Reference Values For Children Research Articles

Simple and practical formulas for stage 1 hypertension reference values in children.

Simple and practical formulas for stage 1 hypertension reference values in children.

Nerve ultrasound reference values in children and adolescents: Echogenicity and influence of anthropometric factors including hand volume.

Nerve cross-sectional area (CSA) reference values in high-resolution ultrasound for children and adolescents are influenced by demographic and anthropometric factors such as age, height and weight. The influence of hand volume as an additional morphometric factor was evaluated and nerve echogenicity was analyzed in a prospective cross-sectional study. CSA were measured in 30 healthy children and adolescents from 2 to 17years in the median, ulnar, radial, tibial, peroneal and sural nerves. Height, weight, age, handedness and gender were recorded, the volume of the hands was measured using the water displacement method. The intra-nerve CSA variability (INV), left/right ratios and absolute differences were calculated. Age groups were compared by the Kruskal-Wallis test. The influence of demographic factors was analyzed using Spearman correlation and multiple linear regression. Echogenicity and fraction of black were determined for each nerve segment. Nerve CSA values were consistently lower than those reported for adults and correlated in all measured nerve sites with age, height, weight and hand volume. Weight showed the highest correlation coefficient (R = .95) with the best fitting model predicting CSA. Correlation coefficients were higher in a linear than in a logarithmic model. Ratios were stable, the absolute differences increased with age and were significantly different between age groups. Most nerves showed a mixed or hypoechogenic pattern in echogenicity analysis, hyperechogenicity is less frequently observed. Nerve CSA in children and adolescents is lower than in adults and increases proportionally during growth with a constant INV and left/right ratio in different age groups. Weight and age are predominant anthropometric factors predicting nerve size. Hand volume is correlated with nerve size, but does not predict CSA independently. Echogenicity can provide additional information on nerve structure.

Establishment and validation of reference values for abdominal skeletal muscle compartments in children

Sarcopenia, resulting from skeletal muscle loss, is a serious concern in children, for whom nutrition and physical activity are essential for growth. In sarcopenia research, the skeletal muscle mass is often obtained from computed tomography (CT) cross-sectional images in both adults and children; however, the method of evaluating skeletal muscle using CT, especially the area range to be measured, has not yet been validated in children. The aim of this study is to establish reference values for three compartments of the abdominal skeletal muscle area (aSMA) obtained from cross-sectional CT images, and to validate the differences among them by assessing correlations with physical development. We conducted a single-centre, retrospective, cross-sectional study and included patients aged 1-17 years who underwent abdominal CT at Chiba University Hospital from 2007 to 2020. Patients with chronic diseases such as malignant tumours and inflammatory bowel disease were excluded from the analysis. aSMA was obtained from CT cross-sections at the lumbar L3-L4 intervertebral disc level by dividing it into three compartments: the psoas muscle area (PMA), paraspinal muscle area (PSMA), and total skeletal muscle area (TSMA). Quartile regression curves by sex and muscle compartment were generated using non-crossover and nonparametric regression quantile estimation. The correlation between each compartment of aSMA with height and weight was assessed using Spearman's rank correlation coefficient. We analysed the abdominal CT images of 593 children (male: n=335, female: n=258) and generated curves predictive for the 5th, 25th, 50th, 75th, and 95th percentiles for each compartment of aSMA by sex. In patients aged 13 years and older, boys had significantly larger aSMA areas than girls in all three compartments. Among the three compartments, PSMA had the strongest correlation coefficient with height and weight for both boys and girls. We generated quantile regression curves for three aSMA compartments obtained from cross-sectional CT images and established reference values in children. PSMA values were most strongly correlated with height and weight among the three aSMA compartments.

Are glucose and insulin levels at all time points during OGTT a reliable marker of diabetes mellitus risk in pediatric obesity?

