Higher serum ferritins are associated with higher blood pressure: A cross-sectional study.

The aim of the study was to investigate the association between serum ferritin and hypertension among American adults from National Health and Nutrition Examination Survey (NHANES) 1999 to 2018. A total of 16,125 participants were included. Weighted logistic regression and subgroup analyses were performed to explore the association. We found that serum ferritin was closely correlated to hypertension. Individuals with high serum ferritin were more likely to have higher systolic or diastolic blood pressure (SBP, DBP) than those with lower serum ferritin. Restricted cubic spline showed a significant non-linear association between serum ferritin and SBP/DBP. Higher level of serum ferritin (Q3 74.1-147 µg/L and Q4 > 147 µg/L) was found to have positive association with high SBP [Q3 (OR: 1.246, 95% CI:1.020-1.523), Q4 (OR: 1.354, 95% CI:1.096-1.674)], and hypertension [Q3 (OR: 1.283, 95% CI:1.099-1.499), Q4 (OR: 1.424, 95% CI:1.197-1.63)] in the whole population. In people aged between 20 and 60, subjects with high serum ferritin were significantly associated with a higher risk of hypertension, but in those over 60, the relationship between serum ferritin level and hypertension is negative. A non-linear association between serum ferritin and SBP, as well as DBP, was discovered. There was age difference in association between serum ferritin and hypertension in American adults, and further researches were needed to understand the mechanisms behind the difference.

Association of height, foot length, and pubertal development in children aged 3-18: a cross-sectional survey in China.

Objective: This study aimed to analyze the growth patterns of height and foot length (FL) among Chinese children aged 3-18 and examine their associations with puberty development. Methods: A cross-sectional survey was conducted in September 2022 in Beijing. Data were collected through questionnaires and on-site physical examinations. The growth patterns and velocity of height and FL in different age groups were described, and their associations with puberty development were analyzed. Results: From an age perspective, the peak FL growth occurred between 9 and 11 years (boys were 11 years and girls were 9 years), while the peak height growth occurred at 11 ~ 13 years for boys and 9 ~ 11 years for girls. Additionally, boys and girls reached 99.0% of their final FL at the ages of 14 and 13, respectively, while they reached 99.0% of their final height at the ages of 16 and 15, respectively. From the perspective of Tanner stage, the age of peak FL growth in boys coincided with the age of the G2 stage, while in girls it occurred slightly earlier than the mean age of the B2 stage. The peak height growth for both boys and girls occurred between Tanner stages 2 and 3. Conclusion: Boys and girls reach their peak FL growth at 11 and 9 years old, respectively, which were both 2 years earlier than their peak height growth. The peak FL growth occurred around the onset of puberty, while the peak height growth occurred between Tanner stages 2 and 3.

Uric acid mediated the relationship between obesity and hypertension in children and adolescents: A population­based cohort study.

BACKGROUND AND AIM: Obesity and hyperuricemia (HUA) often coexist and have been widely accepted as risk factors for hypertension, but the role of uric acid (UA) in the relationship between obesity and hypertension remains unknown in children and adolescents. METHODS AND RESULTS: A total of 7525 subjects aged 6-16 years were from the School-based Cardiovascular and Bone Health Promotion Program (SCVBH) at baseline (2017) and followed up in 2019. Multivariable logistic regression with interaction terms, cross-lagged panel analysis, and causal mediation model were applied to delineate the joint impact of obesity and HUA on hypertension, including the interaction effect, the temporal association, and the mediating effect of UA in the relationship between obesity and hypertension. There were 10.8 % of the participants with normotension at baseline developed hypertension after two years of follow-up. Cross-lagged panel analysis showed that the two-time point association was significant only from baseline BMI to follow-up UA (ß1 = 0.302, P < 0.001), but not from baseline UA to follow-up BMI (ß2 = 0.002, P = 0.745). Multivariable logistic regression showed that both obesity and HUA increased the risk of hypertension, but no interaction effect between HUA and obesity. The causal mediation analysis found that UA partially mediated the association between BMI and SBP (mediate proportion: 20.3 %, 95 % CI: 17.4-22.9 %) or DBP (mediate proportion: 11.9 %, 95 % CI: 3.9-18.2 %). The results were consistent in the analysis of systolic hypertension rather than diastolic hypertension. CONCLUSIONS: It is mediating effect that UA played in the progress from obesity to hypertension, particularly systolic hypertension in children and adolescents.

