Reevaluate secular trends of body size measurements and prevalence of hypertension among Chinese children and adolescents in past two decades

Bivariate relation of vascular health and blood pressure progression during childhood

BACKGROUND AND AIMS

Hypertension is a major risk factor for the development of cardiovascular disease (CVD) in adulthood. High blood pressure (BP) is associated with subclinical vascular impairments as early as childhood. We aimed to assess the association of retinal microvascular diameters and large artery pulse wave velocity (PWV) with progression of childhood BP.

METHODS

In our prospective Basel cohort study, 1171 children aged 6-8 years were screened for BP, body mass index, retinal vessel diameters and PWV using standardized protocols. After 4 years, all parameters were assessed in 749 children using the same protocols.

RESULTS

Children with narrower central retinal arteriolar diameters (CRAE) and higher PWV at baseline developed higher systolic BP after 4 years (β [95% CI] 0.6 [0.072 to 1.164] mmHg per 10 μm decrease, p = 0.026 and β [95% CI] 0.6 [0.331 to 0.838] mmHg per 0.1 m/s increase, p < 0.001, respectively). Children with increased systolic BP at baseline developed narrower CRAE and higher PWV at follow-up (β [95% CI] -3.3 [-4.43 to -2.09] μm per 10 mmHg increase, p < 0.001 and β [95% CI] 0.13 [0.10 to 0.16] m/s per 10 mmHg increase, p < 0.001, respectively).

CONCLUSIONS

Retinal arteriolar diameter and PWV independently predict progression of childhood BP, while initial BP is linked to development of micro- and macrovascular impairments, describing a bivariate temporal relationship between vascular health and BP. Childhood may present a window of opportunity for initiation of primary prevention strategies for the treatment of high BP to help prevent manifestation of CVD later in life.

Cardiorespiratory fitness and development of childhood cardiovascular risk: The EXAMIN YOUTH follow-up study

Background: Obesity- and hypertension-related cardiovascular (CV) risk has been shown to originate in childhood. Higher body mass index (BMI) and blood pressure (BP) have been associated with increased large artery stiffness and a lower microvascular arteriolar-to-venular diameter ratio (AVR) in children. This study aimed to investigate the association of cardiorespiratory fitness (CRF) with development of BMI, BP and vascular health during childhood. Methods: In our prospective cohort study, 1,171 children aged 6-8 years were screened for CRF, BMI, BP, retinal vessel diameters and pulse wave velocity using standardized protocols. Endurance capacity was assessed by 20 m shuttle run test. After 4 years, all parameters were assessed in 664 children using the same protocols. Results: Children with a higher CRF at baseline developed a significantly lower BMI (β [95% CI] -0.09 [-0.11 to -0.06] kg/m2, p < 0.001), a lower systolic BP (β [95% CI] -0.09 [-0.15 to -0.03] mmHg, p = 0.004) and a higher AVR (β [95% CI] 0.0004 [0.00004 to 0.0007] units, p = 0.027) after 4 years. The indirect association of CRF with development of retinal arteriolar diameters was mediated by changes in BMI. Conclusion: Our results identify CRF as a key modulator for the risk trajectories of BMI, BP and microvascular health in children. Obesity-related CV risk has been shown to track into adulthood, and achieving higher CRF levels in children may help counteract the development of CV risk and disease not only in pediatric populations, but may also help reduce the burden of CVD in adulthood. Registration: http://www.clinicaltrials.gov/ (NCT02853747).

Association of joint exposure to various ambient air pollutants during adolescence with blood pressure in young adulthood

