Diastolic fourth and fifth phase blood pressure in 10-15-year-old children. The Children and Adolescent Blood Pressure Program

Measurement of diastolic blood pressure is complicated by the presence of two diastolic Korotkoff phases (fourth phase and fifth phase) in many children and adults. In the present study, diastolic fourth phase and diastolic fifth phase were evaluated in 1986-1987 in 19,274 Minneapolis-St. Paul school children aged 10-15 years. Approximately 50 percent of the children had no difference between fourth phase and fifth phase (i.e., fourth phase - fifth phase = 0) and 15 percent had a difference of only 1-4 mmHg. However, the fourth phase - fifth phase difference was 5-10 mmHg in 20 percent, 11-20 mmHg in 11 percent and greater than 21 mmHg in 3 percent of the children. Statistical analyses showed that the fourth phase - fifth phase difference tended to be greater in boys than girls and in older than younger children, was positively related to height, systolic blood pressure and fourth phase blood pressure, and negatively related to body mass index and fifth phase blood pressure. Using fifth phase instead of fourth phase in 10-12-year-old children and fourth phase instead of fifth phase in 13-15-year-old children to define diastolic blood pressures significantly changed the prevalence for significant diastolic hypertension by 2-3 percent.     

National standards of blood pressure for children and adolescents in Spain: international comparisons. The Spanish Group for the Study of Cardiovascular Risk Factors in Childhood and Youth.

This study determined age-specific patterns of blood pressure (BP) in Spanish children aged 1-18 years for the purpose of developing BP guidelines for this population. Age- and sex-specific BP levels were constructed by pooling data from 15 studies conducted in Spain. Pooled mean BP levels were then compared with those reported by the US Second Task Force on Blood Pressure Control in Children and those recently reported from a separate pooled analysis of the relevant published surveys collected worldwide. In the Spanish data, the average 1-year age increment in Systolic BP (SBP) was uniform for boys and girls until 13 years at 2 mmHg; for boys aged 13-18 the increase was 1.3 mmHg/year; in contrast, girls reached their maximum values at age 13 and the means remained basically unchanged for female adolescents. Fifth-phase diastolic BP (DBP5) values showed a uniform increase for both boys and girls from ages 6 to 18 years at 0.9 mmHg/year. In most age-sex subgroups, mean SBP values were higher (7-8 mmHg on average) in Spain than in the US. However, Spanish values for SBP were in general only slightly higher or approximately equal to those for the international data, from ages 6 to 18 years. The patterns of change in SBP with age differed somewhat in the three data sets. Comparisons for DBP were limited to the age groups for which readings of DBP5 were available. For DBP5, only slight differences between the Spanish and International pools were observed (ages 6-18 compared), but these values were notably higher than those from the US (ages 13-18 compared). These findings suggest that the use of any particular age-based standard to evaluate readings in children in diverse populations cannot be recommended, at least until there is a better understanding of the true differences in BP between populations.     

The child-adolescent blood pressure study: I. Distribution of blood pressure levels in Seventh-Day-Adventist (SDA) and non-SDA children.

Distribution of systolic and diastolic blood pressures (measured with an automated blood pressure recorder) of two large groups of children-3,159 from Seventh-Day Adventist (SDA) schools and 4,681 from non-SDA schools-are reported. They boys and girls were from four different ethnic groups and attended grades one through 10 in 29 Southern California schools. The analysis of the data failed to show significant differences in mean blood pressure levels between the two groups of children at all ages, despite marked differences in life-style between the two groups, and despite the fact that adults from the two population groups have marked differences in mortality from diseases associated with elevated blood pressure. A comparison between boys and girls showed significantly higher trends in mean systolic blood pressure for boys after age 12. Inter-ethnic comparisons of blood pressure revealed that Black children of both sexes had slightly higher mean blood pressure levels at all ages.     

