Changes in plasma concentrations of per- and Polyfluoroalkyl substances after bariatric surgery in adolescents from the Teen-Longitudinal Assessment of Bariatric Surgery (Teen-LABS) study

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.

Exposure to 4,4'-DDE in visceral adipose tissue and weight loss in adolescents from the Teen-LABS cohort

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.

Bone mineral density in young adults 5 to 11 years after adolescent metabolic and bariatric surgery for severe obesity compared to peers

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.

Cognitive function 10 years after adolescent bariatric surgery

BACKGROUND

Adolescent bariatric surgery produces substantial weight loss and reduction of medical co-morbidities. Research in adult samples shows improved cognitive function postoperatively, although much less is known about the potential cognitive benefits of bariatric surgery in adolescents-especially at extended follow-up.

OBJECTIVE

Examine cognitive function 10 years after adolescent bariatric surgery.

SETTING

University hospital.

METHODS

A total of 99 young adults who underwent bariatric surgery as adolescents completed a computerized cognitive test battery as part of a larger 10-year postoperative assessment. All had been long-term participants in the Teen-Longitudinal Assessment of Bariatric Surgery (Teen-LABS) study.

RESULTS

Cognitive dysfunction was prevalent on tests of attention and executive function (e.g., Continuous Performance Test - Reaction Time 30%; Maze Errors - Overrun 30%), and 53.5% met research criteria for mild cognitive impairment (MCI). Modified Poisson regression with robust error variance revealed participants with preoperative hypertension and those completing Roux-en-Y gastric bypass were more likely to meet criteria for MCI at 10-year follow-up.

CONCLUSIONS

The current findings indicate that cognitive deficits are common 10 years after bariatric surgery. Additional studies are needed to clarify possible cohort effects, determine whether these cognitive deficits persist to even later follow-up (e.g., 20 yr after surgery), and identify underlying mechanisms and mitigation strategies.

Paired Liver:Plasma PFAS Concentration Ratios from Adolescents in the Teen-LABS Study and Derivation of Empirical and Mass Balance Models to Predict and Explain Liver PFAS Accumulation

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.

Bone mineral density 5 to 11 years after metabolic and bariatric surgery in adolescents with severe obesity compared to peers

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.

The association of sagittal abdominal diameter with metabolic syndrome risk before and after weight-loss surgery in adolescents

BACKGROUND

Metabolic syndrome (MetS) affects ∼10% of U.S. adolescents. Abdominal obesity is the most prevalent component and may indicate MetS risk in adolescents undergoing weight loss surgery.

OBJECTIVES

Assess MetS risk/severity and its association with abdominal obesity (measured by sagittal abdominal diameter, SAD) before and after weight loss surgery in adolescents to determine whether SAD predicts MetS risk in this population.

SETTING

Data were collected in the Teen Longitudinal Assessment of Bariatric Surgery (Teen-LABS) study at 5 sites (U.S. children's hospitals) performing weight-loss surgery in adolescents. The current study is a secondary analysis of these data.

METHODS

We examined data collected presurgery through 5 years postsurgery. MetS risk/severity was defined using the MetS severity z score (MetS-z), and MetS prevalence was determined using age-appropriate criteria. Association between SAD and MetS-z was evaluated with an adjusted linear mixed model.

RESULTS

Among 228 individuals (75% female, 72% White), mean age 16.5 years and body mass index (BMI) 53 kg/m2, 79% met MetS criteria pre-urgery. MetS-z (1.5) and SAD (32cm) were correlated (r = 0.6, P < .0001) presurgery, and both improved significantly at 6 months, 1, and 5 years postsurgery, remaining highly correlated at each timepoint. SAD predicted MetS-z (β = 0.118; 95% CI, 0.109, 0.127) after adjustment for age, visit, surgery type, and caregiver education.

CONCLUSIONS

Abdominal obesity is a key MetS risk marker in youth undergoing weight loss surgery. Both SAD and Met-z measures may be useful for MetS risk assessment and tracking postsurgery changes in this population, but more research is needed to identify effective lifestyle interventions targeting abdominal obesity.

Novel clinical algorithm for hypothalamic obesity in youth with brain tumours and factors associated with excess weight gain

BACKGROUND

A standardized approach for identifying and treating hypothalamic obesity (HO) in children with hypothalamic tumours is lacking.

OBJECTIVES

To describe children with hypothalamic tumours at risk for obesity, assess outcomes of a novel HO clinical algorithm, and identify factors associated with weight gain.

METHODS

Retrospective analysis of youth with hypothalamic and suprasellar tumours, seen at a paediatric tertiary care centre from 2010 to 2020.

RESULTS

The study cohort (n = 130, 50% female, median age at diagnosis 5 [range 0-17]y) had a median duration of follow up of 5 (0.03-17)y. At last recorded body mass index (BMI) measurement, 34% had obesity, including 17% with severe obesity. Median onset of overweight and obesity after diagnosis was 6.2 (0.3-134) and 8.9 (0.7-65) months, respectively. After algorithm implementation (n = 13), the proportion that had an early dietitian visit (within 6 months) increased from 36% to 54%, (p = 0.498) and weight management referrals increased from 51% to 83% (p = 0.286). Higher BMI z-score at diagnosis was associated with overweight and obesity development (p < 0.001).

CONCLUSION

Patients with hypothalamic tumours commonly develop obesity. Use of a clinical algorithm may expedite recognition of HO. Further research is needed to identify predictors of weight gain and to develop effective treatment.

Multi-Institutional Quality Improvement Project to Minimize Opioid Prescribing in Children after Appendectomy Using NSQIP-Pediatric

BACKGROUND

There is wide variation in opioid prescribing after appendectomy in children and adolescents, with recent increases noted in opioid-related pediatric deaths from prescription and illicit opioids. The goal of this project was to minimize opioid prescribing at the time of discharge for children undergoing appendectomy by using Quality Improvement (QI) methodology.

STUDY DESIGN

Children (18 years of age or less) who underwent appendectomy were evaluated from January to December 2019 using NSQIP-Pediatric at 10 children's hospitals within the Western Pediatric Surgery Research Consortium. Before project initiation, 5 hospitals did not routinely prescribe opioids after appendectomy (protocol). At the remaining 5 hospitals, prescribing was not standardized and varied by surgeon (no-protocol). A prospective multi-institutional QI project was used to minimize outpatient opioid prescriptions for children after appendectomy. The proportion of children at each hospital receiving an opioid prescription at discharge was compared for 6 months before and after the intervention using chi-square analysis.

RESULTS

Overall, 1,524 children who underwent appendectomy were evaluated from January to December 2019. After the QI intervention, overall opioid prescribing decreased from 18.2% to 4.0% (p < 0.001), with significant decreases in protocol hospitals (2.7% vs 0.8%, p = 0.038) and no-protocol hospitals (37.9% vs 8.8%, p < 0.001). The proportion of 30-day emergency room visits did not change after the QI intervention (8.9% vs 9.9%, p = 0.54) and mean postintervention pain management satisfaction scores were high.

CONCLUSION

Opioid prescribing can be minimized in children after appendectomy without increasing emergency room visits or decreasing patient satisfaction. Furthermore, NSQIP-Pediatric can be used as a platform for multi-institutional collaboration for successful implementation of QI projects.

Association of diet quality, physical activity, and abdominal obesity with metabolic syndrome z-score in black and white adolescents in the US

BACKGROUND AND AIMS

Metabolic syndrome (MetS) affects ∼10% of adolescents and is associated with cardiometabolic disease risk. The most prevalent MetS component is abdominal obesity. Healthy diet and physical activity (PA) are inversely associated with abdominal obesity and may reduce MetS risk in youth. Our aim was to examine associations of diet, activity, and abdominal obesity with MetS z-score (MetS-z).

