Longitudinal data of blood pressure and pulse frequency during childhood (author's transl)

From 1968-1980 the development of blood pressure and pulse frequency in 221 healthy boys and 230 healthy girls aged 2-16 years was studied longitudinally. An automatic blood pressure device recording on a paper tape pulse frequence as well was used. Systolic readings are taken at the first appearance, diastolic readings at the disappearance of the Korotkoff sounds. A steady increase of the systolic, and to a lesser extent, of the diastolic pressure can be observed. Boys have a more pronouned increase of systolic pressure than girls. From year 2-16 the 50th percentile increases from 90 mm Hg to 128 mm Hg in boys and from 92 mmHg to 116 mm Hg in girls. The 50th percentile of diastolic pressure increases from 61 to 66 mm Hg in boys and 65 to 71 mm Hg in girls. Pulse frequency of boys is comparable to that of girls. The 50th percentile decreases from 100 to 75 beats. Increasing age is paralleled by decreasing pulse frequency.     

The association of caffeinated beverages with blood pressure in adolescents

OBJECTIVE: To assess the association between the consumption of caffeinated beverages and blood pressure in African American and white adolescents. DESIGN: This study was part of ongoing research examining stress-induced hemodynamic responses in adolescents. African American and white adolescents (n = 159) selected foods and beverages for a 3-day sodium-controlled diet. Caffeine in these foods was used to stratify participants into 3 categories (0-50 mg/d, >50-100 mg/d, and >100 mg/d). Before menu selection, blood pressure readings were obtained. STATISTICAL ANALYSIS: A general linear model (multiple regression with both categorical and continuous variables) was developed to assess the effects of race, category of caffeine intake, and interaction of race and caffeine intake on systolic and diastolic blood pressure controlling for sex and body mass index (calculated as weight in kilograms divided by height in meters squared). RESULTS: The association between systolic blood pressure and caffeine category varied by race (P =.001). African Americans consuming more than 100 mg/d of caffeine had higher systolic blood pressure readings than the groups consuming 0 to 50 mg/d (mean difference, 6.0 mm Hg; 95% confidence interval [CI], 2.3 to 9.7) or more than 50 to 100 mg/d (mean difference, 7.1 mm Hg; 95% CI, 3.4 to 10.7). The effect on diastolic blood pressure was less pronounced (P =.08). The diastolic blood pressure of the group consuming more than 100 mg/d was 3.7 mm Hg (95% CI, 0.41 to 7.0) higher than the group consuming more than 50 to 100 mg/d and was not statistically different from the group consuming 0 to 50 mg/d (mean difference, 2.4 mm Hg; 95% CI, -0.9 to 5.8). There was no evidence that the association between diastolic blood pressure and caffeine intake varied by race (P =.80). CONCLUSIONS: For adolescents, especially African American adolescents, caffeine intake may increase blood pressure and thereby increase the risk of hypertension. Alternatively, caffeinated drink consumption may be a marker for dietary and lifestyle practices that together influence blood pressure. Additional research is needed owing to rising rates of adolescent hypertension and soft drink consumption.     

Comparison of auscultatory and oscillometric blood pressures

OBJECTIVE: To study the differences in blood pressure readings between the auscultatory and oscillometric (Dinamap model 8100; Critikon, Tampa, Fla) methods. DESIGN: Survey of 2 blood pressure instruments. SETTING: Public schools. PARTICIPANTS: Seven thousand two hundred eight schoolchildren aged 5 through 17 years. MAIN OUTCOME MEASURE: Blood pressure levels. RESULTS: For all children combined, Dinamap systolic pressure readings were 10 mm Hg higher (95% confidence interval, -4 to 24 mm Hg) than the auscultatory systolic pressure readings. Dinamap diastolic pressure readings were 5 mm Hg higher (95% confidence interval, -14 to 23 mm Hg) than the auscultatory Korotkoff phase V diastolic pressure readings. CONCLUSION: These findings preclude the interchange of readings by the 2 methods. Caution must be exercised in the diagnosis of hypertension when an automated device is used.     

