Urban-rural disparity in blood pressure among Chinese children: 1985-2010

Prevalence of childhood hypertension and associated factors in Zhejiang Province: a cross-sectional analysis based on random forest model and logistic regression

With childhood hypertension emerging as a global public health concern, understanding its associated factors is crucial. This study investigated the prevalence and associated factors of hypertension among Chinese children. This cross-sectional investigation was conducted in Pinghu, Zhejiang province, involving 2,373 children aged 8-14 years from 12 schools. Anthropometric measurements were taken by trained staff. Blood pressure (BP) was measured in three separate occasions, with an interval of at least two weeks. Childhood hypertension was defined as systolic blood pressure (SBP) and/or diastolic blood pressure (DBP) ≥ age-, sex-, and height-specific 95th percentile, across all three visits. A self-administered questionnaire was utilized to collect demographic, socioeconomic, health behavioral, and parental information at the first visit of BP measurement. Random forest (RF) and multivariable logistic regression model were used collectively to identify associated factors. Additionally, population attributable fractions (PAFs) were calculated. The prevalence of childhood hypertension was 5.0% (95% confidence interval [CI]: 4.1-5.9%). Children with body mass index (BMI) ≥ 85th percentile were grouped into abnormal weight, and those with waist circumference (WC) > 90th percentile were sorted into central obesity. Normal weight with central obesity (NWCO, adjusted odds ratio [aOR] = 5.04, 95% CI: 1.96-12.98), abnormal weight with no central obesity (AWNCO, aOR = 4.60, 95% CI: 2.57-8.21), and abnormal weight with central obesity (AWCO, aOR = 9.94, 95% CI: 6.06-16.32) were associated with an increased risk of childhood hypertension. Childhood hypertension was attributable to AWCO mostly (PAF: 0.64, 95% CI: 0.50-0.75), followed by AWNCO (PAF: 0.34, 95% CI: 0.19-0.51), and NWCO (PAF: 0.13, 95% CI: 0.03-0.30). Our results indicated that obesity phenotype is associated with childhood hypertension, and the role of weight management could serve as potential target for intervention.

Reference blood pressure values obtained using the auscultation method for 2-year-old Japanese children: from the Japan Environment and Children's Study

BACKGROUND

Reference blood pressure (BP) values for Japanese children based on a large number of measurements by auscultation have not yet been established.

METHODS

This was a cross-sectional analysis of data from a birth-cohort study. The data from the sub-cohort study conducted for children at the age of 2 years in the Japan Environment and Children's Study from April 2015 to January 2017 were analyzed. BP was measured via auscultation using an aneroid sphygmomanometer. Each participant was measured in triplicate, and the average value of two consecutive measurements with a difference of less than 5 mmHg was recorded. The reference BP values were estimated using the lambda-mu-sigma (LMS) method and compared with those obtained via the polynomial regression model.

RESULTS

Data from 3361 participants were analyzed. Although the difference between the estimated BP values by the LMS and the polynomial regression model was small, the LMS model was more valid based on the results of the fit curve of the observed values and regression models for each model. For 2-year-old children with heights in the 50th percentile, the 50th, 90th, 95th, and 99th percentile reference values of systolic BP (mmHg) for boys were 91, 102, 106, and 112, and that for girls were 90, 101, 103, and 109, respectively, and those of diastolic BP for boys were 52, 62, 65, and 71, and that for girls were 52, 62, 65, and 71, respectively.

CONCLUSION

The reference BP values for 2-year-old Japanese children were determined based on auscultation and were made available.

Children who appeared or remained overweight or obese predict a higher follow-up blood pressure and higher risk of hypertension: a 6-year longitudinal study in Yantai, China