METHODS AND RESULTS

An analysis of National Health and Nutrition Examination Survey (NHANES) 2011-2016 data in adolescents was performed. Healthy Eating Index (HEI)- 2015 scores were calculated for diet quality, PA habits were used to determine alignment with national guidelines, and abdominal obesity was assessed by sagittal abdominal diameter (SAD). MetS-z represented severity or potential risk for MetS. Multivariable regression evaluated the relationships of HEI, SAD and PA with MetS-z. Among 1214 black and white adolescents, SAD was significantly associated with MetS-z [β (95% CI) = 0.17 (0.16, 0.19); P <0.0001] while HEI-2015 components showed associations with MetS-z overall (HEI total, dairy, and sodium scores), and by sex (total, refined grains, dairy for males; added sugar, protein, whole grains for females). Mean HEI-2015 score was 47.4/100 (51.6 using the population-ratio method), and the proportion of adolescents meeting national PA guidelines was 37.6%, yet PA was not a significant predictor of MetS-z.

CONCLUSIONS

US adolescents have poor diet quality and fewer than half meet PA guidelines. Strategies for preventing MetS and related conditions in adolescence should focus on weight management - specifically, abdominal fat reduction - with individualized diet counseling.

Diabetes Remission Status During Seven-year Follow-up of the Longitudinal Assessment of Bariatric Surgery Study

CONTEXT

Few studies have examined the clinical characteristics that predict durable, long-term diabetes remission after bariatric surgery.

OBJECTIVE

To compare diabetes prevalence and remission rates during 7-year follow-up after Roux-en-Y gastric bypass (RYGB) and laparoscopic gastric banding (LAGB).

DESIGN

An observational cohort of adults with severe obesity recruited between 2006 and 2009 who completed annual research assessments for up to 7 years after RYGB or LAGB.

SETTING

Ten US hospitals.

PARTICIPANTS

A total sample of 2256 participants, 827 with known diabetes status at both baseline and at least 1 follow-up visit.

INTERVENTIONS

Roux-en-Y gastric bypass or LAGB.

MAIN OUTCOME MEASURES

Diabetes rates and associations of patient characteristics with remission status.

RESULTS

Diabetes remission occurred in 57% (46% complete, 11% partial) after RYGB and 22.5% (16.9% complete, 5.6% partial) after LAGB. Following both procedures, remission was greater in younger participants and those with shorter diabetes duration, higher C-peptide levels, higher homeostatic model assessment of β-cell function (HOMA %B), and lower insulin usage at baseline, and with greater postsurgical weight loss. After LAGB, reduced HOMA insulin resistance (IR) was associated with a greater likelihood of diabetes remission, whereas increased HOMA-%B predicted remission after RYGB. Controlling for weight lost, diabetes remission remained nearly 4-fold higher compared with LAGB.

CONCLUSIONS

Durable, long-term diabetes remission following bariatric surgery is more likely when performed soon after diagnosis when diabetes medication burden is low and beta-cell function is preserved. A greater weight-independent likelihood of diabetes remission after RYGB than LAGB suggests mechanisms beyond weight loss contribute to improved beta-cell function after RYGB.Trial Registration clinicaltrials.gov Identifier: NCT00465829.

Transforming surgical morbidity and mortality into a systematic case review

BACKGROUND/PURPOSE

The surgical morbidity and mortality (M&M) conferences at a regional children's hospital achieved the goals of case by case peer review and education for trainees but provided limited data for trending and analysis. In 2019, an institution-wide effort was initiated to create an electronic case review system with the goals of improving event capture and real-time practice performance feedback. Surgical M&M was migrated to this structured case review format to provide a platform for surgical performance improvement.

METHODS

An online secure database was created with a 3-step classification system based on Clavien-Dindo severity score, peer review, and causality fishbone analysis. The data entered were available in an interactive dashboard. Retrospective tabulation of the 2018 M&M data was performed using the archived paper system used prior to 2019.

RESULTS

For the calendar year of 2019, the division of pediatric surgery captured and categorized 193 complications in the case review system. The capture rate was 50 per 1000 surgical procedures. For a similar time frame in 2018, the capture rate was 35 per 1000 surgical procedures. The dashboard provided run charts of the incidence and types of complications by procedure and by surgeon. Similar trend data were not available in 2018. The dashboard output has made possible the creation of (non- risk adjusted) individual surgeon performance reports. The output has been used to direct process improvement projects and educational content.

CONCLUSION

Creation of an online database with interactive dashboard has allowed surgical M&M to evolve into a systematic case review that greatly facilitates quality improvement efforts. This system increased the event capture rate and provided novel practice performance feedback, resulting in process improvement projects and educational objectives predicated on the trending data. These electronic reporting tools are now available to all surgical divisions and represent a transformative approach to surgical case review.

TYPE OF STUDY

Retrospective Historical control; Quality improvement.

LEVEL OF EVIDENCE

Level III.

408. Evaluation of the negative predictive value of the SARS-CoV-2 PCR respiratory assays in asymptomatic children undergoing surgery

Background

Universal pre-operative screening with SARS-CoV-2 PCR has been adopted by institutions to mitigate risk to healthcare workers (HCW) during aerosol-generating procedures such as intubation. However, there remains uncertainty regarding rates of false negative results and optimal sampling type. The objective was to determine the reliability of single, pre-operative SARS-CoV-2 testing from the nasopharynx in children undergoing general anesthesia.

Methods

Children < 18 years of age who underwent intubation for a procedure received pre-operative testing 24–48 hours prior with a nasopharyngeal (NP) swab or wash, in conjunction with intra-operative nasal wash (NW) and tracheal aspirate (TA) sampling. All paired samples underwent testing using the Simplexa DiaSorin platform or a modified Centers for Disease Control assay. Cohen’s Kappa was used for interrater reliability of each sample result. McNemar’s Test was used to compare result proportions by sample type. Positive and negative predictive values (PPV, NPV) were calculated based on the intraoperative NW as the reference standard. Analyses were conducted using SAS (v 9.4).

Results

We collected full sample sets from 364 children from April 14 to May 15; 66% of pre-operative samples were NP swabs. The median age was 6 years (IQR 2,13), 55% were male, 68% were white and 41% of children had a high-risk comorbidity. Most surgeries were conducted by general surgery (23%), followed by orthopedics (19%). Only 2.5% of children had respiratory symptoms, and 4.8% had a documented fever within a week of the procedure. SARS-CoV-2 positive samples occurred in 4/364 (1%) of pre-operative samples, 8/363 (2.2%) of intra-operative samples, and 8/348 (2.3%) of TA samples. The pre-operative test had 100% PPV and 99% NPV, and the TA had 100% PPV and 98.6% NPV (Table 1). There was very good agreement (Figure) between pre- and intraoperative upper respiratory sampling, with a Kappa of 0.66, (95% CI 0.35–0.97). There was no statistical difference in results by sample type.

Table 1. Comparison of intra-operative and pre-operative nasopharyngeal sample results, test characteristics and test concordance

Table 2. Comparison of intra-operative nasopharyngeal and tracheal aspirate sample results, test characteristics and test concordance

Figure 1 Percent agreement between pre-operative and intra-operative samples

Conclusion

There is a high PPV and NPV of pre-operative SARS-CoV-2 PCR testing among children undergoing anesthesia. These data can help inform guidelines regarding appropriate precautions for HCW performing high risk procedures in asymptomatic pediatric patients.

