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A frequent problem in longitudinal studies is that data may be assessed at subject-selected, irregularly spaced time-points, resulting in highly unbalanced outcome data, inducing bias, especially if availability of data is directly related to outcome. Our aim was to develop a multivariate joint model in a mixed outcomes framework to minimize irregular sampling bias. We demonstrate using blood glucose monitoring throughout pregnancy and risk of preterm birth among women with type 1 diabetes mellitus. Blood glucose measurements were unequally spaced and intensity of sampling varied between and within individuals over time. Multivariate linear mixed effects submodel for the longitudinal outcome (blood glucose), Poisson model for the intensity of glucose sampling, and logistic regression model for binary process (preterm birth) were specified. Association between models is captured through shared random effects. Markov chain Monte Carlo methods were used to fit the model. The multivariate joint model provided better prediction, compared with a joint model with a multivariate linear mixed effects submodel (ignoring intensity of glucose sampling) and a two-stage model. Most association parameters were significant in the preterm birth outcome model, signifying improvement of predictive ability of the binary endpoint by sharing random effects between glucose monitoring and preterm birth. A simulation study is presented to illustrate the effectiveness of the multivariate joint modeling approach.

In the context of competency-based medical education, poor student performance must be accurately documented to allow learners to improve and to protect the public. However, faculty may be reluctant to provide evaluations that could be perceived as negative, and clerkship directors report that some students pass who should have failed. Student perception of faculty may be considered in faculty promotion, teaching awards, and leadership positions. Therefore, faculty of lower academic rank may perceive themselves to be more vulnerable and, therefore, be less likely to document poor student performance. This study investigated faculty characteristics associated with low performance evaluations (LPEs).The authors analysed individual faculty evaluations of medical students who completed the third-year clerkships over 15 years using a generalised mixed regression model to assess the association of evaluator academic rank with likelihood of an LPE. Other available factors related to experience or academic vulnerability were incorporated including faculty age, race, ethnicity, and gender.The authors identified 50 120 evaluations by 585 faculty on 3447 students between January 2007 and April 2021. Faculty were more likely to give LPEs at the midpoint (4.9%), compared with the final (1.6%), evaluation (odds ratio [OR] = 4.004, 95% confidence interval [CI] [3.59, 4.53]; p 0.001). The likelihood of LPE decreased significantly during the 15-year study period (OR = 0.94 [0.90, 0.97]; p 0.01). Full professors were significantly more likely to give an LPE than assistant professors (OR = 1.62 [1.08, 2.43]; p = 0.02). Women were more likely to give LPEs than men (OR = 1.88 [1.37, 2.58]; p 0.01). Other faculty characteristics including race and experience were not associated with LPE.The number of LPEs decreased over time, and senior faculty were more likely to document poor medical student performance compared with assistant professors.

To establish the King-Devick test (KD) performance values for children and adolescents.Prospective cohort.Pediatric sports medicine clinics.Five hundred seven athletes presenting to a pediatric sports medicine clinic for non-concussion-related evaluations.Age, sex, and risk factors for abnormal concussion recovery.The King-Devick test time.Four hundred eighty-three participants were included in the final analysis, which included 60.5% girls (n = 292) and 39.5% boys (n = 191). The KD test performance varied by age with a steady decrease in test time yearly from 8 years through 14 years of age, where some plateauing occurred. Baseline scores changed approximately 31 seconds over ages 8 to 18. Analysis of variance results revealed a strong effect of age on overall mean KD time (P0.001). The KD test performance was not associated with sex or other studied concussion risk factors or comorbid conditions.The KD test performance was reported in a cohort of youth aged 8 to 18 years, allowing for comparison of performance in individuals who may not have a baseline assessment. If baseline testing is desired, at least yearly intervals seems to be appropriate through childhood and early adolescence.

Background Epstein-Barr Virus (EBV) is strongly associated with multiple sclerosis (MS). After initial infection, EBV maintains a life-long latent infection in B lymphocytes. Depletion of B lymphocytes from the blood with the anti-CD20 antibody ocrelizumab markedly reduces disease activity in MS. Our objective was to measure the effect of ocrelizumab treatment on the cellular immune response to EBV. Methods Blood was collected from MS patients before and during ocrelizumab treatment. Peripheral blood mononuclear cells were stimulated with various antigens, and the response was measured using tritiated thymidine for proliferation and ELIspot for number of interferon-γ producing cells. Results The proliferation to autologous EBV-infected cells (LCL) was decreased after both 6 and 12 months of treatment. The number of interferon-γ producing cells on ELIspot in response to stimulation with either LCL or EBV also decreased. Responses to varicella zoster virus, influenza virus, and a mitogen did not change significantly. Conclusion The cellular immune response to EBV and LCL decreases during treatment with ocrelizumab. The benefit of ocrelizumab for MS may be through removal of EBV antigenic stimulus.

