentration-dependent increase in lipid accumulation. CONCLUSIONS: DDE could contribute to weight trajectory among adolescents undergoing bariatric surgery, potentially mediated via promoted adipogenesis in preadipocytes.


Subject(s)
Adipogenesis , Bariatric Surgery , Body Mass Index , Dichlorodiphenyl Dichloroethylene , Intra-Abdominal Fat , Weight Loss , Humans , Adolescent , Male , Female , Intra-Abdominal Fat/metabolism , Longitudinal Studies , Pediatric Obesity/metabolism , Adipocytes/metabolism , Cohort Studies , Waist Circumference
3.
Pediatr Obes ; 19(5): e13105, 2024 May.
Article in English | MEDLINE | ID: mdl-38339799

ABSTRACT

INTRODUCTION: Whilst glucagon-like peptide-1 receptor agonists (GLP1-RAs) are effective for treating adolescent obesity, weight loss maintenance (WLM; preventing weight regain) remains a challenge. Our goal was to investigate appetite/satiety hormones and eating behaviours that may predict WLM with exenatide (a GLP1-RA) versus placebo in adolescents with severe obesity. METHODS: Adolescents who had ≥5% body mass index (BMI) reduction with meal replacement therapy were randomized to 52 weeks of once-weekly exenatide extended release or placebo. In this secondary analysis, eating behaviours and appetite/satiety regulation hormones post-meal replacement therapy (pre-randomization to exenatide or placebo) were evaluated as possible predictors of WLM. Percent change in BMI from randomization to 52 weeks served as the primary measure of WLM. RESULTS: The analysis included 66 adolescents (mean age 16.0 years; 47% female). Lower leptin response to meal testing was associated with greater WLM in terms of BMI percent change in those receiving exenatide compared to placebo (p = 0.007) after adjusting for sex, age and BMI. There were no other significant predictors of WLM. CONCLUSIONS: Prior to exenatide, lower leptin response to meals was associated with improved WLM with exenatide compared to placebo. The mostly null findings of this study suggest that GLP1-RA treatment may produce similar WLM for adolescents with obesity regardless of age, BMI, sex and eating behaviours.


Subject(s)
Diabetes Mellitus, Type 2 , Obesity, Morbid , Pediatric Obesity , Adolescent , Humans , Female , Male , Obesity, Morbid/drug therapy , Exenatide/therapeutic use , Leptin , Appetite , Pediatric Obesity/drug therapy , Weight Loss , Feeding Behavior , Hypoglycemic Agents , Diabetes Mellitus, Type 2/drug therapy
4.
World J Gastroenterol ; 30(4): 332-345, 2024 Jan 28.
Article in English | MEDLINE | ID: mdl-38313232

ABSTRACT

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is one of the most common chronic liver diseases in children and adolescents. NAFLD ranges in severity from isolated hepatic steatosis to nonalcoholic steatohepatitis (NASH), wherein hepatocellular inflammation and/or fibrosis coexist with steatosis. Circulating microRNA (miRNA) levels have been suggested to be altered in NAFLD, but the extent to which miRNA are related to NAFLD features remains unknown. This analysis tested the hypothesis that plasma miRNAs are significantly associated with histological features of NAFLD in adolescents. AIM: To investigate the relationship between plasma miRNA expression and NAFLD features among adolescents with NAFLD. METHODS: This study included 81 adolescents diagnosed with NAFLD and 54 adolescents without NAFLD from the Teen-Longitudinal Assessment of Bariatric Surgery study. Intra-operative core liver biopsies were collected from participants and used to characterize histological features of NAFLD. Plasma samples were collected during surgery for miRNA profiling. A total of 843 plasma miRNAs were profiled using the HTG EdgeSeq platform. We examined associations of plasma miRNAs and NAFLD features using logistic regression after adjusting for age, sex, race, and other key covariates. Ingenuity Pathways Analysis was used to identify biological functions of miRNAs that were associated with multiple histological features of NAFLD. RESULTS: We identified 16 upregulated plasma miRNAs, including miR-193a-5p and miR-193b-5p, and 22 downregulated plasma miRNAs, including miR-1282 and miR-6734-5p, in adolescents with NAFLD. Moreover, 52, 16, 15, and 9 plasma miRNAs were associated with NASH, fibrosis, ballooning degeneration, and lobular inflammation, respectively. Collectively, 16 miRNAs were associated with two or more histological features of NAFLD. Among those miRNAs, miR-411-5p was downregulated in NASH, ballooning, and fibrosis, while miR-122-5p, miR-1343-5p, miR-193a-5p, miR-193b-5p, and miR-7845-5p were consistently and positively associated with all histological features of NAFLD. Pathway analysis revealed that most common pathways of miRNAs associated with multiple NAFLD features have been associated with tumor progression, while we also identified linkages between miR-122-5p and hepatitis C virus and between miR-199b-5p and chronic hepatitis B. CONCLUSION: Plasma miRNAs were associated with NAFLD features in adolescent with severe obesity. Larger studies with more heterogeneous NAFLD phenotypes are needed to evaluate miRNAs as potential biomarkers of NAFLD.