Disclosures

Suchitra Rao, MD, BioFire (Grant/Research Support) Samuel Dominguez, MD, PhD, BioFire (Consultant, Research Grant or Support)

NURS-12. MAKING SURVIVORS HEALTHIER: A MULTIDISCIPLINARY APPROACH TO HYPOTHALAMIC OBESITY

BACKGROUND

Pediatric survivors of hypothalamic/suprasellar tumors have significant morbidities that greatly impact their quality of life. Management of hypothalamic obesity has traditionally fallen between multiple subspecialties without a timely and comprehensive approach.

METHODS

A multidisciplinary group of key players from neuro-oncology, endocrinology, nutrition, neurosurgery, and bariatric surgery were identified. Through this collaboration, a clinical algorithm for early identification of and intervention for hypothalamic obesity was developed. The goal of the quality improvement process is to increase the number of encounters with a registered dietitian (RD) with earlier and more consistent referrals to a specialized, multidisciplinary weight management program [Lifestyle Medicine; (LM)] for counseling and pharmacologic interventions. Indications for referral to LM were BMI &gt;95th percentile, crossing &gt;2 BMI percentiles on growth curve and/or hyperphagia symptoms. A retrospective review of pediatric patients who have suprasellar/ hypothalamic tumors was also conducted. Data collected included demographics, tumor type, BMI, RD visit, and LM clinic referral/visit.

RESULTS

Fifty patients were identified for analysis six months following clinical algorithm institution. Thirty-three (66%) patients had craniopharyngioma, 15 (30%) had low-grade gliomas, and two (4%) had germ cell tumors. Thirty-three (66%) patients were noted to be obese (defined as BMI &gt;95th percentile) at review. The median BMI of the entire cohort was 93rd (range, 1st-137th) percentile. Thirty-four (68%) patients had been seen by an RD. Twenty-seven (82%) of the obese patients had been referred to LM.

CONCLUSIONS

The development and implementation of the process for hypothalamic obesity prevention and intervention will be discussed.

Influence of Weight Loss on Obesity-Associated Complications After Metabolic and Bariatric Surgery in Adolescents

OBJECTIVE

Following metabolic and bariatric surgery (MBS), most adolescents experience weight loss and improvement of many obesity-associated complications (OACs). The relationship between weight loss and remission of OACs after MBS in adolescents has not been well described.

METHODS

The Teen Longitudinal Assessment of Bariatric Surgery (Teen-LABS) is a multi-institutional prospective observational study of adolescents who underwent MBS between 2007 and 2012. Lower-weight-loss responders (LWLRs) were defined as having <20% total body weight loss (TBWL) and higher-weight-loss responders (HWLRs) were defined as having ≥20% TBWL at 5 years after MBS. The prevalence of OACs was compared at baseline and 5 years after MBS.

RESULTS

Both LWLRs (n = 114) and HWLRs (n = 78) lost significant weight within the first year following MBS; however, the TBWL at 5 years for the LWLRs was 8.6% ± 9.5% compared with 33.8% ± 9.2% for the HWLRs. Those in the HWLR group were more likely to experience durable remission of composite dyslipidemia at 5 years, whereas there were no differences between groups in remission rates of all other OACs.

CONCLUSIONS

Greater weight loss after MBS in adolescents was associated with greater remission of composite dyslipidemia; however, remission of other OACs was not dependent on major sustained weight loss.

Environmental chemical burden in metabolic tissues and systemic biological pathways in adolescent bariatric surgery patients: A pilot untargeted metabolomic approach

BACKGROUND

Advances in untargeted metabolomic technologies have great potential for insight into adverse metabolic effects underlying exposure to environmental chemicals. However, important challenges need to be addressed, including how biological response corresponds to the environmental chemical burden in different target tissues.

AIM

We performed a pilot study using state-of-the-art ultra-high-resolution mass spectrometry (UHRMS) to characterize the burden of lipophilic persistent organic pollutants (POPs) in metabolic tissues and associated alterations in the plasma metabolome.

METHODS

We studied 11 adolescents with severe obesity at the time of bariatric surgery. We measured 18 POPs that can act as endocrine and metabolic disruptors (i.e. 2 dioxins, 11 organochlorine compounds [OCs] and 5 polybrominated diphenyl ethers [PBDEs]) in visceral and subcutaneous abdominal adipose tissue (vAT and sAT), and liver samples using gas chromatography with UHRMS. Biological pathways were evaluated by measuring the plasma metabolome using high-resolution metabolomics. Network and pathway enrichment analysis assessed correlations between the tissue-specific burden of three frequently detected POPs (i.e. p,p'-dichlorodiphenyldichloroethene [DDE], hexachlorobenzene [HCB] and PBDE-47) and plasma metabolic pathways.

RESULTS

Concentrations of 4 OCs and 3 PBDEs were quantifiable in at least one metabolic tissue for > 80% of participants. All POPs had the highest median concentrations in adipose tissue, especially sAT, except for PBDE-154, which had comparable average concentrations across all tissues. Pathway analysis showed high correlations between tissue-specific POPs and metabolic alterations in pathways of amino acid metabolism, lipid and fatty acid metabolism, and carbohydrate metabolism.

CONCLUSIONS

Most of the measured POPs appear to accumulate preferentially in adipose tissue compared to liver. Findings of plasma metabolic pathways potentially associated with tissue-specific POPs concentrations merit further investigation in larger populations.

Excess skin problems among adolescents after bariatric surgery

BACKGROUND

Bariatric surgery results in significant and durable weight loss and improved health in severely obese adolescents. An important adverse consequence of the massive weight loss after bariatric surgery is excess skin and soft tissue. The prevalence and clinical characteristics of excess skin-related symptoms have been described in adults undergoing bariatric surgery but not in adolescents. Although the higher skin elasticity of adolescents may result in fewer excess skin problems compared with adults, this hypothesis remains untested.

OBJECTIVES

The purpose of the present study was to describe the natural history of excess skin and its associated complications among severely obese adolescents undergoing bariatric surgery.

SETTING

University Hospitals, United States.

METHODS

We evaluated data from the Teen-Longitudinal Assessment of Bariatric Surgery cohort, a prospective, multiinstitutional study of adolescents (13-19 yr) undergoing bariatric surgery. Abdominal pannus severity (graded 0-5) and excess skin symptoms were evaluated preoperatively and for the first 5 years after bariatric surgery.

RESULTS

Among the 217 study participants, 198 (90%) had an abdominal pannus and 16 (7%) reported pannus-related symptoms at the time of bariatric surgery. Preoperative symptoms included intertriginous infections (n = 12, 75%), recurrent cellulitis (n = 5, 31%), and superficial cutaneous ulcerations (n = 1, 6%). Participants with a higher pannus grade preoperatively experienced both a greater reduction in pannus severity (P < .0001) and a higher incidence of pannus-related symptoms (P = .002) postoperatively. Changes in pannus severity occurred during the first 24 months after bariatric surgery; mean pannus severity remained unchanged beyond 24 months.

CONCLUSIONS

Severely obese adolescents who undergo bariatric surgery often present with an abdominal pannus at the time of surgery with associated symptoms. Higher preoperative pannus grade is associated with more pannus related symptoms after surgery. Counseling about need for body contouring surgery should be considered in this group.

Lifestyle Factors Associated with Metabolic Syndrome Z-Score in US Adolescents

Objectives

Metabolic syndrome (MetS) is a cluster of abnormalities including abdominal obesity that increases risk for diabetes and cardiovascular disease. MetS affects ∼10% of US adolescents, but more may be at risk. The MetS severity z-score (MetS-z) is a continuous measure that may be useful for indicating MetS risk. Preventing at-risk adolescents from developing MetS may be achievable through changes in lifestyle factors such as diet and physical activity. Our objective was to evaluate the relationship of lifestyle-related factors with MetS-z in adolescents.