Introduction: We sought to predict the course and rate of functional improvement and length of stay (LOS) in patients with ischemic and hemorrhagic strokes admitted to inpatient rehabilitation facilities(IRF). Aim: To study the course and associating factors affecting functional outcomes among a large cohort of stroke patients admitted to IRFs. Methods: The cohort consists of stroke patients admitted to 5 IRFs in Houston, between 4/17-8/19. Higher order polynomial (quartic, cubic, quadratic) regressions were fitted to predict the temporal relationship between FIM score improvement and LOS, and based on goodness of fit statistics, cubic polynomial fit was selected. Effects of interactions were tested and later dropped from the final model because of non-statistical significance. Models were adjusted for age, gender, stroke type (hemorrhagic vs ischemic), and stroke severity based on NIHSS. Results: The demographics of patients are presented in table 1. Among 679 patients, the univariate analyses reflected that age (F=24.2, p p p Conclusion: Patient’s age, ischemic vs hemorrhagic stroke were the most significant predictors when deriving the relationship between total FIM score and LOS while adjusting for stroke severity and patient’s gender, which plateaued after 2 weeks of IRF stay.

Background: Good collateral flow has been shown to have better outcomes after acute ischemic stroke (AIS), including for patients receiving IV thrombolysis (IVT) and mechanical thrombectomy (MT). Hypothesis: In patients with AIS who undergo MT, good collateral flow is associated with better functional independence measure (FIM) change. Design/Methods: Data was collected retrospectively for patients who presented with AIS and were treated with MT. A total of 54 patients from 4 inpatient rehabilitation facility (IRF) locations between April 2017 and August 2019 were included. Collateral score was collected from angiograms and CT angiogram (CTA) in cases where an angiogram was not available. FIM change was defined as the difference in FIM at admission to IRF and discharge from IRF. Regression analyses were conducted to estimate the relationship between collateral score and FIM change. The predictors in the model included collateral score, FIM at admission to IRF, age at onset, and gender. Logistic regression was used for categorical variables and linear regression was applied for continuous variables. Statistical significance level was set at 0.05. Collaterals were scored from 0 to 4, with 0 to 2 being poor and good collateral flow defined as scores 3 and 4. The primary outcome of this study was FIM change. Results: The mean age was 70.4 years, and 54.5% was female. Regression analyses did not show any significant differences in FIM change in patients with collaterals ranging from poor to good p = 0.807 (Table 1), when adjusted for age, gender, and severity as represented by FIM at admission to IRF. Conclusion: In this patient cohort, good collateral flow was not associated with improvement in FIM change.

Introduction: We asked whether intracerebral hemorrhage (ICH) patients admitted to inpatient rehabilitation facilities(IRF) improve differently based on their involvement of the corticospinal tract(CST). Aim: To predict associating radiological factors affecting discharge FIM score. Methods: We reviewed the patients’ characteristics and their respective imaging findings presenting with ICH between 4/17 to 8/19. The ICH volume and edema around the ICH were measured using analyze software. The main outcome measure was FIM score at time of discharge. Statistical significance was set at 0.05. Results: Among the 53 patients included, 49% were female. The median age of the patients was 62 years (IQR 25,89). The median length of stay at IRF was 22days (IQR 14,26). In univariate analysis, FIM score at the time of discharge FIM score at the time of discharge admission were significantly associated with NIHSS (estimate -1.26, pp = 0.008), gender ( p p p =0.02). Conclusion: This preliminary study suggests that functional improvement declines in ICH patients with CST involvement.

Exposure to maternal diabetes in utero increases the risk in the offspring for a range of metabolic disturbances. However, the timing and variability of in utero hyperglycemic exposure necessary to cause impairment have not been elucidated. The TEAM Study was initiated to evaluate young adult offspring of mothers with pregestational diabetes mellitus. This paper outlines the unique enrollment challenges of the TEAM Study and preliminary analysis of the association between exposure to diabetes in pregnancy and adverse metabolic outcomes. The TEAM Study enrolls offspring of women who participated in a Diabetes in Pregnancy (DiP) Program Project Grant between 1978 and 1995. The DiP Study collected medical and obstetric data across pregnancy. The first 96 eligible offspring of women with pregestational diabetes were age-, sex-, and race-matched to adults from the National Health and Nutrition Examination Survey (NHANES) 2015-2016 with an OGTT. Descriptive and regression analyses were employed to compare TEAM participants to NHANES participants. Among a subset of TEAM participants, we compared the metabolic outcomes across maternal glucose profiles using a longitudinal data clustering technique that characterizes level and variability, in maternal glucose across pregnancy. By comparing categories of BMI, TEAM Study participants had over 2.0 times the odds of being obese compared to matched NHANES participants (for class III obesity, OR = 2.81 ; 95% confidence interval (CI): 1.15, 6.87). Increasing levels of two-hour glucose were also associated with in utero exposure to pregestational diabetes in matched analyses. Exposure to pregestational diabetes in utero may be associated with an increased risk of metabolic impairment in the offspring with clinical implications.

