Index Percentile Research Articles

Predictors and moderators of outcomes and readmission for adolescent inpatients with anorexia nervosa: A pilot study

ObjectiveThis pilot study investigated predictors, moderators, and mediators of outcome and readmission in adolescents receiving specialist inpatient treatment for anorexia nervosa.MethodAdolescents (n = 40) aged between 14 and 17 years (mean = 15.42) were assessed at admission and discharge from a specialist inpatient programme and again at three‐month follow‐up on the following outcome variables: eating disorder pathology, quality of life (QOL), and body mass index (BMI) centile. Readmissions to hospital were recorded over the three months post‐discharge period. Potential predictors were drawn from theoretical models.ResultsReadmission during the three‐month follow‐up period was less likely for first presentations. Higher baseline purging, concern over mistakes, perfectionism, ineffectiveness, and mood intolerance were associated with higher levels of eating disorder pathology and poorer QOL over all points of follow‐up. Driven exercise moderated weight outcomes such that higher levels of baseline exercise resulted in a lower BMI centile at follow‐up. Greater weight gain during treatment predicted higher BMI centile at follow‐up, and increased perfectionism during treatment predicted a greater likelihood of being readmitted within three months of discharge.ConclusionsWeight gain during inpatient treatment should be encouraged to improve later weight outcomes. Focusing on the prevention of growth in perfectionism may be useful in improving psychological outcomes as will prioritising the elimination of purging and improved emotional regulation and self‐efficacy. Efforts should be made to reduce driven exercise to promote better weight‐related outcomes.

Assessment of Vulnerability to Coccidioidomycosis in Arizona and California.

Coccidioidomycosis is a fungal infection endemic to the southwestern United States, particularly Arizona and California. Its incidence has increased, potentially due in part to the effects of changing climatic variables on fungal growth and spore dissemination. This study aims to quantify the county-level vulnerability to coccidioidomycosis in Arizona and California and to assess the relationships between population vulnerability and climate variability. The variables representing exposure, sensitivity, and adaptive capacity were combined to calculate county level vulnerability indices. Three methods were used: (1) principal components analysis; (2) quartile weighting; and (3) percentile weighting. Two sets of indices, “unsupervised” and “supervised”, were created. Each index was correlated with coccidioidomycosis incidence data from 2000–2014. The supervised percentile index had the highest correlation; it was then correlated with variability measures for temperature, precipitation, and drought. The supervised percentile index was significantly correlated (p < 0.05) with coccidioidomycosis incidence in both states. Moderate, positive significant associations (p < 0.05) were found between index scores and climate variability when both states were concurrently analyzed and when California was analyzed separately. This research adds to the body of knowledge that could be used to target interventions to vulnerable counties and provides support for the hypothesis that population vulnerability to coccidioidomycosis is associated with climate variability.

Assessing the impact of adjusting for maturity in weight status classification in a cross-sectional sample of UK children

ObjectivesTo compare the weight categorisation of a cohort of UK children using standard procedures (ie, comparing body mass index (BMI) centiles to age-matched UK reference data) versus an approach adjusted...

Abstract P135: Abdominal Obesity is Associated With DNA Methylation in Cardiovascular Health Related Genes Among Adolescents

