Cohort Of School Children Research Articles

Prevalence of Metabolic Syndrome and Its Associated Risk Factors Among Schoolchildren Aged 11-13 Years Living in Thiruvananthapuram District, Kerala, India: A Nested Case-Control Study.

Metabolic syndrome is a cluster of conditions that includes increased blood pressure, increased blood sugar, excess body fat around the waist, and a rise in triglyceride levels which could increase the risk of developing type 2 diabetes and cardiovascular diseases. While metabolic syndrome is typically associated with adults, concern is growing about its prevalence and implications among children and adolescents. The rapid rise in childhood obesity and physical inactivity has led to an increase in risk factors among young populations, making it a pressing public health issue. This study aims to investigate the risk of metabolic syndrome among children aged 11-13 years, exploring its association with various sociodemographic and clinical factors. A nested case-control study was conducted from June 2021 to November 2021 among a cohort ofschool children aged 11-13 years in Thiruvananthapuram district, Kerala, India. Twenty-two clusters (schools) were identified from the schools in Thiruvananthapuram's educational subdistrict using populations proportionate to size. Data on the sociodemographic characteristics and lifestyle practices of 1,580 schoolchildren and their parents were collected using a questionnaire. Body mass index, waist circumference, and blood pressure were also assessed to screen children for metabolic syndrome. Fasting blood glucose, triglycerides, and high‑density lipoprotein levels were evaluated in 57 cases (children with metabolic syndrome after screening) and 116 controls (children without metabolic syndrome after screening). The prevalence of pediatric metabolic syndrome as defined by the International Diabetes Federation (IDF) classification in the sample was 3.6% (n=57) (95%CI 1.6-6.6). Modifiable and nonmodifiable risk factors found to be associated with pediatric metabolic syndrome after multivariate analysis were gender, decreased physical activity, especially organized physical activity and moderately vigorous physical activity or play, skipping meals, sleeping for less than eight hours at night, eating with screens on, use of screens for more than two hours daily, and preference for soft drinks or carbonated drinks over water when thirsty. This studyalso evaluated the predictive power of the associated factors for pediatric metabolic syndrome using receiver operating characteristic (ROC) analysis. The ROC curve showed an area under the curve of 0.926 (95% CI: 0.891-0.961, p < 0.001), indicating high predictive power. The findings of this study brought out evidence of an escalation in the rate of metabolic syndrome among children in their early adolescent stage. This rise is a trend with increasing sedentary time and the overuse of screens by the younger generation in this modern era of gadgets and technologies. Our findings would act as a catalyst in implementing community and school-based activities to improve physical activities and lifestyle modifications among children, thereby reducing the risk of early development of metabolic syndrome.

Association of symptomatic upper respiratory tract infections with the alteration of the oropharyngeal microbiome in a cohort of school children in Côte d'Ivoire.

The oropharyngeal microbiome plays an important role in protection against infectious agents when in balance. Despite use of vaccines and antibiotic therapy to prevent respiratory tract infections, they remain one of the major causes of mortality and morbidity in Low- and middle-income countries. Hence the need to explore other approaches to prevention by identifying microbial biomarkers that could be leveraged to modify the microbiota in order to enhance protection against pathogenic bacteria. The aim of this study was to analyze the oropharyngeal microbiome (OPM) of schoolchildren in Côte d'Ivoire presenting symptoms of upper respiratory tract infections (URTI) for better prevention strategy. Primary schools' children in Korhogo (n = 37) and Abidjan (n = 39) were followed for six months with monthly oropharyngeal sampling. Clinical diagnostic of URT infection was performed and nucleic acid extracted from oropharyngeal swabs were used for 16S rRNA metagenomic analysis and RT-PCR. The clinical examination of children's throat in Abidjan and Korhogo identified respectively 17 (43.59%) and 15 (40.54%) participants with visible symptoms of URTIs, with 26 episodes of infection in Abidjan and 24 in Korhogo. Carriage of Haemophilus influenzae (12%), Streptococcus pneumoniae (6%) and SARS-CoV-2 (6%) was confirmed by PCR. A significant difference in alpha diversity was found between children colonized by S. pneumoniae and those that were not (p = 0.022). There was also a significant difference in alpha diversity between children colonised with H. influenzae and those who were not (p = 0.017). No significant difference was found for SARS-CoV-2. Sphingomonas, Ralstonia and Rothia were significantly enriched in non-carriers of S. pneumoniae; Actinobacillus was significantly enriched in non-carriers of H. influenzae; Actinobacillus and Porphyromonas were significantly enriched in non-carriers of SARS-CoV-2 (p < 0.001). Nearly 40% of children showed clinical symptoms of infection not related to geographical location. The OPM showed an imbalance during H. influenzae and S. pneumoniae carriage. This study provides a baseline understanding of microbiome markers in URTIs in children for future research, to develop targeted interventions aimed at restoring the microbial balance and reducing the symptoms associated with RTIs.