The association of various air pollutants exposure during adolescence with blood pressure (BP) in young adulthood is uncertain. We intended to evaluate the long-term association of individual and joint air pollutants exposure during adolescence with BP in young adulthood. This cross-sectional study of incoming students was conducted in five geographically disperse universities in China during September and October 2018. Mean concentrations of particulate matter with diameters ≤2.5 μm (PM2.5 ), ≤10 μm (PM10 ), nitrogen dioxides (NO2 ), carbon monoxide (CO), sulfur dioxide (SO2 ), and ozone (O3 ) at participants' residential addresses during 2013-2018 were collected from the Chinese Air Quality Reanalysis dataset. Generalized linear mixed models (GLM) and quantile g-computation (QgC) models were utilized to estimate the association between individual and joint air pollutants exposure and systolic blood pressure (SBP), diastolic blood pressure (DBP), and pulse pressure (PP). A total of 16,242 participants were included in the analysis. The GLM analyses showed that PM2.5 , PM10 , NO2 , CO, and SO2 were significantly positively associated with SBP and PP, while O3 was positively associated with DBP. The QgC analyses indicated that long-term exposure to a mixture of the six air pollutants had a significant positive joint association with SBP and PP. In conclusion, air pollutant co-exposure during adolescence may influence BP in young adulthood. The findings of this study emphasized the impacts of multiple air pollutants interactions on potential health and the need of minimizing pollution exposures in the environment.

Prevalence trends of hypertension and influence factors among children and adolescents aged 7-17 years in China, 2011-2015: A serial cross-sectional study

Hypertension has rapidly increased in the last decades throughout the world. It is an emerging disease. However, limited information is available on secular trends and factors of childhood and adolescents' hypertension in China. In this study, 5-year successive data were derived from a cross-sectional study of the China Health and Nutrition Survey (CHNS) in 2011 and 2015. We used systolic blood pressure (SBP) and/or diastolic blood pressure (DBP) at least 95th percentile on the basis of age, sex, and height percentiles to define hypertension (HBP). A total of 2,827 children and adolescents aged 7-17 years were included. The age-standardized prevalence of hypertension was increased significantly across 5 years: the standardized prevalence of hypertension was increased from 8.08% (2011) to 11.46% (2015) in China (P < 0.01). The mean SBP of boys increased from 101.21 to 102.79 mmHg, while the mean SBP of girls increased from 98.96 to 100.04 mmHg. The mean DBP of boys increased from 61.20 to 67.40 mmHg, while the mean DBP of girls increased from 64.34 to 65.76 mmHg. The prevalence of hypertension grew continuously in both sexes, but the pace of change for boys was more rapid than that for girls. This study confirmed that the association between rural (odds ratio [OR] = 1.394, 95%CI 1.032-1.883), overweight/obesity (OR = 2.621, 95%CI 1.506-4.562), and BP levels was highly correlated (P < 0.05). The possible protecting factors associated with hypertension were being a girl (OR = 0.788, 95%CI 0.595-1.043). There was no association between weekly physical activity, daily sleep duration, and hypertension (P > 0.05). Further in-depth analysis of influencing factors and comprehensive interventions should be urgently implemented to combat the hypertension epidemic among children and adolescents in China.

The associations between problematic smartphone use and blood pressure among 2,573 aged 9-17 years students in Shanghai, China

Objectives

This study aimed to (1) examine the cross-sectional association between problematic smartphone use (PSU) and blood pressure (BP) in children and adolescents and (2) determine whether the association between PSU and BP differs by the grade of students.

Methods

We recruited a total of 2,573 participants from 14 schools in Shanghai by a two-stage sampling method. We derived BP data from the participant's most recent medical examination data, including systolic blood pressure (SBP) and diastolic blood pressure (DBP). We measured PSU by a modified PSU Classification Scale. We also assessed demographic characteristics, body mass index, behavioral variables, and physiological characteristics.

Results

High school students had higher BP and PSU scores than primary and middle school students. PSU on the dimension of information collection was associated positively with both SBP and DBP among primary and middle school students, with the β (95% CI) values of 0.282 (0.018, 0.546) and 0.229 (0.031, 0.427). Meanwhile, the dimension of the relationship of social network was associated positively with SBP among primary and middle school students, with a β (95% CI) value of 0.390 (0.062, 0.717). PSU on the dimension of information collection was positively associated with the development of high BP, with a OR (95% CI) value of 1.072 (1.011, 1.137) among primary and middle school students.

Conclusions

PSU might be a potential correlate of high BP among school-age children and adolescents. The associations between PSU and BP differed by the grade of students as well as according to the four dimensions of PSU.