Methods

We performed a cross-sectional analysis of adolescents (12 to 19 y) from the National Health and Nutrition Examination Survey (NHANES) 2011–2016. MetS-z was calculated from sex- and race-specific equations developed for adolescents. Sagittal Abdominal Diameter (SAD, representing abdominal visceral fat) was obtained using NHANES standard procedures. Dietary intake was estimated via two 24-hour diet recall interviews and used to calculate the Healthy Eating Index (HEI)-2015 total (range 0–100) and component scores (range 0–10) indicating diet quality. Physical activity (PA, minutes/week of voluntary moderate or vigorous exercise) was reported by participants to trained interviewers and used to determine adherence to national PA guidelines of at least 60 min/day. Multivariable linear regression was used to evaluate the relationship of HEI scores, SAD and physical activity with MetS-z.

Results

Sample size was 1291 (49% female, 50% white) adolescents. Means (SEM) were: Age, 15.4 y (0.09); BMI z-score, 0.63 (0.04); MetS-z, −0.08 (0.03); SAD, 18.3 cm (0.14); and HEI score, 47.4 (0.46). Median min/week of PA was 178.5, with 30.4% of adolescents meeting PA guidelines. The final model (R2 = 0.53) included age, SAD (β = 0.17, P &lt; 0.0001), HEI score (β = −0.003, P = 0.09), and physical activity (β = −0.005, P = 0.69).

Conclusions

US adolescents consume a poor-quality diet and less than half meet physical activity guidelines, yet as a group they have a MetS z-score &lt;0, indicating low overall risk. SAD had a significant, positive association with MetS-z. While physical activity and diet were not significant in the model, results suggest the need for improvement of overall diet quality to potentially reduce risk of MetS and related chronic diseases in youth.

Funding Sources

None.

OR22-06 Bone Outcomes Following Sleeve Gastrectomy in Adolescents and Young Adults with Obesity Versus Non-Surgical Controls

Background: Sleeve gastrectomy is the most commonly performed weight loss surgery in adolescents with moderate-to-severe obesity. While studies in adults have reported on the deleterious effects of gastric bypass surgery on bone structure and strength estimates, data are lacking for the impact of sleeve gastrectomy on these measures in adolescents.

Objective: To evaluate the impact of sleeve gastrectomy on bone outcomes in adolescents and young adults over 12 months using dual energy x-ray absorptiometry (DXA) and high resolution peripheral quantitative computed tomography (HRpQCT).

Participants and Methods: We enrolled 33 youth 14-22 years old with moderate to severe obesity; 17 underwent sleeve gastrectomy and 16 were followed without surgery. DXA was used to assess areal bone mineral density (aBMD). HRpQCT was used to assess bone geometry, microarchitecture and volumetric BMD (vBMD) and finite element analysis to assess strength estimates (stiffness and failure load) at the distal tibia and distal radius at baseline and 12 months. 25(OH) vitamin D (25OHD) levels were obtained at baseline and follow-up.

Results: The surgical group lost 28.2% of total body weight compared to 1.4% in the non-surgical group. The groups did not differ for changes in 25OHD levels (P=0.181). After controlling for age and sex, compared to the non-surgical group, the surgical group had reductions in aBMD Z-scores at the femoral neck and total hip (p≤ 0.0005). At the distal tibia, there were reductions in cortical thickness and trabecular number, and increases in trabecular separation and cortical vBMD, without changes in strength estimates in the surgical group vs. controls (p≤0.043). Changes were less marked at the distal radius. While sleeve gastrectomy resulted in deleterious effects on most bone parameters, there was an increase in cortical vBMD at both sites, possibly from a decrease in cortical porosity. Most differences were attenuated after adjusting for changes in BMI over 12 months.

Conclusions: Over 12 months, weight loss associated with sleeve gastrectomy in adolescents had deleterious effects on areal BMD, bone geometry and trabecular microarchitecture at weight-bearing sites. However, strength estimates did not decrease, possibly because of a simultaneous increase in cortical volumetric BMD. Additional research is necessary to determine the relative contribution(s) of weight loss and the metabolic effects of surgery, and whether the observed effects on bone stabilize or progress over time.

Bone outcomes following sleeve gastrectomy in adolescents and young adults with obesity versus non-surgical controls

BACKGROUND

Sleeve gastrectomy is the most commonly performed weight loss surgery in adolescents with moderate-to-severe obesity. While studies in adults have reported on the deleterious effects of gastric bypass surgery on bone structure and strength estimates, data are lacking for the impact of sleeve gastrectomy on these measures in adolescents.

OBJECTIVE

To evaluate the impact of sleeve gastrectomy on bone outcomes in adolescents and young adults over 12 months using dual energy X-ray absorptiometry (DXA) and high resolution peripheral quantitative computed tomography (HRpQCT).

PARTICIPANTS AND METHODS

We enrolled 44 youth 14-22 years old with moderate to severe obesity; 22 underwent sleeve gastrectomy and 22 were followed without surgery (16 females and 6 males in each group). At baseline and 12 months, DXA was used to assess areal bone mineral density (aBMD), HRpQCT of the distal radius and tibia was performed to assess bone geometry, microarchitecture and volumetric BMD (vBMD), and finite element analysis to assess strength estimates (stiffness and failure load). These analyses were adjusted for age, sex, race and the bone measure at baseline. Fasting blood samples were assessed for calcium, phosphorus, and 25(OH) vitamin D (25OHD) levels.

RESULTS

Over 12-months, the surgical group lost 27.2% of body weight compared to 0.1% in the non-surgical (control) group. Groups did not differ for changes in 25OHD levels (p = 0.186). Compared to controls, the surgical group had reductions in femoral neck and total hip aBMD Z-scores (p ≤ 0.0006). At the distal tibia, compared to controls, the surgical group had reductions in cortical area and thickness and trabecular number, and increases in trabecular area and separation (p ≤ 0.026). At the distal radius, the surgical group had greater reductions in trabecular vBMD, than controls (p = 0.010). The surgical group had an increase in cortical vBMD at both sites (p ≤ 0.040), possibly from a decrease in cortical porosity (p ≤ 0.024). Most, but not all, differences were attenuated after adjusting for 12-month change in BMI. Groups did not differ for changes in strength estimates over time, except that increases in tibial stiffness were lower in the surgical group (p = 0.044) after adjusting for 12-month change in BMI.

CONCLUSIONS

Over 12 months, weight loss associated with sleeve gastrectomy in adolescents had negative effects on areal BMD and certain HRpQCT parameters. However, bone strength estimates remained stable, possibly because of a simultaneous decrease in cortical porosity and increase in cortical volumetric BMD. Additional research is necessary to determine the relative contribution(s) of weight loss and the metabolic effects of surgery on bone outcomes, and whether the observed effects on bone stabilize or progress over time.

Thermic effect of food and resting energy expenditure after sleeve gastrectomy for weight loss in adolescent females

BACKGROUND

Few studies have addressed the effect of bariatric surgery on factors related to energy balance, including resting energy expenditure (REE) and thermic effect of food (TEF). To our knowledge, very few studies have examined changes in REE and none have investigated modifications in TEF after sleeve gastrectomy (SG) performed in adolescents.

OBJECTIVE

To assess energy expenditure in females who underwent SG as adolescents and matched-control participants as preliminary data about the potential of SG to confer differences in postprandial energy expenditure.

SETTING

Children's Hospital Medical Center, Cincinnati, Ohio, United States.