Background: Obesity, especially abdominal obesity, is a risk factor for coronary artery disease (CAD) in various populations. Little is known regarding the role of epigenetics in the association between abdominal obesity and cardiovascular health in adolescents. Hypothesis: Abdominal and especially visceral obesity is associated with DNA methylation in genes related to cardiovascular health among adolescents. Methods: We used data from a sample of 263 adolescents participating in the population-based Penn State Child Cohort follow-up exam (N=421). Dual-energy X-ray absorptiometry was used to measure visceral and subcutaneous fat areas (VAT; SAT, in cm 2 ) in each participant. We extracted DNA from peripheral leukocytes and subjected it to enhanced, reduced representation bisulfite sequencing. A high-throughput assay provided single nucleotide resolution of DNA methylation in cytosine-phosphate-guanine (CpG) sites and surrounding regions. We excluded bases with &lt; 10x coverage or available from &lt; 20 individuals. We analyzed a total of 1,609,424 methylation sites. We used linear regression models to assess the association between site-specific methylation level (expressed as %) and VAT and SAT. We adjusted all models for age, race, sex, and body mass index (BMI) percentile. We used Bonferroni-adjusted statistical tests to identify sites significantly related to VAT and separately, SAT. We mapped the VAT- and SAT-associated sites to the hg19 assembly and subjected them to Ingenuity Pathway Analysis (IPA) wherein mapped gene sets were examined for enrichment of downstream function and diseases. Results: On average, the sample was 55% male, 79% white and aged 16.7 (standard deviation = 2.2) years. VAT and SAT were significantly associated with methylation at 296 sites within 193 genes and 101 sites within 87 genes, respectively. Among them, seven genes related to VAT and five related to SAT were associated with CAD. IPA revealed that CAD-related genes were significantly enriched in both gene sets (for VAT: p=1.97x10 -2 ; SAT: p=9.67x10 -3 ). Genes related to VAT also were significantly enriched in endothelial activation (p=8.16x10 -3 ), fibrogenesis (p=5.01x10 -5 ), and dyslipidemia (p=7.99x10 -3 ). Indeed, higher VAT was associated with hypomethylation of CD14 and hypermethylation of GNMT , while higher SAT was associated with hypermethylation of ADRB1 and hypomethylation of TUBB4A . Conclusion: If externally validated, our data would suggest that (1) abdominal obesity in adolescence is associated with DNA methylation of genes related to cardiovascular health, independent of BMI; and (2) visceral adiposity has a more prominent association with cardiovascular health through DNA methylation of genes with roles in atherogenesis.

The influence of elevation, latitude and Arctic Oscillation on trends in temperature extremes over northeastern China, 1961–2011

Trend magnitudes of 14 indices of temperature extremes at 70 stations with elevations, latitude and Arctic Oscillation over northeast China during 1960–2011 are examined. There are no significant correlations between elevation and trend magnitudes with the exception of TXn (Min Tmax), TNn (Min Tmin), TR20 (tropical nights) and GSL (growing season length). Analysis of trend magnitudes by topographic type has a strong influence, which overrides that of degree of urbanization. By contrast, most of the temperature indices have stronger correlations with the latitude and Arctic Oscillation index. The correlations between the Arctic Oscillation index and percentile indices, including TX10p (cool days), TX90p (warm days), TN10p (cool nights), TN90p (warm nights), are not the same in different areas. To summarize, analysis of trend magnitudes by topographic type, the latitude and the Arctic Oscillation shows three factors to have a strong influence in this dataset, which overrides that of elevation and degree of urbanization.

Weight Management Behaviors Among Mexican American Youth: Cross-Sectional Variation by Timing of Growth and Maturation.

To assess the association between growth and maturation with weight management behaviors (WMBs) among Mexican American youth. A cross-sectional design was used to measure timing of growth and maturation as well as WMBs. Students were recruited through physical education classes in south Texas schools. The sample included 623 participants (52.3% female; 49.8% with weight ≥85th percentile) in grades 4 through 12. Students in middle school were purposely oversampled to examine questions around timing of growth and maturation. Growth was measured as maturity offset, an estimate of age at peak height velocity (PHV). Maturity offset is derived from chronological age, height, and sitting height measurements. Participants were classified as pre-PHV or post-PHV. Girls also were categorized as premenarche or early, average, or late maturing based on age at menarche. Weight was measured to calculate body mass index (BMI) percentile. Weight management behavior and timing of menarche were self-reported via a survey. Descriptive characteristics were calculated for boys and girls separately. χ2 Tests of proportion were used to test WMB by BMI percentile. Logistic regression analyses were conducted to examine the likelihood of engaging in WMB by maturity offset and, for girls, timing of menarche. Students with weight ≥85th percentile were more likely to describe themselves as overweight and report trying to lose weight through exercise or calorie restriction ( P < .0001). A 1-year increase in maturity offset was associated with youth being 31% more likely to perceive themselves as overweight but less likely to report calorie restriction (odds ratio [OR] = 0.87). Average maturing girls were more likely than premenarcheal girls to exercise, restrict calories, or fast to lose weight (OR = 3.27, 2.11, and 3.27, respectively). Mexican American youth are engaging in WMB, even when their weight status is <85th percentile. The appropriateness of weight management counseling may need to consider a child's stage of growth.