PurposeChildhood overweight and obesity associated with insulin resistance and metabolic syndrome represent the new global pandemic and the main causative factors for dysglycemia, prediabetes, and Type 2 Diabetes Mellitus (T2DM). Predictors, such as HOMA-IR, HOMA-β%, and QUICKI lack specific reference values in children. OGTT is a gold standard for glycometabolic assessment. Recently, a glycemic level higher than 155 mg/dl at + 60′ after glucose ingestion has been defined as a risk factor for T2DM in obese adolescents. We aim to analyze and correlate fasting insulin-resistance markers with OGTT results in overweight/obese children and adolescents.MethodsWe retrospectively evaluated glucose and insulin values during a 2-h OGTT every 30 min in 236 overweight/obese patients. Glucose values and insulin sum during OGTT were compared to glycometabolic indexes and different cut-off values for insulin sum.ResultsA 1-h glucose > 155 mg/dl and insulin sum > 535 microU/ml at all times during OGTT are the best predictors of diabetes risk in obese youths. A1-h glucose > 155 mg/dl is significantly associated with HbA1c > 5.7%, while no association was observed between HbA1c > 5.7% and glucose levels at baseline and 2 h. The ability of the standardized HOMA-IR to predict the prediabetes status is clearly lower than the total insulin sum at OGTT.ConclusionOur study demonstrates that also 1-h post-OGTT glucose, together with HbA1c, is an effective diabetes predictor.

Reference Values of Chest Expansion among Healthy Children: A Cross-sectional Study

Abstract Background and Objective: Examination of the chest wall movement during breathing provides valuable insight into the function of a person’s respiratory system. Chest mobility and lung function may be altered due to growth, body composition, and respiratory disease. Preliminary baseline values for measuring chest expansion were obtained for healthy adult Indians. However, because the rib configuration of children differs from that of an adult, reference values for children need to be established. Materials and Methods: In the present study, chest expansion was measured at three levels – second rib, fourth rib, and xiphisternum (R2, R4, and xiphisternum level which was marked at the lower end of the body of the sternum) – in 720 children aged 5–12 years using a nonstretchable measuring tape. The difference between chest circumference at maximum expiration and maximum inspiration was recorded as the value of chest expansion. Out of three, one best value and not an average value was considered a chest expansion measurement at each level. Results: Three subgroups were made: 5–7 years, 8–10 years, and 11–12 years. Results were documented and presented as mean and standard deviation for each subgroup. The reference values for chest expansion among healthy children in the age group of 5–12 years are 2.5 cm–3.2 cm at the R2 level, 3.1 cm–3.7 cm at the R4 level, and 3.8 cm–4.1 cm at the xiphisternum level. Conclusions: The chest expansion for different age groups among healthy children was different.

Assessment of Bone Health Using Dual-Energy X-Ray Absorptiometry (DEXA) And Its Association with Dietary Intakes, Serum Vitamin D Levels, and Anthropometric Measures in Healthy Urban Preschool Children.

To generate reference data for bone mineral content (BMC) and bone mineral density (BMD) measures among apparently healthy children aged 4-5 y and to study the relationship of BMC and BMD with age, sex, anthropometric measures, dietary intakes, and serum vitamin D levels. This cross-sectional study was conducted among 219 urban preschool children, aged 4.0-5.11 y. Bone health (BMC and BMD) was measured using dual energy X-ray absorptiometry (DEXA). Anthropometric parameters were measured using standard methodology. The 24-h dietary recall method was used to assess the dietary intake of the children. Serum vitamin D levels were assessed using the ELISA kit method. Percentiles for BMC and BMD for each age and sex were constructed using the lambda-mu-sigma (LMS) method. The mean BMD and BMC among children was 0.75 ± 0.04g/cm2 and 544.9 ± 87.6g, respectively, and were significantly different by age and sex category. The BMC and BMD values of boys and girls increased with age, with boys having significantly higher values. A significant positive correlation was observed for BMC and BMD with anthropometric measures and dietary intake of calcium, phosphorous, protein, zinc, and B vitamins. This study developed smoothed percentile curves for BMC and BMD in preschool children, which could be used as reference values for children from India.

Three-Dimensional Echocardiography Right Ventricular Volumes and Ejection Fraction Reference Values in Children: A North American Multicentre Study.