Subject(s)
Circulating MicroRNA , MicroRNAs , Non-alcoholic Fatty Liver Disease , Obesity, Morbid , Child , Adolescent , Humans , Non-alcoholic Fatty Liver Disease/diagnosis , Non-alcoholic Fatty Liver Disease/genetics , Non-alcoholic Fatty Liver Disease/complications , Liver/pathology , Circulating MicroRNA/genetics , Circulating MicroRNA/metabolism , Obesity, Morbid/complications , Obesity, Morbid/surgery , Obesity, Morbid/metabolism , MicroRNAs/metabolism , Obesity/complications , Fibrosis , Inflammation/pathology
5.
Int J Obes (Lond) ; 48(4): 575-583, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38177697

ABSTRACT

OBJECTIVE: Metabolic and bariatric surgery (MBS) is associated with decreased bone mineral density (BMD) in adults. The long-term impact of MBS during adolescence on BMD is unknown. We report bone health status 5 to 11 years after Roux-en-Y gastric bypass (RYGB) and vertical sleeve gastrectomy (VSG) from the Teen-LABS study cohort. METHODS: Between 2016 and 2022, BMD was measured by dual energy x-ray absorptiometry (DXA) in 106 young adults who had undergone MBS as adolescents. Volumetric BMD by peripheral quantitative computed tomography was measured on a subset. Ninety-one controls who had not undergone MBS were recruited for comparison. RESULTS: In cases (RYGB: mean age 26.8 ± 1.9 years, mean BMI 42.1 ± 9.9 kg/m2, VSG: mean age 25.1 ± 2.1 years, mean BMI 37.1 ± 8.4 kg/m2), compared to controls (mean age 26.5 ± 2.7 years, mean BMI 40.2 ± 8.7 kg/m2) (age p < 0.001, BMI p = 0.02), adjusted mean DXA-BMD (g/cm2) of the RYGB (n = 58) and VSG (n = 48) groups were lower at the hip (-10.0% and -6.3%), femoral neck (-9.6% and -5.7%) and ultra-distal radius (-7.9% and -7.0%; all p < 0.001), respectively. DXA-BMD did not differ between RYGB and VSG groups. Trabecular volumetric BMD at the radius and tibia were lower in the RYGB (-30% and -26%) and VSG (-15% and -14%) groups compared to the control group (p < 0.001). Greater time since MBS was associated with lower BMD Z-scores at the hip (p = 0.05) and femoral neck (p = 0.045). Percent change in body mass index (BMI) from baseline or in the first year after MBS were not associated with bone measures at a median of 9.3 years post MBS. CONCLUSION: BMD, especially of the hip and femoral neck, was lower in young adults who underwent MBS during adolescence compared to matched peers who had not undergone MBS. BMD Z-scores of the femoral neck were inversely associated with time since MBS but were not associated with BMI change.