广州市学龄儿童红细胞分布宽度与血压水平的相关性

探讨广州市6~11岁学龄儿童红细胞分布宽度(red blood cell volume distribution width,RDW)与血压水平的相关性,为有效预防控制学龄儿童高血压提供参考.方法 采用整群抽样的方法抽取广州市6~11岁学龄儿童6 188名,对调查对象进行血压测量和静脉全血细胞分析,分别获得收缩压、舒张压、红细胞数量、血红蛋白和RDW等指标,采用Pearson相关分析和逐步线性回归等方法进行统计分析.结果 广州市6~11岁学龄儿童RDW中位数为13.3%,男生(13.4%)高于女生(13.3%) (Z=8.609,P<0.01);收缩压的中位数为100 mmHg,舒张压中位数为64 mmHg;高血压和高血压前期组学龄儿童RDW高于血压正常组的儿童(H=15.400,P<0.05).Pearson相关分析显示,RDW与收缩压和红细胞数均呈正相关(r值分别为0.044,0.465,P值均<0.01),与血红蛋白呈负相关(r=-0.219,P<0.01).多元线性逐步回归显示,收缩压是RDW的影响因素之一(B=0.002,P=0.008).结论 RDW在高血压和高血压前期学龄儿童中增高,且与收缩压存在关联.     

Combining annual blood pressure measurements in childhood to improve prediction of young adult blood pressure

Tracking correlations of blood pressure (BP) have been reported between levels measured in a single year during both childhood and adulthood. Because of the variability of BP, these correlations increase with the number of visits and measurements per visit in each year. It remains unclear, however, whether such correlations would improve further by combining BP data collected over several years. From 1978-1981, BP was measured annually in a cohort of 339 children in East Boston, MA, at four visits one week apart with three measurements per visit. Of this cohort, then aged 18-26 years, 316 were re-examined in 1989-1990 at three visits one week apart with three measures per visit. Tracking correlations were estimated from levels measured in a single year as well as means averaged over several years in childhood, adjusting for age, year of measurement, as well as smoking, alcohol and oral contraceptive use. Multivariate models were fit to estimate tracking correlations from childhood to young adulthood adjusting for within-person variability. Using a single year in childhood, these were 0.49 in boys and 0.59 in girls for systolic BP and 0.39 and 0.48 for diastolic BP (all p<0.001). Using the long-term average in childhood and adjusting for variability across years, these values were 0.55 in boys and 0.66 in girls for systolic BP and 0.47 and 0.57 for diastolic BP (all p<0.001). We observed concomitant increases in the predictive value of childhood BP for young adult BP. These results suggest that averaging BP over at least two years during childhood increases tracking correlations and improves the prediction of adult values from childhood levels.     

The natural history of blood pressure in childhood

To find out whether there is a relationship between the level of blood pressure in childhood and later on in life, and whether future hypertensives can be identified early in life, we selected a random sample of 596 Dutch children. At the first examination they were 5-19 years of age. In 386 of them (65%) at least five consecutive annual blood pressure measurements were made between 1975 and 1982. The stability of a child's position in the blood pressure distribution ('tracking') was studied by linear regression of follow-up blood pressure on initial blood pressure. 'Tracking' coefficients were 0.4 to 0.6 mmHg/mmHg for systolic pressure, and 0.2 to 0.5 mmHg/mmHg for diastolic pressure after four years of follow-up. Twenty-seven per cent of the boys and 44% of the girls who were in the upper 10% of the systolic blood pressure distribution at the first examination were still there after four years. For diastolic pressure these figures were 25% and 22%, respectively. These observations indicate that there is a moderate degree of blood pressure 'tracking' in childhood. They further imply that it is impossible to detect future hypertensives early in life by measurement of blood pressure only.     

Ethnic differences in blood pressure and heart rate of Chicago school children

In 1975-1978, the Chicago Department of Health conducted a screening program that included measurements of blood pressure, heart rate, height, weight, triceps skinfold thickness, and arm circumference, and calculation of body mass index and muscle circumference for non-public school children. Based on data on 4,086 boys and girls aged 5-10 years from the program, this study examined the ethnic differences in blood pressure and heart rate among children of white, black, Latino, and Oriental ethnicity. Mean levels for both systolic and diastolic blood pressure were higher for Oriental and black children than for white and Latino children. These differences were independent of age, height, weight, and skinfold thickness. The black children had a much lower mean heart rate than the other children. A seasonal variation was observed for systolic blood pressure, i.e., with each sex group, the mean systolic blood pressure adjusted for age, skinfold thickness, and height tended to be higher in spring than in fall and winter. (Note-- no child was screened during the summer because of summer break.) With control for season, ethnic differences in systolic blood pressure disappeared, but not the ethnic differences in diastolic blood pressure and heart rate.     

