Percentile Reference Research Articles

Reference Ranges and Z-Score Equations for 19 Fetal Cardiac Biometry Structures From 18 to 34 Weeks' Gestation.

To determine equations for calculating the Z-scores of fetal cardiac structures between 18+0 and 34+6 weeks of gestation, create percentile reference tables and curves for the structures, and assess the intra- and inter-observer reproducibility of the measurements. A cross-sectional study was conducted involving 340 normal fetuses from singleton pregnancies between 18 and 34 weeks of gestational age (GA). Nineteen cardiac structures were evaluated: diameters of the mitral, tricuspid, aortic, and pulmonary valve annuli; length, diameter, and area of the left and right ventricles; cardiac area and circumference; and diameters of the ascending aorta, aortic isthmus, main pulmonary artery, right pulmonary artery, left pulmonary artery, and ductus arteriosus. Regression analysis was performed to determine the equations for the mean and standard deviation of all structures using GA, biparietal diameter (BPD), and femur length (FL) as independent variables. All equations had high coefficients of determination (R2). The best performance was achieved using the GA (R2 .819-.944), followed by FL (R2 .813-.937) and BPD (R2 .792-.934). The structure that demonstrated the highest R2 was the cardiac circumference and the smallest was the ductus arteriosus. Reference tables of percentiles 1, 5, 10, 50, 90, 95, and 99, and reference curves of Z-scores were created for all 19 cardiac structures, depending on the GA. All measurements demonstrated good and excellent reproducibility with an inter-observer intraclass correlation coefficient (ICC) of 0.774-0.972 and intra-observer ICC of 0.938-0.993. Equations were produced to calculate Z-scores as well as percentile tables and curves for 19 fetal heart structures. All the measurements demonstrated good reproducibility.

Argentine reference charts for head circumference from birth to 19 years of age.

Introduction. Head circumference (HC) is an indicator of brain growth; growth charts are necessary to determine normal or pathological variations. Objectives. To present the first Argentine HC reference charts between birth and 19 years of age and to compare them with the Nellhaus charts, which have been used in our country to date. Population and methods. These references were developed based on combined data from the National Survey on Nutrition and Health of 2018 and cross-sectional studies conducted between 2004 and 2007 in the provinces of Buenos Aires and La Pampa, which included 8326 healthy children and adolescents. Growth curves were adjusted using the LMS method. To assess the differences between these reference charts and the Nellhaus charts, at different ages, the 2nd, 50th, and 98th percentiles were plotted. Results. HC showed a variable increase in size with age, which was greater in the first years of life, and a slight increase at puberty. The values for the 98th percentile of the Argentine reference charts werehigher than those of the Nellhaus charts at all ages. The values for the 2nd percentile of the national reference were lower than those of the Nellhaus charts during the first 2 years of life, similar between 3 and 7 years of age, and higher after this age. Conclusions. The Argentine curves adequately describe the growth pattern of HC. The differences found with the Nellhaus charts may be attributed to secular changes.

Potential effects of attention deficit hyperactivity disorder medication on body height and body weight in a longitudinal pediatric cohort study, the LIFE Child study.

Purpose: To investigate the potential impact of drugs for the treatment of attention deficit hyperactivity disorder (ADHD) on body weight and height in children and adolescents from the LIFE ('Leipzig Research Centre for Civilization Diseases', Leipzig, Germany) Child cohort. Methods: We included 2,115 participants aged ≥6 to <18.25 years who attended the LIFE study center between 2011 and 2020 in our analysis, of whom 48 used ADHD drugs. Anthropometric and medication data from baseline to the third follow-up visit were available for 659 participants. Body height and body weight measurements were subsequently converted to z-scores. A repeated measures analysis of variance (ANOVA) was performed on the z-scores of both ADHD drug users and non-users to determine potential trends in body weight and body height from baseline to the 3 rd annual follow-up. Results: At the last visit with ADHD drug use of the 48 ADHD drug users, 40% (19/48) of the children and adolescents were below the 25 th reference percentile for weight. Z-scores for body height declined from baseline to the 3rd annual follow-up in individuals who used ADHD drugs (n=10; Differencemeans =-0.310; p=0.002) compared to non-users (n=649; Differencemeans =0.102; p<0.001). Body weight also decreased from baseline to 3rd follow-up in the ADHD drug group (n=10; Differencemeans =-0.473; p<0.001) compared to the non-user group (n=649; Differencemeans =0.015; p=0.161). Conclusion: We observed a potential tendency towards lower Z-scores for body height and body weight in individuals taking ADHD medication for an extended period compared to the corresponding age- and sex-matched populations.

