In this direct replication of Mueller and Oppenheimer’s (2014) Study 1, participants watched a lecture while taking notes with a laptop ( n = 74) or longhand ( n = 68). After a brief distraction and without the opportunity to study, they took a quiz. As in the original study, laptop participants took notes containing more words spoken verbatim by the lecturer and more words overall than did longhand participants. However, laptop participants did not perform better than longhand participants on the quiz. Exploratory meta-analyses of eight similar studies echoed this pattern. In addition, in both the original study and our replication, higher word count was associated with better quiz performance, and higher verbatim overlap was associated with worse quiz performance, but the latter finding was not robust in our replication. Overall, results do not support the idea that longhand note taking improves immediate learning via better encoding of information.
Glucocorticoid metabolites are associated with body composition measures and are altered with weight status. Metabolic and bariatric surgery (MBS) results in significant changes in weight and body composition. However, MBS effects on glucocorticoid metabolites are unknown.
Abstract Female athletes with low energy availability are at risk for impaired bone microarchitecture and strength associated with hypogonadism. Data are lacking for bone outcomes in male athletes. We studied 31 men 16-30 years (n=15 runners with mean (±SD) mileage 43±4 miles/week, n=16 non-athlete controls). We assessed distal tibia and radius volumetric BMD (vBMD) and microarchitecture by high resolution peripheral quantitative CT (HRpQCT), estimated bone strength by microfinite element analysis and body composition by DXA. Testosterone, estradiol (by LC-MS) and leptin (by electrochemiluminescence) were measured. Groups did not differ for mean age (24.5±3.6y), BMI (22.2±2.6 kg/m2), lean mass, or testosterone or estradiol levels. Mean tibial cortical vBMD was lower and porosity higher in athletes than controls (p<0.01). In contrast, mean tibial trabecular vBMD and number were higher, and separation lower, in athletes (p<0.02). Athletes with BMI ≤ 21 kg/m2 had lower tibial failure load (bone strength estimate) than those with BMI >21 kg/m2 (p=0.007). Lean mass (R=0.85, p<0.0001), serum leptin (R=0.59, p=0.046) and estradiol (R=0.66, p=0.007), but not testosterone, were associated with tibial failure load in athletes. Athlete and control groups did not differ for HRpQCT variables at the radius. Despite weight-bearing activity, male runners have impaired tibial cortical BMD and microarchitecture, which may increase their risk for bone stress injuries. Lower leptin (reflecting lower fat mass) and estradiol (converted from testosterone in adipose tissue), as well as lean mass, are determinants of lower tibial strength in these athletes, suggesting that low energy availability is a risk factor for impaired bone strength in male runners. Presentation: Saturday, June 11, 2022 1:00 p.m. - 3:00 p.m., Sunday, June 12, 2022 12:36 p.m. - 12:41 p.m.
Adults with obesity have a reduction in branched-chain amino acid (BCAA) levels following metabolic and bariatric surgery (MBS), which is hypothesized to contribute to the metabolic advantages of MBS. We examined this relationship in 62 youth 13-24 years old with severe obesity (47 female) over 12 months. Thirty had sleeve gastrectomy (SG) and 32 were non-surgical controls (NS). We measured fasting insulin, glucose, glycated hemoglobin (HbA1c), isoleucine, leucine, and valine concentrations, and post-prandial insulin and glucose, following a mixed meal tolerance test. Twenty-four-hour food recalls were collected. At baseline, groups did not differ in the intake or the serum levels of BCAAs, HbA1C, HOMA-IR, Matsuda index, insulinogenic index, or oral Disposition index (oDI). Over 12 months, SG vs. NS had greater reductions in serum BCAAs, and SG had significant reductions in BCAA intake. SG vs. NS had greater reductions in HbA1c and HOMA-IR, with increases in the Matsuda index and oDI. In SG, baseline leucine and total BCAA concentrations were negatively correlated with the baseline Matsuda index. Reductions in serum leucine were positively associated with the reductions in HOMA-IR over 12 months. These associations suggest a potential role of BCAA in regulating metabolic health. Reducing dietary intake and serum BCAA concentrations may reduce insulin resistance.