This prospective cohort analysis describes changes in weight, cardiometabolic health, and weight-related quality of life (WRQOL) following adolescent LAGB. Teen-Longitudinal Assessment of Bariatric Surgery (Teen-LABS) collected demographic, anthropometric, micronutrient, cardiometabolic risk, and WRQOL data for 242 adolescents. Data through 5 years were analyzed for 14 participants who underwent LAGB with 2 patients lost to follow-up. Participants (mean age 18.2 ± 0.4 years) were mostly female (86%) and white (71%) with a median body mass index (BMI) of 48.7 kg/m2 (45.5–54.1). Preoperatively, 100%(13/13), 62%(8/13), 57%(8/14), and 7%(1/14) had elevated high sensitivity C-reactive protein (hs-CRP), dyslipidemia, elevated blood pressure (EBP), and type 2 diabetes (T2D), respectively. At 5 years, mean BMI decreased by 3.3% (51.0 vs. 49.3 kg/m2, p = 0.6), 43%(6/14) had BMI values exceeding baseline and 21% (3/14) underwent band removal. Postoperative prevalence of hs-CRP, dyslipidemia, EBP, and T2D was 45% (4/11), 36% (5/11), 33% (4/12), and 0% (0/11), respectively. Adolescents undergoing LAGB experienced modest initial weight loss and improvements in cardiovascular risk factors with later weight regain and frequent need for band removal. Despite the small sample size, this prospective study highlights long-term outcomes with high rates of participant retention over time. Clinical Trial Registration: NCT00465829

Background. Characterizing maternal glucose sampling over the course of the entire pregnancy is an important step toward improvement in prediction of adverse birth outcome, such as preterm birth, for women with type 1 diabetes mellitus (T1DM). Objectives. To characterize the relationship between the gestational glycemic profile and risk of preterm birth using a joint modeling approach. Methods. A joint model was developed to simultaneously characterize the relationship between a longitudinal outcome (daily blood glucose sampling) and an event process (preterm birth). A linear mixed effects model using natural cubic splines was fitted to predict the longitudinal submodel. Covariates included mother’s age at last menstrual period, age at diabetes onset, body mass index, hypertension, retinopathy, and nephropathy. Various association structures (value, value plus slope, and area under the curve) were examined before selecting the final joint model. We compared the joint modeling approach to the time-dependent Cox model (TDCM). Results. A total of 16,480 glucose readings over gestation (range: 50-260 days) with 32 women (28%) having preterm birth was included in the study. Mother’s age at last menstrual period and age at diabetes onset were statistically significant (beta = 1.29, 95% CI 1.10, 1.72; beta = 0.84, 95% CI 0.62, 0.98) for the longitudinal submodel, reflecting that older women tended to have higher mean blood glucose and those with later diabetes onset tended to have a lower mean blood glucose level. The presence of nephropathy was statistically significant in the event submodel (beta = 2.29, 95% CI 1.05, 4.48). Cumulative association parameterization provided the best joint model fit. The joint model provided better fit compared to the time-dependent Cox model (DIC JM=19,895; DIC TDCM=19,932). Conclusion. The joint model approach was able to simultaneously characterize the glycemic profile and assess the risk of preterm birth and provided additional insights and a better model fit compared to the time-dependent Cox model.

OBJECTIVES: To evaluate the longitudinal effects of metabolic and bariatric surgery (MBS) on the prevalence of musculoskeletal and lower extremity (LE) pain, physical function, and health-related quality of life. METHODS: The Teen Longitudinal Assessment of Bariatric Surgery study (NCT00474318) prospectively collected data on 242 adolescents undergoing MBS at 5 centers over a 3-year follow-up. Joint pain and physical function outcomes were assessed by using the Health Assessment Questionnaire Disability Index, Impact of Weight on Quality of Life – Kids, and the Short Form 36 Health Survey. Adolescents with Blount disease (n = 9) were excluded. RESULTS: Prevalent musculoskeletal and LE pain were reduced by 40% within 12 months and persisted over 3 years. Adjusted models revealed a 6% lower odds of having musculoskeletal pain (odds ratio = 0.94, 95% confidence interval: 0.92–0.99) and a 10% lower odds of having LE pain (odds ratio = 0.90, 95% confidence interval: 0.86–0.95) per 10% reduction of BMI. The prevalence of poor physical function (Health Assessment Questionnaire Disability Index score >0) declined from 49% to CONCLUSIONS: Joint pain, impaired physical function, and impaired health-related quality of life significantly improve after MBS. These benefits in patient-reported outcomes support the use of MBS in adolescents with severe obesity and musculoskeletal pain and suggest that MBS in adolescence may reverse and reduce multiple risk factors for future joint disease.