Longitudinal association of serum 25-hydroxyvitamin D levels with metabolically healthy body size transition in children and adolescents: A prospective cohort study with 2 years of follow-up.

BACKGROUND AND AIMS: Although the associations of vitamin D with obesity and metabolic abnormalities have been reported, the role of vitamin D in the transition of obesity phenotype remains unclear but is highly desired since it is crucial to identify potential methods for obesity management. Therefore, we aimed to investigate the relationship between vitamin D and the risk for metabolically unhealthy obesity (MUO) or metabolically healthy obesity (MHO) in metabolically healthy children with 2 years of follow-up. METHODS: Data were collected from a population-based cohort consisting of 6424 metabolically healthy children aged 6-16 years at baseline. Metabolic abnormalities including hypertension, high triglycerides (TG), low high-density lipoprotein cholesterol (HDL-C), hyperglycemia, and hyperuricemia were assessed both at baseline and follow-up. Baseline serum 25-hydroxyvitamin D (25[OH]D) concentrations were measured as exposure. The obesity phenotype transition was evaluated by weight status with the combination of metabolic health status from baseline to follow-up. RESULTS: During a 2-year follow-up, 889 (13.8 %) incident MUO cases occurred. For participants with obesity, each 10 nmol/L increment in 25(OH)D concentrations was associated with a 21 % (95%CI: 13 %∼43 %) and a 7 % (95%CI: 1 %∼14 %) decreased risk in high TG and hyperuricemia, respectively. A 51 % (95%CI: 22 %∼69 %) lower risk of MUO was observed in participants with sufficient vitamin D levels (≥50 nmol/L) compared to those with vitamin D deficiency (<30 nmol/L). Besides, among children who were MHO at baseline, those with sufficient vitamin D levels (≥50 nmol/L) were more likely to transition to metabolically healthy normal weight (MHNW) than vitamin D deficient individuals (<30 nmol/L). CONCLUSIONS: Vitamin D may prevent the development of MUO and help increase the transition from MHO to MHNW. The findings highlight that vitamin D might be an effective nutrient for obesity management.

A comparison of bioelectrical impedance analysis and air displacement plethysmography to assess body composition in children.

Background: Accurate assessment of body composition (BC) is important to investigate the development of childhood obesity. A bioelectrical impedance analysis (BIA) device is portable and inexpensive compared with air displacement plethysmography (ADP) for the assessment of BC and is widely used in children. However, studies of the effectiveness of BIA are few and present different results, especially in pediatric populations. The aim of this study was to evaluate the agreement between BIA and ADP for estimating BC. Methods: The BC of 981 Chinese children (3-5 years) was measured using the BIA device (SeeHigher BAS-H, China) and ADP (BOD POD). Results: Our results showed that BIA underestimated fat mass (FM) and overestimated fat-free mass (FFM) in normal weight children (P < 0.05), but the opposite trend was shown in children with obesity (P < 0.05). The agreement between FM and FFM measured by the two methods was strong (CCC > 0.80). The linear regression equation of 5-year-old children was constructed. Conclusion: The SeeHigher BAS-H multi-frequency BIA device is a valid device to evaluate BC in Chinese preschool children compared with ADP (BOD POD), especially in 5-year-old children or children with obesity. Further research is needed to standardize the assessment of BC in children.

Relationships between antibiotic exposure and asthma in adults in the United States: results of the National Health and Nutrition Examination Survey between 1999 and 2018.