Subject(s)
Bariatric Surgery , Gastric Bypass , Obesity, Morbid , Humans , Adolescent , Young Adult , Adult , Bone Density , Obesity, Morbid/surgery , Gastric Bypass/methods , Absorptiometry, Photon
6.
Contemp Clin Trials ; 138: 107444, 2024 03.
Article in English | MEDLINE | ID: mdl-38219798

ABSTRACT

BACKGROUND: Severe obesity is a complex, chronic disease affecting nearly 9% of adolescents in the U.S. Although the current mainstay of treatment is lifestyle therapy, pediatric clinical practice guidelines recommend the addition of adjunct anti-obesity medication (AOM), such as phentermine and topiramate. However, guidance regarding when adjunct AOM should be started and how AOM should be used is unclear. Furthermore, an inherent limitation of current treatment guidelines is their "one-size-fits-all" approach, which does not account for the heterogeneous nature of obesity and high degree of patient variability in response to all interventions. METHODS: This paper describes the study design and methods of a sequential multiple assignment randomized trial (SMART), "SMART Use of Medications for the Treatment of Adolescent Severe Obesity." The trial will examine 1) when to start AOM (specifically phentermine) in adolescents who are not responding to lifestyle therapy and 2) how to modify AOM when there is a sub-optimal response to the initial pharmacological intervention (specifically, for phentermine non-responders, is it better to add topiramate to phentermine or switch to topiramate monotherapy). Critically, participant characteristics that may differentially affect response to treatment will be assessed and evaluated as potential moderators of intervention efficacy. CONCLUSION: Data from this study will be used to inform the development of an adaptive intervention for the treatment of adolescent severe obesity that includes empirically-derived decision rules regarding when and how to use AOM. Future research will test this adaptive intervention against standard "one-size-fits-all" treatments.


Subject(s)
Anti-Obesity Agents , Obesity, Morbid , Pediatric Obesity , Adolescent , Child , Humans , Anti-Obesity Agents/therapeutic use , Anti-Obesity Agents/pharmacology , Fructose/therapeutic use , Pediatric Obesity/drug therapy , Phentermine/therapeutic use , Topiramate/therapeutic use , Weight Loss , Randomized Controlled Trials as Topic
7.
Res Sq ; 2023 Sep 21.
Article in English | MEDLINE | ID: mdl-37790519

ABSTRACT

Objective: Metabolic and bariatric surgery (MBS) is associated with decreased bone mineral density (BMD) in adults. The long-term impact of MBS during adolescence on BMD is unknown. We report bone health status 5 to 11 years after Roux-en-Y gastric bypass (RYGB) and vertical sleeve gastrectomy (VSG) from the Teen-LABS study cohort. Methods: Between 2016 and 2022, BMD was measured by dual energy x-ray absorptiometry (DXA) in 106 young adults who had undergone MBS as adolescents. Volumetric BMD by peripheral quantitative computed tomography was measured on a subset. Ninety-one controls who had not undergone MBS were recruited for comparison. Results: Compared to controls, adjusted mean DXA-BMD of the RYGB (n = 58) and VSG (n = 48) groups were lower at the hip (-10.0% and - 6.3%), femoral neck (-9.6% and - 5.7%) and ultra-distal radius (-7.9% and - 7.0%; all p < 0.001), respectively. DXA-BMD did not differ between RYGB and VSG groups. Trabecular volumetric BMD at the radius and tibia were lower in the RYGB (-30% and - 26%) and VSG (-15% and - 14%) groups compared to the control group (p < 0.001). Greater time since MBS was associated with lower BMD Z-scores at the hip (p = 0.05) and femoral neck (p = 0.045). Percent change in body mass index (BMI) from baseline or in the first year after MSB were not associated with bone measures at a median of 9.3 years post MSB. Conclusion: BMD, especially of the hip and femoral neck, was lower in young adults who underwent MBS during adolescence compared to matched peers who had not undergone MBS. BMD Z-scores of the femoral neck decreased with time since MBS but were not associated with BMI change.