Establishment of IGF-1 and IGFBP-3 continuous reference percentiles from data of healthy children using three kinds of immunoassay systems

Background and aimsAppropriate continuous reference intervals (RIs) for serum insulin-like growth factor 1 (IGF-1) and insulin-like growth factor-binding protein 3 (IGFBP-3) are important for diagnosing growth hormone deficiency or excess. Material and methodsWe retrospectively reviewed serum IGF-1 and IGFBP-3 levels in Korean children aged 0–17 years who were diagnosed as healthy during a short stature workup in the outpatient clinics of three hospitals. IGF-1 and IGFBP-3 levels were measured using various immunoassays, including Liaison XL for IGF-1, an immunoradiometric assay (IRMA) for IGFBP-3 (n = 5522), and Immulite 2000 (n = 3036) and cobas e801 (n = 314). We established RIs from the 2.5th to 97.5th percentile RI curves using the lambda–mu–sigma (LMS) method for each sex group. ResultsPediatric serum continuous IGF-1 and IGFBP-3 reference percentiles by LMS method were found to be immunoassay method-dependent, but aligned relatively well with the manufacturers’ RIs. IGFBP-3 levels displayed notable discrepancies among the different immunoassay methods. ConclusionAge- and sex-specific pediatric LMS based continuous reference intervals are method dependent and they should be calculated for dynamic parameters that show variations throughout childhood.

The Small Step Early Intervention Program for Infants at High Risk of Cerebral Palsy: A Single-Subject Research Design Study.

Background/Objectives: Early interventions for infants at high risk of cerebral palsy (CP) are recommended, but limited evidence exists. Our objective was, therefore, to evaluate the effects of the family-centered and interprofessional Small Step early intervention program on motor development in infants at high risk of CP (ClinicalTrials.gov: NCT03264339). Methods: A single-subject research design was employed to investigate participant characteristics (motor dysfunction severity measured using the Hammersmith Infant Neurological Examination (HINE) and Alberta Infant Motor Scale (AIMS) at three months of corrected age (3mCA) related to intervention response. The repeated measures Peabody Developmental Motor Scales-2 fine and gross motor composite (PDMS2-FMC and -GMC) and Hand Assessment for Infants (HAI) were analyzed visually by cumulative line graphs, while the Gross Motor Function Measure-66 (GMFM-66) was plotted against reference percentiles for various Gross Motor Function Classification System (GMFCS) levels. Results: All infants (n = 12) received the Small Step program, and eight completed all five training steps. At two years of corrected age (2yCA), nine children were diagnosed with CP. The children with the lowest HINE < 25 and/or AIMS ≤ 6 at 3mCA (n = 4) showed minor improvements during the program and were classified at GMFCS V 2yCA. Children with HINE = 25-40 (n = 5) improved their fine motor skills during the program, and four children had larger GMFM-66 improvements than expected according to the reference curves but that did not always happen during the mobility training steps. Three children with HINE = 41-50 and AIMS > 7 showed the largest improvements and were not diagnosed with CP 2yCA. Conclusions: Our results indicate that the Small Step program contributed to the children's motor development, with better results for those with an initial higher HINE (>25). The specificity of training could not be confirmed.