Prevalence of hypertension and hypertension phenotypes after three visits in Chinese urban children

OBJECTIVE

This study aims to evaluate the prevalence of hypertension and hypertension subtypes among Chinese children aged 6-17 years in a multicenter school-based sample by three separate screenings.

METHODS

Students from six major cities in China (Changchun, Beijing, Jinan, Shanghai, Chongqing, and Chengdu) were recruited in this cross-sectional survey during 2012 and 2015. Each participant was seated and had three consecutive blood pressure measurements on the right arm in the morning by an automated oscillometric device and the hypertensive ones were followed to the next visit. Hypertension was diagnosed by BP references for Chinese children and adolescents in 2010.

RESULTS

Data from 44 396 children aged 6-17 years were included in analysis, 50.9% of whom were boys. The prevalence of confirmed hypertension after three separate screenings was 4% in the total population, 5% in boys, and 3% in girls, respectively. The prevalence of confirmed isolated systolic hypertension (ISH), isolated diastolic hypertension (IDH), and systolic and diastolic hypertension (SDH) in the total population was 2.7, 0.3 and 1%, respectively.

CONCLUSION

Around 4% urban Chinese children and adolescents aged 6 -17 years were hypertensive after three separate BP screenings in 2012 -2015. ISH was the most frequent form of hypertension in children.

Secular trends in blood pressure trajectories in Chinese children and adolescents: the impact of changing physical growth

BACKGROUND

Globally, 80% of cardiovascular disease (CVD) occur in low-income /middle-income countries. High blood pressure (BP), a major risk factor for CVD, has its origins in early-life. We investigated how age trajectories of BP (childhood to late-adolescence) have changed recently in China and the mediating roles of physical growth.

METHODS

Using the longitudinal data on 3785 children from the China Health and Nutrition Survey 1991-2015, we estimated mean BP trajectories (7-18 years) for cohorts born in 1981-1985, 1986-1990, 1991-1995 and 1996-2000 using random effect models. Models were adjusted for BMI and/or height growth to assess their impact on BP trends.

RESULTS

BP trajectories shifted upwards across cohorts. Compared with the earliest cohort, mean BP was higher in the latest cohort throughout childhood to late adolescence. For example, the increment in SBP was 4.4 mmHg (95% confidence interval: 2.9-5.8) in boys and 4.0 mmHg (2.6-5.5) in girls at 9 years, narrowed slightly during adolescence, and was 3.0 mmHg (0.7-5.4) and 2.6 mmHg (0.4-4.8) respectively at 17 years. BMI and height trajectories also shifted upwards. The overall increment was greater for height than BMI. When adjusting for physical growth, the increment in BP trajectories reduced (more for height than BMI), but remained in childhood (P < 0.05).

CONCLUSION

The upward shift of BP trajectories among Chinese youths was largely explained by trends in physical growth, especially increasing height. Other early-life factors might have also contributed to the BP trends. Substantial increases in mean BP in children within a short time frame is a public health concern and will affect future CVD, especially in the developing world.

Does underweight amplify the relationship between short-term particulate matter exposure and blood pressure in children and adolescents: a large cross-sectional study in a metropolis of China

Overweight/obesity modified the effects of ambient particulate matter (PM) exposure on blood pressure (BP). This study aims to assess whether interaction of underweight and short-term PM exposure on BP exists in Chinese children. A cross-sectional analysis including 144,513 children aged 6 to 17 years in 2016 Health Promotion Program for Children and Adolescents of Suzhou, China, was performed. Daily concentrations of inhalable PM (PM₁₀) and fine PM (PM_2.5) were extracted from air monitoring stations close to students' schools. We applied generalized linear mixed-effects models to estimate the interactions. Estimated changes (95% confidence intervals (CIs)) of systolic BP (SBP), diastolic BP (DBP), and odds ratios (ORs) (95% CIs) for prevalence of HBP were calculated. Significant interactions between PM and underweight on BP and prevalence of high BP (HBP) were observed. For example, at lag 6, the ORs (95% CIs) for HBP by each 10 μg/m³ changes of PM_2.5 were 1.066 (1.039, 1.093) and 1.036 (1.028, 1.043) among underweight and normal weight subjects, respectively; these values for PM₁₀ were 1.048 (1.031, 1.065) and 1.025 (1.021, 1.030). At lag 5, the increases of SBP for PM_2.5 were 0.32 (95% CI 0.22, 0.43) mmHg and 0.23 (95% CI 0.29, 0.26) mmHg, while changes of DBP were 0.27 (95% CI 0.18, 0.35) mmHg and 0.19 (95% CI 0.16, 0.21) mmHg among underweight and normal weight subjects, respectively. Stratified analyses demonstrated that these interactions were only obtained in males. Effects of short-term PM exposure on BP and prevalence of HBP are enhanced in underweight children and adolescents.