Vitamin D status and leukocyte telomere length in middle childhood.

Short telomere length is associated with chronic diseases and decreased lifespan. Vitamin D and its binding protein (DBP) may maintain telomeres through anti-inflammatory actions, yet the role of vitamin D on telomere length is uncertain, especially in children. We assessed the cross-sectional associations of plasma 25-hydroxy vitamin D (25(OH)D) and DBP with leukocyte telomere length (LTL) in a group of 447 children ages 5-12 years from the Bogotá School Children Cohort. We compared the distribution of age-standardized LTL (z-score) between 25(OH)D categories and between DBP quartiles overall and by sex. Overall, 25(OH)D was not significantly associated with LTL. Nonetheless, among boys, 25(OH)D < 50 nmol/L was related to an adjusted 0.36 shorter LTL z-score (95% CI: -0.71, -0.01; P = 0.046) compared with 25(OH)D ≥ 75 nmol/L. There was no association among girls. DBP was not significantly related to LTL. Intervention studies are warranted to determine whether increasing vitamin D status enhances telomere length.

Prerequisites for the introduction of climbing in the recreational activities of primary school age children with emotional and volitional disorders

The article aims to determine the advisability and prerequisites for the introduction of climbing in the recreational activities of primary school age children with emotional and volitional disorders. The following research methods were used: theoretical analysis of professional scientific and methodological literature; comparative analysis; expert assessment; pedagogical, anthropometric, physiological, psychodiagnostic research methods; physical health assessment methods; mathematical statistics methods.&#x0D; Based on the expert assessment, we identified factors limiting the effectiveness of health and recreational activities with this cohort, and determined the organizational and methodological conditions for the introduction of climbing in recreational activities of primary school age children with emotional and volitional disorders. The analysis of the physical development of children with emotional and volitional disorders confirmed and supplemented research conducted by other authors proving that emotional and volitional disorders do not have any fundamental influence on changes in the growth patterns of the child's body. It was found that the indicators of the functional state of the cardiovascular system of primary school children with emotional and volitional disorders did not differ significantly from that of children of the same age with normative development.&#x0D; The analysis of the physical fitness of the studied cohort confirmed the existing trends in the professional literature regarding the insufficient level of physical qualities development in junior schoolchildren. The results obtained in 6 motor tests measuring the development of coordination skills indicate that in younger students aged 9-10 the level of these skills is much lower than in their peers with normative development. The analysis of the emotional and volitional features of junior schoolchildren aged 9-10 years of both sex groups showed the lack or insufficient development of the following studied qualities: discipline, independence, perseverance, endurance, organization, determination, and initiative, which indicates the difference between this cohort of students from their peers with normative development. In the study of the psycho-emotional sphere in this cohort of schoolchildren, we found dominance of medium and high levels of psycho-emotional stress in both boys and girls aged 9-10, which significantly distinguishes them from peers with normative development.

Russian Schools during the COVID-19 Pandemic: Impact of the First Two Waves on the Quality of Education

International studies about the impact of the COVID-19 pandemic on the quality of general education have yielded contradictory results: educational outcomes have fallen markedly in some countries while remaining more or less constant in others. At the same time, over half of published studies attest to the growth of educational inequality during the pandemic. The present article assesses the impact of the pandemic using the data of a regional monitoring study of all schoolchildren in grades 4, 6 and 8 in the Krasnoyarsk Region in 2019 and 2021. Tests of reading literacy in grades 4 and 6 as well as of science literacy in grade 8 have shown the satisfactory psychometric quality. Multilevel regression analysis was used to show that the level of functional literacy of the “pandemic” cohort of schoolchildren, controlled for contextual characteristics, was significantly lower for students in all grades except grade 4. The biggest loss was found for scientific literacy. No correlation was found between the pandemic effect size and the socioeconomic composition of the class (the gap between children with different SES remains at the same level as it was before the pandemic). The teachers’ opportunity to conduct online classes did not serve to improve the educational outcomes of schoolchildren during the pandemic.