OBJECTIVE: To examine the influence of age, sex, attention-deficit hyperactivity disorder (ADHD) status, previous history of concussion, and days since injury on postconcussion postural control assessment in adolescents who have suffered a concussion. DESIGN: Prospective cohort study. SETTING: Hospital-based outpatient clinic. PARTICIPANTS: Seventy-one participants (42 males; 29 females) with mean age 14.14 ± 2.44. INDEPENDENT VARIABLES: Age, sex, previous concussion history, ADHD status, total and severity of postconcussion symptoms, and days since injury. MAIN OUTCOME MEASURES: Total Balance Error Scoring System score, path length, center-of-pressure (COP) area, sample entropy, and Romberg quotient. RESULTS: Pearson product-moment correlation coefficients were calculated to test for potential associations between the continuous participant characteristics and the postural control variables. Spearman correlation was used to test the association between symptom severity and the postural control variables. Standard multiple regression was used to model the extent to which participant characteristics accounted for the variance in the postural sway variables. Age was significantly associated with all of the postural sway variables except COP area for the eyes open condition and sample entropy in the anterior-posterior direction for the eyes closed condition. Sex, ADHD status, and previous concussion history did not significantly predict postural control scores. CONCLUSIONS: Age significantly influences scores on common postconcussion postural control assessments. CLINICAL RELEVANCE: This study demonstrates that age is a critical factor that needs to be accounted for to improve the clinical appropriateness and utility of current postconcussion postural control assessments. Language: en

Women with pre-gestational diabetes have a high rate of large for gestational age (LGA) babies compared to women without diabetes. In particular, there is a high rate of asymmetric LGA defined as ponderal index (PI) &gt, 90th percentile for gestational age. We examined the association of birth weight and PI, with body mass index (BMI) and obesity status in adulthood, in a cohort of offspring of women with pre-gestational diabetes. The women participated in the Diabetes in Pregnancy (DiP) study at the University of Cincinnati from 1978 to 1995. The offspring of these women are the cohort participating in an observational study being conducted at Cincinnati Children&rsquo, s Hospital Medical Center. Once located, the offspring were invited to come in for a one-day clinic visit to assess anthropometrics, and their metabolic, renal and cardiovascular status. Linear and logistic regression was used to assess the association between birth weight and PI with current BMI. We report on 107 offspring. A statistically significant association was found between offspring current BMI with birth PI (&beta, = 1.89, 95%CI 0.40&ndash, 3.38), and between offspring current obesity status and birth asymmetric LGA (aOR = 2.44, 95%CI 1.01&ndash, 5.82). This is consistent with in utero &ldquo, metabolic programming&rdquo

Teen-LABS is a multicenter, prospective observational study of adolescents undergoing bariatric surgery. Predictors of resolution of NAFLD post-surgery are unclear. We evaluated changes in serum ALT levels, an acceptable surrogate when liver biopsy is not feasible, in 219 Teen-LABS subjects 3 years post gastric bypass or vertical sleeve gastrectomy. Three years post-surgery, median BMI declined to 38.4 from 52.6 kg/m2 at baseline (p In conclusion, while weight loss was associated with decreased ALT by 6 months post-surgery, improved fasting glycemia, insulin resistance and dyslipidemia indices were also independently associated with ALT decline. Association between change in predictor variables and decline in ALT from baseline to 6 months.Change in predictor variables over 6 monthsEstimate (SE) adjusted for age, race, sexp-valueEstimate (SE) adjusted for age, race, sex, change in BMIp-valueDecline in BMI0.64 (0.13) Disclosure F. Bacha: Research Support; Self; AstraZeneca, JAEB Center For Health Research, National Institutes of Health, Pediatric Diabetes Consortium. R. Gupta: None. T.M. Jenkins: None. M. Brandt: None. T.H. Inge: Consultant; Self; Standard Bariatrics, Independent Medical Expert Consulting Services, UpToDate. D. Kleiner: None. S. Xanthakos: None.

This study aimed to provide insight into the development of postural control abilities in youth. A total of 276 typically developing adolescents (155 males, 121 females) with a mean age of 13.23 years (range of 7.11–18.80) were recruited for participation. Subjects performed two-minute quiet standing trials in bipedal stance on a force plate. Center of pressure (COP) trajectories were quantified using Sample Entropy (SampEn) in the anterior-posterior direction (SampEn-AP), SampEn in the medial–lateral direction (SampEn-ML), and Path Length (PL) measures. Three separate linear regression analyses were conducted to predict the relationship between age and each of the response variables after adjusting for individuals’ physical characteristics. Linear regression models showed an inverse relationship between age and entropy measures after adjusting for body mass index. Results indicated that chronological age was predictive of entropy and path length patterns. Specifically, older adolescents exhibited center of pressure displacement (smaller path length) and less complex, more regular center of pressure displacement patterns (lower SampEn-AP and SampEn-ML values) compared to the younger children. These findings support prior studies suggesting that developmental changes in postural control abilities may continue throughout adolescence and into adulthood.