Few longitudinal studies have examined the effect of weight status change on blood pressure change over time and incidence of hypertension among Chinese children. The longitudinal study enrolled 17,702 Chinese children aged 7 years in Yantai in 2014 as baseline, with a continuous 5 years of follow-up to 2019. Generalized estimating equation model was fitted to examine the main and interaction effects of weight status change and time with blood pressure and the incidence of hypertension. Compared with the participants who remained normal weight, the participants who remained overweight or obese had higher systolic blood pressure (SBP) (β = 2.89, p < 0.001) and diastolic blood pressure (DBP) (β = 1.79, p < 0.001). Significant interactions were identified between weight status change and time with SBP (χ2interaction = 697.77, p < 0.001) and DBP (χ2interaction = 270.49, p < 0.001). The odds ratio (OR) and 95% confidence interval (CI) of hypertension were 1.70 (1.59-1.82) for participants who appeared overweight or obese, 2.26 (2.14-2.40) for participants who remained overweight or obese, compared with the participants who remained normal weight. Those who switched from overweight or obesity to normal weight had almost the same risk of developing hypertension (OR = 1.13, 95% CI: 1.02 to 1.26) as children who remained normal weight. Children who appeared or remained overweight or obese predict a higher follow-up blood pressure and higher risk of hypertension, whereas losing weight could reduce blood pressure and the risk of hypertension. Children who appeared or remained overweight or obese predict a higher follow-up blood pressure and higher risk of hypertension, whereas losing weight could reduce blood pressure and the risk of hypertension.

Trends in associations between socioeconomic development and urban-rural disparity with high blood pressure in Chinese children and adolescents over two decades

This study aimed to assess the association between the trend of urban-rural disparity in high blood pressure (HBP) in Chinese children and adolescents and socioeconomic development. Data on 1,054,602 students aged 7-18 years were obtained from five successive national surveys administered in 29 Chinese provinces in 1995, 2000, 2005, 2010, and 2014. HBP was defined as average measured systolic BP and/or diastolic BP equal to or more than 95th percentile. The socioeconomic indicators at the provincial-level included gross domestic product (GDP) per capita, the Engel coefficient, and urbanization rates. From 1995 to 2014, HBP prevalence in Chinese children and adolescents fluctuated between 6.9% and 9.2%. Rural areas had a higher prevalence of HBP than urban areas, with a diminishing trend in urban-rural disparity from 1995 to 2010 with a reduced OR from 1.45 (95% CI: 1.40-150) in 1995 to 1.09 (1.05-1.12) in 2010, whereas a widening gap in 2014 with OR of 1.23 (1.19-1.26)). A positive association existed between the improvement of socioeconomic indicators and the increase in HBP, which was demonstrated obviously by the Engel coefficient strata. The increases in the urbanization rates were accompanied by a greater increase of HBP in urban than in rural areas. The large urban-rural disparity suggests a priority of HBP control in rural children due to their current and future HBP and cardiovascular disease risks. Socioeconomic development could affect the urban-rural disparity in HBP risk, reflecting the importance of effective policy responses for preventing HBP by avoiding unhealthy lifestyles brought about by rapid economic development.

Prevalence trends of hypertension among 9-17 aged children and adolescents in Yunnan, 2017-2019: a serial cross-sectional surveillance survey

BACKGROUND

We aim to describe the prevalence and trends of hypertension among 9-17 school-aged students from 2017 to 2019 in Yunnan, China.

METHODS

We conducted a cross-sectional study by using data from the Students' Health Surveillance Surveys of 2017, 2018 and 2019 in Yunnan. The Students' Health Surveillance Surveys in Yunnan collected date on physical fitness and health status of students in Yunnan through multistage-stratified sampling in 3 prefectures. In each prefecture, the study population were classified by gender and region (urban or rural), and each group had an equal size. Diagnosing criteria of hypertension was set with reference to Chinese age-specific and height-specific blood pressure (BP), to identify the abnormal status of boys and girls separately. ANOVA test was adopted to measure the differences in the mean BP stratified by gender, age, prefecture and area, and Chi-square test was used to compare the percentages of hypertension in different areas. For comparability, the age-standard and gender-standard population prevalence was calculated by directly using China Census in 2010 as a standard population. Totally 24,890 participants aged 9-17 years were included in this study.

RESULTS

From 2017 to 2019, there were 24,872 students completed physical examinations and included in the analysis, of which 3288 were diagnosed with hypertension. The total prevalence of hypertension was 13.72, 12.49 and 13.45% among 9-17 years school-aged population in Yunnan, respectively. The total age-standardized hypertension prevalence trended to decrease from 13.82 to 13.48%. For urban population, the age-standardized hypertension prevalence decreased slightly from 11.24 to 10.13%. While, for rural population, it increased from 17.58 to 19.16%. The average annual growth rate in rural population was 0.53%.