Objectives: To investigate the relationship between antibiotic exposure and asthma in adults in the United States. Methods: Data was obtained from the National Health and Nutrition Examination Survey (NHANES) conducted between 1999 and 2018. A total of 51,124 participants were included, excluding those who were aged < 20 years, female participants who were pregnant, and individuals who did not complete the prescription medications questionnaire and the medical conditions questionnaire regarding asthma status. Antibiotic exposure was defined as the utilization of antibiotics within the past 30 days, categorized based on the Multum Lexicon Plus therapeutic classification system. Asthma was defined as having a history of asthma or having an asthma attack or wheezing symptoms in the past year. Results: The risk of asthma was found to be 2.557 (95% CI: 1.811, 3.612), 1.547 (95% CI: 1.190, 2.011) and 2.053 (95% CI: 1.344, 3.137) times greater in participants who had used macrolide derivatives, penicillin and quinolones in the past 30 days, respectively, compared with those not using antibiotics. After adjusting for demographic covariates and asthma-related factors, only macrolides derivatives were significantly associated with asthma in the 20-40 and 40-60 age groups. For individuals over 60 years old, quinolones were significantly associated with asthma. The effect of different types of antibiotic with asthma varied in male and female populations. Moreover, higher socioeconomic status, greater BMI, younger age, smoking habits, history of infection, chronic bronchitis, emphysema, and family history of asthma were all identified as risk factors for asthma. Conclusion: Our study indicated that three types of antibiotics were significantly associated with asthma in different subgroups of the population. Therefore, the use of antibiotics should be more strictly regulated.

Relationships for vitamin D with childhood height growth velocity and low bone mineral density risk.

Objective: To investigate how serum 25-hydroxyvitamin D (25[OH]D) affects height growth velocity and the risk of low bone mineral density (BMD) in children. Design: A population-based prospective cohort study. Patients and methods: A total of 10 450 participants with complete follow-up records from a cohort were included in the current study. Serum 25(OH)D concentrations were measured at baseline and 2-year follow-up, and the average of 2-time measurements was used for analysis. Low BMD was defined as calcaneus speed of sound Z-score ≤ -1. The associations of vitamin D with height growth velocity and the risks of incident low BMD were evaluated using adjusted ß and risk ratio (RR). Results: After multivariable adjustment, an inverse L-shaped association between serum 25(OH)D concentrations and height growth velocity was observed, leveling off up to 40-60 nmol/L. Overall, each 10 nmol/L higher serum 25(OH)D concentration was associated with a 0.15 cm/year higher height growth velocity (P < 0.001) and a 7% decreased risk of low BMD [RR (95%CI): 0.93 (0.87~0.98)]. Compared to those with vitamin D deficiency, participants who had sufficient vitamin D had a 22% lower risk for low BMD [RR(95%CI): 0.78 (0.62~0.98)]. However, no significant associations between vitamin D and the risk of low BMD were found in overweight and obese children. Conclusion: These findings highlight the importance of maintenance of sufficient 25(OH)D concentrations and healthy body weight during childhood in height growth and bone health promotion.

Temporal trends in cardiovascular health among Chinese urban children and adolescents, 2004-2019 pre-pandemic COVID-19.

Objective: Little is known about pre-pandemic cardiovascular health (CVH) status and its temporal variation in Chinese children. Thus, we aimed to evaluate the secular trends and associated factors of CVH in Chinese urban children from 2004 to 2019. Methods: We identified 32,586 individuals in Beijing, aged 6 to 18 years, from three independent cross-sectional studies conducted in 2004, 2014, and 2019, respectively. CVH was assessed by 7 metrics according to modified American Heart Association criteria, including smoking, physical activity, diet, body mass index, total cholesterol, blood pressure, and fasting glucose. Multivariable logistic regression was used to assess the associations between sociodemographic characteristics and the ideal CVH status. Results: The proportion of ideal CVH decreased from 27.7% (boys 26.6%, girls 28.9%) in 2004 to 4.2% (boys 3.8%, girls 4.8%) in 2014, and then increased to 16.2% (boys 13.5%, girls 18.9%) in 2019. Overall, ideal smoking was the most prevalent CVH component during 2004-2019 (2004, 97.5%; 2014, 92.9%; 2019, 98.0%), while ideal physical activity (2004, 27.6%; 2014, 14.4%; 2019, 28.0%) and dietary intake (2004, 26.0%; 2014, 10.7%; 2019, 23.5%) were the least prevalent components. Notably, the proportion of ideal body mass index (2004, 77.5%; 2019, 59.7%) and blood pressure (2004, 73.6%; 2019, 67.3%) continuously decreased from 2004 to 2019. Girls, parental normal weight status, free of family CVD history, and lower levels in fat mass were associated with higher odds of ideal CVH. Conclusion: The cardiovascular health in Chinese urban children deteriorated during 2004-2019. Distinct strategies are required to mitigate socioeconomic inequity in the intervention of CVH promotion.

