Effects of interrupting daily sedentary behavior on children's glucose metabolism: A 6-day randomized controlled trial.

BACKGROUND: Metabolic disease risk in youth is influenced by sedentary behaviors. Acute in-lab studies show that, during a single day, interrupting a sedentary period with short bouts of physical activity improves glucometabolic outcomes. OBJECTIVE: To determine if acutely improved glucose metabolism persists after multi-day interruptions of sitting with walking brief bouts. We hypothesized that children who underwent interrupting sitting on multiple days would demonstrate lower insulin area under the curve during an oral glucose tolerance test compared to uninterrupted sitting. METHODS: Healthy, normoglycemic children (N = 109) ages 7-11 years were randomized to one of two conditions: Control (3 h of daily Uninterrupted Sitting) or Interrupted Sitting (3-min of moderate-intensity walking every 30 min for 3 h daily); with dietary intake controlled through provision of foodstuffs for the entire experiment. Participants attended six consecutive daily visits at a research ambulatory unit. The primary outcome was insulin area under the curve during the oral glucose tolerance test on day 6 during interrupted or uninterrupted sitting; secondary outcomes included glucose and c-peptide area under the curve, energy intake at a buffet meal on day 6, and free-living activity. RESULTS: Among 93 children (42 uninterrupted sitting, 51 interrupted sitting), daily interrupted sitting resulted in 21% lower insulin (ß = 0.102 CI:0.032-0.172, p = 0.005) and a 10% lower C-peptide (ß = 0.043, CI:0.001-0.084, p = 0.045) area under the curve. Matsuda and Glucose Effectiveness Indices were also improved (p's < 0.05). There were no group differences in energy intake or expenditure. CONCLUSIONS: Sustained behavioral change by interrupting sedentary behaviors is a promising intervention strategy for improving metabolic risk in children.

Differentiating Childhood-Onset Schizophrenia From Other Childhood Disorders.

Childhood-onset schizophrenia (COS) is a rare disorder in which symptoms of schizophrenia occur before the age of 13 years. This disorder often has a complicated presentation that can mimic other childhood disorders including post-traumatic stress disorder (PTSD), autism spectrum disorder (ASD), major depressive disorder (MDD) with psychosis, and generalized anxiety disorder (GAD) among others. This is further complicated by the low prevalence rate of COS which limits understanding of the disorder. Accurate and timely diagnosis is crucial as failure to do so has adverse implications for long-term treatment outcomes and prognosis. In this study, a rare case of a 12-year-old girl with childhood-onset schizophrenia and key findings that help differentiate it from other childhood disorders are reviewed to guide diagnosis and treatment.

Estimating plasma glucose with the FreeStyle Libre Pro continuous glucose monitor during oral glucose tolerance tests in youth without diabetes.

Few studies have assessed the accuracy of the FreeStyle Libre Pro (FLP) continuous glucose monitor for estimating plasma glucose (PG) in non-diabetic children. OBJECTIVE: Determine the accuracy of FLP compared to PG during OGTT in healthy children. SUBJECTS: Children (7-11.99 years) with healthy weight and overweight/obesity (n = 33; 52% male). METHODS: Participants wore the FLP before and during a 2-hour OGTT; PG was measured at 30 minutes intervals. Potential systematic- and magnitude-related biases for FLP vs PG were examined. RESULTS: FLP 15-minute averages and PG were correlated at most timepoints during OGTT (r2 = 0.35-0.69, P's < .001 for time point 30-120 minutes) and for PG area under the curve (AUC) (r2 = 0.65, P < .0001). There were no systematic biases as assessed by Bland-Altman analyses for FLP AUC or for FLP at each OGTT timepoint. However, for fasting glucose, a significant magnitude bias was noted (r2 = 0.38, P < .001), such that lower PG was underestimated, and higher PG was overestimated by FLP readings; further, there was poor correlation between fasting PG and FLP (r2 = 0.06, P = .22). BMIz was also associated with FLP accuracy: FLP overestimated PG in children with low BMIz and underestimated PG in those with overweight/obesity for OGTT AUC and OGTT PG at baseline, 60, and 120 minutes (all P's ≤ .015). No adverse events occurred with FLP. CONCLUSIONS: Among children without diabetes, the FLP was well tolerated and correlated with post-OGTT glucose, but had magnitude bias affecting fasting glucose and appeared to underestimate plasma glucose in those with overweight/obesity. These results suggest potential limitations for the utility of the FLP for research.

Free Fatty Acids as an Indicator of the Nonfasted State in Children.

BACKGROUND: Ensuring children are fasting for blood draws is necessary to diagnose abnormalities in glucose homeostasis. We sought to determine if serum free fatty acid (FFA) concentrations might be a useful marker to differentiate the fed and fasted states among children. METHODS: A total of 442 inpatient (fasting) and 323 (postglucose load) oral glucose tolerance test samples of glucose, insulin, and FFA from children (age 5-18 years) who had healthy weight, overweight, or obesity were examined by receiver operating characteristic (ROC) curve analysis to identify a cut point for nonfasting. In a cross-sectional study, we compared mean FFA and percentage of FFA values below this cut point as a function of inpatient (n = 442) versus outpatient (n = 442) setting. RESULTS: The area under the curve of FFA was significantly better (P values < .001) than the area under the curve of glucose or insulin for identifying nonfasting. FFA <287 mEq/mL had 99.0% sensitivity and 98.0% specificity for nonfasting. Mean FFA was lower in outpatients than inpatients (P < .001); only 1.6% inpatient but 9.7% outpatient FFA values were consistent with nonfasting (P < .001). CONCLUSIONS: Clinicians cannot assume that pediatric patients are adequately fasted on arrival for fasting blood work. On the basis of having significantly lower outpatient than inpatient FFA values and more frequently suppressed FFA, children appeared less likely to be fasting at outpatient appointments. FFA value <287 mEq/mL was a sensitive and specific cutoff for nonfasting in children that may prove clinically useful.