O56 NIGHTTIME BLOOD PRESSURE REFERENCE VALUES FOR AMBULATORY BLOOD PRESSURE MONITORING AND THEIR RELATIONSHIP WITH AGE

Background and Objective: Nocturnal hypertension is characterized by elevated blood pressure (BP) levels during sleep (systolic blood pressure [SBP]&gt;120 mmHg or diastolic blood pressure [DBP]&gt;70 mmHg) as measured by 24-hour ambulatory blood pressure monitoring (24-h ABPM) (ESH 2023 guidelines). With aging, there is a gradual decline in renal function and vascular health, leading to changes in BP patterns. This study seeks to evaluate the necessity of age-specific cutoff points in defining hypertension, particularly during nocturnal hours. Methods: A cross-sectional study was conducted, involving 3,220 patients without hypertension, defined by 24-hour BP values, who were not using any antihypertensive medications and were referred for 24-h ABPM. Patients with a body mass index (BMI) ≥30 kg/m2 were excluded. The sleep period was defined as spanning from midnight to 6 am. Reference percentiles were established and juxtaposed with standard references. To determine the significance of age-specific cutoff points for defining nocturnal hypertension, the ESH 2023 reference was compared with the 95th percentile (P95) for age. Results: Among the participants, 64.6% were female, with an average age of 51.0±15.0 years, BMI of 25.0±2.7 kg/m2, nocturnal SBP of 106.4±9.0 mmHg (P95=121.8 mmHg), and nocturnal DBP of 66.0±5.0 mmHg (P95=74.3 mmHg). Normal distribution was observed for both SBP and DBP (Jarque Bera test). Nocturnal SBP exhibited a “J” shaped curve concerning age, whereas the average DBP remained relatively stable. Significant differences were noted for SBP across different age groups (P value &lt;0.00001). Proposed cutoff points for mean nocturnal SBP were suggested as follows: i) P95 &lt;60 years=120 mmHg; ii) P95 60-70 years=125 mmHg; and iii) P95 &gt;70 years=130 mmHg (Figure). A reference of 75 mmHg was proposed as the cutoff point for mean nocturnal DBP. Conclusions: The study highlights age-related variations in the P95 of mean nocturnal SBP, while DBP remains relatively stable across age groups. Consequently, we propose new cutoff points for defining these parameters.

HEMATOLOGY AND BIOCHEMISTRY REFERENCE INTERVALS FOR FREE-LIVING ADULT LESSER KESTRELS (FALCO NAUMANNI) IN SOUTHERN ITALY.

The lesser kestrel (Falco naumanni) is a small falcon with a Euro-Central and Asian-Mediterranean range wintering in sub-Saharan Africa. In the second half of the 20th century, the European population experienced a steep decline and was classified as at risk; thus, its biological and ecological aspects have been widely investigated. Nonetheless, data on hematology and plasma chemistry are not yet available. Therefore, hematology and biochemistry parameters were investigated in a sampling population of clinically healthy lesser kestrels (21 female and 10 male adults) from an Italian rescue center during breeding season, estimating the 95% (2.5 - 97.5th percentile) reference intervals (RI) for standard tests based on either parametric or robust statistical methods. The effect of sex on the referenced parameters was also tested and showed no statically significant differences. The established 95% RI highlighted values comparable with those of other similar raptors such as American kestrel (Falco sparverius) and peregrine falcon (Falco peregrinus). As the first recorded hematology and serum chemistry RI, these clinical data could support conservation efforts and clarify the effects of various environmental and ecological factors on the clinical and health status of lesser kestrels, although they should be reinforced with further data from healthy wild animals.