9.
Environ Sci Technol ; 57(40): 14817-14826, 2023 10 10.
Article in English | MEDLINE | ID: mdl-37756184

ABSTRACT

Animal studies have pointed at the liver as a hotspot for per- and polyfluoroalkyl substances (PFAS) accumulation and toxicity; however, these findings have not been replicated in human populations. We measured concentrations of seven PFAS in matched liver and plasma samples collected at the time of bariatric surgery from 64 adolescents in the Teen-Longitudinal Assessment of Bariatric Surgery (Teen-LABS) study. Liver:plasma concentration ratios were perfectly explained (r2 > 0.99) in a multilinear regression (MLR) model based on toxicokinetic (TK) descriptors consisting of binding to tissue constituents and membrane permeabilities. Of the seven matched plasma and liver PFAS concentrations compared in this study, the liver:plasma concentration ratio of perfluoroheptanoic acid (PFHpA) was considerably higher than the liver:plasma concentration ratio of other PFAS congeners. Comparing the MLR model with an equilibrium mass balance model (MBM) suggested that complex kinetic transport processes are driving the unexpectedly high liver:plasma concentration ratio of PFHpA. Intratissue MBM modeling pointed to membrane lipids as the tissue constituents that drive the liver accumulation of long-chain, hydrophobic PFAS, whereas albumin binding of hydrophobic PFAS dominated PFAS distribution in plasma. The liver:plasma concentration data set, empirical MLR model, and mechanistic MBM modeling allow the prediction of liver from plasma concentrations measured in human cohort studies. Our study demonstrates that combining biomonitoring data with mechanistic modeling can identify underlying mechanisms of internal distribution and specific target organ toxicity of PFAS in humans.


Subject(s)
Alkanesulfonic Acids , Bariatric Surgery , Environmental Pollutants , Fluorocarbons , Animals , Humans , Adolescent , Cohort Studies , Liver , Fluorocarbons/analysis
10.
Surg Obes Relat Dis ; 19(10): 1154-1161, 2023 10.
Article in English | MEDLINE | ID: mdl-37296018

ABSTRACT

BACKGROUND: Roux-en-Y gastric bypass (RYGB) among adolescents with obesity results in significant weight loss; however, depot-specific changes have been understudied. OBJECTIVE: We hypothesized that visceral adipose tissue (VAT) reduction in adolescents undergoing RYGB would be greater than other depots and associated with improvement in cardiometabolic risk factors. SETTING: Three specialized treatment centers in Sweden. METHODS: Fifty-nine adolescents underwent dual x-ray absorptiometry before surgery and at 1, 2, and 5 years after RYGB. Changes in body composition in multiple depots (total fat, lean body, gynoid fat, android fat, subcutaneous adipose tissue, and VAT) and cardiometabolic risk factors were assessed using multiple linear regression analysis and generalized estimating equations adjusting for age, sex, and baseline risk factor levels. Data are presented as percent change (95% CI) with regression models showing slopes and estimated P values. RESULTS: At 1 year post-RYGB, a significant reduction was observed across all body composition measures (P < .001) with the greatest reduction observed in VAT (-65.1% [-68.7, -61.8]). From year 1 to 5 years post-RYGB, a regain was observed in all depots except lean body mass (1.2% [.3, 2.7], P = .105). A sex-specific difference in overall trajectories was only observed in lean body mass with males consistently having higher mean levels. Change in VAT at 1 year correlated with change in triglycerides (slope: .21 mg/dL/kg, P = .034) and fasting plasma insulin (slope: 44 pmol/L/kg, P = .027). CONCLUSIONS: Adiposity measures all decreased after RYGB but poorly predicted change in cardiometabolic risk. Despite significant reductions at 1 year, a steady regain was observed out to 5 years, with values still well below baseline. Further research should consider control group comparison and extended follow-up.