The Impact of COVID-19 on Sport and Daily Activities in an Italian Cohort of Football School Children

Background: Sport activities were interrupted due to a quarantine imposed to limit the spread of Coronavirus disease 2019 (COVID-19) in Italy. This study aimed to describe the impact of COVID-19 on sports and on daily activities in an Italian cohort of school children signed up in a football school. Methods: A total of 44 children from an Italian football school were enrolled. An online survey was distributed to these children and their parents in May 2020. The questionnaire collected information on the daily use of electronic devices and on the number of hours per week spent in activities regarding nonsport activities, highlighting the differences between those who interrupted sports and those who continued driven remotely by their instructors during the lockdown. Results: A total of 26 players continued practicing sports during the COVID-19 quarantine, while 18 players suspended their sports. Daily time spent on electronic devices increased significantly in both groups during the pandemic (p &lt; .0001), regardless of whether they continued to practice sports (p &gt; .05). On the other hand, in the group of children who interrupted sports, the time spent on activities regarding nonsport physical activity significantly changed during pandemic, with a 50% decrease (p = .0027) of those who spent more than 3 hr per week before the quarantine in favor of those who spent less than 3 hr per week. Conclusion: Quarantine increases screen time, which is a sedentary behavior that represents a risk factor for the health of children. Maintaining regular physical activity during quarantine due to COVID-19 was important to preserve some aspects of a healthy lifestyle in children, such as physical activity regardless of sport. While reducing physical activity and adapting it remotely, it is desirable that it be encouraged by experienced instructors in order to limit potential physical and psychological harm to children.

Asthma clustering methods: a literature-informed application to the children’s health study data

Objective The heterogeneity of asthma has inspired widespread application of statistical clustering algorithms to a variety of datasets for identification of potentially clinically meaningful phenotypes. There has not been a standardized data analysis approach for asthma clustering, which can affect reproducibility and clinical translation of results. Our objective was to identify common and effective data analysis practices in the asthma clustering literature and apply them to data from a Southern California population-based cohort of schoolchildren with asthma. Methods As of January 1, 2020, we reviewed key statistical elements of 77 asthma clustering studies. Guided by the literature, we used 12 input variables and three clustering methods (hierarchical clustering, k-medoids, and latent class analysis) to identify clusters in 598 schoolchildren with asthma from the Southern California Children’s Health Study (CHS). Results Clusters of children identified by latent class analysis were characterized by exhaled nitric oxide, FEV1/FVC, FEV1 percent predicted, asthma control and allergy score; and were predictive of control at two year follow up. Clusters from the other two methods were less clinically remarkable, primarily differentiated by sex and race/ethnicity and less predictive of asthma control over time. Conclusion Upon review of the asthma phenotyping literature, common approaches of data clustering emerged. When applying these elements to the Children’s Health Study data, latent class analysis clusters—represented by exhaled nitric oxide and spirometry measures—had clinical relevance over time.

Age-specific social mixing of school-aged children in a US setting using proximity detecting sensors and contact surveys

Comparisons of the utility and accuracy of methods for measuring social interactions relevant to disease transmission are rare. To increase the evidence base supporting specific methods to measure social interaction, we compared data from self-reported contact surveys and wearable proximity sensors from a cohort of schoolchildren in the Pittsburgh metropolitan area. Although the number and type of contacts recorded by each participant differed between the two methods, we found good correspondence between the two methods in aggregate measures of age-specific interactions. Fewer, but longer, contacts were reported in surveys, relative to the generally short proximal interactions captured by wearable sensors. When adjusted for expectations of proportionate mixing, though, the two methods produced highly similar, assortative age-mixing matrices. These aggregate mixing matrices, when used in simulation, resulted in similar estimates of risk of infection by age. While proximity sensors and survey methods may not be interchangeable for capturing individual contacts, they can generate highly correlated data on age-specific mixing patterns relevant to the dynamics of respiratory virus transmission.

Wearing face mask during physical exercise

Wearing face mask during physical exercise

Decrease of external skeletal robustness (Frame Index) between two cohorts of school children living in Puerto Madryn, Argentina at the beginning of the 21st century.