The diverse life-course cohort (DLCC): protocol of a large-scale prospective study in China.

The Diverse Life-Course Cohort (DLCC) is a large-scale prospective study including around 130,000 participants in mainland China. The primary aims of DLCC include contributing to knowledge on noncommunicable chronic disease determinants, particularly cardiometabolic diseases, and exploring the long-term effect of ambient air pollutants or other environmental risk factors on health among all-age populations. The cohort consists of several sub-populations that cover the whole life-course and diverse resources: from premarital to adolescents, adults from workplace and communities ranged from 18 to 93 years old. Baseline assessment (2017-2021) included face-to-face standardized questionnaire interview and measurements to assess social and biological factors of health. Blood samples were collected from each participant (except for children younger than 6) to establish the biobank. DLCC consists of two visits. Visit 1 was conducted from 2017, and 114850 individuals from one of the world-class urban agglomerations: Beijing, Tianjin, and Hebei area were recruited. By the end of 2021, at least one follow-up was carried out, with an overall follow-up rate of 92.33%. In 2021, we initiated Visit 2, newly recruited 9,866 adults from Guangdong province (South China) and Hebei province (Central China), with research focuses on the comparations on ambient pollution hazards and other unique dietary or environmental risks for health. The baseline survey of Visit 2 was finished in July 2021. DLCC is still ongoing with a long-term follow-up design, and not limited by the current funding period. With reliable data and the well-established biobank which consists of over 120,000 individuals' blood samples, DLCC will provide invaluable resources for scientific research.

The Relationship between Fat Mass Percentage and Glucose Metabolism in Children and Adolescents: A Systematic Review and Meta-Analysis.

To assess the relationship between fat mass percentage (FMP) and glucose metabolism in children aged 0−18 years we performed a systematic review of the literature on Medline/PubMed, SinoMed, Embase and Cochrane Library using the PRISMA 2020 guidelines up to 12 October 2021 for observational studies that assessed the relationship of FMP and glucose metabolism. Twenty studies with 18,576 individuals were included in the meta-analysis. The results showed that FMP was significantly associated with fasting plasma glucose (FPG) (r = 0.08, 95% confidence interval (CI): 0.04−0.13, p < 0.001), fasting plasma insulin (INS) (r = 0.48, 95% CI: 0.37−0.57, p < 0.001), and homeostasis model assessment (HOMA)- insulin resistance (IR) (r = 0.44, 95% CI: 0.33−0.53, p < 0.001). The subgroup analysis according to country or overweight and obesity indicated that these associations remained significant between FMP and INS or HOMA-IR. Our results demonstrated that there is a positive relationship between FMP and FPG. Moreover, subgroup analysis according to country or overweight and obesity indicated that FMP is significantly associated with INS and HOMA-IR. This is the first known systematic review and meta-analysis to determine the associations of FMP with glucose metabolism in children and adolescents.

Characteristics of Body Composition Estimated by Air-Displacement Plethysmography in Chinese Preschool Children.