Subject(s)
Gastric Bypass , Male , Female , Humans , Adolescent , Gastric Bypass/methods , Cardiometabolic Risk Factors , Tissue Distribution , Obesity/surgery , Body Fat Distribution
12.
Pediatr Obes ; 18(2): e12986, 2023 02.
Article in English | MEDLINE | ID: mdl-36263895

ABSTRACT

BACKGROUND: Meal replacement therapy (MRT) is a structured treatment that is effective for short-term weight reduction in adolescents with severe obesity. However, like other interventions, MRT response is variable. OBJECTIVE: The goal of the current study was to characterize the experience of adolescents with severe obesity participating in MRT. METHODS: Seventeen adolescents with severe obesity participated in semi-structured, individual interviews about their experience participating in MRT. The authors used a biopsychosocial model as the theoretical framework and data was analysed using Interpretive Phenomenological Analysis. A biopsychosocial model views an individual's health as a blend of biological characteristics, behavioural factors, and social conditions. RESULTS: Results showed that adolescents with severe obesity described three biopsychosocial factors that were central to their experience with MRT: (1) scheduling and planning, (2) social support and pressure, and (3) intrapersonal factors. Specifically, adolescents with severe obesity identified that planning ahead, social support, and intrapersonal changes (e.g. self-confidence) can promote engagement in MRT. On the other hand, unplanned schedule changes, social pressures, and different intrapersonal factors (e.g., taste preference) can make engagement challenging. CONCLUSIONS: Adolescents provided information on factors that supported or hindered their engagement in MRT, and themes were consistent with prior literature on health behaviour change. Overall, adolescents would recommend MRT to other teenagers who carry extra weight. Future research can use the rich information provided by adolescents with severe obesity to enhance and individualize treatment options.


Subject(s)
Obesity, Morbid , Humans , Adolescent , Obesity, Morbid/therapy , Obesity , Health Behavior , Social Support , Motivation
13.
J Am Heart Assoc ; 11(22): e026430, 2022 11 15.
Article in English | MEDLINE | ID: mdl-36326050

ABSTRACT

Background Microparticles and endothelial microparticles (EMPs) are implicated in accelerating cardiovascular disease (CVD); however, data in pediatrics are limited. We examined the relationship of microparticles and EMPs with adiposity and subclinical CVD risk measures in a pediatric population to determine their potential as biomarkers of CVD risk. Methods and Results A cross-sectional study of youth (n=280; ages 8-20 years) with a range of body mass index categories was used. Microparticles, EMPs, and activated EMPs were measured by flow cytometry. %Body fat and %visceral adipose tissue were measured by dual X-ray absorptiometry. Measures of arterial stiffness and vascular wall structure were obtained. Linear regression (with log-transformed outcomes) and logistic regression were used to evaluate associations and all results were exponentiated. Youth with overweight/obesity and severe obesity had 2.50 (95% CI, 1.56-4.01) and 3.42 (95% CI, 2.15-5.43) times the geometric means of the total number of microparticles, respectively, compared with those with normal weight. Youth with overweight/obesity and severe obesity had 1.97 (95% CI, 1.09-3.55) and 2.34 (95% CI, 1.31-4.19) times the geometric means of the total number of EMPs, respectively, compared with those with normal weight. There were positive associations between the levels of both microparticles and EMPs with higher adiposity measures and poor CVD risk measures. Youth with higher adiposity showed 1.84 times the odds of having high levels of activated EMPs (%) (odds ratio, 1.84; 95% CI, 1.08-3.14) compared with those with normal weight. Conclusions Levels of microparticles, EMPs, and activated EMPs were positively associated with adiposity and poor subclinical CVD risk in a pediatric population.