METHODS

In this observational study, REE and respiratory quotient (RQ) were measured via indirect calorimetry, followed by a standardized meal and assessment of TEF and postprandial RQ. Plasma drawn before and every 15 minutes after the meal was assayed for insulin, glucose, and C-peptide. Usual dietary intake was estimated using 24-hour recall interviews.

RESULTS

Fasting REE and RQ were similar between surgical and control groups. Postmeal TEF also did not differ between groups. The surgical group had higher RQ early in the postprandial period, whereas the control group RQ was higher after 125 minutes post meal. Compared with the control group, the surgical group had lower postprandial glucose, higher insulin and C-peptide, and consumed less daily energy during usual intake.

CONCLUSIONS

Postprandial RQ was consistent with the rapid gastric emptying typical of SG, yet we observed no group differences in REE or TEF. These findings may have been due to limited statistical power. More comprehensive studies of EE after SG are warranted.

Gastrointestinal symptoms in relation to quality of life after metabolic surgery in adolescents

BACKGROUND

Adolescent obesity is associated with significant co-morbidities, including decreased quality of life (QOL). QOL improves after metabolic and bariatric surgery (MBS), but recent studies have demonstrated that certain gastrointestinal symptoms (GIS) worsen after surgery, including reflux symptoms, nausea, bloating, and diarrhea.

OBJECTIVE

The aim of this study was to evaluate QOL and the effect of these symptoms on QOL after bariatric surgery.

SETTING

Five academic centers that perform adolescent MBS in the United States.

METHODS

We prospectively studied 228 adolescents undergoing MBS using the Teen-Longitudinal Assessment of Bariatric Surgery cohort. GIS and QOL scores were assessed before surgery, at 6 months, and yearly to 5 years after surgery. Analysis involved linear models examining QOL and the association between GIS and QOL adjusting for a priori determined covariates.

RESULTS

Adjusting for body mass index change over time, the physical component score (PCS) of the Short Form-36 (SF-36) increased after surgery from 44.2 at baseline to 54.4 at 5 years (P < .0001). The mental component score did not significantly change over time. The SF-36 domains that showed the biggest increase after surgery were physical functioning, physical role functioning, and general health. The SF-36 PCS decreased significantly over time post surgery in those with GIS of reflux, nausea, and diarrhea but remained higher than baseline SF-36 PCS. There was no statistically significant change in mental component score or impact of weight on quality of life-KIDS scores in those with or without GIS.

CONCLUSION

QOL, specifically the SF-36 PCS, increases after MBS. Reflux symptoms, nausea, and diarrhea reduce the degree of improvement in QOL in adolescents after MBS. Patients should be monitored and treated for these symptoms to address this decreased QOL.

Effect of Surgical Versus Medical Therapy on Diabetic Kidney Disease Over 5 Years in Severely Obese Adolescents With Type 2 Diabetes

OBJECTIVE

To compare diabetic kidney disease (DKD) rates over 5 years of follow-up in two cohorts of severely obese adolescents with type 2 diabetes (T2D) undergoing medical or surgical treatment for T2D.

RESEARCH DESIGN AND METHODS

A secondary analysis was performed of data collected from obese participants of similar age and racial distribution enrolled in the Teen-Longitudinal Assessment of Bariatric Surgery (Teen-LABS) and the Treatment Options of Type 2 Diabetes in Adolescents and Youth (TODAY) studies. Teen-LABS participants underwent metabolic bariatric surgery (MBS). TODAY participants were randomized to metformin alone or in combination with rosiglitazone or intensive lifestyle intervention, with insulin therapy given for glycemic progression. Glycemic control, BMI, estimated glomerular filtration rate (eGFR), urinary albumin excretion (UAE), and prevalence of hyperfiltration (eGFR ≥135 mL/min/1.73 m²) and elevated UAE (≥30 mg/g) were assessed annually.

RESULTS

Participants with T2D from Teen-LABS (n = 30, mean ± SD age, 16.9 ± 1.3 years; 70% female; 60% white; BMI 54.4 ± 9.5 kg/m²) and TODAY (n = 63, age 15.3 ± 1.3 years; 56% female; 71% white; BMI 40.5 ± 4.9 kg/m²) were compared. During 5 years of follow-up, hyperfiltration decreased from 21% to 18% in Teen-LABS and increased from 7% to 48% in TODAY. Elevated UAE decreased from 27% to 5% in Teen-LABS and increased from 21% to 43% in TODAY. Adjusting for baseline age, sex, BMI, and HbA_1c, TODAY participants had a greater odds of hyperfiltration (odds ratio 15.7 [95% CI 2.6, 94.3]) and elevated UAE (27.3 [4.9, 149.9]) at 5 years of follow-up.

CONCLUSIONS

Compared with MBS, medical treatment of obese youth with T2D was associated with a higher odds of DKD over 5 years.

Change in gastrointestinal symptoms over the first 5 years after bariatric surgery in a multicenter cohort of adolescents

BACKGROUND

Roux-en-Y gastric bypass (RYGB) and vertical sleeve gastrectomy (VSG) are effective for weight loss in adolescents with severe obesity. However, little is known about adverse gastrointestinal symptoms (GIS) following these operations in adolescents. The objective was to examine GIS over 5 years after surgery and differences by surgery type.

METHODS

We prospectively studied 228 adolescents (161 RYGB, 67 VSG) undergoing bariatric surgery. Gastrointestinal symptoms were assessed before surgery, at 6-months, and yearly to 5 years after surgery. Symptom severity was dichotomized for analysis. Analysis of post-surgery symptoms involved linear models adjusting for baseline symptoms, BMI, early post-operative complication, sex, and race.

RESULTS

Participants at surgery were 17 ± 1.6 years with preoperative BMI 53 ± 9.4 kg/m². From 6 months to 5 years, gastroesophageal reflux symptoms (GERS), nausea, bloating, and diarrhea increased. Crude prevalence rates of GERS increased from 4% (1% RYGB, 11% VSG) at 6-months post-surgery to 14% (10% RYGB, 26% VSG) at 5-years. In adjusted analyses, the VSG group experienced 4-fold (4.85 95% CI 2.63, 8.91, p < 0.0001) greater odds of GERS compared to RYGB.

CONCLUSIONS

Adolescents who underwent VSG experienced greater risk of GERS compared to those undergoing RYGB. Adolescents undergoing VSG should be counseled preoperatively about GERS and objectively monitored postoperatively for gastroesophageal reflux when indicated.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, Identifier: NCT00474318, https://clinicaltrials.gov/ct2/show/NCT00474318?term=Teen-LABS&rank=1.

TYPE OF STUDY

Treatment Study.

LEVEL OF EVIDENCE

Level II.

Hypothalamic Obesity: 4 Years of the International Registry of Hypothalamic Obesity Disorders

OBJECTIVE

Hypothalamic obesity (HyOb) is a rare cause of rapid weight gain and early metabolic comorbidities. Effective treatment strategies are limited. The registry collected participant data and compared treatment approaches.

METHODS

The International Registry of Hypothalamic Obesity Disorders (IRHOD) was created as a registry portal to provide education. Data collected from the initial 4 years were evaluated.