Three-dimensional echocardiography (3DE) evaluation of right ventricular (RV) volumes and ejection fraction (EF) is increasingly used for clinical serial assessments and management in children. This study aims to generate sex-specific reference values and z-score equations for RV volumetric parameters, independent of age and body size indices, derived from multiple populations across North America. We prospectively recruited 455 healthy children (ages 0 to 18 years) from 5 centres. 3DE of the RV were acquired using various vendors with analyses performed offline using vendor-independent software. 3DE datasets with all walls of the RV endocardium visible were included. We reported data on RV EF, and generated z scores for end-systolic volumes (ESV), end-diastolic volumes (EDV) and stroke volume (SV). Differences between the sexes were explored. Of 455 3DE datasets, 312 (68%) met imaging criteria for analysis. Median age was 10.1 years (interquartile ratio [IQR]: 5.6, 14.0) with 17% being younger than 3 years of age. The mean and standard deviation for RV EDV, ESV, and SV for male and female patients were reported. We provided a downloadable z-score calculator with height and weight as independent variables to facilitate clinical utility. Although statistically significant differences between male and female RVEF was present (female 52.9 ± 3.9% vs male 51.6 ± 3.5%, P= 0.006), after adjusting for age, height, and weight, the magnitude of difference was clinically insignificant. Sex-specific reference values for pediatric RV volumes and EF, and z-score equations were derived from children 3DE datasets across 5 centres in North America.

Sagittal Balance in Children: Reference Values of the Sacral Slope for the Roussouly Classification and of the Pelvic Incidence for a New, Age-Specific Classification

Background: The Roussouly classification, based on the functional parameter sacral slope (SS), describes the normal sagittal balance in adults and has proved useful for surgery. Reference values in children should be defined, since they are an important treatment target of conservative treatment. Moreover, during growth, there are few correlations between sagittal parameters, and we hypothesize that a new classification based on the anatomical parameter pelvic incidence (PI) could also be useful. We performed a cross-sectional study to identify the reference values for the Roussouly classification during growth and to develop a new classification based on PI in children. Methods: Correlations between sagittal parameters and age were searched in 222 healthy subjects at the first consultation (6–18 years old). A new classification, based on PI, and comprising three types, is defined and compared to the Roussouly classification. Results: With age, correlations among sagittal balance parameters increase, as well as SS and PI, but with different cut-offs. The distribution of Roussouly types do not correspond to that in adulthood; thus, we defined new reference cut-offs. We defined a PI-based classification in three types, not overlapping Roussouly’s. We found a uniform and balanced distribution of cases among the nine possible combinations. Conclusions: In children, we need to use new thresholds for the Roussouly types. The new classification based on PI is correlated with the Roussouly classification, but it is also clearly different. Future studies will determine its validity.

P 83 Nerve ultrasound cross-sectional area reference values in children from 2 to 17 years and their correlation with demographic and anthropometric data

Question: High-resolution ultrasound (HRUS) is of growing importance in the routine workup of disorders of the peripheral nervous system. However, reference values for children and adolescents are not available in most ultrasound laboratories. The correlation of cross-sectional area (CSA) values with demographic and anthropometric data has been analysed in adults, the exact influence of anthropometric data on nerve ultrasound reference values in children and adolescents is discussed in the literature (1,2). The present prospective observational study analyses the influence of height, weight, age, gender, and the volume of the hands on CSA values in nerve HRUS in healthy children and adolescents from 2 – 17 years. Methods: CSA were measured in 30 healthy children and adolescents from 2 – 17 years in the median, ulnar and radial nerves in the upper extremity and in the tibial, peroneal and sural nerve in the lower extremity at different nerve sites. Height, weight, age, handedness and gender were recorded, the volume of the hands was measured using the water displacement method. The intra-nerve CSA variability and the side-to-side difference ratio of the intra-nerve CSA variability (SSDIVA) for the median, ulnar and tibial nerves was calculated. Normal distribution of the data was tested using the Shapiro-Wilk test. Spearman’s rho and Pearson's correlation coefficient was calculated for CSA, intra-nerve CSA variability, SSDIVA and age, weight, gender, hand volume. Multiple linear regression analysis with backward exclusion was used to calculate the best model predicting CSA. Model selection was based on the Akaike information criterion (AIC). Results: Nerve CSA values were consistently lower than those reported for adults and increased in all measured nerve sites with increasing age, height and weight (see Figure 1 for the ulnar nerve and age groups). This increase had a tendency to levell off at an age of 14 – 17 years. The highest correlation coefficients and best-fitting model predicting CSA were found for the variable “weight”. Correlation coefficients were higher in a linear than in logarithmic model (Figure 2). Hand volume showed a positive correlation with age, weight and nerve CSA. Conclusions: Normal values for CSA in high-resolution nerve ultrasound should be adapted for children and adolescents. Demographic data such as height, weight and age can be considered to stratify and adjust normal values to the individual child's development. Corresponding with the findings of Druzhinin (1) and in contrast to the results of Schubert (2) our data suggest that weight, and not age, has the maximum influence on nerve CSA measurements.