Abstract Disclosure: I. Becetti: None. M. Lauze: None. H. Lee: None. M. Bredella: None. M. Misra: None. V. Singhal: None. Introduction: Branched-chain amino acids (BCAAs), isoleucine, leucine and valine, have been linked to obesity, insulin resistance (IR) and risk for type 2 diabetes. Adults with obesity have a reduction in BCAA levels following metabolic and bariatric surgery (MBS), which may contribute to the modulation of metabolic advantages of MBS. We examine for the first time this relationship in youth with moderate-to-severe obesity who underwent sleeve gastrectomy (SG). Objective: To examine changes in dietary intake and serum BCAAs in youth with obesity one-year after SG, and their associations with changes in markers of IR. Methods: 53 youth 13-25 years old with severe obesity (41 females) were followed for a year; 25 had SG and 28 were non-surgical controls (NS). Subjects had fasting glucose and insulin levels and a 24-hour food recall. We assessed baseline and 12-month change within (Wilcoxon signed-rank test) and between (Student’s t-test/Wilcoxon Rank Sum test) groups, and associations between BCAAs and markers of IR (Spearman’s correlation). Results: SG and NS groups were similar for age, sex and race. SG had higher median body mass index (BMI) vs. NS at baseline [45.3 (42.1, 53.7) vs. 41.9 (38.4, 47.1) kg/m2; p=0.02]. At baseline, SG and NS did not differ for intake or serum levels of isoleucine, leucine, valine or total BCAAs. SG and NS groups also did not differ at baseline for glycated hemoglobin (HbA1C) or Homeostatic Model Assessment for Insulin Resistance (HOMA-IR, marker of IR). Over a year, SG vs. NS had greater reductions in BMI, serum isoleucine, leucine, valine and BCAAs (p≤0.02), and SG had significant within group reductions in intake of isoleucine, leucine, valine and BCAAs (p≤0.048). Further, SG vs. NS groups had greater reductions in HbA1c and HOMA-IR (p≤0.007). Serum BCAA levels were not associated with their dietary intake. Baseline HOMA-IR was positively associated with baseline serum levels of leucine (ρ=0.56, p=0.01). Over one year, decreases in HOMA-IR and HbA1c were positively associated with decreases in serum valine (ρ=0.60 and ρ=0.63, p=0.01 and p=0.007, respectively). Associations between changes in HOMA-IR and serum valine held after controlling for BMI (baseline and change) and dietary intake of valine. Conclusion: We demonstrate decreases in BCAA intake and serum levels one-year post-SG in youth with obesity. Associations between BCAAs and IR markers, even after controlling for BMI, suggest a potential role of BCAA in regulating metabolic health. Reducing serum levels of BCAAs may reduce IR. Presentation: Friday, June 16, 2023
Abstract Objective Mechanisms underlying metabolic improvement following metabolic and bariatric surgery (MBS) may provide insight into novel therapies. Vasopressin improves body composition and protects against hypoglycemia. Associations of copeptin, a stable cleavage product of vasopressin, with BMI and insulin resistance suggest an adaptive increase in vasopressin to counteract metabolic disruption. To our knowledge, no study has investigated copeptin before and after MBS in humans. This study's aim was to investigate copeptin changes following MBS and associations with metabolic parameters. Methods This was a 12‐month longitudinal study of 64 youth (78% female; mean age 18.7 [SD 2.8] y) with obesity (mean BMI 45.6 [SD 6.8] kg/m 2 ) undergoing MBS ( n = 34) or nonsurgical (NS) lifestyle management ( n = 30). Fasting copeptin, hemoglobin A1c (HbA1c), homeostatic model assessment for insulin resistance (HOMA‐IR), body composition, and resting energy expenditure (REE) were assessed. Results Over 12 months, copeptin increased more (time‐by‐treatment p = 0.017) whereas HbA1c and adiposity decreased more after MBS than NS ( ps ≤ 0.036). Copeptin changes correlated negatively with percentage fat mass and REE changes (rho ≤ −0.29; p s ≤ 0.025) in the whole group, and they correlated positively with HbA1c and HOMA‐IR (rho ≥ 0.41; false discovery rate–adjusted p = 0.05) and negatively with REE changes (rho = −0.55; false discovery rate–adjusted p = 0.036) in the MBS group. Conclusions Increases in copeptin after weight loss in MBS compared with NS were associated with lower REE and higher HbA1c/HOMA‐IR values. Vasopressin may contribute to MBS‐related metabolic modifications.