Background: It has been shown that modern life style with reduced physical activity can lead to lower bone accumulation. Also a decline trend in external skeletal robustness in children and young adolescents, measured by the Frame Index (FI), seems to have a parallel trend with the increase in overweight and obesity. Based on these findings we estimate that likely, the FI should be changed after a decade in the Argentinean population as well as in others population of the world. Thereby, the aim of the present study was to describe, using the FI, the pattern of external skeletal robustness in school children aged 6-14 years from two cohorts of Argentina (Puerto Madryn, Chubut) and to compare them with the European reference (Czech Republic, Germany, Poland and Russia). Methods: Elbow breadth and height of Puerto Madryn school children were collected in two cross-sectional studies conducted between 2001-2006 (cohort 1 = C1) and 2014-2016 (cohort 2 = C2). Percentiles (P) values, for males and females, from C1 and C2 were calculated combining the LMS-method and its extension. A t-test has been used to compare, by age and sex, the FI values between the Argentinean cohorts and the European reference (ER). Then, in order to know the percentage of the variation of the percentiles values between cohorts, as well as with ER, percent differences between means (PDM%) were employed. Results: FI from Argentinean cohorts differed significantly from ER. Even more, C2 was not only smaller than ER, but also than C1. In males, C1-C2 showed significant differences at 6-8, 11 and 12 years and in females at all ages. Then, respect to ER each Argentinean cohort showed significant differences in males of C1 at 6, 12-14 years and in females at 6 and 11-14 years; and of C2, in both sexes, from 6 to 14 years. The PDM% values for elbow breadth of male were negative in ER-C1 in all percentiles analyzed; in ER-C2 positive (P3 and P50) and negative (P97) and C1-C2 recorded positive values. In females, elbow breadth showed negative values for ER-C1 (P50 and P97), and positive for the remaining values. Finally, height registered, in both sexes, negative values in ER-C1 (except P97 in females), ER-C2 and C1-C2. Conclusions: After ten years of the first study carried on in Puerto Madryn, school children show a negative trend in the external skeletal robustness. Additionally, the children of both Argentinean cohorts have lower values compared to the European reference, and mainly the actual cohort. This situation would be explained, in part, by the progressive increase over time of overweight and obesity as consequence, among others, of the change in the quantity and/or quality of the food that children have access to and with the physical activity they do at school and outside.

Six rounds of annual praziquantel treatment during a national helminth control program significantly reduced schistosome infection and morbidity levels in a cohort of schoolchildren in Zimbabwe.

BackgroundThe World Health Organization recommends that schistosomiasis be treated through Mass Drug Administration (MDA). In line with this recommendation, Zimbabwe commenced a national helminth control program in 2012 targeting schoolchildren throughout the country for 6 years. This study, part of a larger investigation of the impact of helminth treatment on the overall health of the children, determined the effect of annual praziquantel treatment on schistosome infection and morbidity in a cohort of children during Zimbabwe’s 6-year national helminth control program.Methodology/Principal findingsA school-based longitudinal study was carried out in 35 sentinel sites across Zimbabwe from September 2012 to November 2017. The sentinel sites were selected following a countrywide survey conducted in 280 primary schools. Schistosoma haematobium was diagnosed using the urine filtration technique. Schistosoma mansoni was diagnosed using both the Kato-Katz and formol-ether concentration techniques. S. haematobium morbidity was determined through detection of macro and microhaematuria. A cohort of children aged 6–15 years old was surveyed annually before MDA and 6 weeks post treatment. Maximum treatment coverage reached 90% over the 6 rounds of MDA. At baseline S. haematobium infection prevalence and intensity were 31.7% (95% CI = 31.1–32.2) and 28.75 eggs/10ml urine (SEM = 0.81) respectively, while S. mansoni prevalence and intensity were 4.6% (95% CI = 4.4–4.8) and 0.28 eggs/25mg (SEM = 0.02). Prior to the 6th round of MDA, S. haematobium infection prevalence had reduced to 1.56% (p<0.001) and infection intensity to 0.07 (SEM 0.02). Six weeks later after the 6th MDA, both were 0. Similarly the prevalence of S. haematobium morbidity as indicated by haematuria also fell significantly from 32.3% (95% CI = 29.9–34.6) to 0% (p< 0.0001) prior to the final MDA. For S.mansoni, both prevalence and intensity had decreased to 0 prior to the 6th MDA. After 6 rounds of annual MDA, prevalence and intensity of both schistosome species decreased significantly to 0% (p< 0.0001).ConclusionZimbabwe’s helminth control program significantly reduced schistosome infection intensity and prevalence and urogenital schistosomiasis morbidity prevalence in a cohort of school-aged children, moving the schistosome prevalence in the children from moderate to low by WHO classification. These findings will inform the design of the country’s next stage interventions for helminth control and eventual elimination.