Validation of the Masimo O3™ regional oximetry device in pediatric patients undergoing cardiac surgery.

We assessed the accuracy of Masimo O3™ regional cerebral oxygen saturation (rSO2) readings by comparing them with reference values and evaluated the relationship between rSO2 and somatic tissue oxygen saturation (StO2) in children undergoing cardiac surgery. After anesthesia induction, pediatric sensors were applied to the forehead and foot sole, and rSO2 and StO2 values were monitored continuously. Before cardiopulmonary bypass (CPB), FIO2 was set to 0.2, 0.5, and 0.8 serially every 15min. After CPB, FIO2 was reversed. The reference values (SavO2) were calculated by combining arterial (SaO2) and central venous oxygen saturation (SvO2) readings from the arterial and central lines, respectively (0.7 [Formula: see text] SvO2 + 0.3 [Formula: see text] SaO2). In total, 265 pairs of rSO2/StO2 and SavO2 from 49 patients were analyzed. The bias, standard deviation (SD), standard error (SE), and root mean squared error (RMSE) of rSO2 were 2.6%, 4.5%, 0.3%, and 4.3%, respectively. The limits of agreement ranged from -6.3% to 11.6%. Trend accuracy analysis yielded a relative mean error of -1.4%, with an SD of 4.3%, SE of 0.2%, and RMSE of 3.9%. According to multiple linear regression analysis, the application of CPB, FIO2, Hb level, and tip location of the central venous catheter influenced the bias (all P < 0.05). Furthermore, the correlation between rSO2 and StO2 was weak (r = 0.254). rSO2 readings by the Masimo O3™ device and pediatric sensor had good absolute and trending accuracies with respect to the calculated reference values in children undergoing cardiac surgery. rSO2 and StO2 cannot be used interchangeably.Clinical trial registration http://clinicaltrials.gov (number: NCT04208906).

Impact of COVID-19 on serum melatonin levels and sleep parameters in children

Background/aim This study aimed to analyze the serum melatonin levels and changes in sleep patterns in pediatric patients with coronavirus disease 2019 (COVID-19).Materials and methods This study was designed as a descriptive, cross-sectional study. Serum melatonin levels and sleep parameters of children with the diagnosis of COVID-19 who had mild and moderate disease (i.e., COVID-19 group) were compared with those of children admitted with non-COVID-19 nonspecific upper respiratory tract infection (i.e., control group). The sleep disturbance scale for children (SDSC) questionnaire was applied to the participants› primary caregivers to analyze their sleep patterns at present and six months before symptom onset and to investigate the impact of COVID-19 on sleep patterns. Results The entire study cohort consisted of 106 patients. The COVID-19 group included 80 patients, while the control group consisted of 26 patients. The mean serum melatonin levels were 136.72 pg/mL and 172.63 pg/mL in the COVID-19 and control groups, respectively (p = 0.16). There was no significant difference between the groups in terms of 6 subcategories of the SDSC questionnaire regarding the present time and 6 months before symptom onset. The total SDSC scores were also similar in two different evaluation time points described above (p = 0.99).ConclusionsWe conclude that COVID-19 did not impact the sleep parameters of children. Serum melatonin levels of all patients were higher than the reference range; however, they were higher in the non-COVID-19 patient group than the COVID-19 group. Since serum melatonin levels were higher than the reference values in children with COVID-19, and this disease is significantly less morbid in children, melatonin may have protective effects against COVID-19.

Assessment of Dysphonia in Children with Pompe Disease Using Auditory-Perceptual and Acoustic/Physiologic Methods.