Abstract MP19: Hypertension Prevalence Among Youth aged 8–19 years in a National Survey — United States, 2017–2020

Hypertension in youth tracks into adulthood and has long-term negative health effects. In 2017, the American Academy of Pediatrics released new Clinical Practice Guidelines on pediatric hypertension. The guidelines updated blood pressure (BP) thresholds and age-sex-height percentile references for youth 1–17 years. Pediatric hypertension prevalence estimates since the new guideline are lacking. This study aims to provide the latest nationally representative prevalence estimates of elevated BP and hypertension in youth aged 8–19 years, total and stratified by age group, sex, race and ethnicity, and body mass index (BMI) category. For adolescents aged 13–17 years, both percentile-based thresholds and adult BP thresholds are available in the guidelines. We therefore compared adult BP thresholds for elevated BP (120–129/&lt;80 mmHg) and hypertension (≥130/≥80 mmHg) with percentile thresholds in adolescents. We used data from 2017–March 2020 National Health and Nutrition Examination Survey to obtain a sample of 2600 youth after excluding those with no BMI or BP measures. Prevalence estimates of elevated BP and hypertension were 8.7% (95% CI: 6.9-10.6) and 5.4% (95% CI: 4.0-6.7), respectively. Estimates were higher among males and increased with age (Table). Youth with severe obesity had the highest prevalence of hypertension. Hispanic youth had the lowest prevalence of elevated BP. In adolescents, elevated BP prevalence was similar using percentile thresholds (11.9%, 95% CI: 9.3-15.1) and the adult threshold (10.8%, 95% CI: 8.5-13.7). Hypertension prevalence in adolescents was also similar for percentile thresholds (4.8%, 95% CI: 3.1-7.6) and the adult threshold (4.8%, 95% CI: 2.0-7.5). Our findings suggest ongoing concern of elevated BP and hypertension among youth in the US. Either percentile or adult based thresholds for determining high BP could be used among adolescents by researchers. Knowledge of current national estimates can inform policies and interventions to support cardiovascular health in youth.

Preserved prenatal lung growth assessed by fetal MRI in the omicron-dominated phase of the SARS-CoV-2 pandemic.

With SARS-CoV-2 evolving, disease severity and presentation have changed due to changes in mechanisms of entry and effector site as well as due to effects of vaccination- and/or infection-acquired immunity. We re-assessed fetal lung pathology in pregnancies with uncomplicated SARS-CoV-2 infections during the late, omicron-dominated pandemic phase to inform disease understanding and pregnancy consultation. In this case-control study, fetal lung volumes were assessed by fetal MRI in 24 pregnancies affected by mild maternal SARS-CoV-2 infection during the omicron-dominated pandemic phase with prevailing immunity through vaccination and/or prior SARS-CoV-2 infection. Fetal lung volumes (normalized to estimated fetal weight) in 24 pregnancies (GA 33.3 ± 3.8, 12 female fetuses) following mild, uncomplicated SARS-CoV-2 infection did not differ significantly from both, published reference values (96.3% ± 22.5% of 50th percentile reference values, p = 0.43), or fetal lung volumes of a site-specific, non-COVID control group (n = 15, 94.2% ± 18.5%, p = 0.76). Placental assessment revealed no group differences in thrombotic changes or placental heterogeneity (p > 0.05, respectively), and fetal lung volume did not correlate with placental heterogeneity when adjusting for gestational age at scan (p > 0.05). Assessment of fetal lung volume by MRI revealed unaffected lung growth in pregnancies affected by uncomplicated SARS-CoV-2 infection in the omicron-dominated pandemic phase in the presence of prevailing hybrid immunity. This finding contrasts sharply with the observed reduction in fetal lung volume following maternal alpha-variant infection in the pre-vaccination era and might reflect tropism- as well as immunity-related effects. Question: Is fetal lung development affected by mild maternal SARS-CoV-2 infection during the omicron-dominated phase of the pandemic? Fetal lung volume in 24 affected pregnancies did not differ significantly from published reference values or fetal lung volumes in 15 site-specific, non-COVID-affected control pregnancies. Preserved fetal lung volume following mild maternal SARS-CoV-2 infection during the omicron-dominated phase contrasts with previous findings of reduced volume in unvaccinated pregnancies during the alpha-dominated pandemic phase. These observations might reflect tropism- as well as immunity-related effects.

