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 (PM2.5) 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 PM2.5 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 PM2.5 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.

Short-term effects of ambient particulate matter on blood pressure among children and adolescents:A cross-sectional study in a city of Yangtze River delta, China.

Several studies have demonstrated associations between short-term exposure to particulate matter (PM) and blood pressure (BP) among various adults groups, but evidence in children and adolescents is still rare. In 2016, a cross-sectional survey was conducted among 194 104 participants aged 6-17 years in Suzhou, China. Daily concentrations of particulate matters with an aerodynamic diameter of ≤10 µg/m3 (PM10) and aerodynamic diameter ≤2.5 µg/m3 (PM2.5) on 0-6 days preceding BP examination were collected from nearby air monitoring stations. Using generalized linear mixed-effects models, short-term effects of PM on personal BP were estimated. A 10 µg/m3 increment in the 0-6 day mean of PM2.5 was significantly associated with elevation of 0.20 mmHg [95% confidence interval (95% CI) 0.16-0.23] in systolic BP (SBP), 0.49 mmHg (95% CI 0.45-0.53) in diastolic BP (DBP), respectively. Similarly, 0.14 mmHg (95% CI 0.12-0.16) higher SBP and 0.32 mmHg (95% CI 0.30-0.34) higher DBP were found for each 10 µg/m3 increase in 0-6 day mean of PM10. More apparent associations were observed in females than in males. Odds ratio (95%CI) of for PM2.5 exposure at 0-6 d mean was 1.06 (1.03-1.08) in females, while it was 1.01 (0.99-1.03) in males. Participants with young ages, underweight and obesity were also associated with increased susceptibility to PM-induced BP effects. Short-term exposure in PM was significantly associated with elevated BP in children, indicating a need to control PM levels and protect children from PM exposure in China.

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.

The short-term effects of outdoor temperature on blood pressure among children and adolescents: finding from a large sample cross-sectional study in Suzhou, China.

Although several studies have demonstrated a short-term association between outdoor temperature and blood pressure (BP) among various adult groups, evidence among children and adolescents is lacking. One hundred ninety-four thousand one hundred four participants from 2016 Health Promotion Program for Children and Adolescents (HPPCA) were analyzed through generalized linear mixed-effects models to estimate the short-term effects of two outdoor temperature variables (average and minimum temperature) on participants' BP. Decreasing outdoor temperature was associated with significant increases in systolic BP (SBP), diastolic BP (DBP), and prevalence of hypertension during lag 0 through lag 6. Additionally, daily minimum temperature showed a more apparent association with participants' BP. The estimated increases (95% confidence interval) in SBP and DBP at lag 0 were 0.82 (0.72, 0.92) mmHg and 2.28 (2.20, 2.35) mmHg for a 1 °C decrease in daily minimum temperature, while those values were 0.11 (0.10, 0.12) mmHg and 0.25 (0.24, 0.26) mmHg for a 1 °C decrease in daily average temperature, respectively. The effects of temperature on BP were stronger among female, as well as those with young age and low body mass index. It demonstrated that short-term decreases in outdoor temperature were significantly associated with rises in BP among children and adolescents. This founding has some implications for clinical management and research of BP. Meanwhile, public health intervention should be designed to reduce the exposure to cold temperature for protecting children and adolescents' BP.

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.

Association of elevated resting pulse rate with increased risk of hypertension development in children: A prospective study in Suzhou, China.

BACKGROUND: Elevated resting heart rate (RHR) or resting pulse rate (RPR) is associated with increased risk of hypertension development. However, information is limited to adults. The purpose of this study is to analyze this association among Chinese children in a prospective design. METHODS: A total of 4861 children who participated in the Blood Pressure Surveillance Program (2011-2017) were selected in this research. To investigate the association between RPR and hypertension development, children were divided into 4 groups according to the quartiles of RPR at baseline. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using logistic regression model. RESULTS: Over a mean follow-up of 3.0 ±â€Š0.1 years, there were 384 cases of incident hypertension. Compared to boys and girls in the 1st quartile, those in the 4th quartile were 1.73 (95% CI 1.13, 2.65), 2.22 (95% CI 1.43, 3.45) times more likely to have hypertension, respectively. Every 10 bpm increase in RPR was associated with a 26% greater risk of hypertension development in boys (OR: 1.26; 95% CI 1.10, 1.44), while this risk was 1.28 (95% CI 1.13, 1.44) in girls. Baseline blood pressure (BP) and body mass index (BMI) did not have significant interactions with RPR on risk of hypertension development. CONCLUSION: This study confirms the relationship between elevated RPR and increased risk of hypertension development in children, independent of confounders including baseline BP and BMI. An elevated RPR could be considered as a risk factor for the assessment of hypertension, no matter from a clinical setting or a public health perspective.