The association between ambient NO2 and PM2.5 with the respiratory health of school children residing in informal settlements: A prospective cohort study

BackgroundNo previous epidemiological study has investigated the combined association of long-term ambient nitrogen dioxide (NO2) and particulate matter of diameter size-2.5 (PM2.5) exposure with asthma outcomes among schoolchildren in Africa. ObjectivesThis study investigated the independent and co-pollutant association of long-term exposures to ambient air pollutants on asthma-associated outcomes in a cohort of schoolchildren in the Western Cape Province of South Africa. MethodsA total of 590 grade-4 schoolchildren residing in four informal settlements were studied. Spirometry and fractional exhaled nitric-oxide (FeNO) measurements were conducted, including a standardized questionnaire administered to caregivers at baseline and 12-months follow-up. Annual NO2 and PM2.5 levels were estimated for each child's home using land-use regression modelling. Single- and two-pollutant models were constructed to assess the independent and co-pollutant association of both air pollutants (NO2 and PM2.5) on new cases of asthma-associated outcomes adjusting-for host characteristics, indoor exposures and study area. ResultsThe annual average concentration of PM2.5 and NO2 were 10.01μg/m3 and 16.62μg/m3 respectively, across the four study areas, and were below the local Standards of 20μg/m3 and 40μg/m3, for both pollutants, respectively. In the two-pollutant-adjusted models, an interquartile range (IQR) increase of 14.2μg/m3 in NO2 was associated with an increased risk of new onset of ocular-nasal symptoms (adjusted odds ratio–aOR: 1.63, 95% CI: 1.01–2.60), wheezing (aOR: 3.57, 95% CI: 1.18–10.92), more than two or more asthma symptom score (aOR: 1.71, 95% CI: 1.02–2.86), and airway inflammation defined as FeNO > 35 ppb (aOR: 3.10, 95% CI: 1.10–8.71), independent of PM2.5 exposures. ConclusionThis study provided evidence that ambient NO2 levels below local standards and international guidelines, independent of PM2.5 exposure, increases new cases of asthma-associated outcomes after 12-months.

Perinatal antecedents of sleep disturbances in schoolchildren.

Prematurity has been associated with an increased risk for sleep apnea. However, sleep disturbances in children born preterm have not been extensively investigated. Considering that determinants of sleep may originate early in life, the potential impact of prematurity on sleep disturbances later in life could be important. To establish the role of prematurity on sleep disturbances in a cohort of schoolchildren that were born preterm and compare them with healthy controls. A cohort of 147 schoolchildren, 45 born at term (≥37 weeks) and 102 very preterm (<32 weeks), was recruited and evaluated at school age (5-9 years). The Pediatric Sleep Questionnaire (PSQ) and the Sleep Disturbance Scale for Children (SDSC) were used to assess sleep disturbances in different domains. PSQ score was significantly higher in former preterm children (0.26 ± 0.18 vs. 0.18 ± 0.14 in controls; p = 0.004), and SDSC total score was also significantly different among groups (21.7 ± 11.6 vs. 14.1 ± 12.6; p < 0.001). Regression models showed significant mean differences in PSQ score, total SDSC score, and two SDSC subscale scores (i.e. sleep-wake transition disorders, sleep-breathing disorders, and sleep hyperhidrosis) even after adjustment for confounders. Maternal age and type of delivery were not significantly associated with total PSQ scores. Sleep disturbances may originate early in life since children born preterm exhibit an increased risk for developing long-term sleep problems. These findings may have important implications for management of preterm children and for implementation of early interventions focused on optimizing sleep habits.

Incidence Study of Epilepsy using the ILAE 2017 Classification of Epilepsies in a Cohort of School Children Accessing Education in Government Primary Schools in South India.