Ambulatory blood pressure monitoring

Ambulatory blood pressure monitoring (ABPM) in adults is proving to be useful. The aim of this study was to determine if ABPM is accurate in the lower blood pressure range encountered in children and, equally important, whether it is acceptable to children. Thirty one children, between the ages of 6 and 18 years, were assessed using an ambulatory blood pressure monitor that uses an auscultatory method. Blood pressure was measured in the contralateral arm with a mercury sphygmomanometer and an oscillometric device at the beginning and end of the study for comparison. Over a blood pressure range of 90-130 mm Hg systolic and 40-80 mm Hg diastolic, a close agreement was found with the sphygmomanometer; the limits of agreement (+/- 2 SD) were 11.6 mm Hg for systolic blood pressure and 13.6 mm Hg for diastolic blood pressure. The bias was less than 1.0 mm Hg. The ambulatory device was worn by all patients for at least 16 hours with an average of 52 recordings per patient. The majority found the device comfortable to wear and were not woken from sleep.     

Ambulatory blood pressure monitoring.

Ambulatory blood pressure monitoring (ABPM) in adults is proving to be useful. The aim of this study was to determine if ABPM is accurate in the lower blood pressure range encountered in children and, equally important, whether it is acceptable to children. Thirty one children, between the ages of 6 and 18 years, were assessed using an ambulatory blood pressure monitor that uses an auscultatory method. Blood pressure was measured in the contralateral arm with a mercury sphygmomanometer and an oscillometric device at the beginning and end of the study for comparison. Over a blood pressure range of 90-130 mm Hg systolic and 40-80 mm Hg diastolic, a close agreement was found with the sphygmomanometer; the limits of agreement (+/- 2 SD) were 11.6 mm Hg for systolic blood pressure and 13.6 mm Hg for diastolic blood pressure. The bias was less than 1.0 mm Hg. The ambulatory device was worn by all patients for at least 16 hours with an average of 52 recordings per patient. The majority found the device comfortable to wear and were not woken from sleep.     

Renal function 9 to 17 years after childhood lead poisoning

Renal function was studied in 74 subjects who, between 1966 and 1972 (ages 1 to 6 years) had had blood lead levels (PbB) greater than or equal to 100 micrograms/dl (range 100 to 471 micrograms/dl, median 142 micrograms/dl) and in 21 sibling controls. PbB measured in 1983 in study subjects remained significantly higher than in sibling controls (mean +/- 1 SD 14.5 +/- 4.5 vs 11.6 +/- 2.6 micrograms/dl, P less than 0.01). The two groups did not differ in development of hematuria or leukocyturia. The frequency of elevated serum creatinine concentration, depressed creatinine clearance, elevated protein excretion, low urinary osmolality, elevated serum beta 2-microglobulin (beta 2-M), and elevated fractional excretion beta 2-M % X 100 was similar in the two groups. Mean values for these tests were similar in study subjects compared with sibling controls. Mean systolic blood pressure was significantly higher in study subjects compared with that in sibling controls (117 +/- 12 vs 109 +/- 10 mm Hg), but the control group contained a preponderance of females and the study group had more overweight females; mean diastolic blood pressure was similar in the two groups. We conclude that in our adolescent subjects who had had lead poisoning 9 to 17 years earlier, there is little if any evidence of chronic nephropathy.     