Retinal Vessel Diameters and Blood Pressure Progression in Children

The prevalence of high childhood blood pressure (BP) is rising globally and has been associated with subclinical vascular impairments in children. Longitudinal data on the association of microvascular alterations with the development of high BP in children are lacking. We aimed to analyze the association of central retinal arteriolar (CRAE) and venular (CRVE) diameters with development of higher BP over 4 years in young school children. In 2014, 391 children aged 6 to 8 years were screened for BP and retinal vessel diameters using standardized protocols. Retinal vessel analysis was performed using a retinal vessel analyzer to determine CRAE and central retinal venular equivalent. In the follow-up of 2018, all parameters were assessed in 262 children using the same standardized protocols. During follow-up, systolic and diastolic BP increased significantly (Δ 3.965±8.25 and 1.733±7.63 mm Hg, respectively), while CRAE decreased by Δ -6.325±8.55 µm without significant changes in central retinal venular equivalent (Δ -0.163±7.94 µm). Children with narrower CRAE at baseline developed higher systolic BP after four years (β [95% CI] 0.78 [0.170-1.398] mm Hg per 10 µm decrease, P=0.012). Children with increased systolic or diastolic BP at baseline developed narrower CRAE (β [95% CI] -0.154 [-0.294 to -0.014] µm per 1mmHg, P=0.031 and β [95% CI] -0.02 [-0.344 to -0.057] µm per 1 mmHg, P=0.006, respectively) at follow-up. Narrowing of retinal arterioles predicted evolution of systolic BP. In turn, higher initial systolic and diastolic BP was associated with subsequent development of microvascular impairments. Our results give good evidence for a bivariate temporal relationship between BP and microvascular health in children.

Comparison of Trends in Blood Pressure and the Prevalence of Obesity Among Korean and American Adolescents: A 12-Years Cross-sectional Study

OBJECTIVES

This study was conducted to explore recent trends in the prevalence of pediatric elevated blood pressure and hypertension (HTN) in Korea and the United States, applying the new HTN reference values for adolescents.

METHODS

This study analyzed 17 339 (8755 Korean and 8584 American) adolescents aged 10 to 17 who participated in the Korea National Health and Nutrition Examination Survey and the National Health and Nutrition Examination Survey, respectively, between 2005 and 2016. HTN was defined using percentile-based reference values for non-overweight adolescents from 7 nations, and obesity was defined by body mass index (BMI) based on country-specific growth charts. All analyses were stratified by sex and year-over-year changes were evaluated by calculating the p for trend.

RESULTS

Systolic blood pressure showed a statistically meaningful upward trend in Korean boys and girls, while diastolic blood pressure did not show any significant changes. Both systolic and diastolic blood pressure levels declined among United States boys and girls. The prevalence of elevated blood pressure and HTN remained similar in Korean adolescents, but declined in both sexes among United States adolescents. BMI increased in both sexes among Korean adolescents, although the overweight and obesity rates stayed the same. No significant trends were found in any obesity indices among United States adolescents. The prevalence of elevated blood pressure and HTN by obesity level was higher among Korean adolescents than among their United States peers in both sexes, and the gap became higher at more severe levels of obesity.