The reference curves of percentile for the length and head circumference of infants aged 0–1 year in Hainan Province, China

We first established percentile reference curves for infant length and head circumference in Hainan Province based on gender and age in months and compared them with the 2022 national standards and World Health Organization (WHO) standards. This cross-sectional survey involved 2736 infants (1471 boys and 1265 girls) in 18 cities and counties in Hainan Province. Standardized instruments were used to measure head circumference and length. Reference values for Hainan infants' length and head circumference were determined using the LMS method. Curves were generated using the LMS Chart Maker software. According to the newly established reference curves, the length and head circumference of Hainan infants exhibited a consistent trend of steady growth. However, the average head circumference was below the 2022 national reference values and WHO standards. The mean length was lower than the new national reference values but roughly consistent with the WHO standards. Differences exist in infant length and head circumference in Hainan compared to national and global averages. To enhance infant length and head circumference growth, the health department should encourage exclusive breastfeeding for the first 6 months, ensure infants' sleep needs at night, and promote the regularity of vitamin D supplementation during the perinatal period.

The study of vaginal wall thickness in adults based on histopathological measurements

To accurately measure the vaginal mucosa thickness across different age groups using histopathologic techniques and investigate the factors that may influence the thickness changes. This study aims to provide clinicians with objective evidence of variations in vaginal mucosal thickness, facilitating personalized medical decisions for patients. A retrospective analysis was conducted on clinical data from 348 patients who underwent local vaginal wall resection at the West China Second University Hospital, Sichuan University, from January 2021 and May 2022. The thickness of vaginal mucosa, epithelium and lamina propria was measured precisely under the microscope. And the 10th, 25th, 50th, 75th, and 90th percentile values of vaginal mucosa thickness across different age groups were counted and charted a dot-line plot. The percentile values for vaginal mucosa thickness exhibited a decreasing trend with increasing age; vaginal mucosa thickness showed significant correlations with times of delivery (P = 0.031) and age (P < 0.001), both of which were negatively associated. And vaginal mucosa thickness demonstrated no significant correlation with body mass index (BMI) (P = 0.325), times of abortions (P = 0.511), times of gestation (P = 0.101), menstrual cycle (P = 0.533), or types of delivery (P = 0.056); epithelial thickness showed significant associations with age (P < 0.001) and types of delivery (P = 0.017), both of which were negative correlations. Moreover, BMI (P = 0.429), times of abortions (P = 0.764), delivery (P = 0.079), gestation (P = 0.475), and menstrual cycle (P = 0.950) were nonassociated with epithelial thickness; lamina propria thickness displayed a significant correlation only with age (P = 0.002), and there were no obvious correlations observed between lamina propria thickness and BMI (P = 0.374), times of abortion (P = 0.417), delivery (P = 0.053), gestation (P = 0.101), types of delivery (P = 0.132) and menstrual cycle (P = 0.495). Moreover, when the age segmentation was thresholded at 35 and 50 years, both epithelial thickness and vaginal mucosa thickness were significantly correlated with age (P < 0.05). Lamina propria thickness was associated with age when the age threshold was set at 35 years (P = 0.007), whereas it showed no strong link with age when the age threshold was 50 years (P = 0.072). This study has innovatively established percentile reference values for vaginal mucosa thickness based on histopathology, furnishing clinicians with objective evidence of variations in vaginal mucosal thickness to facilitate personalized medical decisions for patients. The findings demonstrated a strong link between vaginal mucosa thickness and age, with epithelium likely playing a predominant role, while the association with lamina propria appeared to be less significant. Further research involving a larger sample size is warranted to elucidate the potential relationship with the lamina propria.

Reference intervals and percentiles for soluble transferrin receptor and sTfR/log ferritin index in healthy children and adolescents.