RESULTS

Eighty-seven participants were included for analysis (median age: 27 years, range: 3-71 years). A total of 96.5% had obesity, and 3.5% had overweight at maximal weight. Seventy-five had brain tumors (86%)-the majority were craniopharyngiomas (72% of those with tumors). Nontumor etiologies included congenital brain malformation (4.6%), traumatic brain injury (3.4%), and genetic anomaly (2.3%). Ninety percent received obesity treatments including nutritional counseling (82%), pharmacotherapy (59%), bariatric surgery (8%), and vagal nerve stimulation (1%). Forty-six percent reported follow-up BMI results after obesity treatment. Surgery was most effective (median BMI decrease: -8.2 kg/m2 , median interval: 2.6 years), with lifestyle intervention (BMI: -3.4 kg/m2 , interval: 1.2 years) and pharmacological therapy (BMI: -2.3 kg/m2 , interval: 0.8 years) being less effective. Eighty percent of participants reporting follow-up weight remained in the obesity range.

CONCLUSIONS

IRHOD identified a large cohort with self-reported HyOb. Surgical therapy was most effective at weight reduction. Nutritional counseling and pharmacotherapy modestly improved BMI. Stepwise treatment strategy for HyOb (including nutritional, pharmacological, and surgical therapies in an experienced center) may be most valuable.

Roux-en-Y gastric bypass surgery in youth with severe obesity: 1-year longitudinal changes in spexin

BACKGROUND

Spexin is a novel peptide predominantly produced in human white adipose tissue and has recently been implicated as a potential signal in the regulation of body weight, energy homeostasis, and satiety. The effect of bariatric surgery on spexin is unknown.

OBJECTIVES

To study the effect of Roux-en-Y gastric bypass (RYGB) surgery on endogenous spexin concentration and various risk factors of type 2 diabetes and cardiovascular disease in youth with severe obesity.

SETTING

University hospital, United States METHODS: Spexin, body mass index (BMI), insulin, glucose, total and high molecular weight adiponectin, leptin, and high sensitivity C- reactive protein were measured longitudinally (baseline, 6 mo, and 12 mo) after RYGB surgery in girls with severe obesity (n = 12; age = 16.7 ± 1.5 years; BMI = 51.6 ± 2.9 kg/m²).

RESULTS

Serum spexin concentration increased (P = .01) at 6 months after surgery and stabilized afterward. Spexin level correlated negatively with homeostatic model assessment insulin resistance, HOMA-IR (Spearman correlation r = -.796, P < .001) and positively with high molecular weight adiponectin (Spearman correlation r = .691, P = .011). The change in spexin concentration, from baseline to 6 months after surgery, was inversely correlated with the corresponding change in BMI (Spearman correlation r = -.573, P = .051). Furthermore, the 6-month changes in spexin and HOMA-IR were inversely correlated (slope [standard error, SE] = -.0084 (.0019), P = .001)], even after adjusting for the change in BMI.

CONCLUSIONS

The enhancement of circulating spexin concentration in response to RYGB and correlations with beneficial postoperative changes in various adipokines in youth are novel findings that require further validation.

ASMBS pediatric metabolic and bariatric surgery guidelines, 2018

The American Society for Metabolic and Bariatric Surgery Pediatric Committee updated their evidence-based guidelines published in 2012, performing a comprehensive literature search (2009-2017) with 1387 articles and other supporting evidence through February 2018. The significant increase in data supporting the use of metabolic and bariatric surgery (MBS) in adolescents since 2012 strengthens these guidelines from prior reports. Obesity is recognized as a disease; treatment of severe obesity requires a life-long multidisciplinary approach with combinations of lifestyle changes, nutrition, medications, and MBS. We recommend using modern definitions of severe obesity in children with the Centers for Disease Control and Prevention age- and sex-matched growth charts defining class II obesity as 120% of the 95th percentile and class III obesity as 140% of the 95th percentile. Adolescents with class II obesity and a co-morbidity (listed in the guidelines), or with class III obesity should be considered for MBS. Adolescents with cognitive disabilities, a history of mental illness or eating disorders that are treated, immature bone growth, or low Tanner stage should not be denied treatment. MBS is safe and effective in adolescents; given the higher risk of adult obesity that develops in childhood, MBS should not be withheld from adolescents when severe co-morbidities, such as depressed health-related quality of life score, type 2 diabetes, obstructive sleep apnea, and nonalcoholic steatohepatitis exist. Early intervention can reduce the risk of persistent obesity as well as end organ damage from long standing co-morbidities.

Effect of bariatric surgery on urinary sphingolipids in adolescents with severe obesity

BACKGROUND

Untreated severe obesity of adolescents is associated with abnormal kidney function and development of chronic kidney disease. Lipotoxicity due to lipid accumulation in glomeruli might be an important mechanism in the progression of kidney disease in obesity.

OBJECTIVE

To assess subclinical glomerular injury by measuring urinary sphingolipids in adolescents with severe obesity before and after weight loss surgery. We hypothesized that the levels of urinary sphingolipids would be elevated at baseline and improve after weight reduction.

SETTING

Cincinnati Children's Hospital Medical Center, University of Cincinnati.

METHODS

Ten adolescents undergoing bariatric surgery with no microalbuminuria and normal kidney function were selected. Urinary sphingolipids (ceramides, glycosphingolipids, and sphingomyelins) were quantified using ultra performance liquid chromatography electrospray ionization tandem mass spectrometry at baseline and 1 year postoperatively. The levels of sphingolipids were compared with lean and moderately obese controls.

RESULTS

Participants with severe obesity had a mean baseline body mass index of 50 kg/m² that decreased to 36 kg/m² at 1 year postsurgery (28% reduction). Almost all urinary ceramides, glycosphingolipids, and sphingomyelin species were significantly elevated in participants with severe obesity compared with controls at baseline (P<.01). One year after weight loss surgery, levels of urinary sphingolipids improved but were still significantly elevated compared with controls.

CONCLUSIONS

Our study indicates that severe obesity is associated with increased urinary excretion of sphingolipids despite the absence of microalbuminuria or decreased kidney function. Urinary sphingolipids may therefore represent a marker of early (subclinical) glomerular injury in adolescents with severe obesity.

OSA screening with the pediatric sleep questionnaire for adolescents undergoing bariatric surgery in teen-LABS

OBJECTIVE

Obstructive sleep apnea (OSA) is reported in 70% of adolescents who present for bariatric surgery. The Pediatric Sleep Questionnaire (PSQ) was developed to identify children at risk for OSA but is not validated in adolescents with obesity. The aims of this study were: (1) to assess validity of the PSQ to detect OSA and (2) to determine the correlation between anthropometric and polysomnography measurements.

METHODS

A cross-sectional assessment of Teen-Longitudinal Assessment of Bariatric Surgery participants at high risk for OSA was performed. Participants completed an overnight polysomnography, and caregivers completed the PSQ.

RESULTS

Forty-five participants (84% female, 78% Caucasian, mean age = 16.7 ± 1.5 years) were evaluated. Mean BMI was 51.3 ± 7.7 kg/m² and mean obstructive apnea-hypopnea index (oAHI) was 6.1 ± 5.9 events/h. For diagnosis of OSA (oAHI ≥5), the total PSQ score sensitivity, specificity, and positive predictive value (PPV) were 86%, 38%, and 55%, respectively. For snoring >50% of the time, PPV was 84%, sensitivity was 64%, and specificity was 43%. Sagittal abdominal diameter correlated with oAHI and oxygen saturation nadir (ρ = 0.34, P = 0.027), whereas BMI, neck, and waist circumference correlated with neither.

CONCLUSIONS

The PSQ demonstrated low specificity, and PPV and the question regarding snoring >50% of the time did not effectively identify OSA. Sagittal abdominal diameter correlated with oAHI and oxygen saturation nadir.

Early improvement in obstructive sleep apnea and increase in orexin levels after bariatric surgery in adolescents and young adults

BACKGROUND

Obstructive sleep apnea (OSA) associated with obesity is known to improve after bariatric surgery, but little is known about early changes in this condition after surgery.