采用血压身高比筛查广州市部分儿童高血压的初步探索

目的了解广州市儿童的高血压水平,探索采用血压身高比筛查广州市儿童高血压的最佳阈值。方法采用整群随机抽样的方法对广州市6~10岁的5 471名儿童进行血压及相关生长发育指标测量,采用受试者工作特征曲线确定血压身高比预测儿童高血压的能力及最佳阈值。结果用于筛查广州市儿童高血压的收缩压身高比的最佳阈值为男生0.80mmHg/cm,女生0.78mmHg/cm;舒张压身高比的最佳阈值为男生0.51mmHg/cm,女生0.49mmHg/cm,阴性预测值高于阳性预测值,且均大于99%,阳性预测值较低,男生为17.2%,女生为15.9%。入组儿童高血压发病率为3.60%,其中男3.54%,女3.67%。结论血压身高比可作为一种简单精确的指标筛查广州市6~10岁儿童高血压。     

Elevated blood pressure among Southeast Asian refugee children in Minnesota

The blood pressures and body sizes of children aged 10-15 years in the Minneapolis and St. Paul, Minnesota, public schools were measured during 1986 and 1987. The sample consisted of 1,680 Southeast Asian refugees--including 219 Cambodians, 1,086 Hmong, 149 Lao, and 226 Vietnamese--and 3,424 blacks and 11,336 whites. Mean systolic blood pressure in Hmong boys was higher than that in black boys and white boys. Mean systolic blood pressures of Hmong, Lao, and Vietnamese girls were lower than those of black girls and white girls. The mean diastolic blood pressures of Hmong boys and of Cambodian and Hmong girls were greater than those of blacks and whites of the same sexes. Southeast Asian children were shorter and weighed less than black children and white children. Body size may confound associations between ethnic groups and blood pressures and may obscure the problem of hypertension among the smaller Southeast Asian children. Southeast Asian boys had greater mean systolic blood pressures than did black and white boys across all weight strata; a similar contrast among girls did not reveal this difference. The risk of hypertension, defined by US National Heart, Lung, and Blood Institute guidelines, was assessed in multiple logistic regression analyses that controlled for differences in weight, height, age, and pulse rate. The odds ratios for hypertension, relative to blacks and whites of the same sexes, were 2.69 (95% confidence interval (CI) 1.85-3.65) in Hmong boys, 2.89 (95% CI 1.35-6.21) in Lao boys, 2.10 (95% CI 1.03-4.28) in Cambodian girls, and 1.49 (95% CI 1.00-2.20) in Hmong girls. Hypertension and subsequent cardiovascular disease may emerge as a significant problem among Southeast Asian refugees in the United States.     

Trajectory of systolic blood pressure in children and adolescents

PURPOSE: Rapid height and weight changes during childhood contribute markedly to blood-pressure change during children's physical growth. This article evaluates the differences in systolic blood pressure (SBP) growth or changes between four gender-ethnic groups: African American males (AM), Caucasian males (CM), African American females (AF), and Caucasian females (CF). METHODS: Subjects 6-9 years old at entry (n = 1302) were followed for 12 years. The repeated-measure data of SBP were analyzed using the Gompertz growth model with random coefficients. RESULTS: Mean SBP (mmHg) at age 6 years was lowest in African American girls (82.23 +/- 0.76) and highest in Caucasian boys (102.83 +/- 0.5). And for both ethnic groups, girls had lower levels at which SBP growth stopped. The peak growth ages (years) also differed by group: 9.30 +/- 0.73, 9.91 +/- 0.28, 10.00 +/- 0.82, and 10.60 +/- 0.22 for African American girls, African American boys, Caucasian girls and Caucasian boys, respectively. CONCLUSION: SBP growth differed among gender-ethnic groups with respect to mean SBP level at age 6, the level at which SBP growth stops and the mean age at which SBP growth rate was at its peak.     