Soluble transferrin receptor (sTfR) is a marker of both erythropoiesis and iron status and is considered useful for detecting iron deficiency, especially in inflammatory conditions, but reference intervals covering the entire pediatric age spectrum are lacking. We studied 1,064 (48.5 % female) healthy children of the entire pediatric age spectrum to determine reference values and percentiles for sTfR and the ratio of sTfR to log-ferritin (sTfR-F index) using a standard immunoturbidimetric assay. Soluble TfR levels were highly age-specific, with a peak in infancy and a decline in adulthood, whereas the sTfR-F index was a rather constant parameter. There were positive linear relationships for sTfR with hemoglobin (Hb) (p=0.008) and transferrin (females p<0.001; males p=0.003). Anegative association was observed between sTfR and ferritin in females (p<0.0001) and for transferrin saturation and mean corpuscular volume (MCV) in both sexes (both p<0.0001). We found a positive relationship between sTfR and body height, body mass index (BMI) and inflammatory markers (CrP p<0.0001; WBC p=0.0172), while sTfR-F index was not affected by inflammation. Soluble TfR values appear to reflect the activity of infant erythropoiesis and to be modulated by inflammation and iron deficiency even in a healthy cohort.

Lipid levels in a cohort of healthy Danish schoolchildren ages 5 to 17 years

It is internationally recognized to use clinical decision limits (CDL) when interpreting the lipid levels in both adults and children, even though the evidence for children is scarce. The purpose of this study is to describe how lipid levels progress in healthy Danish children ages 5 to 17 years. This study is based on the Childhood Health, Activity, and Motor Performance School Study Denmark (CHAMPS-study DK) consisting of 1456 observations of schoolchildren aged 5 to 17 years. Participants have been tested for blood levels of total cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides, and remnant cholesterol levels are calculated. Finally, sex-specific percentile reference curves are presented. Percentile reference curves stratified by sex were generated for all cholesterols and showed that the total cholesterol level peaks at 4.32 mmol/l in 10-year-old boys and 4.46 mmol/l in nine-year-old girls. HDL levels in boys peak at 1.72 mmol/l in nine-year-old boys. HDL levels in girls and LDL levels in both sexes are nearly constant. Triglycerides kept rising to the age of 17 years in both sexes and remnant cholesterol decreased from age 5 to 17 years in both sexes. BMI z-score adjustment revealed no significant association with total cholesterol in both sexes but a significant association between HDL, LDL, triglycerides, and remnant cholesterol. This study is the first to generate percentile reference curves for blood levels of total cholesterol, LDL, HDL, triglycerides, and remnant cholesterol in a cohort of healthy Danish children aged 5 to 17 years.

Age- and Sex-Dynamic Fluctuations and Reference Intervals for Alkaline Phosphatase Among the Spanish Population.

Interpretation of alkaline phosphatase (ALP) activity is essential for the diagnosis of certain diseases. ALP changes during life and may vary between different populations. To establish reference intervals (RIs) and percentile charts for ALP activity in the Spanish population through a multicentric observational study and to compare the RIs to those defined in other countries. A total of 662 350 ALP measurements from individuals ages 0 to 99 years from 9 Spanish tertiary care centers collected between 2020 and 2022 were analyzed. This study is the largest published in the literature to date. Continuous percentile charts for ALP according to sex and age were established which can be used as RIs. Higher levels are reached during the first weeks of life. In puberty, a differential evolution is observed in both sexes, reaching a peak at 10 to 13 years of age in boys and remaining stable in girls at this age. Significant differences were also observed in adults, higher in men between ages 20 and 49 years and between ages 50 and 79 years in women, as reported in some countries. ALP activity follows an age- and sex-dependent fluctuation with geographic differences. It is important to have appropriate reference values for each population in order to allow for a correct diagnostic interpretation and early diagnosis of diseases related to ALP abnormalities.