Recently, the International League Against Epilepsy (ILAE) has proposed new classification schemes for seizures and epilepsy. The applicability of these classification schemes has not been studied in resource-poor countries. To determine the incidences of epilepsies in a cohort of school children using the ILAE 2017 classification of epilepsies. The study cohort included 7,408 school going children [age range 5-15 years]. They were followed for new-onset unprovoked seizure and seizure recurrence through first grade to fifth grade. The data collected during the first visit included clinical details including details of seizure semiology. All children had EEG and contrast CT scan. All these data were used to classify seizure type and epilepsy using ILAE classification schemes. The ILAE 2014 epilepsy definition was used to diagnose epilepsy. The average annual incidence rates (AAIR) and 95% confidence intervals (CI) were calculated for epilepsies by onset and by etiology. The AAIR of epilepsy was 57.85 (95% CI 39.0-82.6) per 100,000 population. The AAIRs per 100,000 for different epilepsies by mode of onset were focal epilepsies 25.07 (95% CI 13.35-42.87); generalized epilepsies 13.5 (95% CI 5.43-27.8); and unknown onset epilepsies 19.28 (95% CI 9.25-35.46). The AAIRs per 100,000 of epilepsies by etiology were focal genetic epilepsies 7.71 (95% CI 2.1-19.75); genetic generalized epilepsies 13.5 (95% CI 5.43-27.8); and epilepsies due to structural cause 17.36 (95% CI 9.25-35.46). The lesional epilepsies seen in this cohort were geographically specific to resource-poor countries. The AAIR of epilepsy due to calcific neurocysticercosis (cNCC) was 9.64 (95% CI 3.1-22.5) per 100,000. This study demonstrates that the ILAE 2017 classification of epilepsies can be applied in resource-poor countries with limited workup. Lesional epilepsies seen in this study is geographically specific to resource-poor countries.

The effects of ambient NO2 and PM2.5 exposure on asthma-related outcomes in school children residing in informal settlements in South Africa.

OPS 52: Air pollution and respiratory health, Room 110, Floor 1, August 28, 2019, 10:30 AM - 12:00 PM Background/Aim: No previous epidemiological study has investigated the independent effect of long-term ambient nitrogen dioxide (NO2) and particulate matter smaller than 2.5 µm in diameter (PM2.5) exposure on asthma-related outcomes among school children in Africa. This study aimed to investigate these effects in a cohort of school children in the Western Cape Province of South Africa. Methods: Grade-4 school children (n = 522) residing in four informal settlements were followed for a 12-months period. Spirometry and fractional exhaled nitric-oxide (FeNO) measurements were conducted on each child in addition to the International Study on Asthma and Allergy in Children (ISAAC) questionnaire that was administered to the parent/caregiver at baseline and follow-up. Annual NO2 and PM2.5 levels were estimated for each child’s home using land-use regression modelling. Two-pollutant models were constructed to assess the independent effects of both ambient NO2 and PM2.5 on incident asthma-associated outcomes adjusting-for host characteristics, indoor exposures and residential area. Results: The annual average concentration of PM2.5 and NO2 in the four study areas (10.01 μg/m3 and 16.62 µg/m3 respectively), were below the South Africa National Ambient Air Quality Standards (20 μg/m3 and 40 µg/m3, respectively) for both pollutants. An interquartile range (IQR) increase of 14.2 µg/m3 in NO2 was associated with an increased risk of new onset ocular-nasal symptoms (adjusted odds ratio [aOR]: 1.63, 95% Confidence Interval [CI]: 1.01 – 2.60), wheezing (aOR: 3.57, 95% CI: 1.18 – 10.92), symptom score ≥2 (aOR: 1.71, 95% CI: 1.02 – 2.86), and allergic airway inflammation defined as FeNO > 35 ppb (aOR: 3.10, 95% CI: 1.10 – 8.71), independent of PM2.5 exposures. Conclusion: This study provides evidence of an effect of ambient NO2 below national and international guidelines, independent of PM2.5 exposure, on 12-months incidence of asthma-related outcomes among children residing in informal settlements of South Africa.