Changes in precipitation extremes over the Kelantan River Basin, Malaysia

ABSTRACTRegional spatio‐temporal assessment of extreme precipitation is essential to develop better climate adaptation and mitigation strategies. This study evaluated trends in precipitation extremes from 1985 to 2014 in the Kelantan River Basin (KRB), Malaysia. Forty‐one climate stations that had &lt;10% missing data, and which passed the data quality control and homogeneity tests were selected. Trends of 14 precipitation extreme indices recommended by the Expert Team on Climate Change Detection and Indices that related to duration, threshold, absolute, relative and percentile indices were analysed using the Mann–Kendall and Sen's tests. Generally, most of the regional precipitation extremes' indices had increased trends, except the consecutive dry days and consecutive wet days, which are quite consistent with global scale trends studies. On a monthly scale, the maximum 5‐day precipitation amount (Rx5d) had increasing trends in January (34.91 mm decade−1) and December (13.96 mm decade−1), by field significance at 95% confidence level. For spatial context, most of the stations with significant trends were distributed in the south‐western (mountainous) and northern (near‐coastal) regions. In the Tropics, the KRB's extremes indices trends had a similar pattern to the West Pacific, Indian Ocean and Caribbean regions, but were different from Western Thailand, the South China Sea and the North Inter‐tropical Convergence Zone, showing that trends of precipitation extreme events are different regionally. Overall, the Pacific Decadal Oscillation, Multivariate El‐Niño Southern Oscillation Index, Indian Ocean Dipole and Madden‐Julian Oscillation had a significant relationship with all precipitation extremes' indices, and they are contributors to climate changes in this basin.

Are Croatian school-aged children really obese?

Background In 21st century, overweight and obesity among children became growing public health problem. Body mass index (BMI) is a measure used to determine childhood overweight and obesity. In children and adolescent, the healthy range for BMI varies based on age and gender. The aim of this study was to compare Croatian body mass index (BMI) percentiles for school-aged …

Does fitness make the grade? The relationship between elementary students’ physical fitness and academic grades

Background and Objective: Increased emphasis on academic outcomes has reduced the amount of time spent in physical education and other school physical activity opportunities in many schools in the USA. However, physical fitness is a positive predictor of academic performance on standardised tests, and students who perform better on fitness measures may earn higher grades. The purpose of this study was to evaluate the relationship between physical fitness and teacher-assigned grades in fourth-grade students and examine whether the relationship is moderated by body composition, gender or ethnic background. Design: Cross-sectional design. Students’ fitness levels were assessed mid-way through the spring semester, and their third-quarter grades were obtained from the schools. Participants and setting: Fourth-grade students ( N = 80; 38 female students; 65 non-Hispanic or Latino) from two elementary schools in the south-western USA. Method: Students completed physical fitness measures using standard procedures from the FITNESSGRAM protocol, and standardised teacher-assigned grades in reading, writing, mathematics, social studies and science were compiled. Linear regression and multivariate analysis of variance (MANOVA) were performed to examine the relationship between physical fitness measures and average grades, and examine whether differences in fitness and grades existed between gender, ethnic background and body mass index (BMI) percentile rank. Results: Aerobic fitness, as measured by the number of 20-m Progressive Aerobic Cardiovascular Endurance Run (PACER) laps completed, had a significant influence on reading, writing, mathematics and science grades. There were no significant interactions between aerobic fitness and ethnic background, gender or BMI percentile rank, meaning that aerobic fitness was the largest specific influence on average teacher-assigned grades. Conclusion: Positive associations exist between physical fitness and academic performance, suggesting activities that help children improve their physical fitness ought to be a central component of physical education and broader school physical activity programmes.