CONCLUSIONS

From 2017to 2019, there was a significant and continuous increase in the prevalence of hypertension in 9-17 years school-aged population in Yunnan. Hypertension is epidemic among children and adolescents in Yunnan. We should take effective and comprehensive intervention measures to reduce its prevalence among school-aged children.

Prevalence and Risk Factors of Childhood Hypertension in Urban-Rural Areas of China: A Cross-Sectional Study

OBJECTIVE

The increased blood pressure level in children and adolescents is recognized as an essential predictor of adulthood cardiovascular disease. This study aimed to ascertain the prevalence and the urban-rural disparity of childhood hypertension in the southwest of China.

METHODS

Using stratified cluster sampling in urban and rural areas, a total of 13597 primary school children aged 6∼12 years living in the Southwest of China were included. The prevalence of hypertension was analyzed. The risk factors were collected by questionnaires, and the risk factors of childhood hypertension were analyzed by the logistic regression model.

RESULTS

The prevalence of hypertension was 13.75%, 9.02%, and 17.47% in total, urban, and rural children, respectively, and the urban-rural difference was 8.44% (95%CI: 7.32%, 9.56%). Children with obesity, maternal gestational hypertension, >10 months of breastfeeding, or low family income had a significantly increased prevalence of hypertension (29.4%, 20.00%, 16.31%, and 16.25%, respectively). Rural residence, intake of more pickle (in rural), maternal gestational hypertension (in urban), low birth weight (in rural), obesity, increased heart rate, and red blood cell counts were the risk factors of childhood hypertension. The adjusted R ² values were 13.61%, 23.25%, 10.88%, 11.12%, 12.23%, and 25.04% in the full models excluding and including serum indexes for total, urban, and rural children, respectively.

CONCLUSIONS

The prevalence of childhood hypertension is significant in the Southwest of China and alarming in rural areas, which requires community intervention. Children living in rural areas combined with obesity, low social economic status, dietary imbalance, and abnormal lipid metabolism were associated with an increased risk of hypertension, and routine care programs should be conducted to prevent childhood hypertension.

National trends of pre-hypertension and hypertension among Iranian adolescents across urban and rural areas (2007-2011)

BACKGROUND

The current nationwide study, for the first time, aimed to assess and compare the trend of pre-hypertension and hypertension among urban and rural adolescents in Iran.

METHODS

This study has been conducted in the framework of the National Surveys of Risk Factors for Non-Communicable Diseases. To estimate pre-hypertension and hypertension prevalence among 9715 adolescents, aged 15-19 years, data collected in four repeated cross-sectional surveys (2007-2011) has been used. The prevalence trends of pre-hypertension and hypertension were examined across urban and rural areas of Iran. To calculate the adjusted prevalence ratios (PRs) of pre-hypertension and hypertension over cycles across area of residence and genders, a complex sample survey and multinomial logistic analysis were performed.

RESULTS

Using the definition of pre-hypertension and hypertension presented by the seventh Joint National Committee (JNC-VII) for adolescents, after adjusting for confounders, the prevalence of pre-hypertension changed in both urban (boys:28.96% to 29.24% and girls:18.33% to 20.06%) and rural (boys 31.58% to 32.05% and girls 22.25% to 24.13%) areas over the study duration. Non-significant rising prevalence of hypertension was also observed in boys and girls of both regions (urban 12.76% to 15.04% and 8.02% to 9.06%; rural 9.95% to 11.79% and 10.35% to 11.60%, for boys and girls respectively). The adjusted prevalence ratios (PRs) of pre-hypertension (2.16; 95% CI 1.68-2.79 and 1.92, 95% CI 1.57-2.34, in urban and rural, respectively) and hypertension (2.40; 95% CI 1.65-3.51 and 1.82, 95% CI 1.36-2.45, in urban and rural, respectively) were higher in boys than girls. Comparing the adjusted PRs of pre-hypertension and hypertension in urban versus rural areas, in both genders, showed higher PRs of pre-hypertension in rural girls (1.33, 95% CI 1.01-1.75).

CONCLUSION

The current results showed high constant trends of pre-hypertension and hypertension in Iranian boys and girls, residing in both urban and rural areas.

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.