OBJECTIVES

To study the clinical course of OSA after bariatric surgery SETTING: Children's hospital in the United States METHODS: Adolescents and young adults with obstructive sleep apnea undergoing vertical sleeve gastrectomy (n = 6) or gastric bypass (n = 1) were enrolled in this prospective study. Participants underwent formal polysomnography before and at 3 and 5 weeks after bariatric surgery. Anthropometric measurements and assay for orexin and leptin were also performed at study visits. Thirty-one adolescents who underwent 2 polysomnography studies that were 4 weeks apart served as control patients.

RESULTS

Baseline mean (range) age of participants was 17.8 (15.4-20.7) years, 71% were male, with body mass index of 55.2 (41.3-61.6) kg/m² and had a median apnea hypopnea index (AHI) of 15.8 (7.1-23.8) events/hour. Differences in least-square means from longitudinal analysis did not show significant differences in AHI in the control group but showed significant postoperative decline in AHI relative to baseline. AHI declined postoperatively from baseline by 9.2 events/hour (95% confidence interval: 3.8 to 14.5) at 3 weeks (P = .002) and 9.1 events/hour (95% confidence interval: 3.8 to 14.5) at 5 weeks (P = .002); there was no significant change from 3 to 5 weeks in AHI. Leptin decreased and orexin levels increased significantly by 3 weeks postoperatively.

CONCLUSIONS

These observations suggest that OSA responds early and out of proportion to weight loss after metabolic and or bariatric surgery, thus weight independent factors may at least in part be responsible for early improvement in OSA postoperatively.

Abstract 195: Effects of Vertical Sleeve Gastrectomy on HDL Function in Adolescents with Severe Obesity

Severe obesity is a major problem among US adolescents and traditional weight loss strategies, including lifestyle intervention, have had limited efficacy. Bariatric surgery has grown in popularity because it results in rapid weight loss while improving cardiovascular disease risk factors, including raising high density lipoprotein cholesterol (HDL-C). Whether this rise in HDL-C translates into improved HDL cardioprotective function is not clear, particularly in adolescents. We studied the impact of weight loss surgery (vertical sleeve gastrectomy) in adolescents with severe obesity on HDL function pre and one year post operatively. Adolescents underwent laparoscopic vertical sleeve gastrectomy between in 2008-2011. HDL function (cholesterol efflux, HDL oxidation, and HDL inflammatory index) was measured pre and post-surgery on stored serum (-80°C) after apolipoprotein B depletion with polyethylene glycol. Only males were studied in this pilot study to minimize the known effects of sex and the menstrual cycle on lipoproteins. Changes pre and post-surgery were evaluated using paired t-tests. Participants (n=10, 90% Caucasian) were a mean±SD age of 17.4±1.6 years at baseline and 18.4 ±1.5 years at follow-up. After vertical sleeve gastrectomy, BMI was 32% lower than baseline (p<0.01). All lipid measurements improved and HDL-C increased by 23%. HDL function significantly improved post vertical sleeve gastrectomy compared to baseline, all p<0.01 (cholesterol efflux by 12%, HDL oxidation potential by 30%, and HDL inflammatory index by 25%). We conclude that vertical sleeve gastrectomy results in a significant improvement in HDL cholesterol levels and HDL function in adolescents with severe obesity. Whether these changes result in long term improvement in cardiovascular health remains to be determined.

Population pharmacokinetic-pharmacodynamic modeling and dosing simulation of propofol maintenance anesthesia in severely obese adolescents

BACKGROUND

Optimal dosing of propofol to maintain appropriate anesthetic depth is challenging in severely obese (SO) adolescents. We previously reported that total body weight (TBW) is predictive of propofol clearance. This study was aimed at characterizing pharmacokinetics (PK) and pharmacodynamics (PD) of propofol in SO adolescents, using bispectral index (BIS), and toward developing PK/PD model-based dosing guidelines.

METHODS

A prospective PK/PD study was conducted in 26 SO children and adolescents aged 9-18 years (body mass index 31-69 kg·m(-2)), undergoing surgery with intravenous propofol anesthesia clinically titrated by providers blinded to BIS. BIS data and propofol infusion schemes were recorded. Venous blood samples collected during and after propofol infusion were assayed for propofol concentrations. A propofol PK/PD model was developed using NONMEM and model-based simulations were performed to determine propofol dosing regimens targeting BIS of 50 ± 10.

RESULTS

A three-compartment PK model linked to a sigmoidal inhibitory Emax PD model by a first-order rate constant, adequately described the propofol concentration (n = 375) and BIS (n = 3334) data. TBW was the most predictive covariate for propofol clearance [CL (l·min(-1) ) = 1.65 × (TBW/70)(0.75)]. An effect-site propofol concentration of 3.19 μg·ml(-1) was estimated for half-maximal effect, with no identifiable predictive covariates. The proposed maintenance dosing regimen targeted to a BIS of 50 ± 10, based on our PK/PD model, was able to predict desired propofol concentrations and BIS in a representative obese teen when used in conjunction with accepted PK/PD models for children/obese adults (PK:Eleveld/PD: Cortinez), further supporting evidence for the dosing based on TBW.

CONCLUSION

This is the first study to describe the PK/PD of propofol in SO adolescents. The proposed maintenance dosing regimen for propofol uses TBW in an allometric function as a dosing scalar, with an exponent of 0.75. Our results suggest no relevant effect of obesity on the propofol concentration-BIS relationship.

Bariatric surgery in severely obese adolescents improves major comorbidities including hyperuricemia

OBJECTIVE

Serum uric acid (sUA) is believed to contribute to the pathogenesis of metabolic comorbidities like hypertension, insulin-resistance (IR) and endothelial dysfunction (EDF) in obese children. The present pilot study investigated the association between sUA concentrations and loss of body weight following laparoscopic sleeve gastrectomy (LSG) or laparoscopic Roux-en-Y-gastric bypass (RYGB) in severely obese adolescents.

MATERIALS/METHODS

10 severely obese adolescents underwent either LSG (n=5) or RYGB (n=5). 17 normal weight, healthy, age- and gender-matched adolescents served as a normal weight peer group (NWPG). Pre- and 12 months postoperatively, sUA and relevant metabolic parameters (glucose homeostasis, transaminases, lipids) were compared.

RESULTS

Preoperatively, sUA was significantly elevated in patients with severe obesity compared to NWPG. Twelve months after LSG and RYGB, a significant decrease in sUA, BMI, CVD risk factors, hepatic transaminases, and HOMA-IR was observed. Reduction in SDS-BMI significantly correlated with changes in sUA.

CONCLUSIONS

sUA levels and metabolic comorbidities improved following bariatric surgery in severely obese adolescents. The impact of changes in sUA on long-term clinical complications of childhood obesity deserves further study.

Bariatric surgery for severe obesity in two adolescents with type 1 diabetes

Bariatric surgery has been effective in treating type 2 diabetes mellitus (T2DM); it has not been used frequently in obese patients with type 1 diabetes mellitus (T1DM). This is the first case series reporting on the effect of bariatric surgery on diabetes control in adolescents with T1DM. Patient A is a 19-year-old obese man with T1DM who underwent vertical sleeve gastrectomy. At 12 months after surgery he demonstrated 28% reduction in BMI. His daily total insulin requirement had decreased; however, hemoglobin A1c remained primarily unchanged at 8.8%. Patient B is a 13-year-old obese girl with an initial clinical diagnosis of T2DM controlled on only metformin. She underwent Roux-en-Y gastric bypass; at 1 month after surgery she presented in diabetic ketoacidosis and was found to have positive islet cell antibodies, which were also present before surgery. Her diagnosis was revised to T1DM, and she was started on insulin. By 28 months after surgery her BMI had decreased by 42%. Since initiation of insulin, her daily total insulin requirement had decreased, but hemoglobin A1c had significantly worsened from 6.3% to 10%. We found that despite significant weight loss, improvements in cardiovascular risk factors (dyslipidemia and obstructive sleep apnea), and quality of life in our patients, bariatric surgery does not necessarily lead to improved glycemic control of T1DM. Patients with T1DM have ongoing dependency on exogenous insulin, and optimal glycemic control still depends on patient compliance with diabetes care.