Prevalence and predictors of obstructive sleep apnoea in young children with Down syndrome

BackgroundChildren with Down syndrome (DS) are vulnerable to obstructive sleep apnoea (OSA) because of their unique craniofacial anatomy and hypotonia. Understanding the predictors of OSA in DS may enable targeted screening. MethodsChildren with DS (n = 202) aged from six months to below six years (110 boys) were recruited from three UK children's hospitals. The clinical assessment included height, weight and tonsillar size. The parents either set up cardiorespiratory polygraphy at home or chose laboratory studies. Studies with less than four hours of interpretable data were repeated where possible. American Academy of Sleep Medicine (AASM) 2012 scoring criteria were used to derive an obstructive apnoea/hypopnoea index (OAHI). Predictors of moderate to severe OSA were examined. ResultsIn total, 188/202 (93%) participants were successfully studied. Of these, 169 studies were completed at home and 19 in a sleep laboratory. Moderate to severe OSA, defined by an OAHI of >5/h, was found in 14% and mild to moderate OSA (1/h≥OAHI <5/h) was found in 59% of the children. Male gender and habitual snoring predicted OSA but did not have independent predictive power in the presence of the other factors. Age in months, body mass index (BMI) centile and tonsillar size did not predict OSA. ConclusionsModerate to severe OSA is common in very young children with DS. Examination of tonsillar size did not predict OSA severity. Population-based screening for OSA is recommended in these children, and domiciliary cardiorespiratory polygraphy is an acceptable screening approach. Further research is required to understand the natural history, associated morbidity, optimal screening methodology and treatment modality for OSA in these children.

Similarities and Differences of Neuropsychological Profiles in Children and Adolescents with Anorexia Nervosa and Healthy Controls Using Cluster and Discriminant Function Analyses.

This study aimed to identify discrete neuropsychological profiles and their relationship to clinical symptoms in 253 female children and adolescents with anorexia nervosa (AN) and 170 healthy controls (HCs) using a standardised neuropsychological assessment battery. Hierarchical cluster analysis was used to identify the optimum number of clusters, and participants were assigned using K-means cluster analysis. Confirmatory discriminant function analysis determined which combination of neuropsychological variables best distinguished the clusters. Three distinct clusters in the AN sample emerged- AN cluster 1 (19%) - "neuropsychologically low average to average"; AN cluster 2 (33%) - "verbal/visuo-spatial discrepancy"; and AN cluster 3 (48%) - "verbally strong and neuropsychologically average to high average". Two distinct clusters in HCs were identified. HC cluster 1 (48%) demonstrated poor visuo-spatial memory scores and high verbal fluency scores, whilst HC cluster 2 (52%) scored within the average range on all neuropsychological tasks. Neuropsychological performance was associated with clinical symptoms of body mass index centile, Eating Disorder Examination subscale and global score, anxiety, depression and obsessions, and compulsions between the AN and HC groups. However, niether significant differences emerged between AN clusters only nor HC clusters only at the post-hoc level. An underlying neuropsychological heterogeneity may exist in AN. We encourage future studies to investigate whether the identified profiles and their association with clinical characteristics are replicable. We cautiously suggest that neuropsychological profiling may have potential to both inform future research and have possible clinical benefits through individually tailored treatment strategies.

Relationship between α-MSH, soluble leptin receptor, MC4R polymorphism and BMI in Thai children and adolescents

In order to evaluate the mechanism of disturbance of melanocortin signaling in different groups of Thai children and adolescents classified according to body mass index (BMI) pe rcentile for age by The Centers for Disease Control and Prevention (CDC) growth charts, and �-melanocortin stimulating hormone (�-MSH), soluble leptin receptor and melanocortin 4 receptor (MC4R) polymorphism were studied. 149 male and 127 female children and adolescent Thai subjects with age range between 5-19 years were selected. Statistically significant differ ence of serum leptin receptor concentration between under weight (< 5th percentile), possible at risk for underweight (between 5th and 15th percentile), probably healthy (between 15th and 85th percentile); at risk for overweight (between the 85th and 95th percentile) and overweight (over the 95th percentile) were found. The levels of �-MSH were not significantly different when comparing the gro ups. Heterozygous of MC4R polymorphism (Val103Ile) were found in underweight, possible at risk for underweight and probably healthy group which might have been the cause of lower BMI for age even they have had normal serum �-MSH concentration. Using the logistic regression analysis, the group of risk for being overweight and overweight was statistically significant with �-MSH. This study supported a positive correlation between �-MSH and BMI with ages of Thai children and adolescents group.