北京地区儿童及青少年血压分布特征

目的了解北京地区儿童青少年血压的现况。方法按分层整群随机抽样法在北京市4个城区和3个郊区县的3—18岁儿童和青少年中,用“美国高血压教育项目工作组”和“中国高血压防治指南”推荐的测量方法进行收缩压（SBP）和舒张压（DBP）测量。记录、整理、分析血压测量的结果。结果北京地区3—18岁儿童青少年血压调查的有效数据人数20780人,城区10582人（50．9％）,郊县10198人（49．1％）;男10398人（50．0％）,女10382人（50．0％）。男童血压高于女童[SBP：（106±12）mmHgVS（101±11）mmHg,u=27．14,P〈0．01;DBP：（67±9）mmHgvs（65±8）mmHg,u=14．14,P〈0．01]（1mmHg=0．133kPa）。男女童血压均随年龄增长有逐渐增高的趋势,且SBP上升幅度较DBP高。城区儿童SBP和DBP的平均水平低于郊县儿童[SBP：（103±12）mmHgVS（104±12）mmHg,u=2．55,P〈O．05;DBP：（66±8）mmHgVS（67±9）mmHg,u=6．73,P〈0．01]。血压与年龄、身高、体重及体块指数（BMI）均有显著的正相关（P〈0．001）,收缩压与各变量的相关程度均较舒张压高。依据1987年北京市6—18岁儿童青少年性别年龄别血压标准,本次调查6～18岁儿童青少年高血压检出率为8．1％。结论获得了北京地区儿童青少年血压的分布特征;血压值与儿童的性别、年龄、身高、体重和BMI相关。     

Dietary nutrients and blood pressure in urban minority adolescents at risk for hypertension

OBJECTIVE: To determine if blood pressure (BP) level is associated with dietary micronutrients in adolescents at risk for hypertension. DESIGN: Adolescents aged 14 to 16 years, with BP higher than the 90th percentile on 2 separate measurements in a school setting, had diet assessments. A 24-hour intake recall was obtained on 180 students (108 boys and 72 girls). Folic acid intake was used as an index of fruit, vegetable, and whole grain intake; the high folate group had a folate intake greater than the recommended daily allowance and the low folate group had a folate intake less than the recommended daily allowance. Data were analyzed by 2-way analysis of variance. RESULTS: Mean diastolic BP was significantly higher in the low folate vs the high folate group (boys: 72 vs. 67 mm Hg; girls: 76 vs. 73 mm Hg; P =.008). The difference in systolic blood pressure was not significant. There was no difference in body mass index between the diet groups. Sodium intake per 4184 kJ was not different. The low folate group had significantly lower intakes per 4184 kJ of potassium (P =.002), calcium (P = .001), magnesium (P<.001), and total intake of beta carotene, cholecalciferol, vitamin E, and all B vitamins. CONCLUSIONS: Among adolescents at risk for hypertension, BP was lower in those with higher intakes of a combination of nutrients, including potassium, calcium, magnesium, and vitamins. Dietary benefits on BP observed on diets rich in a combination of nutrients derived from fruits, vegetables, and low-fat dairy products could contribute to primary prevention of hypertension when instituted at an early age.     

Assessment of left ventricular function in secundum atrial septal defect: evaluation by determination of volume, pressure, and external systolic time indices.

Left ventricular function and volume data from 17 control subjects and 27 young patients with secundum atrial septal defect (ASD) without overt left or right ventricular failure were compared. ASD patients were subdivided in low shunt (Qp/Qs less than 2.0) and high shunt (Qp/Qs larger than or equal to 2.0) groups. Mean left ventricular (LV) stroke volume was significantly less in ASD patients (46 +/- 16 ml/m2 in the low shunt and 44 +/- 9 ml/m2 in high shunt group) compared with control patients (51 +/- 13 ml/m2, P less than 0.01 and P less than 0.02, respectively). There was no significant difference in mean left ventricular end-diastolic volume (LVEDV) between any group of patients (control subjects 67 +/- 17 ml/m2; low shunt ASD 66 +/- 17 Ml/m2, and high shunt ASD 62 +/- 12 ml/m2). High shunt ASD had a significantly lower cardiac index compared with control patients (5.0 liters/min/m2 vs. 5.9 liters/min/m2, P less than 0.02). Both low shunt and high shunt ASD showed significantly lower stroke work indices than control subjects (42 +/- 13 GmM/m2 and 37 +/- 8 GmM/m2 compared with 51 +/- 14 GmM/M2 , P less than 0.05 and P less than 0.001, respectively) but only the high shunt group had a significantly lower peak systolic pressure (94 +/- 12 mm Hg vs. 109 +/- 11 mm Hg for control patients, P less than 0.01). There was no significant difference between the control and ASD groups in LV end-diastolic, mean right atrial, right ventricular end-diastolic, and pulmonary pressures. External systolic time intervals were compared in 5 control and 12 ASD patients. There was no significant difference between the two groups of patients in absolute values or indices for pre-ejection period, ejection time, or electromechanical systole. However, the ratio of the pre-ejection period index to left ventricular ejection time index (PEPI/LVETI) was significantly higher in ASD patients (P less than 0.05). In young subjects with large shunt ASD, certain indicators of left ventricular function are depressed. Evaluation of PEPI/LVETI may allow noninvasive determination of LV function.     