P3134Variations in anterior mitral valve leaflet restriction that may lead to the erroneous diagnosis of rheumatic heart disease

Abstract Introduction Anterior mitral valve leaflet (AMVL) restriction is a prominent morphological feature of rheumatic heart disease (RHD). The World Heart Federation (WHF) criteria for echocardiographic diagnosis of RHD rely on the use of colloquial terms such as “dog-leg” to define AMVL restriction rather than a strict, reproducible definition. We recognise AMVL restriction when the tip of the leaflet is seen to point away from the interventricular septum and towards the posterior left ventricular (LV) wall at peak diastole in the parasternal long axis (PSLAX) view. This definition however risks inclusion of a finding commonly identified in our high-risk screening program (Echo in Africa- EIA) which demonstrates gradual AMVL bowing (so-called “slow-bow”) from the proximal to mid-leaflet but with free motion ('fluttering') of the tip during diastole. This is in contrast to RHD-related restriction which typically involves the distal AMVL tip only. We propose that the former is a normal variant of the AMVL and is unrelated to the RHD process, provided no concomitant morphological features of RHD are identified. Purpose Determine the prevalence of “slow-bow” AMVL restriction between two cohorts of schoolchildren with a documented high-and low-RHD prevalence. Methods Retrospective analysis of EIA data obtained from children (aged 13–18) attending two separate South African schools. The high-RHD prevalence school (HR) demonstrated a 0.8% rate of WHF “definite RHD”. The low-RHD prevalence school (LR) demonstrated no cases of WHF “definite RHD”. Cases of AMVL restriction were identified and classified according to the definitions provided above. Results A total of 941 screening studies (HR cohort n=577 /LR cohort n=364) were evaluated. 74 cases of AMVL restriction (12.82%, 95%, CI 10.34–15.80) were identified in the HR cohort of which 8 cases demonstrated AMVL-tip restriction (1.39%, 95%, CI 0.70–2.71) and 65 cases demonstrated “slow bow” (11.27%, 95%, CI 8.94–14.11). There were no cases of AMVL-tip restriction observed in the LR-cohort and 35 cases of “slow-bow”(9.62%, 95%, CI 7–13.08). A. “Slow bow”; B. “Distal tip restriction”. Conclusion Our results support the hypothesis that “slow-bow” AMVL restriction is a common variant of the AMVL amongst South African school children and unrelated to the RHD process. Further research is required to investigate the exact mechanism underlying this form of AMVL restriction. Acknowledgement/Funding Edwards Lifescience EHM grant

Epidemiology of dengue and other arboviruses in a cohort of school children and their families in Yucatan, Mexico: Baseline and first year follow-up.

Dengue is the most prevalent mosquito-borne viral disease of humans and is caused by the four serotypes of dengue virus. To estimate the incidence of dengue and other arboviruses, we analyzed the baseline and first year follow-up of a prospective school-based cohort study and their families in three cities in the state of Yucatan, Mexico. Through enhanced surveillance activities, acute febrile illnesses in the participants were detected and yearly blood samples were collected to evaluate dengue infection incidence. A Cox model was fitted to identify hazard ratios of arboviral infections in the first year of follow-up of the cohort. The incidence of dengue symptomatic infections observed during the first year of follow-up (2015–2016) was 3.5 cases per 1,000 person-years (95% CI: 1.9, 5.9). The incidence of dengue infections was 33.9 infections per 1,000 person-years (95% CI: 31.7, 48.0). The majority of dengue infections and seroconversions were observed in the younger age groups (≤ 14 years old). Other arboviruses were circulating in the state of Yucatan during the study period. The incidence of symptomatic chikungunya infections was 8.6 per 1,000 person-years (95% CI: 5.8, 12.3) and the incidence of symptomatic Zika infections was 2.3 per 1,000 person-years (95% CI: 0.9, 4.5). Our model shows that having a dengue infection during the first year of follow-up was significantly associated with being female, living in Ticul or Progreso, and being dengue naïve at baseline. Age was not significantly associated with the outcome, it was confounded by prior immunity to dengue that increases with age. This is the first report of a cohort in Latin America that provides incidence estimates of the three arboviruses co-circulating in all age groups. This study provides important information for understanding the epidemiology of dengue and other arboviruses and better informing public health policies.

Dengue seroprevalence in a cohort of schoolchildren and their siblings in Yucatan, Mexico (2015-2016).