PREVALENCE OF MALNUTRITION IN CHILDREN WITH CHRONIC HEPATITIS B INFECTION.

There have been limited studies investigating the impact of chronic hepatitis B virus infection on the growth of children. Our objective was to investigate the prevalence of malnutrition in children with chronic hepatitis B infection. The nutritional status of patients was retrospectively evaluated in the outpatient Clinic of Pediatric Gastroenterology between February and November 2014. During the study, biochemical laboratory parameters, duration of disease, liver biopsy scores, and medication were evaluated. Additionally body mass index and body mass index centiles were calculated. Of the 96 patients in this study, 68 were male and 28 were female, and the mean age was 144.7±43.9 months and 146.1±47.3 months, respectively. According to body mass index centiles five (5.2%) patients were underweight, seven (7.3%) patients were overweight, and seven (7.3%) patients were obese. Moderate rates of malnutrition (including obesity) were found in chronic hepatitis B infection. Additional nutritional status information of healthy and sick children should be assessed in the infection's early period, and timely interventions should be initiated.

Percentile indices for assessing changes in heavy precipitation events

Many climate studies assess trends and projections in heavy precipitation events using precipitation percentile (or quantile) indices. Here we investigate three different percentile indices that are commonly used. We demonstrate that these may produce very different results and thus require great care with interpretation. More specifically, consideration is given to two intensity-based indices and one frequency-based index, namely (a) all-day percentiles, (b) wet-day percentiles, and (c) frequency indices based on the exceedance of a percentile threshold. Wet-day percentiles are conditionally computed for the subset of wet events (with precipitation exceeding some threshold, e.g. 1 mm/d for daily precipitation). We present evidence that this commonly used methodology can lead to artifacts and misleading results if significant changes in the wet-day frequency are not accounted for. Percentile threshold indices measure the frequency of exceedance with respect to a percentile-based threshold. We show that these indices yield an assessment of changes in heavy precipitation events that is qualitatively consistent with all-day percentiles, but there are substantial differences in quantitative terms. We discuss the reasons for these effects, present a theoretical assessment, and provide a series of examples using global and regional climate models to quantify the effects in typical applications. Application to climate model output shows that these considerations are relevant to a wide range of typical climate-change applications. In particular, wet-day percentiles generally yield different results, and in most instances should not be used for the impact-oriented assessment of changes in heavy precipitation events.

Abstract P039: American Indian Youth Wellness Initiative

American Indian youth have the highest prevalence of obesity of all ethnic groups in the U.S. Obese individuals are at higher risk for cardiovascular disease, high blood pressure, dyslipidemia, type 2 diabetes mellitus and stroke. Reducing childhood obesity will require effective prevention strategies that focus on environments and promotion of physical activity and a healthy diet. Objective: To understand trends in the prevalence of obesity and severe obesity among American Indian tribal youth during the past 20 years. Methods: Participants included American Indian boys and girls aged 10-15 years from 14 different tribes in the Southwest, primarily Arizona, who attended a 1-week residential summer wellness camp from 1995 to 2015. Height and weight were measured on the first day of camp; sex- and age-specific body mass index (BMI) percentile and BMI z-score were computed using CDC SAS code. Obesity in childhood is defined by age- and sex-specific BMI percentile greater than or equal to the 95th percentile; severe obesity is defined as BMI ≥ 120% of the 95th percentile of BMI-for-age or as BMI ≥ 35.0 kg/m2. Chi-square tests and two-sample t-tests were used to determine the effects of sex and time on obesity and severe obesity. The significance threshold was set at p &lt; .05. Results: Our sample was comprised of 354 youth, 154 males (43.5%) and 200 females (56.5%), aged 12.7 ± 1.6 years (mean ± SD). Across the 20-year period, the prevalence of obesity was 80.2% (284 of 354) overall, and was greater in males (85.7%; 132 of 154) than females (76.0%; 152 of 200, p = 0.02). Likewise, the prevalence of severe obesity was greater in males (65.6%; 101 of 154) than females (50.0%; 100 of 200, p = 0.003) and was 56.8% (201 of 354) overall. The mean BMI-for-age percentile and z-score were 94.5 ± 11.9 and 2.05 ± 0.71, respectively; BMI z-score was higher in males (2.17 ± 0.7) than in females (1.96 ± 0.7, p = 0.004). There were no clear trends in obesity among our American Indian youth campers from 1995 to 2015, but the prevalence was high in all years (range 62.5 - 95.0%; 10 of 16 youth in 2011 - 19 of 20 youth in 2003). Conclusions: Throughout the 20-year period, there was consistently a high prevalence of obesity and severe obesity among American Indian tribal youth. Boys displayed a higher prevalence and severity of obesity relative to girls. Given the strong association between obesity in youth and the risk for chronic disease, our results underscore the critical need to intervene early in regards to establishing healthy eating and exercise behaviors among American Indian youth.