Objective: To describe the characteristics of body composition by air-displacement plethysmography (ADP) among Chinese preschool children. Methods: Preschool children were recruited from three kindergartens. Adiposity indices were evaluated using the ADP method. BMI, fat mass index (FMI), fat-free mass index (FFMI) and waist-to-height ratio (WHtR) were calculated. Overweight and obesity were diagnosed using the WHO reference. Analyses were executed by SPSS and MedCalc software. Smoothed curves were constructed using the lambda-mu-sigma (LMS) method. Results: This study evaluated the growth trend for body composition of ADP-based body fat indices based on a relatively large sample of preschool children, the first ever reported in China. A total of 1,011 children aged 3-5 years comprised our study population. BMI and FFMI increased with age, but the slope (P = 0.710) and y intercept (P = 0.132) in the BMI trend analysis demonstrated no differences between boys and girls. For the FFMI trend lines, the slope was significantly higher for boys than for girls (P = 0.013). The percentage of fat mass (FM%), FMI, and WHtR were negatively correlated with age for both sexes, except for FMI in girls (P = 0.094). The 95% CI regression lines for FM% according to different weight statuses intersected. Conclusions: ADP is applicable to estimating body composition among Chinese preschool children. Misclassifications might occur when overweight/obese status is defined based on surrogate indices.

The Relationship Between Fat-Free Mass and Glucose Metabolism in Children and Adolescents: A Systematic Review and Meta-Analysis.

Purpose: To assess the relationship between fat-free mass (FFM) and glucose metabolism in children 0-18 years of age. Methods: We performed a systematic review of the literature on Medline/PubMed, SinoMed, Embase, and the Cochrane Library using the PRISMA 2020 guidelines to 12 October 2021; this encompassed observational studies in which the relationship between FFM and glucose metabolism was assessed. Correlation coefficient (r), regression coefficient (ß), and odds ratio (OR) values in the studies were extracted and recorded as the primary data. "Agency for Healthcare Research and Quality" quality-assessment forms recommended for cross-sectional/prevalence studies were applied to evaluate the quality of the selected studies, and we executed R software to combine the pooled data. Results: We included eight studies comprising 13,282 individuals, five of which involved the assessment of the relationship between FFM and blood glucose, and four on the relationship between FFM and insulin resistance (IR). Our results showed that FFM was significantly associated with fasting plasma insulin levels (r = 0.34, 95% CI: 0.30-0.39, P < 0.001). Due to high heterogeneity or insufficient quantity of data, the studies of the relationship between FFM and fasting plasma glucose, HOMA-IR, or HbA1c were not congruent, and were therefore not suitable for meta-analysis. Conclusion: Our results indicated that FFM was significantly associated with fasting plasma insulin levels. As far as we have determined, this is the first-ever systematic review and meta-analysis of the associations between FFM and glucose metabolism in children and adolescents; and our results thus provide novel information to fill a gap in the literature in this area. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020150320, PROSPERO CRD42020150320.

Distinct causal effects of body fat distribution on cardiometabolic traits among children: Findings from the BCAMS study.

BACKGROUND AND AIMS: Observational studies reveal that different body fat measures are associated with cardiometabolic disease with different effects. However, causality is not reflected by such observations. To explore and compare the causal relationships of general obesity (measured by body mass index (BMI)), adipose obesity (measured by fat mass percentage (FMP)) and central obesity (measured by waist-to-height ratio (WHtR)) with cardiometabolic traits among children. METHODS AND RESULTS: We conducted one sample Mendelian randomization (MR) analysis in 3266 children from Beijing Children and Adolescents Metabolic Syndrome Study. Genetic instruments based on 28 SNPs were performed to explore and compare the causal associations of genetically BMI, FMP and WHtR with cardiometabolic traits. The genetic instruments were robustly correlated with observed BMI, FMP and WHtR. Each genetically 1-SD increment in BMI, FMP and WHtR were causally associated with increment in systolic blood pressure (SBP), diastolic blood pressure (DBP), log-transformed fasting plasma glucose (FPG), log-transformed HOMA-ß, and decrease in log-transformed high-density lipoprotein cholesterol (HDL), respectively (all P < 0.05 after Bonferroni correction). The receiver operating characteristic curve indicated that BMI and FMP showed stronger effects on SBP, DBP, HOMA-ß and HDL than WHtR (all P < 0.05). We also observed causal associations of BMI and FMP with log-transformed fasting insulin and HOMA-IR. CONCLUSIONS: The MR analysis based on population-based cohort indicated a causal relationship of adiposity and body fat distribution with cardiometabolic traits. When compared with central obesity, general obesity and adipose obesity might own stronger effects on blood pressure and blood lipids among children.