Response of hypertensive adolescents to dynamic and isometric exercise stress.

Isometric handgrip and dynamic exercise stress tests were performed on 109 hypertensive and 74 normotensive subjects 14 to 17 years old. The hypertensive subjects had resting systolic or diastolic pressures persistently above the 95th percentile on four consecutive examinations. Blood pressures and ECGs were recorded during isometric handgrip (25% maximum effort for four minutes) and bicycle ergometry until the subject was exhausted. The hypertensive subjects increased systolic pressure by an average 16 mm Hg with isometric exercise and 53 mm Hg with dynamic exercise. Control subjects had similar pressure changes, averaging 18 and 54 mm Hg, respectively. During isometric handgrip stress, diastolic pressures increased 12 mm Hg in hypertensive subjects and 18 mm Hg in control subjects. Only two hypertensive adolescents developed systolic pressures exceeding 200 mm Hg during dynamic exercise stress, and none developed systolic pressures above 200 mm Hg during isometric exercise stress. None of the normotensive or hypertensive subjects developed cardiac arrhythmias and the prevalence of ST segment depression during maximal stress was less than 2% in both groups. Therefore, in adolescents with mild to moderate hypertension the risk of developing significant ECG or hemodynamic abnormalities during mild isometric or heavy dynamic exercise is small. We believe the decision to restrict physical activity of an adolescent with elevated pressures should be based on the development of abnormal ST segment depression, cardiac arrhythmias, or excessive blood pressures at the time of exercise stress testing.     

Treatment of high-renin hypertension with propranolol in children after renal transplantation.

Ten children with hypertension poorly controlled with other drugs and high peripheral plasma renin activity after renal transplantation were treated with propranolol. The mean systolic pressure decreased from 139 to 127 mm Hg (p less than 0.05) and the mean diastolic pressure from 98 to 83 mm Hg (p less than 0.01). Eight children had an antihypertensive response; two did not respond. The maximum dose of propranolol in responders varied from 1.0 to 6.2 mg/kg/day and duration of treatment until response varied from four to 49 days. PRA, repeated in seven responders, decreased in all (p less than 0.01).There was no correlation between changes in PRA and blood pressure. Propranolol was well tolerated and was a valuable antihypertensive drug in these children.     

Absent circadian variation of blood pressure in patients with anorexia nervosa

OBJECTIVE: To examine whether circadian rhythm of blood pressure (BP) is altered in patients with anorexia nervosa (AN), and if so, to determine whether it is reversible after refeeding.Study design: Ambulatory BP monitoring was performed on 17 female inpatients with AN (mean age, 13.3 +/- 1.9 years) at the time of admission and serially during refeeding; 17 age-matched normal weight, normotensive female inpatients served as control subjects. RESULTS: Patients with AN had lost an average of 23.4% +/- 11.5% of body weight before the illness. Weight after refeeding was 105.6% +/- 9. 2% of that before illness. Mean 24-hour systolic BP (SBP) (96.5 +/- 8.6 mm Hg) and diastolic BP (DBP) (53.4 +/- 5.8 mm Hg) were significantly lower in patients with AN compared with those of control subjects (SBP, 106.1 +/- 6.5 mm Hg; DBP, 60.2 +/- 5.8 mm Hg). Although awake SBP and DBP were also lower in patients with AN, asleep SBP and DBP were not statistically different from those of control subjects. Night/day BP ratio in the control group was 0.93 +/- 0.06 in systolic and 0.92 +/- 0.09 in diastolic. Those values were significantly elevated in patients with AN (systolic 1.00 +/- 0. 09 and diastolic 1.00 +/- 0.09). After refeeding, the ratio decreased to 0.88 +/- 0.09 and 0.90 +/- 0.08,respectively (both P <. 05 vs baseline). CONCLUSIONS: In patients with AN, circadian variation of BP is absent. This reverts to normal after refeeding.     