Abstract P128: Accelerometer-determined Moderate to Vigorous Physical Activity and the Cardiovascular Response to Stress in Children

Background: Physical activity (PA) has been associated with lower cardiovascular reactivity in adults, but little data is available in children. The purpose of this study was to examine the relationship between PA and cardiovascular reactivity to stress in children. Methods: This study sample included children from the Oswego Lead Study (n=79, 46% female, 9-11 years old). Impedance cardiography was performed while children participated in a stress response protocol consisting of three stress tasks in random order, separated by 8-minute intertask rest periods. Change in heart rate (HR) and systolic and diastolic blood pressure (SBP and DBP) (from baseline to stress level) were standardized within each task, then averaged across tasks (zMean [[Unable to Display Character: &amp;#8710;]]). Total peripheral resistance (TPR) was calculated using BP and cardiac output (CO); TPR = ([(SBP-DBP)/3] + DBP)/CO X 80. Percent change in TPR (from baseline to stress level) was standardized within each task, and then averaged across tasks (zMean %[[Unable to Display Character: &amp;#8710;]]). Children were also asked to wear Actigraph accelerometers on their wrists for 3 days to measure intensity and duration of PA and sedentary time. Results: In multivariable regression models, moderate to vigorous (MV) PA was associated with a lower body mass index (BMI) percentile, lower resting heart rate (HR), and lower TPR response to stress (Table 1; all p &lt; 0.05). After additional adjustment for BMI, MVPA was also associated with lower diastolic blood pressure response to stress (p &lt; 0.05). Sedentary time was not associated with resting measures or cardiovascular responses to stress (data not shown). Conclusions: A modest relation was observed between MVPA and vascular reactivity to stress in children after accounting for the effect of BMI. These data provide confirmatory evidence that the promotion of PA recommendations for children are important for cardiovascular health.

Spatial and temporal features of summer extreme temperature over China during 1960–2013

Based on daily air temperature data from 772 stations in China, the present study uses absolute index and percentile index to investigate the spatial and temporal features of summer extreme temperature over China during the period 1960–2013. The analysis indicates that Xinjiang and southeastern China are two major domains where extreme heat events frequently occur and that the number of heat day (NHD) and the frequency of heat wave (FHW) both show an increasing trend throughout the country except for Shandong and Henan provinces where a decreasing trend is identified. Although the two leading empirical orthogonal function (EOF) modes of the NHD and the FHW based on the absolute index and percentile index have differences, the time series of the first principal components (PC1) are consistent; PC1 depicts opposite trends from 1960 to late 1990s and during the late 1990s to 2013. According to the climatology and EOF modes, four sub-regions are chosen: Chuanyu, Huanghuai, Southeast, and Xinjiang area. The inter-decadal variation over the four sub-regions differs, but the NHD and the FHW significantly increase after the mid-1990s. Based on Mann-Kendall method, it is found that the NHD and the FHW over Chuanyu exhibited abrupt shifts in 1978 and 2000; sudden shifts occurred in 1973 and 2000 over Huanghuai; an abrupt shift occurred over the Southeast area in 2003.