Sleep-related infant deaths have plateaued in the past decade, disproportionately affecting low socioeconomic status (SES) families. Printed materials are widely used for anticipatory guidance, yet none for safe sleep has been studied. We tested the efficacy of a specially designed children's book compared to brochures for safe sleep knowledge and adherence, which we hypothesized would be greater due to superior readability and engagement.This randomized controlled trial involved low-SES mothers (n = 282) enrolled in a home visiting program. Home visitors (n = 56) were randomly assigned to perform safe sleep teaching and assessments during 3 visits: third trimester, 1 week old, and 2 months old, exclusively utilizing a specially designed children's book or brochures, and surveys incorporating the American Academy of Pediatrics' safe sleep recommendations. Outcomes were safe sleep knowledge, adherence, and usefulness of materials, controlling for maternal health literacy.Safe sleep knowledge increased across all time points with no overall group difference, though gains for sleep-evocative and general health items varied. Odds of bed sharing were higher and exclusive crib use lower for the brochure group (P .05). Mothers and home visitors reported similar usefulness, though home visitors reported greater dialogue via the book and mothers in the book group reported more book sharing with their baby.While a specially designed children's book and brochures were equally effective conveying aggregate safe sleep knowledge in low-SES mothers, adherence to exclusive crib use and avoiding bed sharing were greater in the book group, attributable to enhanced dialogue, readability and emotional engagement. Children's books are a promising mode of anticipatory guidance, warranting further investigation.

The aim of this study is to determine the contribution of strain ε cc in mid left ventricular (LV) segments to the reduction of composite LV circumferential ε cc in assess severity of duchenne muscular dystrophy (DMD) heart disease as assessed by cardiac magnetic resonance imaging (CMR). DMD patients and control subjects were stratified by age, LV ejection fraction, and late gadolinium enhancement (LGE) status. Tagged CMR images were analyzed for global ventricular function, LGE imaging, and composite and segmental ε cc. The relationship between changes in segmental ε cc changes and LGE across patient groups was assessed by a statistical step-down model. LV ε cc exhibited segmental heterogeneity; in control subjects and young DMD patients, ε cc was greatest in LV lateral free wall segments. However, with increasing age and cardiac disease severity as demonstrated by decreased EF and development of myocardial strain the segmental differences diminished. In subjects with advanced heart disease as evidenced by reduced LV ejection fraction and presence of LGE, very little segmental heterogeneity was present. In control subjects and young DMD patients, ε cc was greatest in LV lateral free wall segments. Increased DMD heart disease severity was associated with reduced composite; ε cc diminished regional ε cc heterogeneity and positive LGE imaging. Taken together, these findings suggest that perturbation of segmental, heterogeneous ε cc is an early biomarker of disease severity in this cross-section of DMD patients.

Aim.To examine the gestational glycemic profile and identify specific times during pregnancy that variability in glucose levels, measured by change in velocity and acceleration/deceleration of blood glucose fluctuations, is associated with delivery of a large-for-gestational-age (LGA) baby, in women with type 1 diabetes.Methods.Retrospective analysis of capillary blood glucose levels measured multiple times daily throughout gestation in women with type 1 diabetes was performed using semiparametric mixed models.Results.Velocity and acceleration/deceleration in glucose levels varied across gestation regardless of delivery outcome. Compared to women delivering LGA babies, those delivering babies appropriate for gestational age exhibited significantly smaller rates of change and less variation in glucose levels between 180 days of gestation and birth.Conclusions.Use of innovative statistical methods enabled detection of gestational intervals in which blood glucose fluctuation parameters might influence the likelihood of delivering LGA baby in mothers with type 1 diabetes. Understanding dynamics and being able to visualize gestational changes in blood glucose are a potentially useful tool to assist care providers in determining the optimal timing to initiate continuous glucose monitoring.

Objective The normal diameter of the extrahepatic bile duct (EHD) in children has been poorly studied. Prior studies have enrolled small subject numbers, have studied only specific pediatric age groups, or have potential bias due to loosely defined exclusion criteria. We sought to establish parameters for the normal diameter of the EHD in children from birth to late adolescence, including premature infants. Methods A 12½-month institutional review board-approved, Health Insurance Portability and Accountability Act-compliant, retrospective chart review of all transabdominal ultrasounds performed on children (younger than 18 years) was conducted at a single pediatric tertiary referral center. Exclusion criteria included a past medical history of any pancreaticobiliary or hepatology disorder. New abnormal findings related to the liver, biliary system, or pancreas were also excluded. Recorded EHD measurements from review of the radiology reports were compiled. Estimated mean and 95% prediction intervals of EHD were calculated and reported for 6 nonoverlapping pediatric age groups. Results A total of 1016 ultrasounds on unique patients were included within the study. Estimated mean values and calculated 95% prediction intervals (in parentheses) for the diameter of the EHD were prematurity, 0.7 (0.3-1.7) mm; 0 to 2 months, 1.0 (0.4-2.3) mm; 3 to 11 months, 1.2 (0.5-2.9) mm; 1 to 4 years, 1.4 (0.6-3.3) mm; 5 to 12 years, 1.9 (0.8-4.3) mm; 13 to 17 years, 2.3 (1.0-5.2) mm. Conclusions Our derived data of normal predicted parameters of the EHD diameter in children of all age groups will help guide clinicians in identifying those patients outside the norm that may benefit from additional testing.