Random-zero sphygmomanometer, Rose's tape, and the accuracy of the blood pressure measurements in children.

In the Cardiovascular Risk in Young Finns project, blood pressure (BP) was measured in 3549 randomly selected children aged 6-18 y in 1980, and 2887 and 2500 of the same individuals in 1983 and 1986, respectively. An ordinary mercury sphygmomanometer (OMS) was used in the first two surveys and a random-zero sphygmomanometer (RZS) in the third survey. Systolic and diastolic BP were lower when measured with an RZS than with an OMS and the shape of the age-related BP curve obtained with an RZS was significantly different from that obtained with an OMS, because low BP values were apparently measured more accurately with the former. Use of the RZS did not affect the distribution of the BP values. Rose's tape readings were used to evaluate the effect of training and to control the accuracy of the BP measurements. According to Rose's tape readings, Korotkoff's 4th phase BP was more difficult to measure accurately than 5th phase (p = 0.002). The mean values for the differences between the correct and actual BP readings on the Rose's tape were -1.2 mm Hg (SD 2.1) for systolic BP, 8.3 mm Hg (SD 13.6) for diastolic Korotkoff's 4th phase BP, and 1.2 mm Hg (SD 7.0) for diastolic Korotkoff's 5th phase BP, with a negative value indicating that the BP phase was measured lower than the correct value. Terminal digit preference was present in each survey to such an extent that it could have hampered the reaching of reliable conclusions from the data obtained with an OMS. The bias caused by terminal digit preference was obviated by the RZS.(ABSTRACT TRUNCATED AT 250 WORDS)     

Cerebral blood flow velocity in term newborn infants: changes associated with ductal flow

The effects of ductal closure on range-gated pulsed Doppler cerebral blood flow velocity (CBFV) patterns in the internal carotid, anterior cerebral, and middle cerebral arteries were studied in 10 normal term infants (mean birth weight 3302 +/- 294 g (SD) and mean gestational age 39.6 +/- 1.3 weeks). Pulsatility was calculated from flow velocities and used as an estimate of cerebral blood flow (CBF). Ductal closure was associated with a rise in mean blood pressure from 45.0 +/- 4.2 to 51.3 +/- 6.5 mm Hg (P less than 0.05) and a significant decrease in pulsatility in all three vessels (mean = 0.77 +/- 0.07 vs 0.70 +/- 0.05 (P less than 0.02]. Changes in pulsatility were correlated with changes in mean blood pressure (P less than 0.02), providing evidence that systemic blood pressure may influence postnatal cerebral arterial pulsatility indices. We also noted significant differences in the velocity and pulsatility of individual vessels that were independent of blood pressure, suggesting that Doppler flow studies may be useful in describing regional CBF patterns. The temporal association between ductal closure and decreased pulsatility suggests that CBFV patterns reflect ductal shunting in normal term newborn infants. Diastolic runoff and reduced systemic blood pressure in the presence of ductal shunting appear to reduce diastolic flow velocity and increase CBFV pulsatility in normal term infants during the first days of life. Normal mechanisms of cerebral autoregulation compensate for decreased flow with vasodilation; therefore the increased pulsatility associated with ductal shunting may be due to diastolic runoff rather than increased cerebrovascular resistance.     

Transcutaneous monitoring of oxygenation: what is normal?