Determinants of blood pressure in 7th grade Jerusalem school children

The determinants of blood pressure level were analyzed in a group of 1154 Jerusalem school children aged 12.After controlling for age, significant differences in blood pressure measurements were found between three groups: boys, pre-menarche girls and post-menarche girls. A comparison of the means of selected biological variables showed that girls who have reached menarche have levels of systolic blood pressure, weight, height and Quetelet's index higher than boys and pre-menarche girls. However, levels of triceps skinfold thickness and pulse rate were similar in the two groups of girls and higher than in boys. Using multiple regression analysis, we found that much of the variance (boys 29%, post-menarche girls 21% and pre-menarche girls 15%) of systolic blood pressure, could be explained by a combination of biological variables (Quetelet, pulse rte, triceps skinfold thickness and height) while these variables explained a much 'smaller proportion (boys 12%, postmenarche girls 17% and pre-menarch 9%) of diastolic blood pressure variance. The predictive power of systolic blood pressure by the measured biological variables was higher in boys than in girls, However, diastolic blood pressure was better predicted by the biological variables in the group of girls with menarche than in other groups.Elevated blood pressure was observed in 3.2% of the examined children. High values for Quetelet's index were observed in 6.4%. The prevalence of elevated measurements of blood pressure and Quetelet's index were significantly higher in girls with menarche. Among children aged 12, the association between socio-demographic characteristics and blood pressure level was weak, as measured in multiple regression analysis.     

A relation between blood pressure and stiffness of joints and skin

BACKGROUND: Blood pressure, particularly pulse pressure, is associated with arterial wall stiffness, but little is known about its relation to stiffness of other parts of the body. We examined the extent to which blood pressure levels in young healthy children are related to stiffness of various tissues. METHODS: In November 2000, we studied 95 healthy prepubertal children (41 boys and 54 girls, within age range 8-10 years) from two primary schools in the city of Zeist, The Netherlands. Systolic and diastolic blood pressure and pulse pressure were analyzed in relation to various tissue indicators of stiffness, including active joint mobility and skin extensibility. All results were adjusted for age, sex, body height, body weight and muscle strength as possible confounders. RESULTS: Diastolic blood pressure was lower with increased active joint mobility (multivariate generalized linear regression coefficient = -4.5 mmHg per standard deviation [SD] joint mobility; 95% confidence interval [CI] = -7.8 to -1.2). Pulse pressure was lower with increased skin extensibility (-3.2 mmHg per SD skin extensibility; CI = -5.2 to -1.1), through a higher diastolic blood pressure (2.0 mmHg per SD skin extensibility; CI = 0.2-3.9) and possibly lower systolic blood pressure (-0.8 mmHg per SD skin extensibility; CI = -3.5 to 1.9). These associations were mutually independent. Additional adjustment for reported musculoskeletal problems or physical activity levels did not materially change the findings. CONCLUSIONS: Our findings support the hypothesis that constitutional stiffness of body tissues may be associated with blood pressure levels and eventually cardiovascular risk.     

兰州市中小学生睡眠时间和血压的关系

探讨兰州市7~18岁中小学生睡眠时间和血压的关系,为预防青少年高血压提供参考.方法 采用分层随机整群抽样的方法,选取兰州市4 200名中小学生进行身高、体重和血压测量,并调查睡眠时间.采用t检验和多元线性回归分析睡眠时间和血压之间的关系.结果 男生收缩压和舒张压均高于女生,差异有统计学意义(t值分别为11.115,4.402,P值均<0.01);在7~12,13~15,16~18岁3个年龄组中,无论男女,睡眠时间充足学生的收缩压和舒张压均低于睡眠时间不足的学生,差异均有统计学意义(P值均<0.01).在调整了身高、体重、体质量指数等因素的多元线性回归模型中,中小学生的睡眠时间与收缩压、舒张压的关联均有统计学意义(JP值均<0.05).结论 兰州市中小学生睡眠时间和血压之间存在关联性,保证学生睡眠时间可能有助于儿童青少年高血压的预防.     