The Prevalence of Mycoplasma Pneumoniae Among Children in Beijing Before and During the COVID-19 Pandemic.

Objective: Mycoplasma pneumoniae (M. pneumoniae) is an important pathogen of community acquired pneumonia. With the outbreak of coronavirus disease 2019 (COVID-19), the prevalence of some infectious respiratory diseases has varied. Epidemiological features of M. pneumoniae in children from Beijing (China) before and during the COVID-19 pandemic were investigated. Methods: Between June 2016 and May 2021, a total of 569,887 children with respiratory infections from Children's Hospital Affiliated to Capital Institute of Pediatrics (Beijing, China) were included in this study. M. pneumoniae specific-IgM antibody in serum specimens of these patients was tested by a rapid immunochromatographic assay kit. The relevant clinical data of M. pneumoniae-positive cases were also collected, and analyzed by RStudio software. Results: The results showed that 13.08% of collected samples were positive for M. pneumoniae specific-IgM antibody. The highest annual positive rate was 17.59% in 2019, followed by 12.48% in 2018, 12.31% in 2017, and 11.73% in 2016, while the rate dropped to 8.9% in 2020 and 4.95% in 2021, with significant difference. Among the six years, the positive rates in summer and winter seasons were significantly higher than those in spring and autumn seasons (p < 0.001). The positive rate was the highest in school-age children (22.20%), and lowest in the infant group (8.76%, p < 0.001). The positive rate in boys (11.69%) was lower than that in girls (14.80%, p < 0.001). There were no significant differences in different seasons, age groups, or genders before and during the COVID-19 pandemic (p > 0.05). Conclusions: Our study demonstrated that an M. pneumoniae outbreak started from the summer of 2019 in Beijing. After the COVID-19 pandemic outbreak in the end of 2019, the M. pneumoniae positive rates dropped dramatically. This may be due to the restrictive measures of the COVID-19 pandemic, which effectively controlled the transmission of M. pneumoniae. The relationships between M. pneumoniae positive rates and season, age, and gender were not statistically significant before and during the COVID-19 pandemic.

The Association between Lead Exposure and Bone Mineral Density in Childhood and Adolescence: Results from NHANES 1999-2006 and 2011-2018.

There are few studies on lead's effect on bone mineral density (BMD) in childhood. In this study, we examined the association between lead exposure and BMD among 13,951 children and adolescents aged 8-19 years from NHANES 1999-2006 and 2011-2018. The whole blood lead levels (BLLs) were used as lead exposure biomarkers, and total BMD, subtotal BMD, lumbar spine BMD and limb BMD were used as outcome variables. The survey weighted multivariable generalized additive models (GAMs) with smoothing terms were used to explore the association between blood lead levels and BMDs, adjusted for age, sex, race/ethnicity, height, weight, family-income-to-poverty ratio and blood cadmium. Subgroup analyses stratified by sex and bony sites were further performed. We found an N-shaped curve association between BLLs and total BMD, subtotal BMD and limb BMD for males and females, whereas the association between BLLs and lumbar spine BMD was only significantly negative for females. The findings suggested that lead exposure had different effects on BMD of different bony sites (highly cortical or trabecular regions) in childhood and adolescence and had different effects on the same bone among different ages population and/or at different levels.

Vitamin D Trajectories and Cardiometabolic Risk Factors During Childhood: A Large Population-Based Prospective Cohort Study.