CONCLUSIONS

Despite the strong correlation between obesity and HTN, recent trends in the prevalence of HTN and obesity among Korean and United States adolescents were strikingly different. Follow-up studies are necessary to determine why the prevalence of HTN was more than twice as high among Korean adolescents than among their United States counterparts.

Nutrition Education Practices of Health Teachers from Shanghai K-12 Schools: The Current Status, Barriers and Willingness to Teach

China is facing challenges in both undernutrition and overnutrition, resulting from unhealthy diets. Nutrition education early in life, especially in school settings, has been reported to be effective in addressing these challenges. However, little is known about how nutrition education is delivered in schools in China. This study aimed to investigate the current status of delivering nutrition education by health teachers in Shanghai and to determine the barriers and resources that influence the teachers’ practices and their willingness to teach nutrition. In 2016–2017, a cross-sectional questionnaire survey was conducted on 904 health teachers from 823 K-12 schools in Shanghai, China. There were 722 (79.9%) teachers that had the experience of teaching nutrition, but only 137 (19.0% of 722) spent ≥1 h teaching nutrition courses in each school year. Only 18.6% of the teachers had received a formal education in nutrition in college. About 88.5% of teachers expressed their willingness to teach nutrition in the future. The three major reasons for never teaching nutrition were categorized as: nutrition being taught by other teachers (39.5%), willing to teach but lack of knowledge (37.9%), and the subject not being required by school administrators (31.3%). Teachers who spent more time or were more willing to teach nutrition courses were those who were female, from private schools, had a better background in receiving nutrition education, and were more concerned about nutrition. Our data show that nutrition education is at a formative stage in Shanghai, China.

Antihypertensive drugs use over a 5-year period among children and adolescents in Beijing, China: An observational study

Evidence on the prescription patterns of antihypertensive drug use in children and adolescents in China is scarce. A descriptive analysis of the Beijing Medical Claim Data, which covered over 95% of the urban residents, was conducted to investigate antihypertensive prescribing patterns and trends in children and adolescents aged under 18 from 2009 to 2014 in Beijing, China. An additional meta-analysis of trends in hypertension prevalence was conducted to compare trends with antihypertensive medications.A total of 11,882 patients received at least 1 prescription for antihypertensive drugs from 2009 to 2014. The number of annual antihypertensive users increased from 2009 to 2012, then declined steadily until 2014, which was consistent with the trend of the hypertension prevalence estimated from the meta-analysis. β-receptor blockers, thiazide diuretics, and angiotensin-converting enzyme inhibitors were the 3 most commonly prescribed antihypertensive drugs. More boys took the antihypertensive drugs than girls. For users aged under 3 years, thiazide diuretics, α-receptor blockers, and angiotensin-converting enzyme inhibitors were the most prescribed drugs, while β-receptor blockers, thiazide diuretics were the most used drugs for users above 3 years.In conclusion, antihypertensive drug prescribing for children and adolescents increased from 2009 to 2014, with different characteristics in different subgroups.

Parental overweight and hypertension are associated with their children's blood pressure

Background

We evaluated the association between parental factors (overweight, history of hypertension, and education level) and children’s blood pressure status. Further, we evaluated to what extent the potential association could be interpreted by children’s adiposity indices.

Methods

The current study included 3316 Chinese school students (1579 girls and 1737 boys, aged 6–14 years) and their parents. Parents reported information on their height, body weight, history of hypertension, and the highest education level. Trained medical staff measured children’s blood pressure, height, body weight, waist circumference (WC), and percentage of body fat (PBF, assessed by bio-impedance method). Z-score of all three indices were calculated and used in the analysis. We used generalized linear model to evaluate the association between parental information and z-score of children’s blood pressure. Meditation analysis was used to evaluate the proportion contributed by z-score of children’s adiposity indices (BMI, WC, and PBF).

Results

We found that parental overweight and hypertension, but not parental education level, were significantly associated with children’s systolic and diastolic blood pressure (P < 0.05 for all). Approximately 30.4–92.2% of the association between these two parental factors and children’s systolic blood pressure were mediated by children’s adiposity indices, and 22.3–55.6% for children’s diastolic blood pressure. The strongest meditative factor, among the three obesity indices, was children’s BMI z-score.