Bulbar and respiratory weakness occur commonly in children with Pompe disease and frequently lead to dysarthria. However, changes in vocal quality associated with this motor speech disorder are poorly described. The goal of this study was to characterize the vocal function of children with Pompe disease using auditory-perceptual and physiologic/acoustic methods. High-quality voice recordings were collected from 21 children with Pompe disease. The Grade, Roughness, Breathiness, Asthenia, and Strain (GRBAS) scale was used to assess voice quality and ratings were compared to physiologic/acoustic measurements collected during sustained phonation tasks, reading of a standard passage, and repetition of a short phrase at maximal volume. Based on ratings of grade, dysphonia was present in 90% of participants and was most commonly rated as mild or moderate in severity. Duration of sustained phonation tasks was reduced and shimmer was increased in comparison to published reference values for children without dysphonia. Specific measures of loudness were found to have statistically significant relationships with perceptual ratings of grade, breathiness, asthenia, and strain. Our data suggest that dysphonia is common in children with Pompe disease and primarily reflects impairments in respiratory and laryngeal function; however, the primary cause of dysphonia remains unclear. Future studies should seek to quantify the relative contribution of deficits in individual speech subsystems on voice quality and motor speech performance more broadly.

Oesophageal pH-Impedance for the Diagnosis of Gastro-Oesophageal Reflux Disease: Validation of General Population Reference Values in Children with Chronic Neurological Impairments.

Diagnosis of gastro-oesophageal reflux disease (GORD) in children with chronic neurological impairment (NI) remains a clinical challenge. The study aimed to validate the relevance of the reference values used to assess gastro-oesophageal reflux (GOR) in children with NI and to determine the optimal cut-off level of the pH-impedance parameter with the best predictive value for outcomes associated with endoscopic assessments of the oesophagus. Sixty-seven children (32 male, 35 female; age: interquartile range, 5 years 6 months–14 years 10 months; median, 11 years 3 months) with NI were prospectively recruited for the study. The exclusion criteria were previous fundoplication and lack of consent for the study. All patients underwent evaluations for GOR disease, including pH-impedance and gastroscopy. Based on endoscopy, oesophagitis was diagnosed in 22/67 children (32.8%); 9/67 (13.4%) were classified as having Hetzel–Dent grade III or IV. GOR was present in 18/67 children (26.9%), as determined by pH-impedance. Patients with endoscopic lesions had a significantly higher number of total reflux (p = 0.0404) and acidic episodes (p = 0.0219). The total number of reflux episodes, with a cut-off level of 44 episodes, was the pH-impedance parameter most strongly predictive of the presence of lesions in gastroscopy (specificity: 50%, sensitivity: 73%). These findings suggest that endoscopic lesions may be present in children with chronic NI with a low number of GOR episodes, as recorded by pH-impedance. The use of standardised reference norms determined for the general population may underestimate GOR episodes in this group of patients.

Variation in blood count parameters of children aged 5 to 11 years in Abidjan, Côte d'Ivoire

Background: In Côte d’Ivoire, as in most developing countries, the reference values of hematological indices currently in use come from data collected from populations living in industrialized countries. The aim of this study was to determine variations in the child's blood count in Cote d'Ivoire. Materials and Methods: This descriptive cross-sectional study has focused on 310 children (172 girls and 138 boys) aged 5 to 11 years selected from three municipalities of Abidjan. Blood samples were taken from each child in order to assess the parameters of the blood count. Results: The results revealed that the means of the different hematological parameters (red blood cells, hemoglobin, hematocrit, white blood cells, neutrophils, eosinophils, monocyte, mean corpuscular volume, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration) were in accordance with the normal physiological reference values from the literature apart lymphocyte. The rate of lymphocytes (51.3 ± 0.5) was higher overall. All the parameters did not indicate significant differences between girls and boys (p &gt; 0.05) except mean corpuscular volume, and mean corpuscular hemoglobin that were statistically different by sex (p &lt; 0.05). The percentage of having a rate of haemoglobin lower than 11.5 decreased significantly (p˂0.005) when the age increased. In addition, the rate of hemoglobin and hematocrit increased slightly starting from the age of 8 years. There is a significant difference (p &lt; 0.05) in hemoglobin level between girls and boys in the age group of 9 years. Leukopenia is observed in a minority of children in the age groups of 5, 6, 7, 8, and 10 years. Conclusion: Some hematological parameters were different from other data published in the literature, which suggested a local development of reference values for children.