Subject(s)
Cardiovascular Diseases , Cell-Derived Microparticles , Obesity, Morbid , Humans , Adolescent , Child , Overweight , Cross-Sectional Studies , Cardiovascular Diseases/diagnosis , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/etiology , Endothelium, Vascular , Obesity/complications , Obesity/diagnosis , Obesity/epidemiology
14.
Leuk Res ; 121: 106924, 2022 10.
Article in English | MEDLINE | ID: mdl-35939888

ABSTRACT

Acute lymphoblastic leukemia, a heterogenous malignancy characterized by uncontrolled proliferation of lymphoid progenitors and generally initiated in utero, is the most common pediatric cancer. Although incidence of ALL has been steadily increasing in recent decades, no clear reason for this trend has been identified. Rising concurrently with ALL incidence, increasing maternal obesity rates may be partially contributing to increasing ALL prevelance. Epidemiological studies, including a recent meta-analysis, have found an association between maternal obesity and leukemogenesis in offspring, although mechanisms underlying this association remain unknown. Therefore, the purpose of this review is to propose possible mechanisms connecting maternal obesity to ALL risk in offspring, including changes to fetal/neonatal epigenetics, altered insulin-like growth factor profiles and insulin resistance, modified adipokine production and secretion, changes to immune cell populations, and impacts on birthweight and childhood obesity/adiposity. We describe how each proposed mechanism is biologically plausible due to their connection with maternal obesity, presence in neonatal and/or fetal tissue, observation in pediatric ALL patients at diagnosis, and association with leukemogenesis, A description of ALL and maternal obesity trends, a summary of epidemiological evidence, a discussion of the pathway from intrauterine environment to subsequent malignancy, and propositions for future directions are also presented.


Subject(s)
Obesity, Maternal , Pediatric Obesity , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Somatomedins , Adipokines , Child , Female , Humans , Infant, Newborn , Pediatric Obesity/complications , Pediatric Obesity/epidemiology , Precursor Cell Lymphoblastic Leukemia-Lymphoma/complications , Precursor Cell Lymphoblastic Leukemia-Lymphoma/etiology , Pregnancy
15.
Magn Reson Imaging ; 91: 16-23, 2022 09.
Article in English | MEDLINE | ID: mdl-35537665

ABSTRACT

Measurements of liver volume from MR images can be valuable for both clinical and research applications. Automated methods using convolutional neural networks have been used successfully for this using a variety of different MR image types as input. In this work, we sought to determine which types of magnetic resonance images give the best performance when used to train convolutional neural networks for liver segmentation and volumetry. Abdominal MRI scans were performed at 3 Tesla on 42 adolescents with obesity. Scans included Dixon imaging (giving water, fat, and T2* images) and low-resolution T2-weighted scout images. Multiple convolutional neural network models using a 3D U-Net architecture were trained with different input images. Whole-liver manual segmentations were used for reference. Segmentation performance was measured using the Dice similarity coefficient (DSC) and 95% Hausdorff distance. Liver volume accuracy was evaluated using bias, precision, intraclass correlation coefficient, normalized root mean square error (NRMSE), and Bland-Altman analyses. The models trained using both water and fat images performed best, giving DSC = 0.94 and NRMSE = 4.2%. Models trained without the water image as input all performed worse, including in participants with elevated liver fat. Models using the T2-weighted scout images underperformed the Dixon-based models, but provided acceptable performance (DSC ≥ 0.92, NMRSE ≤6.6%) for use in longitudinal pediatric obesity interventions. The model using Dixon water and fat images as input gave the best performance, with results comparable to inter-reader variability and state-of-the-art methods.


Subject(s)
Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Adolescent , Child , Humans , Image Processing, Computer-Assisted/methods , Liver/diagnostic imaging , Magnetic Resonance Imaging/methods , Neural Networks, Computer , Water
16.
Obesity (Silver Spring) ; 30(5): 1105-1115, 2022 05.
Article in English | MEDLINE | ID: mdl-35403350