Targeting strategies for balanced energy and protein (BEP) supplementation in pregnancy: study protocol for the TARGET-BEP cluster-randomized controlled trial in rural Bangladesh

BackgroundThe World Health Organization (WHO) recommends balanced energy and protein (BEP) supplementation be provided to all pregnant women living in undernourished populations, usually defined as having a prevalence > 20% of underweight women, to reduce the risk of stillbirths and small-for-gestational-age neonates. Few geographies meet this threshold, however, and a large proportion of undernourished women and those with inadequate gestational weight gain could miss benefiting from BEP. This study compares the effectiveness of individual targeting approaches for supplementation with micronutrient-fortified BEP vs. multiple micronutrient supplements (MMS) alone as control in pregnancy in improving birth outcomes.MethodsThe TARGET-BEP study is a four-arm, cluster-randomized controlled trial conducted in rural northwestern Bangladesh. Eligible participants are married women aged 15–35 years old identified early in pregnancy using a community-wide, monthly, urine-test-based pregnancy detection system. Beginning at 12–14 weeks of gestation, women in the study area comprising 240 predefined sectors are randomly assigned to one of four intervention arms, with sector serving as the unit of randomization. The interventions involving daily supplementation through end of pregnancy are as follows: (1) MMS (control); (2) BEP; (3) targeted BEP for those with pre-pregnancy body mass index (BMI) < 18.5 kg/m2 and MMS for others; (4) targeted BEP for those with pre-pregnancy BMI < 18.5 kg/m2, MMS for others, and women with inadequate gestational weight gain switched from MMS to BEP until the end of pregnancy. Primary outcomes include birth weight, low birth weight (< 2500 g), and small for gestational age, defined using the 10th percentile of the INTERGROWTH-21st reference, for live-born infants measured within 72 h of birth. Project-hired local female staff visit pregnant women monthly to deliver the assigned supplements, monitor adherence biweekly, and assess weight regularly during pregnancy. Trained data collectors conduct pregnancy outcome assessment and measure newborn anthropometry in the facility or home depending on the place of birth.DiscussionThis study will assess the effectiveness of targeted balanced energy and protein supplementation to improve birth outcomes among pregnant women in rural Bangladesh and similar settings.Trial registrationClinicalTrials.gov NCT05576207. Registered on October 5th, 2022.

Reference values of skeletal muscle mass for children in Nanjing area

Objective: To establish the reference values and growth curves of skeletal muscle mass among children in the Nanjing area. Methods: A cross-sectional study was conducted with children who underwent physical examination at the Department of Child Health Care, Children's Hospital of Nanjing Medical University from 2020 January to 2022 September. Their height, weight, body fat mass and skeletal muscle mass were measured. Body mass index, percentage of body fat mass, percentage of skeletal muscle mass, relative skeletal muscle mass index and the ratio of skeletal muscle to body fat were calculated. The associations between skeletal muscle mass indices and physical measurements index were analyzed through the Spearman correlation test. The Mann-Kendall test was used to assess the trend for skeletal muscle mass. Generalized additive models for location, scale and shape were used to construct percentile reference values and growth curves of male and female skeletal muscle mass indices at different ages. Results: A total of 32 690 children aged 4-14 years were enrolled in this study, including 19 912 boys (60.91%). Skeletal muscle mass, percentage of skeletal muscle mass, relative skeletal muscle mass index and the ratio of skeletal muscle to body fat of boys and girls was 11.10 (8.40, 14.90) and 10.30 (7.90, 13.20) kg, 40.36% (37.01%, 43.13%) and 39.38% (36.43%, 41.88%), 6.70 (6.07, 7.52) and 6.33 (5.79, 7.00), 2.39 (1.46, 3.47) and 2.14 (1.45, 3.00) kg/m2, respectively. Skeletal muscle mass of both boys and girls was all positively associated with weight (r=0.97, 0.96), body mass index (r=0.68, 0.63) and percentage of body fat mass (r=0.40, 0.43) (all P<0.01). The reference values and growth curves showed that the percentage of skeletal muscle mass P50 ranged from 37.75%-44.61% in boys and from 36.22%-40.55% in girls. The relative skeletal muscle mass index P50 ranged from 5.80-9.68 kg/m2 in boys and from 5.57-7.98 kg/m2 in girls. The ratio of skeletal muscle to body fat P50 ranged from 1.86-2.67 in boys and from 1.29-2.41 in girls. There was an increasing trend with age for both boys and girls in the growth of skeletal muscle mass (Z=4.20, 3.75, both Ptrend<0.01), and increased slightly before 9 years of age and then increased rapidly until 14 years of age in both boys and girls. Conclusions: The skeletal muscle mass indices change with age and gender during childhood. Percentile reference values for pediatric skeletal muscle mass indices can be used to evaluate the muscular growth and development in children in the Nanjing area.