Reference Values for the Six Minute Walk Test in Children with Juvenile Idiopathic Arthritis

Aims To (1) describe six-minute walk test (6MWT) reference values for children with Juvenile Idiopathic Arthritis (JIA) and (2) explore predictors of 6MWT distance. A secondary objective was to determine how 6MWT distances of children with JIA compare to those of children without JIA reported in the literature. Methods Demographic, clinical, height, weight and 6MWT data were extracted from clinical records of 120 children with JIA (70.8% female, 12.4 ± 3.2 years) who attended a follow-up rheumatology clinic. A total of 272 6MWTs were included in the analyses. Linear mixed effects modeling was used to determine the relationship between predictive variables and 6MWT distance. 6MWT distances were compared to predicted values using published equations for estimating 6MWT distances in children without JIA. Results Height, weight, and age were predictive of 6MWT distance (R2 = 0.62). Mean 6MWT distances for children with JIA were lower than those reported for children without JIA (p < 0.001). Mean 6MWT distance was 84% and 78% of predicted values for children without JIA. Conclusion The reference values and associated predictive model have application for assessing exercise capacity in children with JIA.

Body composition monitoring in children and adolescents: reproducibility and reference values

There is an increasing need for suitable tools to evaluate body composition in paediatrics. The Body Composition Monitor (BCM) shows promise as a method, but reference values in children are lacking. Twenty children were included and measured twice by 4 different raters to asses inter- and intra-rater reproducibility of the BCM. Reliability was assessed using the Bland-Altman method and by calculating intraclass correlation coefficients (ICCs). The intra-rater ICCs were high (≥ 0.97) for all parameters measured by BCM as were the inter-rater ICCs for all parameters (≥ 0.98) except for overhydration (0.76). Consequently, a study was set up in which BCM measurements were performed in 2058 healthy children aged 3–18.5 years. The age- and gender-specific percentile values and reference curves for body composition (BMI, waist circumference, fat mass and lean tissue mass) and fluid status (extracellular and intracellular water and total body water) relative to age were produced using the GAMLSS method for growth curves.Conclusion: A high reproducibility of BCM measurements was found for fat mass, lean tissue mass, extracellular water and total body water. Reference values for these BCM parameters were calculated in over 2000 children and adolescents aged 3 to 18 years.What is Known• The 4-compartment model is regarded as the ‘gold standard’ of body composition methods, but is inappropriate for regular follow-up or screening of large groups, because of associated limitations.• Body Composition Monitor® is an inexpensive field method that has the potential to be an adequate monitoring tool.What is New• Good reproducibility of BCM measurements in children provides evidence to use the device in longitudinal follow-up, multicentre and comparative studies.• Paediatric reference values relative to age and sex for the various compartments of the body are provided.

Pediatric reference values of TSH should be personalized according to BMI and ethnicity.

The need for personalization of the reference values of thyroid function tests has been previously suggested. We aimed at determining TSH reference values in a large cohort of children according to age, sex, BMI, and ethnicity. A population-based cohort study. The study cohort included 75 549 healthy children aged 5-18 years. Data analyzed included age, gender, TSH, FT4 levels, BMI and ethnicity. Multivariate logistic regression analysis examined the associations between the study parameters. TSH in the Jewish population is lower than in the non-Jewish population (median: 2.1 IU/L (IQR: 1.5) vs 2.2 IU/L (IQR: 1.5), P < 0.0001). TSH is significantly affected by BMI for children defined as underweight, normal weight, overweight or obese, levels increased as weight diverged from the normal range (median levels: 2.1 IU/L (IQR: 1.4), 2.0 IU/L (IQR: 1.3), 2.1 IU/L (IQR: 1.4), 2.4 (IQR: 1.5), respectively, P < 0.001). The 2.5 percentile is affected by gender and BMI (P < 0.02 and P < 0.001, respectively), while the 97.5 percentile is affected by ethnic origin and BMI (P < 0.001 for both). New TSH reference intervals (RI) adjusted according to BMI and ethnicity are suggested. Comparison of the old and new RI demonstrate the significance of RI personalization: 25.1% of the children with TSH levels above the old RI are within the new RI, while 2.3% of the children who were in the old RI are below the new RI. TSH reference values in children are affected by BMI and ethnicity. Reference values should be individualized accordingly to improve future clinical decision-making and treatment.