ABSTRACT

OBJECTIVE: This study sought to evaluate the effect of 52 weeks of exenatide extended release (XR) on the maintenance of meal replacement therapy (MRT)-induced BMI reduction in adolescents with severe obesity. METHODS: In this randomized, double-blind, placebo-controlled trial, 100 participants aged 12 to 18 years with BMI ≥ 1.2 × 95th percentile were enrolled in a short-term MRT run-in phase. Those who achieved ≥5% BMI reduction during the run-in were then randomized to 52 weeks of exenatide XR 2.0 mg or placebo weekly. Both groups also received lifestyle therapy. The prespecified primary end point was mean percent change in BMI from randomization (post run-in) to 52 weeks in the intention-to-treat population. RESULTS: A total of 100 participants were enrolled, and 66 (mean age 16 = [SD 1.5] years; 47% female) achieved ≥5% BMI reduction with MRT and were randomized (33 to exenatide XR and 33 to placebo). From randomization (post run-in) to 52 weeks, mean BMI increased 4.6% and 10.1% in the exenatide XR and placebo groups, respectively. The placebo-subtracted exenatide XR treatment effect was -4.1% (95% CI: -8.6% to 0.5%, p = 0.078). CONCLUSIONS: Although not achieving statistical significance, exenatide XR, compared with placebo, may partly mitigate the propensity toward BMI rebound in adolescents who achieved initial weight loss with dietary intervention.


Subject(s)
Obesity, Morbid , Adolescent , Double-Blind Method , Exenatide/therapeutic use , Female , Humans , Hypoglycemic Agents/pharmacology , Hypoglycemic Agents/therapeutic use , Male , Obesity, Morbid/drug therapy , Treatment Outcome , Weight Loss
18.
Int J Obes (Lond) ; 46(2): 359-365, 2022 02.
Article in English | MEDLINE | ID: mdl-34718333

ABSTRACT

BACKGROUND: There are limited data comparing the relative associations of various BMI metrics with adiposity and cardiometabolic risk factors in youth. OBJECTIVE: Examine correlations of 7 different BMI metrics with adiposity, cardiometabolic risk factors, and biomarkers (i.e. blood pressure, waist circumference, cholesterol, leptin, insulin, high molecular weight adiponectin, high-sensitivity c-reactive protein (hsCRP)). METHODS: This was a cross-sectional analysis of youth in all BMI categories. BMI metrics: BMI z-score (BMIz), extended BMIz (ext.BMIz), BMI percentile (BMIp), percent of the BMI 95th percentile (%BMIp95), percent of the BMI median (%BMIp50), triponderal mass index (TMI), and BMI (BMI). Correlations between these BMI metrics and adiposity, visceral adiposity, cardiometabolic risk factors and biomarkers were summarized using Pearson's correlations. RESULTS: Data from 371 children and adolescents ages 8-21 years old were included in our analysis: 52% were female; 20.2% with Class I obesity, 20.5% with Class II, and 14.3% with Class III obesity. BMIp consistently demonstrated lower correlations with adiposity, risk factors, and biomarkers (r = 0.190-0.768) than other BMI metrics. The %BMIp95 and %BMIp50 were marginally more strongly correlated with measures of adiposity as compared to other BMI metrics. The ext.BMIz did not meaningfully outperform BMIz. CONCLUSION: Out of all the BMI metrics evaluated, %BMIp95 and %BMIp50 were the most strongly correlated with measures of adiposity. %BMIp95 has the benefit of being used currently to define obesity and severe obesity in both clinical and research settings. BMIp consistently had the lowest correlations. Future research should evaluate the longitudinal stability of various BMI metrics and their relative associations with medium to long-term changes in adiposity and cardiometabolic outcomes in the context of intervention trials.


Subject(s)
Adiposity/physiology , Body Mass Index , Cardiometabolic Risk Factors , Pediatric Obesity/blood , Adolescent , Biomarkers/analysis , Child , Cross-Sectional Studies , Female , Humans , Male , Minnesota , Pediatric Obesity/complications , Pediatric Obesity/physiopathology , Young Adult
19.
Child Obes ; 17(4): 257-262, 2021 06.
Article in English | MEDLINE | ID: mdl-34061621