We examined 55 infants on 119 occasions, from birth to 6 months, to obtain normal data and to establish guidelines for the management of oxygen-dependent infants with chronic lung disease. Transcutaneous oxygen tension (tcPo2) and saturation (tcSao2) were monitored during four states: awake, feeding, quiet sleep, and active sleep. Lowest values (mean +/- SD) for tcSao2 were recorded in all states during the first week of life: awake 96.2% +/- 2.6%, feeding 91.2% +/- 3.7%, quiet sleep 93.2% +/- 2.9%, and active sleep 92.1% +/- 2.9%. After the first week the results were affected by state rather than age, with differences observed between awake and feeding (P less than 0.0001), awake and asleep (P less than 0.00001), and quiet sleep and active sleep (P less than 0.001). The findings for tcPo2 were less consistent and probably affected by the characteristics of skin. In the first week, values were as follows: awake 83.5 +/- 10.1 mm Hg, feeding 73.4 +/- 10.1 mm Hg, quiet sleep 78.5 +/- 10.9 mm Hg, and active sleep 73.4 +/- 11.4 mm Hg. Subsequently, only the state effect remained, and significant differences existed between awake and feeding (P less than 0.0001) and awake and asleep (P less than 0.00001). We conclude that transcutaneous blood gas measurements are affected by state of the infant.     

Correlations between the intrauterine metabolic environment and blood pressure in adolescent offspring of diabetic mothers

OBJECTIVE: To investigate associations between maternal diabetes and blood pressure (BP), obesity, impaired glucose tolerance, and serum lipids in offspring and whether these parameters correlate with metabolism during pregnancy. STUDY DESIGN: Body mass index, BP, serum glucose, and insulin during an oral glucose tolerance test, and lipid concentrations were measured in 99 offspring of diabetic mothers (ODM) and 80 members of a control group. RESULTS: ODM were more obese (body mass index 22.5 +/- 5.6 vs 20.3 +/- 4.0 kg/m(2)) and had higher systolic (8 mm Hg) and mean arterial BP (4 mm Hg) but similar diastolic BP compared with the control group. ODM had higher 2-hour glucose (6.6 +/- 1.3 vs 5.7 +/- 0.9 mmol/L) and insulin (580 +/- 544 vs 377 +/- 239 pmol/L) concentrations but lower fasting concentrations of low-density lipoprotein (2.54 +/- 0.67 vs 2.82 +/- 0.70 mmol/L) and total cholesterol (4.01 +/- 0.80 vs 4.40 +/- 0.78 mmol/L). In both groups body mass index, triglycerides, and fasting and 2-hour glucose concentrations showed correlations with BP measurements. Fasting insulin was correlated with BP readings only in the ODM. Correlations were found between second- and third-trimester maternal free fatty acid concentrations and diastolic and mean arterial BP. Third-trimester beta-hydroxybutyrate was correlated with mean arterial BP. CONCLUSIONS: In ODM, abnormalities in weight and glucose tolerance are associated with abnormal maternal metabolism. Higher BP is an additional abnormality associated with fetal overnutrition.     

The effect of increased pulmonary blood flow on the pulmonary vascular bed in pigs.

Increased pulmonary blood flow was produced in 1-month-old piglets by means of left pneumonectomy, arteriovenous fistulas in the neck, and a combination of both. Physiologic and histologic studies of the pulmonary vascular bed were done 1-9 months after operation. A progressive, moderate increase in pulmonary artery (PA) pressure was observed, especially between 1 and 6 months after surgery. This was flow related, i.e., the group with the highest flow (pneumonectomy plus fistula) was found to have the most prominent increase in pressure. Mean Pa pressure at 6 months was 28.7 +/- 0.07 mm Hg in this group, vs 24.4 +/- 0.48 mm Hg in the group with pneumonectomy alone and 17.2 +/- 0.48 mm Hg in controls (P less than 0.01). The pressure response to hypoxia in pigs with high pulmonary blood flow was not different from that found in control animals. Histologic studies revealed that small arteries and arterioles of pigs with high pulmonary blood flow had a decreased relative wall thickness because of dilation up to 6 months follow-up. This was flow related, the group with the highest flow having the lowest wall thickness to vessel diameter ratio; relative wall thickness (in percentage of the vessel diameter ) at 6 months was 6.1 +/- 0.44% in pigs with with pneumonectomy plus fistula, vs 9.6 +/- 0.40% in the group with pneumonectomy alone and 11.2 +/- 0.61% in controls (P less than 0.01). In the group with the highest flow, thick walled arterioles appeared at 9 months follow-up, scattered among dilated ones; between 6 and 9 months after operation, ranging from 6.1 +/- 0.44% to 11.3 +/- 0.73% (P less than 0.01). In five animals with high flow, the right PA (main branch) showed patchy intimal thickening, small cystic spaces filled with mucopolysaccharides in the media, and muscular hypertrophy.     