Background Cardiomyopathy is a heterogeneous disease with a strong genetic component. A research-based pediatric cardiomyopathy registry identified familial, syndromic, or metabolic causes in 30% of children. However, these results predated clinical genetic testing. Methods and Results We determined the prevalence of familial, syndromic, or metabolic causes in 83 consecutive unrelated patients referred for genetic evaluation of cardiomyopathy from 2006 to 2009. Seventy-six percent of probands (n = 63) were categorized as familial, syndromic, or metabolic. Forty-three percent (n = 18) of hypertrophic cardiomyopathy (HCM) patients had mutations in sarcomeric genes, with MYH7 and MYBPC3 mutations predominating. Syndromic (17%; n = 7) and metabolic (26%; n = 11) causes were frequently identified in HCM patients. The metabolic subgroup was differentiated by decreased endocardial shortening fraction on echocardiography. Dilated cardiomyopathy (DCM) patients had similar rates of syndromic (20%; n = 5) and metabolic (16%; n = 4) causes, but fewer familial cases (24%; n = 6) compared with HCM patients. Conclusions The cause of cardiomyopathy is identifiable in a majority of affected children. An underlying metabolic or syndromic cause is identified in >35% of children with HCM or DCM. Identification of etiology is important for management, family-based risk assessment, and screening.

Infants and children with repaired congenital diaphragmatic hernia (CDH) often continue to show delayed growth and development that may be, in part, secondary to unrecognized persistence of increased pulmonary vascular resistance (PVR). Data were reviewed from all patients ages 6–36 mo with repaired CDH who underwent cardiac catheterization from 2007 to 2010 and were compared to data from a control population of patients undergoing percutaneous closure of a patent ductus arteriosus (PDA). Indexed pulmonary blood flow (Qp), mean pulmonary artery pressure (mPAP), pulmonary capillary wedge pressure (PCWP), and PVR were examined. Data from 8 CDH patients and 10 control patients were examined. The mPAP (22.5 ± 3.33 vs. 18.2 ± 4.13 mm Hg) and PVR (3.66 ± 0.79 vs. 1.22 ± 0.4 iwU (indexed Wood’s units)) were both significantly elevated in the CDH population, whereas the Qp (4.08 ± 1.43 vs. 6.82 ± 1.46 l/min/m2) was significantly lower in this population. There was no significant difference in pulmonary capillary wedge pressure (PCWP). Less than half of the CDH patients had signs of pulmonary hypertension (PH) on echocardiogram. Our data suggest that children who are ages 6–36 mo with repaired CDH have significantly increased PVR compared with controls and early consideration of cardiac catheterization may be warranted.

ObjectivesThis study describes results of tracheal reconstruction in children with slide tracheoplasty with cardiopulmonary bypass and identifies predictors for adverse outcomes.MethodsPreoperative characteristics, operative variables, and outcome measures were collected for children undergoing slide tracheoplasty with cardiopulmonary bypass between April 2001 and October 2009. Predictors of worse outcomes were identified by bivariate analysis. Multiple regression analysis was performed for predictors of prolonged hospital stay.ResultsCohort included 80 patients (median age, 8.7 months; 7 days–21 years). Forty-eight patients had associated cardiac or great vessel anomalies; 24 had simultaneous repair of cardiovascular anomaly at tracheal reconstruction. Fifty (63%) were extubated within 48 hours after operation. Median stay was 18.5 days (range, 7–119 days). Twenty-three patients (29%) required significant airway reintervention during median follow-up of 12 months (range, 4 months–7.8 years). There were 4 deaths, 2 early and 2 late. In bivariate analysis, age (P = .017), cardiopulmonary bypass duration (P = .025), and duration of mechanical ventilation (P