ABSTRACT

Background: Studies examining the association between hedonic hunger, that is, having frequent thoughts about food in the absence of an energy deficit, and obesity in youth show mixed results. This may be due to the confounding effect of binge eating, which has been associated with both hedonic hunger and obesity. The purpose of this study was to determine the extent to which hedonic hunger is associated with obesity independent of binge eating in youth. Methods: Data for this cross-sectional study were collected from youth enrolled in a larger study of cardiovascular disease and obesity. Linear regression models were used to assess the association between hedonic hunger measured by Power of Food Scale (PFS) and binge eating measured by Eating Disorder Examination-Questionnaire, on percent of the 95th BMI percentile (BMIp95). Results: Among 269 participants (mean age 12.8 years), 16.4% endorsed binge eating. PFS was positively associated with BMIp95 with a difference in percent of BMIp95 of 5.9% [95% confidence interval (1.5-10.3), p = 0.009]. However, when binge eating was added to the model, the relationship between PFS and BMIp95 was no longer significant. Conclusion: Hedonic hunger, above and beyond binge eating, may not be associated with BMI. Future research should examine whether screening for and targeting binge eating rather than hedonic hunger in weight management care may have more impact on obesity outcomes. Clinical Trial Registration number: NCT01508598.


Subject(s)
Binge-Eating Disorder , Pediatric Obesity , Adolescent , Binge-Eating Disorder/epidemiology , Child , Cross-Sectional Studies , Eating , Feeding Behavior , Humans , Hunger , Pediatric Obesity/epidemiology
20.
J Am Heart Assoc ; 10(1): e018092, 2021 01 05.
Article in English | MEDLINE | ID: mdl-33372524

ABSTRACT

Background Circulating endothelial cells (CECs) reflect early changes in endothelial health; however, the degree to which CEC number and activation is related to adiposity and cardiovascular risk factors in youth is not well described. Methods and Results Youth in this study (N=271; aged 8-20 years) were classified into normal weight (body mass index [BMI] percentage <85th; n=114), obesity (BMI percentage ≥95th to <120% of the 95th; n=63), and severe obesity (BMI percentage ≥120% of the 95th; n=94) catagories. CEC enumeration was determined using immunohistochemical examination of buffy coat smears and activated CEC (percentage of vascular cell adhesion molecule-1 expression) was assessed using immunofluorescent staining. Cardiovascular risk factors included measures of body composition, blood pressure, glucose, insulin, lipid profile, C-reactive protein, leptin, adiponectin, oxidized low-density lipoprotein cholesterol, carotid artery intima-media thickness, and pulse wave velocity. Linear regression models examined associations between CEC number and activation with BMI and cardiovascular risk factors. CEC number did not differ among BMI classes (P>0.05). Youth with severe obesity had a higher degree of CEC activation compared with normal weight youth (8.3%; 95% CI, 1.1-15.6 [P=0.024]). Higher CEC number was associated with greater body fat percentage (0.02 per percentage; 95% CI, 0.00-0.03 [P=0.020]) and systolic blood pressure percentile (0.01 per percentage; 95% CI, 0.00-0.01 [P=0.035]). Higher degree of CEC activation was associated with greater visceral adipose tissue (5.7% per kg; 95% CI, 0.4-10.9 [P=0.034]) and non-high-density lipoprotein cholesterol (0.11% per mg/dL; 95% CI, 0.01-0.21 [P=0.039]). Conclusions Methods of CEC quantification are associated with adiposity and cardiometabolic risk factors and may potentially reflect accelerated atherosclerosis as early as childhood.


Subject(s)
Atherosclerosis , Cardiovascular Diseases , Endothelial Cells/metabolism , Obesity , Vascular Cell Adhesion Molecule-1/blood , Adiposity/physiology , Adolescent , Age of Onset , Atherosclerosis/blood , Atherosclerosis/diagnosis , Atherosclerosis/physiopathology , Biomarkers/blood , Body Mass Index , Cardiometabolic Risk Factors , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/metabolism , Cardiovascular Diseases/prevention & control , Child , Correlation of Data , Female , Humans , Immunohistochemistry , Intra-Abdominal Fat/metabolism , Male , Obesity/blood , Obesity/diagnosis , United States/epidemiology
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