Conclusions

The association between parental factors and children’s blood pressure was mainly mediated by children’s adiposity indices.

Electronic supplementary material

The online version of this article (10.1186/s12986-019-0357-4) contains supplementary material, which is available to authorized users.

Prevalence of high blood pressure and high normal blood pressure among 7- to 17-year-old children and adolescents in developed regions, China from 2014 to 2017: using new national blood pressure reference for Chinese children and adolescents

As the first blood pressure (BP) reference considering influence of height in China, national blood pressure reference for Chinese han children and adolescents aged 7 to 17 years (CCBP) was issued in 2017. The current study aimed to observe the short-term trends in BP and prevalence of high blood pressure (HBP) and high normal blood pressure (HNBP) using this CCBP reference in Suzhou, China. Data of children and adolescents aged 7 to 17 years were collected from 2014 to 2017. Total population of 2014 to 2017 were 617,383, 684,453, 695,302, and 774,605, respectively, and proportions of males were 54.1%, 54.0%, 53.9%, and 53.8%, respectively. P-trend tests were conducted to examine the trends of BP among different age, region, body mass index, and socioeconomic status groups for each gender. Multivariate logistic regression analyses found secular decreases in prevalence of HBP and HNBP, after adjustment for potential confounders. Compared with that in 2014, the odds ratios (95% confidence intervals) for total study population were 0.936 (0.928, 0.944) in 2015, 0.879 (0.872, 0.887) in 2016, and 0.934 (0.926, 0.941) in 2017. In conclusion, prevalence of HBP and HNBP decreased among children and adolescents in developed regions of China from 2014 to 2017, and a slight rise were found in 2017.

Cardiovascular health in urban Chinese children and adolescents

INTRODUCTION

Cardiovascular diseases remain the leading cause of death and disease burden in China and worldwide. We aimed to evaluate the status of cardiovascular health among urban Chinese children and adolescents.

METHODS

We conducted a cross-sectional study comprising 12,618 children and adolescents aged 6-18 years, who were recruited from Chinese urban areas during 2013-2015. The poor, intermediate, and ideal levels of 7 cardiovascular health metrics, including smoking, body mass index, dietary intake, physical activity, blood pressure, blood glucose, and total cholesterol were defined according to revised American Heart Association criteria.

RESULTS

Ideal smoking status was the most prevalent health component (overall, 90.7%; males, 86.3% and females, 95.4%), whereas ideal health diet score (overall, 8.7%; males, 9.1% and females, 8.3%) was the least prevalent among urban Chinese children and adolescents. The majority (overall, 84.9%; males, 82.6% and females, 87.4%) of participants had 3-5 ideal metrics. The overall prevalence of ideal cardiovascular health (i.e. meeting all 7 ideal components) was extremely low (overall, 0.5%; males, 0.5% and females, 0.4%).

CONCLUSIONS

The prevalence of ideal cardiovascular health in urban Chinese children and adolescents is extremely low, particularly for physical activity and healthy dietary intake. Effective public health interventions are required to improve cardiovascular health in children and adolescents to reduce future cardiovascular risk. Key messages Ideal health diet score was the least prevalent health component among urban Chinese children and adolescents The prevalence of ideal cardiovascular health in urban Chinese children and adolescents was extremely low Effective public health interventions are required to improve cardiovascular health in children and adolescents to reduce future cardiovascular risk.