The association between parental cardiovascular health status and the risk of obesity in their offspring: Tehran Lipid and Glucose Study

Background and aimsLittle is known about the association of parental cardiovascular risk factors with the risk of obesity in offspring. We aimed to investigate whether parental ideal cardiovascular health (ICVH) status was associated with the risk of general and central obesity in their young/adult offspring. Methods and resultsOf individuals who participated in the 2012-15 phase of the Tehran Lipid and Glucose Study, 2395 pairs of parent-unmarried offspring aged ≥6 years were selected in this cross-sectional study. General and central obesity were defined based on Iranian BMI percentile reference data for offspring aged ≤18 years. For subjects aged ≥19 years, central obesity was defined based on the introduced cut-off points for Iranian adults. We employed the American Heart Association's 2020 impact goal criteria of ICVH.The mean ± SD age of fathers and mothers were respectively 55.4 ± 9.79 and 48.4 ± 9.88. About 55% of offspring were older than 19 years. Higher adherence to ICVH score in mothers was associated with lower risk of overweight/obesity in female offspring (OR for Q1-Q4: 1, 0.56, 0.57, 0.37, P < 0.05 for all quartiles). Among ICVH components, only ideal BMI status in fathers was observed to be associated with a lower risk of overweight/obesity in their male offspring. The risk of abdominal obesity decreased in female offspring with increasing total ICVH score in mothers. ConclusionHigher adherence of parents to ICVH and its components was positively associated with a lower risk of general and abdominal obesity in their offspring. Our findings demonstrate that maternal-offspring relationship was stronger than paternal-offspring association.

Reference percentiles for mid-upper arm circumference, upper arm muscle and fat areas of Nigerian children and adolescent population aged 0 – 19 years

Reference percentiles for mid-upper arm circumference, upper arm muscle and fat areas of Nigerian children and adolescent population aged 0 – 19 years

Comparison of singleton and twin birth weight reference percentile curves by gestational age and sex in extremely preterm infants: a population-based study

BackgroundWith the increasing survival rate of smaller newborns and twins, previous growth curves may not accurately assess the growth of extremely preterm infants (EPIs). Our study aimed to establish birth...

Population Pharmacokinetics of Cabotegravir Following Oral Administration and Long-Acting Intramuscular Injection in Real-World People with HIV.

Long-acting cabotegravir has been studied mainly in the stringent framework of clinical trials, which does not necessarily reflect the situation of people with HIV (PWH) in routine clinical settings. The present population pharmacokinetic analysis aims to build real-world reference percentile curves of cabotegravir concentrations, accounting for patient-related factors that may affect cabotegravir exposure. The second objective is to simulate whether dosing interval adjustments of cabotegravir could be considered in specific subpopulations. Overall, 238 PWH contributed to 1,038 cabotegravir levels (186 during the initial oral administration phase and 852 after intramuscular injection). Cabotegravir pharmacokinetics was best described using a one-compartment model with distinct first order-absorption for oral and intramuscular administrations, and identical volume and clearance. Our model showed almost 40% faster absorption and 30% higher clearance than previously reported, resulting in a time to steady-state of 8 months and an elimination half-life of 4.6 weeks for long-acting cabotegravir. Sex and body mass index significantly influenced absorption, and bodyweight affected clearance. Model-based simulations showed that cabotegravir trough concentrations in females were 25% lower 4 weeks after the intramuscular loading dose, but 42% higher during the late maintenance phase. Finally, simulations indicated that in females, despite significantly higher cabotegravir concentrations, longer intervals between injections may not consistently ensure levels above the 4-fold protein-adjusted 90% inhibitory target concentration.