BackgroundThe implementation of vector control interventions and potential introduction new tools requires baseline data to evaluate their direct and indirect effects. The objective of the study is to present the seroprevalence of dengue infection in a cohort of children 0 to 15 years old followed during 2015 to 2016, the risk factors and the role of enhanced surveillance strategies in three urban sites (Merida, Ticul and Progreso) in Yucatan, Mexico.MethodsA cohort of school children and their family members was randomly selected in three urban areas with different demographic, social conditions and levels of transmission. We included results from 1,844 children aged 0 to 15 years. Serum samples were tested for IgG, NS1 and IgM. Enhanced surveillance strategies were established in schools (absenteeism) and cohort families (toll-free number).ResultsSeroprevalence in children 0 to 15 years old was 46.8 (CI 95% 44.1–49.6) with no difference by sex except in Ticul. Prevalence increased with age and was significantly lower in 0 to 5 years old (26.9%, 95% CI:18.4–35.4) compared with 6 to 8 years old (43.9%, 95% CI:40.1–47.7) and 9 to 15 years old (61.4%, 95% CI:58.0–64.8). Sharing the domestic space with other families increased the risk 1.7 times over the individual families that own or rented their house, while risk was significantly higher when kitchen and bathroom were outside. Complete protection with screens in doors and windows decreased risk of infection. Seroprevalence was significantly higher in the medium and high risk areas.ConclusionsThe prevalence of antibodies in children 0 to 15 years in three urban settings in the state of Yucatan describe the high exposure and the heterogenous transmission of dengue virus by risk areas and between schools in the study sites. The enhanced surveillance strategy was useful to improve detection of dengue cases with the coincident transmission of chikungunya and Zika viruses.

Clinical and Epidemiologic Patterns of Chikungunya Virus Infection and Coincident Arboviral Disease in a School Cohort in Haiti, 2014-2015.

BackgroundBeginning in December 2013, an epidemic of chikungunya virus (CHIKV) infection spread across the Caribbean and into virtually all countries in the Western hemisphere, with >2.4 million cases reported through the end of 2017.MethodsWe monitored a cohort of school children in rural Haiti from May 2014, through February 2015, for occurrence of acute undifferentiated febrile illness, with clinical and laboratory data available for 252 illness episodes.ResultsOur findings document passage of the major CHIKV epidemic between May and July 2014, with 82 laboratory-confirmed cases. Subsequent peaks of febrile illness were found to incorporate smaller outbreaks of dengue virus serotypes 1 and 4 and Zika virus, with identification of additional infections with Mayaro virus, enterovirus D68, and coronavirus NL63. CHIKV and dengue virus serotype 1 infections were more common in older children, with a complaint of arthralgia serving as a significant predictor for infection with CHIKV (odds ratio, 16.2; 95% confidence interval, 8.0–34.4; positive predictive value, 66%; negative predictive value, 80%).ConclusionsViral/arboviral infections were characterized by a pattern of recurrent outbreaks and case clusters, with the CHIKV epidemic representing just one of several arboviral agents moving through the population. Although clinical presentations of these agents are similar, arthralgias are highly suggestive of CHIKV infection.

Iron Deficiency, Anemia, and Low Vitamin B-12 Serostatus in Middle Childhood Are Associated with Behavior Problems in Adolescent Boys: Results from the Bogotá School Children Cohort

Iron deficiency (ID) in infancy is related to subsequent behavior problems. The effects of micronutrient status in middle childhood are uncertain. The aim of the study was to examine the associations of micronutrient status biomarkers in middle childhood with externalizing and internalizing behavior problems in adolescence. We assessed whether ID (ferritin <15 µg/L), anemia (hemoglobin <12.7 g/dL), or blood concentrations of zinc, vitamins A and B-12, and folate at ages 5-12 y were associated with externalizing or internalizing behavior problems in adolescence in 1042 schoolchildren from Bogotá, Colombia. Behavior problems were assessed with the Youth Self-Report questionnaire after a median 6.2 y of follow-up. Mean problem score differences with 95% CIs were estimated between categories of micronutrient status biomarkers with the use of multivariable linear regression. Mean±SD externalizing and internalizing problems scores were 52.6±9.6 and 53.8±9.9, respectively. Among boys, middle-childhood ID, anemia, and low plasma vitamin B-12 were associated with 5.9 (95% CI: 1.0, 10.7), 6.6 (95% CI: 1.9, 11.3), and 2.7 (95% CI: 0.4, 4.9) units higher mean externalizing problems scores in adolescence, respectively-after adjustment for baseline age, time spent watching television or playing video games, mother's height, and socioeconomic status. Also in boys, ID was related to an adjusted 6.4 (95% CI: 1.2, 11.6) units higher mean internalizing problems score. There were no associations among girls. Other micronutrient status biomarkers were not associated with behavior problems. ID, anemia, and low vitamin B-12 in middle childhood are related to behavior problems in adolescent boys.This study was registered at clinicaltrials.gov as NCT03297970.