Background and Objectives: Vitamin D has been indicated to play an important role in the optimal function of the cardiovascular system. However, with limited evidence, it remains unclear whether vitamin D status transition during childhood would affect cardiometabolic risk factors. Thus, we aimed to identify the associations of the longitudinal trajectory of vitamin D status with cardiometabolic risk factors in children. Methods: A total of 10,482 participants with complete follow-up records from a large population-based prospective cohort study were included in this analysis. The 25-hydroxyvitamin D [25(OH)D] concentrations, blood pressure, blood lipids, and fasting blood glucose were determined. Vitamin D deficiency was defined as serum 25(OH)D concentrations below 30 nmol/L according to the Institute of Medicine recommendations. Based on the vitamin D status at baseline and follow-up, we identified four possible trajectories: (1) persistent non-deficiency (reference); (2) baseline non-deficiency to follow-up deficiency; (3) baseline deficiency to follow-up non-deficiency; (4) persistent deficiency. The relationships between cardiometabolic risk factors and vitamin D trajectories were evaluated using adjusted risk ratios (RRs). Results: Overall, 35.1 and 24.2% of participants had vitamin D deficiency at the baseline and follow-up, respectively, and 15.1% were under the condition of persistent vitamin D deficiency. Compared to children with persistent non-deficiency, those who shifted from non-deficiency at baseline to deficiency at follow-up had a 2.09-fold (95% CI: 1.36, 3.23) increased risk of high triglyceride (TG). Besides, children with altered vitamin D status from deficiency to non-deficiency during follow-up were still at a significantly higher risk of high total cholesterol (TC) than the reference group [RR (95% CI): 1.39 (1.04, 1.86)]. Finally, children with persistent vitamin D deficiency were at the highest risks of high TC [RR (95% CI): 1.61 (1.18, 2.19), P trend < 0.001], high low-density lipoprotein cholesterol (LDL-C) [RR (95% CI): 1.53 (1.04, 2.27), P trend = 0.046], and high TG [RR (95% CI): 1.96 (1.34, 2.87), P trend = 0.003]. Conclusion: Our results suggest that persistent vitamin D deficiency might increase the risk of dyslipidemia in children, and vitamin D deficiency could have has short- and long-term effects on TG and TC, respectively.

Long-Term Trends of Asthma Mortality in China from 2000 to 2019: A Joinpoint Regression and Age-Period-Cohort Analysis.

BACKGROUND: Trends of asthma mortality vary widely all over the world, while the trends in China over the past 15 years are unknown. The aim of this study was to assess the trends of asthma mortality in China. METHODS: Asthma deaths and demographic characteristics were collected from National Death Cause Datasets of Disease Surveillance System between 2004 and 2019. The data were analyzed with joinpoint regression analysis and age-period-cohort (APC) analysis for the mortality rate due to asthma in China. RESULTS: Asthma mortality declined from 2.4 (95% confidence interval (CI): 2.3-2.5) per 100,000 in 2004 to 1.6 (95% CI: 1.5-1.7) per 100,000 in 2019. Age-adjusted asthma mortality rates decreased for men and women in urban and rural areas from 2004 through 2019. The decreasing trend of the mortality rate has slowed down substantially during 2007 and 2009. After that, the decreasing trend has stabilized. The asthma mortality rates generally have a positive relationship with the age of the population when controlling for period and cohort. The period trend decreased and then increased when controlling for age and cohort. CONCLUSIONS: We should pay more attention to asthma management plans or treatment for aging people who are facing higher risk of asthma death.