Background To make informed decisions in dosing erythropoiesis-stimulating agents and intravenous iron therapy, clinicians must determine whether differences between current and previous test results for anemia and iron status markers reflect expected variation, a significant change, or an actual trend. Study Design Prospective observational cohort study. Setting & Participants 30 patients undergoing thrice-weekly in-center hemodialysis. Predictor Within-patient biological variations in hemoglobin (Hb) level, hematocrit (Hct), reticulocyte Hb content, transferrin saturation (TSAT), and ferritin level were determined over 12 consecutive treatment days. Outcomes & Measurements We separately measured same-sample analytical variation and within-patient biological variation (coefficient of variation), then calculated the number of sampling days needed to determine the true or homeostatic value for each analyte with 95% probability. We also evaluated whether results differed among the first, second, and third dialysis days of the week. Results Biological variation differed by analyte. Hb level (4.0%), Hct (4.0%), and reticulocyte Hb content (4.8%) showed much lower variation than TSAT (38.2%) or ferritin level (15.1%). Analytical variation ranged from 2.0%-6.9% for all analytes. We found that one sample day would be sufficient to establish the true mean Hb level or Hct within a level of closeness ±20% and 95% probability. For the same levels of closeness and probability, one sample day would be needed for reticulocyte Hb content, 15 for TSAT, and 3 for ferritin level. No pairwise comparison for any of the 5 analytes yielded a significant difference between results obtained on the first, second, or third dialysis day of the week. Limitations These findings may not apply to other patient populations. Conclusions Low biological variation renders Hb level, Hct, and reticulocyte Hb content, but not TSAT and ferritin level, suitable for trend analysis using results from 2 successive samples. TSAT and ferritin test results, unlike reticulocyte Hb content, have limited value in evaluating changes in iron status within individual hemodialysis patients.

The second edition of Methods in Medical Ethics, edited by Jeremy Sugarman and Daniel P. Sulmasy, is remarkably well written and serves as a comprehensive overview of research methods in the field ...

Purpose Highly skewed count data with excess zeros challenge the application of conventional statistical methods. Additional problems arise from repeated zero-inflated measures. Longitudinal zero-inflated Poisson (ZIP-mixed) models are mixtures of logistic and Poisson models that accommodate excess zeros and repeated counts. We compared a ZIP-mixed model with traditional Poisson and negative binomial models using data on problems with female condom use reported by women at high risk of sexually transmitted diseases. Methods The follow-up experience of this cohort represents a mixture of “perfect use” (no opportunity to report problems), represented by the structural zeros, and use experience that bears the risk of condom use problems, represented by a Poisson distribution. Results The ZIP-mixed model provided better fit and richer results than other models. The odds of being in the zero problem category increased with age (odds ratio [OR] = 1.1 per additional year, 95% confidence interval [CI]: 1.0–1.3) and with follow-up (OR = 3.0 per additional month, 95% CI: 1.4–6.0).The nonzero problem rate was lower among women who believed in the benefits of condom use (rate ratio [RR] = 0.9, 95% CI: 0.7–1.0) and had no sexually transmitted diseases at baseline (RR = 0.7, 95% CI: 0.6–0.9), and it decreased during follow-up (RR = 0.8 per additional month, 95% CI: 0.7–0.9). Conclusions Using ZIP-mixed model provided further insights into the determinants of condom failure.

The purpose of this investigation was to estimate and document the reliability and validity of the Anterior Knee Pain Scale (AKPS) and to estimate its relative prediction accuracy of anterior knee pain in young females.Data from a prospective, epidemiologic study to diagnose patellofemoral knee pain among female athletes (n = 499) using the Anterior Knee Pain Scale (AKPS). Data were treated in 4 phases (descriptive phase, reliability phase, scale refinement phase) and a final validation stage that was focused on an effort to test and document the validation of the AKPS short form and perform head-to-head comparisons of the 6-item short form with the original, 13-item form.The AKPS was reduced from 13 items (αCoeff = 0.77, σSEM = 0.004) to 6 items (αCoeff = 0.78, σSEM = 0.004). Point-biserial correlations with patellofemoral pain diagnosis were comparable: r [498] = 0.70 (R(2) = 0.49, short form) and r [498] = 0.71 (R(2) = 0.51, long form), as was sensitivity: 84% (short form) and 80% (long form), and specificity: 89% (short form) and 90% (long form; AUC = 0.94 both).The current analyses indicate that a subset of measures from the AKPS is responsive to patellofemoral pain symptoms and may support screening for related diagnoses. A simpler and quicker scale optimized for diagnostic accuracy could reduce the demand on patients, clinicians and research teams focused on the identification and management of patellofemoral pain.III.

The short version of the Disabilities of the Arm, Shoulder and Hand instrument (QuickDASH) has been shown to be a valid, reliable, and responsive measure of upper extremity function in adults. However, the psychometric properties of the QuickDASH for younger patients have not been well established. The purpose of this study was to evaluate the internal consistency and validity of the QuickDASH for use with older children and adolescents.The QuickDASH and PedsQL instruments were administered to 149 patients grouped into ages 8 to 12 and 13 to 18 years.Item response analysis showed a low SE of measurement (0.06) and a high coefficient α (0.91), suggesting high internal consistency among items. The QuickDASH was found to be a predictor of PedsQL score for both groups (P0.01).The results indicate that the QuickDASH is a consistent and valid instrument for older children and adolescents with upper extremity pathology.III, case series.