Objective: Preclinical work suggests that excess glucocorticoids and reduced cortical γ-aminobutyric acid (GABA) may affect sex-dependent differences in brain regions implicated in stress regulation and depressive phenotypes. The authors sought to address a critical gap in knowledge, namely, how stress circuitry is functionally affected by glucocorticoids and GABA in current or remitted major depressive disorder (MDD). Methods: Multimodal imaging data were collected from 130 young adults (ages 18–25), of whom 44 had current MDD, 42 had remitted MDD, and 44 were healthy comparison subjects. GABA+ (γ-aminobutyric acid and macromolecules) was assessed using magnetic resonance spectroscopy, and task-related functional MRI data were collected under acute stress and analyzed using data-driven network modeling. Results: Across modalities, trait-related abnormalities emerged. Relative to healthy comparison subjects, both clinical groups were characterized by lower rostral anterior cingulate cortex (rACC) GABA+ and frontoparietal network amplitude but higher amplitude in salience and stress-related networks. For the remitted MDD group, differences from the healthy comparison group emerged in the context of elevated cortisol levels, whereas the MDD group had lower cortisol levels than the healthy comparison group. In the comparison group, frontoparietal and stress-related network connectivity was positively associated with cortisol level (highlighting putative top-down regulation of stress), but the opposite relationship emerged in the MDD and remitted MDD groups. Finally, rACC GABA+ was associated with stress-induced changes in connectivity between overlapping default mode and salience networks. Conclusions: Lifetime MDD was characterized by reduced rACC GABA+ as well as dysregulated cortisol-related interactions between top-down control (frontoparietal) and threat (task-related) networks. These findings warrant further investigation of the role of GABA in the vulnerability to and treatment of MDD.
Importance Individuals with anorexia nervosa maintain extremely low body weights despite elevations in the circulating orexigenic hormone ghrelin. Whether circulating levels of endogenous ghrelin are associated with weight gain in anorexia nervosa is unknown. Objective To examine the association between baseline ghrelin and future weight change in individuals with anorexia nervosa. Design, Setting, and Participants This prospective cohort study was conducted between April 1, 2014, and March 31, 2020, in the US. Girls and women aged 10 to 22 years were recruited from the greater Boston area from community and area treatment centers, enrolled, and followed up for 18 months. Statistical analyses were performed between January and August 2022. Exposures Presence or absence of anorexia nervosa and elevations in endogenous ghrelin. Main Outcomes and Measures Changes in age- and sex-standardized body mass index percentiles from baseline to 9- and 18-month follow-up were the main outcomes of interest. Results A total of 68 girls and young women (11 [16%] Asian, 4 [6%] Hispanic or Latina, 51 [75%] White [non–Hispanic or Latina], and 2 [3%] other race or ethnicity), including 35 with anorexia nervosa and 33 healthy controls of similar Tanner stage, were included in this study. Anorexia nervosa and healthy control groups were not statistically different by race and ethnicity, Tanner stage, number completing follow-up visits, and the duration between baseline and follow-up visits. At baseline, individuals with anorexia nervosa were slightly older (median [IQR], 20.1 [18.5-21.0] vs 18.7 [14.7-19.4] years; P = .005), had lower body mass index percentiles (median [IQR], 2.4 [0.3-4.7] vs 52.9 [40.4-68.3]; P &lt; .001), and had elevated circulating ghrelin area under the curve composite index (median [IQR], 1389.4 [1082.5-1646.4] vs 958.5 [743.0-1234.5] pg/mL; P = .003) compared with healthy individuals. In linear mixed-effects regression analyses, baseline ghrelin was associated with prospective weight gain after adjusting for diagnosis, age, race, and duration of follow-up (odds ratio, 2.35; 95% CI, 1.43-3.73; P = .004). Conclusions and Relevance In this cohort study, endogenous ghrelin was associated with longitudinal weight gain in individuals with anorexia nervosa. Further studies are warranted to confirm this result and examine its potential clinical utility in treatment development.