Trends in extreme temperature over Nigeria from percentile‐based threshold indices

ABSTRACTThis study analyses spatial and temporal trends in extreme temperature indices over Nigeria. The percentile indices were calculated from newly homogenized daily minimum and maximum temperature data for the period 1971–2012 for 21 stations in Nigeria. Indices describing the characteristics of hot extremes and cold extremes are calculated with the RClimDex software. The annual and seasonal trends in these indices are obtained using the ordinary least square fit and the statistical significance tested using the R‐based modified Mann–Kendall test. We examine characteristics of these indices for the entire country and separately for the three geographical zones in Nigeria: Guinea, Savanna, and Sahel. The spatial and temporal patterns of trends in the indices indicate that Nigeria has experienced statistically significant increase in the frequency of hot extreme and decrease in cold extreme events. Although majority of the stations have significant trends in warm days and warm nights, the annual trend is greatest in warm nights. In addition, the rate of warming in minimum temperature (‘warm nights’) is stronger in June, July, August (JJA) and September, October, November (SON) compare with December, January, February (DJF) and March, April, May (MAM). As for the trends in cold days and cold nights, the trends in cold nights are larger than for cold days at both the annual and seasonal scales. The regional analysis indicates that trends in warm nights and cold nights are most pronounced in Guinea and Sahel regions.

The placenta is the center of the chronic disease universe

Over the past quarter century it has become clear that adult onset chronic diseases like heart disease and type 2 diabetes have their roots in early development. The report by David Barker and colleagues showing an inverse relationship between birthweight and mortality from ischemic heart disease was the first clear-cut demonstration of fetal programming. Because fetal growth depends upon the placental capacity to transport nutrients from maternal blood, it has been a suspected causative agent since the original Barker reports. Epidemiological studies have shown that placental size and shape have powerful associations with offspring disease. More recent studies have shown that maternal phenotypic characteristics, such as body mass index and height, interact with placental size and shape to predict disease with much more precision than does birthweight alone. For example, among people in the Helsinki Birth Cohort, who were born during 1924–1944, the risk for acquiring colorectal cancer increased as the placental surface became longer and more oval. Among people in whom the difference between the length and breadth of the surface exceeded 6 cm, the hazard ratio for the cancer was 2.3 (95% CI 1.2–4.7, p=0.003) compared with those in whom there was no difference. Among Finnish men, the hazard ratio for coronary heart disease was 1.07 (1.02–1.13, P =0.01) per 1% increase in the placental weight/birthweight ratio. Thus, it appears that the ratio of birthweight to placental weight, known as placental efficiency, predicts cardiovascular risk as well. Babies born with placentas at the extremes of efficiency are more vulnerable for adult onset chronic diseases. Recent evidence suggests that placental growth patterns are sex specific. Boys’ placentas are, in general, more efficient than those made by girls. Another recent discovery is that the size, shape and efficiencies of the placenta can change over years of time with very narrow confidence limits. This suggests that the growth of the placenta within a population of women is strongly affected by their nutritional environment. Even though it is known that an individual placenta can expand to improve its nutrient acquisition capacity in the first 2/3rd of gestation, the mechanisms by which placentas grow in response to a specific nutritional environment are not known. Discovering those mechanisms is the task of the current generation of scientists. While it may seem obvious that good nutrition is highly important for women who are pregnant because it supports optimal placentation and fetal development, more research is needed to determine the mechanisms by which maternal nutrition, placenta growth and fetal health are related.

Sudden cardiac arrest risk stratification based on 24-hour Holter ECG statistics.

This study examined the feasibility of using indices obtained from a long term Holter ECG record for sudden cardiac arrest (SCA) risk stratification. The ndices tested were the QT-RR interval co-variability and the alternans ratio percentile (ARP(θ)) which is defined as the θ(th) percentile of alternans ratios over a 24 hour period. The QT-RR interval co-variabilities are evaluated by the serial correlation coefficient between QT and RR trend sequences (QTRC). Previously reported Kalman filter technique and a simple smoothing spline method for the trend estimation are compared. Parameter θ in the alternans ratio percentile index was optimized to achieve the best classification accuracy. These indices were estimated from 26 cardiovascular outpatients for Holter ECG record. Patients were classified into high and low risk groups according to their clinical diagnosis, and the obtained indices were compared with those of 25 control subjects. A risk stratification using the two indices QTRC and ARP(θ) yielded an average sensitivity of 0.812 and a specificity of 0.925. The sensitivities and specificities of all three categories exceeded 0.8 except for the sensitivity to detect the high-risk patient group. Other short-term ECG parameters may need to be incorporated in order to improve the sensitivity.