Standardized IOS Reference Values Define Peripheral Airway Impairment-Associated Uncontrolled Asthma Risk Across Ethnicity in Children

Although clinically useful in identifying peripheral airway impairment (PAI), impulse oscillometry (IOS) has not received universal acceptance. This may be due to variable cutoff points, and the perception that available standardized reference values may not be clinically relevant in all populations. To establish the relationship between PAI, based on standardized IOS reference values, and uncontrolled asthma as well as interchangeability between Hispanic and white reference algorithms. IOS reference values were established for upper and lower limits of normal (>95th and <5th percentile, respectively) using published algorithms in Hispanic and white children. Values exceeding normal limits (PAI) were compared in those uncontrolled and controlled for significance of differences. Probability estimates and odds ratio of uncontrolled asthma were determined for R5, R5-R20, AX, and X5 using adjusted generalized estimating equation analyses. Intraclass correlation coefficients determined interchangeability of Hispanic and white reference algorithm values. Those with uncontrolled asthma had significantly greater PAI and a higher frequency of PAI than those well controlled (P < .05), whereas odds of uncontrolled asthma increased with increasing PAI (P < .001) for all IOS measures, particularly for X5, where odds ratios ranged from 2.70 to 11.01.There was good to excellent (>70%) agreement between Hispanic and white algorithms, except for R5-R20 (<70%). PAI, defined by IOS reference values, not central airway markers (R20), is consistently related to the risk of uncontrolled asthma. This is true whether using Hispanic or white reference algorithms. Thus, standardized reference values in children offer the clinician readily available IOS cutoff points that are clinically relevant across ethnicity.

Abdominal Muscular Strength Endurance: Normative Reference Values for Children 11 to 15 Years of Age

Abdominal Muscular Strength Endurance: Normative Reference Values for Children 11 to 15 Years of Age

Safety and Efficacy of Peroral Endoscopic Myotomy for the Treatment of Achalasia in Children: A Large Multi-Center Study

Background: Peroral endoscopic myotomy (POEM) has showed excellent results for the treatment of achalasia in adults, but studies of POEM for children are limited. In this study, we comprehensively analyzed outcomes of POEM in children and compared with those in adults in a large multi-center study. Methods: Between August 2010 and December 2015, records of consecutive patients with achalasia who underwent POEM at three tertiary centers were reviewed. A total of 130 children were included in this study. The primary outcomes of perioperative outcomes and clinical follow-up data were analyzed. Findings: One child (0*8%) experienced technical failure. Five children (3*8%) had major adverse events, including one with pneumothorax requiring drainage, two with delayed mucosa barrier failure, one with readmission, and one with vital sign instability. Both post-POEM Eckardt score and median LES pressure were significantly lower than their pre-POEM reference values in children (0*7 vs 7*4; 7*0 vs 27*1 mmHg; both P 0*05). Kaplan-Meier analysis showed that the risk of clinical failure was lower in children than adults (log-rank test, hazard ratio=0*37, 95% confidence interval 0*15-0*91, P=0*023). Interpretation: POEM can be safely and effectively performed in children with achalasia. In addition, it produces a better clinical response during long-term follow-up compared with that in adults. Funding: This study was supported by grants from the National Natural Science Foundation of China (81873552, 81470811, 81570595, and 81670483), Major Project of Shanghai Municipal Science and Technology Committee (18ZR1406700, 16411950400, 16DZ2280900), Chen Guang Program of Shanghai Municipal Education Commission (15CG04), and Outstanding Young Doctor Training Project of Shanghai Municipal Commission of Health and Family Planning (2017YQ026), and the Project of Shanghai Municipal Commission of Health and Family Planning (SHDC12016203). Declaration of Interest: All authors have none to declare. Ethical Approval: This retrospective study was approved by the local ethics committee. Written informed consent was obtained before POEM from patients or their caretakers if patients were <16 years of age.