Differences in prevalence of prehypertension and hypertension in children and adolescents in the eastern, central and western regions of China from 1991-2011 and the associated risk factors

The present study aimed to estimate the differences in rates of prehypertension and hypertension in children and adolescents among three regions with different socioeconomic status in China, and explore the corresponding risk factors associated with prehypertension and hypertension to guide the prevention. Blood pressure measurements of 13 762 children and adolescents aged 6–17 years were obtained from a prospective national survey (the China Health and Nutrition Survey, 1991–2011). Prehypertension and hypertension were defined by age and gender, according to China’s standard criteria. Chi-square tests were used to compare the differences in the prevalence of prehypertension and hypertension among three regions. Trend chi-square tests were used to detect the trends in rates of prehypertension and hypertension over survey years. Logistic regression models were used to detect the potential risk factors of prehypertension and hypertension in children and adolescents. During the survey years, the overall prevalence of prehypertension and hypertension were 6.0% and 10.6%. The corresponding rates in the western region were lowest, but increased rapidly over the two decades (84.0% and 122.6% increases respectively, P<0.001). The overall hypertension rate remained high in the eastern region, despite the slower increase (24.2% increase). In the central region, although the prehypertension rate remained stable, the rate of hypertension had a 94.8% increase these years (P<0.0001). According to the results of logistic regression, age, body mass index (BMI) and waist/height ratio (WHtR) were associated with prehypertension and hypertension. Children and adolescents in the eastern region had the highest level of prehypertension and hypertension, while the rapid increase of blood pressure in the western and central regions were also supposed to concern. Improvement of the healthy lifestyle is urgent for prehypertension and hypertension prevention in children and adolescents.

Effects of resting heart rate on blood pressure and hypertension in Chinese children: findings from blood pressure surveillance program

The purpose of this study was to analyze the association between resting heart rate (RHR) and prevalence of hypertension in Chinese children and to identify if this association was mediated by body mass index (BMI). The data of 5445 children who participated in the Blood Pressure Surveillance Program (2011-2017) were analyzed in this study. Children were divided into four groups according to quartiles of RHR in boys and girls, respectively. Compared to those in the first quartile, boys and girls in the fourth quartile were 3.06 (95% CI 2.12, 4.41) and 4.94 (95% CI 3.21, 7.61) times more likely to have hypertension, respectively. Meanwhile, every 10 beats per minute (bpm) increase in RHR was associated with a 41% (95% CI 1.27, 1.56) and 66% (95% CI 1.49, 1.85) greater risk of hypertension in boys and girls, respectively. There were no significant interactions between RHR and BMI on the prevalence of hypertension. This study confirms the existence of a relationship between elevated RHR and increased risk of hypertension in children, independent of BMI. An elevated RHR could be considered as a risk factor for the risk assessment of hypertension, no matter from a clinical setting or a public health perspective.

Associations between general and central obesity and hypertension among children: The Childhood Obesity Study in China Mega-Cities

In this study, we examined the associations of general and central obesity and hypertension among Chinese children. Data was collected from 1626 children aged 7-16 years and their parents in four mega-cities across China. Mixed effect models examined associations of general and central obesity with hypertension, and between body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR), systolic blood pressure (SBP) and diastolic blood pressure (DBP). The prevalence of general obesity, central obesity, and hypertension among the children was 11.1%, 19.7%, and 9.0%, respectively. More boys had general and central obesity than girls (15.2% vs. 6.9%; 27.4% vs. 11.7%, respectively; both P < 0.0001). Sex difference in hypertension rate was not statistically significant (9.3% in boys vs. 8.8% in girls, P = 0.7341). Both SBP and DBP were positively associated with BMI, WC, and WHtR, regardless of sex and region. General obesity (OR = 5.94, 95% confidence interval [CI]: 3.69-9.55) and central obesity (OR = 3.45, 95% CI: 2.27-5.23) were strongly associated with hypertension. The prevalence of general obesity, central obesity, and hypertension was high among Chinese children in the four mega-cities across China. Children's BMI, WC, and WHtR were positively associated with their SBP and DBP. Obese children were 3-6 times more likely to have hypertension.