Physical Activity and Blood Pressure Patterns: A Cross-Sectional Study on Portuguese School Children Aged 8 Through 13 Years Old

The relation between blood pressure and physical activity was examined. A sample of 474 children (242 boys and 232 girls), aged 8 through 13 years were involved in this study. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were evaluated. An adapted version of the Weekly Activity Checklist was applied to the sample for diagnosis of their physical activity. SBP and DBP increased from 8 to 13 years in both sexes (boys: SBP, 114.8 10.9 to 120.5 9.4 mmHg and DBP, 59.1 8.3 to 62.3 6.8 mmHg; girls: SBP, 115.2 12.1 to 120.2 10.9 mmHg, and DBP, 58.9 9.3 to 60.5 9.6 mmHg). Correlations, after adjustment for age, of physical activity index with SBP (r = -.20, p < .05) and DBP (r = -.17, p < .05) were significant in boys, whereas in girls no significant association was found. This article provides some preliminary data on the blood pressure and physical activity patterns of school children in the Porto (Portugal) region.     

The association of fat patterning with blood pressure in rural South African children: the Ellisras Longitudinal Growth and Health Study

BACKGROUND: Hypertension is one of the major causes of death in developed and underdeveloped nations. Essential hypertension and obesity may have their inception in childhood, with little data in African children to support these findings. Objectives were to determine the prevalence of overweight and hypertension in rural children in South Africa. Additionally, the association between fat-patterning ratios and blood pressure (BP) was investigated. METHODS: Data were collected from 1884 subjects (967 boys and 917 girls), aged 6-13 years, participating in the Ellisras Longitudinal Study. Height; weight; and triceps, biceps, subscapular, and suprailiac skinfolds were measured according to the protocol of the International Society for the Advancement of Kinanthropometry. Skinfold ratio was used as an indicator of the central pattern of body fat. Internationally recommended cut-off points for body mass index (BMI) were used. Hypertension, defined as the average of three separate BP readings where the systolic BP or diastolic BP is >or=95th percentile for age and sex, was determined. RESULTS: The prevalence of hypertension ranged from 1 to 5.8% for boys and 3.1 to 11.4% for girls, and that of overweight from 1.1 to 2.9% for boys and 0.6 to 4.6% for girls. The association between high systolic BP and high BMI was -3.0, while that for high diastolic BP and high BMI was -0.68. CONCLUSIONS: The prevalence of hypertension is evident from the age 6 years for girls, while that of overweight was low. Overweight became evident from the age 10 to 13 years for both sexes. A significant association between high diastolic BP and high BMI was noted, while children with low BMIs were less likely to be hypertensive. Investigating habitual physical activity, fitness and dietary patterns will shed more light on the association of fat patterning and BP in this population.     

Blood pressure, physical activity and anthropometry in adolescents]

The relationship of blood pressure with physical activity and anthropometry was studied in 295 adolescents (mean age, 15.3 years) who entered 1. "formación profesional" (a technological training) in 1990 in Puerto Real, a village of Cádiz, Spain. Systolic and diastolic (fifth-phase Korotkoff) blood pressure, and anthropometrics measurements (weight, height and triceps and subscapular skinfolds thickness) were measured with standardized techniques. Habitual and sports physical activity were assessed by a self-reported questionnaire. The results reported in this study suggest that systolic blood pressure is associated with habitual physical activity in girls, and that the systolic blood pressure is associated weakly with sports activity in girls and in boys. The stronger predictor of blood pressure was Quetelet Index (kg/m2).     

The relationship between elevated blood pressure and obesity in Black children.

Blood pressures, heights and weights were measured in 1,692 elementary school black children. Elevated blood pressure (EBP) was defined as a systolic or diastolic reading above the 90th percentile for age, and weights were categorized into five classes based on weight for height norms. Systolic EBP children, whether boys or girls, were three times as likely to be obese as black children in the total population, and a similar relationship held for diastolic EBP children.     

Blood pressure in schoolchildren in northwest India.