Obesity and season as determinants of high blood pressure in a school-based screening study

This school-based screening study assessed the prevalence of high blood pressure (BP) levels according to the European Society of Hypertension (ESH) 2016 guidelines. Moreover, risk factors for BP elevation, and the effect of geographic and seasonal factors on BP screening were investigated. BP and anthropometric measurements were obtained from 2832 children and adolescents, aged 6-18 years, during the period 2013-2016. Three BP measurements were performed using a mercury sphygmomanometer, and the mean of the last two was used for the analysis. Obesity was defined according to the International Obesity Task Force (IOTF) criteria. The prevalence of high-normal BP/hypertension and overweight/obesity was 3.7%/0.9%, and 22.9%/8.5%, respectively. The majority of the participants presenting high BP (≥90th percentile) were overweight or obese. Increased prevalence of high BP was observed during spring (5.5%) and winter (5%) compared with 2.5% in autumn (P<0.05). SBP z scores were higher in males, during spring and summer, and in urban areas. In conclusion, a low rate of high-normal and hypertensive BP levels was found despite the high prevalence of overweight and obesity. Overweight and obesity were associated with higher BP levels, but there was also a seasonal difference in the prevalence of high BP levels.

Blood pressure effects of adiposity in non-overweight children aged 6-17 years

BACKGROUND

Obesity is a well-established risk factor of elevated blood pressure; however, the relationships between normal weight status and the risk of hypertension and pre-hypertension are not clear.

AIM

The aim of this study is to describe the blood pressure effects of adiposity in non-overweight children.

METHODS AND RESULTS

In total, 588 097 non-overweight children aged 6-17 years were included from the National Surveys on Students' Constitution and Health. A non-linear relationship was found between age- and gender-standardised body mass index (BMI) z-score and pre-hypertension and hypertension, respectively. The odds ratios and 95% confidence intervals [ORs (95% CIs)] of pre-hypertension were 0.61 (0.59-0.63), 0.67 (0.65-0.68), 0.83 (0.83-0.84), 1.00 (reference), 1.13 (1.12-1.14), 1.18 (1.16-1.20) and 1.20 (1.18-1.22) for BMI z-scores of -1.2, -1.0, -0.5, 0 (reference), 0.5, 0.7 and 0.8, respectively. The ORs (95% CIs) of hypertension were 0.56 (0.54-0.58), 0.62 (0.61-0.64), 0.81 (0.80-0.82), 1.00 (reference), 1.17 (1.16-1.18), 1.23 (1.22-1.5) and 1.27 (1.24-1.29) for BMI z-scores of -1.2, -1.0, -0.5, 0 (reference), 0.5, 0.7 and 0.8, respectively. The above-mentioned associations were consistent in sub-group analysis by age, gender and height.

CONCLUSIONS

Non-linear relationships of BMI z-scores with pre-hypertension and hypertension were found in non-overweight children. Interventions to control blood pressure are also important in non-overweight children.

Prevalence of pre-high blood pressure and high blood pressure among non-overweight children and adolescents using international blood pressure references in developed regions in China

BACKGROUND

There is a lack of data on the prevalence of pre-high blood pressure (PreHBP) and high blood pressure (HBP), based on recent international blood pressure references, in non-overweight children and adolescents.

AIM

To describe the prevalence of PreHBP and HBP in non-overweight children and adolescents in developed regions of China.

SUBJECTS AND METHODS

In total, 588 097 non-overweight children and adolescents aged 6-17 years from the National Surveys on Chinese Students' Constitution and Health in 2015 were included.

RESULTS

The prevalence of PreHBP was 13.41% and subjects in urban areas had a higher prevalence of PreHBP (14.14%) than those in rural areas (12.92%). Subjects in regions with a high (13.56%) or moderate (13.61%) socioeconomic status showed a higher prevalence of PreHBP than those in regions with a relatively low socioeconomic status (12.76%). A similar pattern was found for the prevalence of HBP, and the prevalence of HBP was 18.25% for all participants, 20.55% for subjects in urban areas, 16.71% in rural areas, 18.76% in high socioeconomic areas, 18.62% in moderate socioeconomic areas and 16.70% in relatively low socioeconomic areas.

CONCLUSION

A large proportion of non-overweight children and adolescents had elevated blood pressure and there were urban-rural and socioeconomic disparities in the prevalence of elevated blood pressure.