Relationship between prepregnancy body mass index weight gain during pregnancy and offspring body composition during preschool age / 中国学校卫生

Objective@#To explore the relationship between prepregnancy body mass index, weight gain during pregnancy with preschool obesity and body composition in offspring, so as to provide evidence for gestational weight gain and childhood obesity prevention.@*Methods@#A total of 1 333 preschool children were recruited from 3 kindergartens in Tianjin from September to December 2020. Structured questionnaire was used to collect children s lifestyle information. Height, weight and body fat mass of children were assessed, and body fat percentage (FM%), fat mass index (FMI) and non fat mass index (FFMI) were calculated. Maternal medical records were collected and the mothers were grouped according to their prepregnancy weight status and weight gain during pregnancy. χ 2 test, t test, linear regression model and Logistic regression were used to analyze the differences of obesity and body composition among different groups.@*Results@#The prevalence of overweight and obesity in preschoolers was 12.7% and 7.7%. After adjusting maternal age and delivery, gestational age, gender, age and lifestyle of children, the correlation between maternal pre pregnancy BMI,gestational weight gain with obesity and body composition indexes of children in preschool age was statistically significant ( P <0.05). For mothers with normal weight before pregnancy, excessive weight gain during pregnancy increased risk of high FM% and high FMI in offspring ( OR=1.81, 1.68, P <0.05). There was no significant correlation between maternal weight gain during pregnancy with offspring obesity and body composition among mothers with prepregnant overweight or obesity.@*Conclusion@#Maternal weight status before pregnancy and weight gain during pregnancy are correlated with obesity and body composition in the preschool age of offspring. It is suggested that mothers should maintain appropriate weight status before and during pregnancy.

Long-term changes in body composition and their relationships with cardiometabolic risk factors: A population-based cohort study.

The aim of the present study was to classify the latent body fat trajectories of Chinese adults and their relationships with cardiometabolic risk factors. Data were obtained from the China Health Nutrition Survey for 3,013 participants, who underwent six follow-up visits between 1993 and 2009. Skinfold thickness and other anthropometric indicators were used to estimate body composition. The latent growth model was used to create fat mass to fat-free mass ratio (F2FFMR) trajectory groups. Blood pressure, fasting plasma glucose, total cholesterol, triglycerides, and high- and low-density lipoprotein-cholesterol were measured in venous blood after an overnight fast. Logistic regression was used to explore the relationships of F2FFMR trajectory with cardiometabolic risk factors. In men, four types of F2FFMR trajectory were identified. After adjustment for behavioral and lifestyle factors, age, and weight status, and compared with the Low stability group, the High stability group showed a significant association with diabetes. In women, three types of F2FFMR trajectory were identified. Compared to the Low stability group, the High stability group showed significant associations with diabetes and hypertension after adjustment for the same covariates as in men. Thus, in this long-term study we have identified three F2FFMR trajectory groups in women and four in men. In both sexes, the highly stable F2FFMR is associated with the highest risk of developing diabetes, independent of age and body mass. In addition, in women, it is associated with the highest risk of hypertension, independent of age and body mass.

Trends in abdominal obesity among Chinese children and adolescents, 1993-2015.

OBJECTIVES: The prevalence of general overweight and obesity defined by body mass index criteria has greatly increased in Chinese children and adolescents in recent decades. However, few studies have considered the trend in abdominal obesity in Chinese children and adolescents. This study aimed to examine the secular trends in waist circumference (WC), waist-to-height ratio (WHtR) and the prevalence of abdominal obesity among Chinese children and adolescents aged 6-17 years from 1993 to 2015. METHODS: A total of 11,985 children and adolescents aged 6-17 years participated in the China Health and Nutrition Survey, a continuous cross-sectional survey, conducted from 1993 to 2015. Abdominal obesity was defined as WC≥age- and sex-specific 90th percentile based on the reference from Chinese children and adolescents or WHtR≥0.50. RESULTS: After adjustment for age, sex and region, mean WC increased from 60.27 cm in 1993 to 64.31 cm in 2015 (p for trend <0.001), and mean WHtR increased from 0.430 to 0.434 (p for trend <0.05). The prevalence of abdominal obesity defined by WC reference increased from 5.0% in 1993 to 19.3% in 2015 and defined by WHtR reference increased from 6.4% in 1993 to 14.5% in 2015 (p for trend <0.001). CONCLUSIONS: The prevalence of abdominal obesity among Chinese children and adolescents aged 6-17 years has increased between 1993 and 2015.