Relation of body mass index (BMI) to the prevalence of hypertension in children: A 3years' school-based prospective study in Suzhou, China.

BACKGROUND: The prevalence of hypertension has been increasing in children and adolescents in China, which is considered to be accompanied with the epidemic of childhood overweight and obesity, but limited prospective studies have investigated the effect of body mass index (BMI) change on blood pressure among children, especially in China. METHODS: This school-based prospective study compared the blood pressure and prevalence of hypertension in students with different patterns of change in BMI between two periods (childhood and adolescence). 5465 children were followed-up since 2011(childhood) in Suzhou, China and had weight, height and blood pressure measured in 2011(childhood) and 2014(adolescence). RESULTS: Those who changed from being overweight in childhood to having normal BMI in adolescence had similar mean blood pressures to those who had a normal BMI at both two periods. In contrast, those who were overweight at both two periods or who had a normal BMI in childhood and were overweight in adolescence had higher blood pressure in adolescence than those who had a normal BMI at both two periods. Compared with students who had a normal BMI at both periods, those with combination of abnormal BMI in childhood and adolescence have higher ORs of hypertension (4.83 in boys, 3.44 in girls and 3.73 in total). CONCLUSION: These results suggest that obesity is a key determinant of blood pressure during childhood, and weight reduction may have important beneficial effects on blood pressure.

A family cluster of nitrite poisoning, Suzhou City, Jiangsu Province, China, 2013.

BACKGROUND: In April 2013, a hospital in Suzhou City notified authorities of a patient with nitrite poisoning with two other family members who had similar toxic symptoms five days prior. We investigated the event to identify the cause, source and possible route of contamination. METHODS: A case was defined as any person living in the Yang Shan Hua Yuan community who had been diagnosed with cyanoderma and food poisoning symptoms from 15 to 25 April 2013. Active case finding was conducted by interviewing community residents and reviewing medical records from local clinics; information was then retrospectively collected on the patient's food history, cooking procedures and food sources. RESULTS: We identified three nitrite poisoning cases, one male and two females, from the same family. The time between dinner and onset of illness was less than an a hour. A retrospective survey showed that a substance presumed to be sugar mixed with asparagus on 17 April and with stir-fried asparagus on 21 April was the suspected contaminant. The presumed sugar came from a clean-up of a neighbouring rental house. Nitrite was detected in a vomitus sample, the sugar substance and two leftover food samples. CONCLUSION: This family cluster of nitrite poisoning resulted from the mistaken use of nitrite as sugar to cook dishes. We recommend that sodium nitrite be dyed a bright colour to prevent such a mistake and that health departments strengthen food hygiene education to alert people about the danger of eating unidentified food from an unknown source.

A family cluster of nitrite poisoning, Suzhou City, Jiangsu Province, China, 2013

Background：In April 2013, a hospital in Suzhou City notified authorities of a patient with nitrite poisoning with two other family members who had similar toxic symptoms five days prior. We investigated the event to identify the cause, source and possible route of contamination.Methods：A case was defined as any person living in the Yang Shan Hua Yuan community who had been diagnosed with cyanoderma and food poisoning symptoms from 15 to 25 April 2013. Active case finding was conducted by interviewing community residents and reviewing medical records from local clinics; information was then retrospectively collected on the patient’s food history, cooking procedures and food sources.Results：We identified three nitrite poisoning cases, one male and two females, from the same family. The time between dinner and onset of illness was less than an a hour. A retrospective survey showed that a substance presumed to be sugar mixed with asparagus on 17 April and with stir-fried asparagus on 21 April was the suspected contaminant. The presumed sugar came from a clean-up of a neighbouring rental house. Nitrite was detected in a vomitus sample, the sugar substance and two leftover food samples.Conclusion：This family cluster of nitrite poisoning resulted from the mistaken use of nitrite as sugar to cook dishes. We recommend that sodium nitrite be dyed a bright colour to prevent such a mistake and that health departments strengthen food hygiene education to alert people about the danger of eating unidentified food from an unknown source.