Blood pressure was determined among 2,453 schoolchildren aged between 7 and 16 years in the northwest Indian town of Chandigarh to establish the norms. The percentiles were calculated for each age group in both sexes. Both systolic and diastolic blood pressure had a positive correlation with age, weight, height, and body surface area (r = 0.112-0.178, p less than 0.01). There was no difference in the systolic and diastolic pressures of boys compared with girls of corresponding age. The upper limits of normal (90th percentile) systolic/diastolic pressure were 113/74, 119/76, and 126/79 in children aged 7-9 years, children aged 10-12 years, and adolescents aged 13-16 years, respectively. The lower limits of hypertension (95th percentile) for systolic/diastolic pressure were 119/80, 124/81, and 132/82 in each of these groups, respectively. The 99th percentile values indicative of severe hypertension for systolic/diastolic pressure in these groups were 128/88, 135/88, and 149/89, respectively. The 90th percentile of height and weight shown in the percentile table should be taken into consideration whenever blood pressure exceeds the 90th percentile for age and sex while planning the management of an individual.     

Blood pressure and mortality risk in the elderly

Blood pressure was assessed between 1981 and 1983 in all persons over age 65 years in three communities (East Boston, Massachusetts; New Haven, Connecticut; and Iowa and Washington countries, Iowa), and cause-specific mortality was monitored annually over the subsequent 5 years as part of the National Institute on Aging-sponsored Established Populations for Epidemiologic Studies of the Elderly. Each community had 80% or more participation: in East Boston, 3,809 persons with 903 deaths, in New Haven, 2,812 persons with 804 deaths, and in Iowa, 3,673 persons with 763 deaths. At 2 years, odds of death from all causes were higher in the low (less than 130 mmHg) than the middle (130-159 mmHg) systolic blood pressure group for persons aged 65-79 years in all three populations. By 5 years, cardiovascular death increased with increasing systolic pressure in all three communities and reached significance in Iowa. Cancer death was highest in the low systolic pressure stratum in all three centers. All-cause, cardiovascular death, and cancer mortality was highest in the low (less than 75 mmHg) diastolic blood pressure group in East Boston, even at 5 years. Blood pressures obtained 9 years earlier in 2,079 (68%) of the East Boston participants showed a significantly higher risk of cardiovascular death with increasing systolic pressure and no relation between diastolic pressure and mortality risk. In the elderly, excess mortality at lower levels of blood pressure during early follow-up may in part be due to the effects of illness and disability present at baseline. This may obscure the usual rise in mortality with increasing systolic pressure. There is no consistent relation between diastolic pressure and mortality.     

宁夏地区2005和2014年7~17岁回族儿童血压比较

了解宁夏7~17岁回族儿童2005和2014年高血压及血压值变化情况,为宁夏回族儿童心脑血管疾病的早期预防提供基础资料.方法 利用2005和2014年宁夏中小学生体质与健康调研数据,提取回族儿童血压资料,对高血压及血压值进行分析.结果 2014年宁夏7~ 17岁回族儿童高血压检出率为15.2%,比2005年增加了11.4百分点,差异有统计学意义(x2=380.53,P<0.05),增速最大的年龄段为17岁组,增加了16.2百分点.舒张压从2005年的(65.8±8.3) mmHg增长至2014年的(69.0±9.8) mmHg,收缩压从(98.6+ 11.6) mmHg增至(107.4±11.9) mmHg,差异均有统计学意义(t值分别为-36.33,-18.02,P值均<0.01),并且血压值随年龄的增加而增加.男生高血压检出率从2005年的3.4%增加至2014年的14.2%,女生从4.2%增加至16.2%,9年间分别增加了10.8和12.0百分点,虽然2个年份高血压检出率均为女生高于男生,但差异均无统计学意义(P值均>0.05).城市儿童高血压检出率从2005年的5.1%增至2014年的15.7%;乡村儿童从3.3%增加到14.9%,分别增加了10.6和11.6百分点,乡村儿童的高血压检出率增速虽高于城市儿童,但差异无统计学意义(x2=1.19,P=0.271).肥胖儿童高血压检出率2005为15.3%,2014为42.1%,均明显高于体重正常组(x2=29.48,392.38,P值均<0.01).结论 宁夏7~ 17岁回族儿童高血压检出率从2005年至2014年出现明显的增加趋势,可通过控制儿童肥胖超重遏制儿童高血压的增长.