An integrated population pharmacokinetic meta-analysis of propofol in morbidly obese and nonobese adults, adolescents, and children

This study describes a population pharmacokinetic meta-analysis of propofol to characterize the influence of body size measures and age in morbidly obese and nonobese adults, adolescents, and children. Sixty morbidly obese and nonobese adult patients (55-167 kg; 21-79 years) and 34 morbidly obese and nonobese adolescents and children (37-184 kg; 9-20 years) were included. The results show that clearance increased with total body weight in an allometric function while age was found to influence clearance in a bilinear fashion with two distinct slopes, reflecting an initial increase and subsequent decrease as a result of aging. Using these two functions, the influence of both (over)weight and age on propofol clearance was well characterized, which may provide a basis for dosing across this diverse group of patients.CPT: Pharmacometrics & Systems Pharmacology (2013) 2, e73; doi:10.1038/psp.2013.47; advance online publication 11 September 2013.

Clinical review: Bariatric surgery following treatment for craniopharyngioma: a systematic review and individual-level data meta-analysis

OBJECTIVES

Craniopharyngiomas are rare low-grade tumors located in the hypothalamic and/or pituitary region. Hypothalamic involvement and treatment resulting in hypothalamic damage are known to lead to development of "hypothalamic obesity" (HyOb) in 50% of cases. The management of HyOb, associated with eating disorders and rapid comorbidities, is an important issue. Bariatric surgery is the most effective therapy for weight loss in patients with severe exogenous obesity. The aim of this systematic review and meta-analysis was to determine the 12-month outcome of bariatric surgery for HyOb due to craniopharyngioma treatment.

METHODS AND RESULTS

Relevant studies were identified by searches of the MEDLINE and EMBASE databases until January 2013. A total of 21 cases were included: 6 with adjustable gastric banding, 8 with sleeve gastrectomy, 6 with Roux-en-Y gastric bypass, and 1 with biliopancreatic diversion. After data pooling, mean weight difference was -20.9 kg after 6 months (95% confidence interval [CI], -35.4, -6.3) and -15.1 kg after 12 months (95% CI, -31.7, +1.4). The maximal mean weight loss was achieved by the gastric bypass group: -31.0 kg (95% CI, -77.5, +15.5) and -33.7 kg (95% CI, -80.7, +13.3) after 6 and 12 months, respectively.

CONCLUSIONS

In this largest ever published study on the effect of bariatric surgery on obesity after craniopharyngioma treatment, we observed an important weight loss after 1 year of follow-up. Larger studies are warranted to establish appropriate selection criteria and the best surgical technique to perform bariatric surgery.

Evaluation of propofol anesthesia in morbidly obese children and adolescents

BACKGROUND

Poor characterization of propofol pharmacokinetics and pharmacodynamics in the morbidly obese (MO) pediatric population poses dosing challenges. This study was conducted to evaluate propofol total intravenous anesthesia (TIVA) in this population.

METHODS

After IRB approval, a prospective study was conducted in 20 MO children and adolescents undergoing laparoscopic surgery under clinically titrated propofol TIVA. Propofol doses/infusion rates, hemodynamic variables, times to induction and emergence, and postoperative occurrence of respiratory adverse events (RAE) were recorded, along with intraoperative blinded Bispectral Index/BIS and postoperative Ramsay sedation scores (RSS). Study subjects completed awareness questionnaires on postoperative days 1 and 3. Propofol concentrations were obtained at predetermined intra- and post-operative time points.

RESULTS

Study subjects ranged 9 - 18 years (age) and 97 - 99.9% (BMI for age percentiles). Average percentage variability of hemodynamic parameters from baseline was ≈ 20%. Patients had consistently below target BIS values (BIS < 40 for >90% of maintenance phase), delayed emergence (25.8 ± 22 minutes), increased somnolence (RSS ≥ 4) in the first 30 minutes of recovery from anesthesia and 30% incidence of postoperative RAE, the odds for which increased by 14% per unit increase in BMI (p ≤ 0.05). Mean propofol concentration was 6.2 mg/L during maintenance and 1.8 mg/L during emergence from anesthesia.

CONCLUSIONS

Our findings indicate clinical overestimation of propofol requirements and highlight the challenges of clinically titrated propofol TIVA in MO adolescents. In this setting, it may be advantageous to titrate propofol to targeted BIS levels until more accurate weight-appropriate dosing regimens are developed, to minimize relative overdosing and its consequences.

How young for bariatric surgery in children?

Obesity affects 50% of adults and 18% of children in the USA. It has wide-ranging comorbidities with clinical, psychosocial, and economic ramifications. Obesity refers to a condition of excess body fat. The basis for weight gain is a fundamental imbalance between caloric intake and output, but individual variation based on genetics, metabolism, and diverse environmental triggers is seen. Although modifications to our obesogenic society and education about the risks in our environment may lead to a decrease in the incidence of obesity through prevention, treatment for those already obese is critically important. In adults, the most successful treatment programs for obesity include a surgical procedure. This article discusses the problems obesity presents to children and their families, highlights the unique aspects of treating obesity in children, reviews the currently utilized bariatric surgical procedures, and introduces those bariatric procedures that are under development. When considering whether to use bariatric surgical procedures in a multidisciplinary weight management program for children, the special needs and characteristics of children with a severe weight problem must be considered. Development of bariatric surgical techniques and devices and implementation of these tools in multidisciplinary weight management programs need greater attention. This will require the combined efforts of the pediatric health care providers from many specialties and partnerships with industry to facilitate discovery and implementation.

Obesity identified by discharge ICD-9 codes underestimates the true prevalence of obesity in hospitalized children

OBJECTIVES

To define inpatient care of obese children with or without an obesity diagnosis.

STUDY DESIGN

A total of 29,352 inpatient discharges (18,459 unique inpatients) from a tertiary children's hospital were analyzed. Body mass index (BMI) was calculated from measured height and weight. "Obesity" was defined as BMI >or=95th percentile by using Centers for Disease Control and Prevention 2000 growth charts. "Diagnosed obesity" was defined by primary, secondary or tertiary International Classification of Diseases, Ninth Revision codes for "obesity" or "overweight." Analyses controlled for multiple inpatient records per individual.

RESULTS

A total of 5989 discharges from the hospital (20.4%) were associated with obesity, but only 512 discharges (1.7%) indicated obesity as a diagnosis. An obesity diagnosis identified only 5.5% of inpatient days for obese inpatients. Obese patients with an obesity diagnosis (Ob/Dx) had fewer hospital discharges per person and shorter lengths of stay than obese patients without an obesity diagnosis (Ob/No Dx). Patients with Ob/Dx had higher odds of mental health, endocrine, and musculoskeletal disorders than non-obese inpatients, but Ob/No Dx patients generally did not.

CONCLUSIONS

Inpatient obesity diagnoses underestimate inpatient utilization and misidentify patterns of care for obese children. Extreme caution is warranted when using obesity diagnoses to study healthcare utilization by obese children.