Discrete, highly skewed distributions with excess numbers of zeros often result in biased estimatesand misleading inferences if the zeros are not properly addressed. A clinical example of children withelectrophysiologic disorders in which many of the children are treated without surgery is provided. Thepurpose of the current study was to identify the optimal modeling strategy for highly skewed, zeroinflateddata often observed in the clinical setting by: (a) simulating skewed, zero-inflated count data;(b) fitting simulated data with Poisson, Negative Binomial, Zero-Inflated Poisson (ZIP) and Zero-inflatedNegative Binomial (ZINB) models; and, (c) applying the aforementioned models to actual, highlyskewed, clinical data of children with an EP disorder. The ZIP model was observed to be the optimalmodel based on traditional fit statistics as well as estimates of bias, mean-squared error, and coverage. &nbsp

Importance Severe obesity is associated with mobility limitations and higher incidence of multijoint musculoskeletal pain. It is unknown whether substantial weight loss improves these important outcomes in adolescents with severe obesity. Objective To examine the association of bariatric surgery with functional mobility and musculoskeletal pain in adolescents with severe obesity up to 2 years after surgery. Design, Setting, and Participants The Teen – Longitudinal Assessment of Bariatric Surgery Study is a prospective, multicenter, observational study, which enrolled 242 adolescents (≤19 years of age) who were undergoing bariatric surgery from March 2007 through February 2012 at 5 US adolescent bariatric surgery centers. This analysis was conducted in November 2015. Interventions Roux-en-Y gastric bypass (n = 161), sleeve gastrectomy (n = 67), or laparoscopic adjustable gastric band (n = 14). Main Outcomes and Measures Participants completed a 400-m walk test prior to bariatric surgery (n = 206) and at 6 months (n = 195), 12 months (n = 176), and 24 months (n = 149) after surgery. Time to completion, resting heart rate (HR), immediate posttest HR, and HR difference (resting HR minus posttest HR) were measured and musculoskeletal pain concerns, during and after the test, were documented. Data were adjusted for age, sex, race/ethnicity, baseline body mass index (calculated as weight in kilograms divided by height in meters squared), and surgical center (posttest HR and HR difference were further adjusted for changes in time to completion). Results Of the 206 adolescents with severe obesity included in the study, 156 were female (75.7%), the mean (SD) age was 17.1 (1.6) years, and the mean (SD) body mass index was 51.7 (8.5). Compared with baseline, significant improvements were observed at 6 months for the walk test time to completion (mean, 376 seconds; 95% CI, 365-388 to 347 seconds; 95% CI, 340-358; P Conclusions and Relevance These data provide evidence that bariatric surgery in adolescents with severe obesity is associated with significant improvement in functional mobility and in the reduction of walking-related musculoskeletal pain up to 2 years after surgery.

The objective of this study was to test a comprehensive model of biologic (pubertal status), family (communication and conflict), and psychological influences (behavioral autonomy) on diabetes management and glycemic control in a sample of youth (N = 226) with type 1 diabetes recruited during late childhood/early adolescence (ages 9–11 years). The study design was a prospective, multisite, multi-method study involving prediction of diabetes management and glycemic control 1 year post-baseline. The primary outcome measures included diabetes management behaviors based on the Diabetes Self-Management Profile (DSMP) administered separately to mothers and youth and glycemic control measured by glycated hemoglobin (HbA1c) obtained by blood samples and analyzed by a central laboratory to ensure standardization. Our hypothesized predictive model received partial support based on structural equation modeling analyses. Family conflict predicted less adequate glycemic control 1 year later (p < 0.05). Higher conflict predicted less adequate diabetes management and less adequate glycemic control. More advanced pubertal status also predicted less adequate glycemic control, but behavioral autonomy did not. Family conflict is an important, potentially clinically significant influence on glycemic control that should be considered in primary and secondary prevention in the management of type 1 diabetes in youth.

Purpose The purpose of this study was to describe the muscle activation patterns of the vastus lateralis (VL), medial hamstrings (MH) and lateral hamstrings (LH) associated with subjects that were anterior cruciate ligament (ACL) deficient and controls. Methods A total of 54 subjects participated in this study including 25 ACL deficient subjects subdivided into copers (n = 9) and non-copers (n = 16) using clinical criteria. Muscle activation patterns were recorded at 1000 Hz during an unanticipated side step cut task. The root mean square processed data (time constant 11 ms) were ensemble averaged from 20% of stance before heel strike to toe off. Using the first five harmonics of the Fourier Coefficients as features, muscle activation patterns were divided using a cluster analysis algorithm. Results A majority (76–93%) of control subjects used three muscle activation patterns for each muscle. The coper group preferentially used a particular VL and MH activation pattern >2 times more frequently than controls. The non-coper group also preferentially used a MH activation pattern >2 times more frequently than controls and utilized a unique MH and LH activation pattern, distinct from the copers and controls. Conclusions Specific muscle activation patterns distinguish subsets of subjects that are healthy and injured, suggesting possible patterns of muscle activation that contribute to coping status.