Elevated blood pressure is associated with higher prevalence of low visual acuity among adolescent males in Northeast China

The purpose of this study is to track the trends of low visual acuity (VA) from 2005 to 2014, and to investigate its associations with systemic blood pressure (BP) components among adolescents in Northeast China. A total of 55320 students of Han nationality aged 13 to 18 years were included. There has been a significant increase in the prevalence of low VA, with 31.3% in 2005, 40.2% in 2010 and 43.4% in 2014. In multivariable-adjusted logistic regression models, each 1-mm Hg increment in systolic BP (SBP) was associated with 0.8% (95% confidence interval [CI]: 0.1–1.6%), 0.5% (95% CI: 0.1–0.9%) and 1.1% (95% CI: 0.6–1.6%) increased odds of low VA for males in 2005, 2010 and 2014; each 1-mm Hg increment in pulse pressure (PP) was associated with 1.6% (95% CI: 0.7–2.5%), 0.8% (95% CI: 0.4–1.2%) and 1.2% (95% CI: 0.7–1.7%) increased odds of low VA. Higher PP categories had greater odds for low VA compared with the reference group. Similar associations were not observed for females. We conclude that higher prevalence of low VA was significantly associated with higher SBP and PP in males. Furthermore, there was a dose-dependent association between the prevalence of low VA and the levels of PP.

Primary Pediatric Hypertension: Current Understanding and Emerging Concepts

The rising prevalence of primary pediatric hypertension and its tracking into adult hypertension point to the importance of determining its pathogenesis to gain insights into its current and emerging management. Considering that the intricate control of BP is governed by a myriad of anatomical, molecular biological, biochemical, and physiological systems, multiple genes are likely to influence an individual's BP and susceptibility to develop hypertension. The long-term regulation of BP rests on renal and non-renal mechanisms. One renal mechanism relates to sodium transport. The impaired renal sodium handling in primary hypertension and salt sensitivity may be caused by aberrant counter-regulatory natriuretic and anti-natriuretic pathways. The sympathetic nervous and renin-angiotensin-aldosterone systems are examples of antinatriuretic pathways. An important counter-regulatory natriuretic pathway is afforded by the renal autocrine/paracrine dopamine system, aberrations of which are involved in the pathogenesis of hypertension, including that associated with obesity. We present updates on the complex interactions of these two systems with dietary salt intake in relation to obesity, insulin resistance, inflammation, and oxidative stress. We review how insults during pregnancy such as maternal and paternal malnutrition, glucocorticoid exposure, infection, placental insufficiency, and treatments during the neonatal period have long-lasting effects in the regulation of renal function and BP. Moreover, these effects have sex differences. There is a need for early diagnosis, frequent monitoring, and timely management due to increasing evidence of premature target organ damage. Large controlled studies are needed to evaluate the long-term consequences of the treatment of elevated BP during childhood, especially to establish the validity of the current definition and treatment of pediatric hypertension.

Endothelial Dysfunction in Children With Obstructive Sleep Apnea Is Associated With Elevated Lipoprotein-Associated Phospholipase A2 Plasma Activity Levels

BACKGROUND

Obstructive sleep apnea (OSA) is a highly prevalent condition, especially in obese children, and has been associated with increased risk for endothelial dysfunction and dislipidemia, which are precursors of atherosclerosis. Lipoprotein-associated phospholipase A2 (Lp-PLA2) is recognized as an independent risk factor for cardiovascular risk and atheromatous plaque activity. We hypothesized that Lp-PLA2 levels would be elevated in children with OSA, particularly among obese children who also manifest evidence of endothelial dysfunction.

METHODS AND RESULTS

One hundred sixty children (mean age 7.1±2.3 years), either nonobese with (n=40) and without OSA (n=40) or obese with (n=40) and without OSA (n=40) underwent overnight polysomnographic and postocclusive reperfusion evaluation and a fasting blood draw the morning after the sleep study. In addition to lipid profile, Lp-PLA2 plasma activity was assessed using a commercial kit. Obese children and OSA children had significantly elevated plasma Lp-PLA2 activity levels compared to controls. Furthermore, when both obesity and OSA were concurrently present or when endothelial function was present, Lp-PLA2 activity was higher. Treatment of OSA by adenotonsillectomy resulted in reductions of Lp-PLA2 activity (n=37; P<0.001).

CONCLUSIONS

Lp-PLA2 plasma activity is increased in pediatric OSA and obesity, particularly when endothelial dysfunction is present, and exhibits decreases on OSA treatment. The short-term and long-term significance of these findings in relation to cardiovascular risk remain undefined.