A randomized, placebo-controlled trial of amlodipine in children with hypertension

OBJECTIVES: Evaluation of the efficacy and safety of amlodipine in hypertensive children. STUDY DESIGN: A randomized, double blinded, placebo-controlled, parallel-group, dose-ranging study was conducted at 49 centers in North and South America. The primary end point was the effect of amlodipine on systolic blood pressure (BP); secondary end points included the effect of amlodipine on diastolic BP, the effect of amlodipine as a function of dose and body size, and evaluation of safety. RESULTS: We enrolled 268 hypertensive children (mean age, 12.1 +/- 3.3 years); 84 (31.3%) had primary hypertension, and 177 (66%) were boys. Amlodipine produced significantly greater reductions in systolic BP than placebo; these were -6.9 mm Hg for 2.5 mg daily (P=.045 vs placebo) and -8.7 mm Hg for 5 mg daily (P=.005 vs placebo). The underlying cause of hypertension had no effect on the response to amlodipine. There was a significant dose-response effect of amlodipine on both systolic and diastolic BP beginning at doses > or =0.06 mg/kg per day. Systolic BP < or =95(th) percentile was achieved in 34.6% of subjects with systolic hypertension. Amlodipine was well tolerated, with just 6 children withdrawn from treatment because of drug-related adverse events. CONCLUSIONS: Amlodipine effectively lowers systolic BP in a dose-dependent manner in hypertensive children who require drug treatment.     

Blood pressure elevation associated with sleep-related breathing disorder in a community sample of white and Hispanic children: the Tucson Children's Assessment of Sleep Apnea study

BACKGROUND: The Tucson Children's Assessment of Sleep Apnea study (TuCASA) was designed to investigate the prevalence and correlates of objectively measured sleep-related breathing disorder (SBD) in preadolescent Hispanic and white children. OBJECTIVE: To describe the associations of SBD and elevation in resting blood pressure in the first 239 children enrolled in TuCASA. DESIGN: Children between the ages of 6 and 11 years (45% girls and 51% Hispanic) from elementary schools of the Tucson Unified School District were enrolled in this prospective cohort study. Resting systolic and diastolic blood pressure, sleep symptoms, and parental smoking status were obtained during evening home visits, followed by overnight unattended home polysomnography. RESULTS: The mean (SD) systolic and diastolic blood pressures were 98.4 (10.6) mm Hg and 62.0 (8.9) mm Hg, respectively. Fifteen children had hypertension. The mean (SD) respiratory disturbance index (2%), defined as the number of apneas and hypopneas per hour of sleep associated with a 2% oxygen desaturation, was 2.3 (3.8) events per hour. Factors independently associated with systolic and diastolic blood pressure elevation were obesity, sleep efficiency, and respiratory disturbance index (2%). CONCLUSIONS: In preadolescent children, elevated blood pressure is associated with SBD and obesity, as previously noted in adults. The control of obesity in childhood may be important to reduce the daytime consequences of SBD and to reduce the risks of life-long hypertension.     

Normative arm and calf blood pressure values in the newborn

Indirect BP measurement was obtained in the right upper arm in 219 healthy newborn infants with the Dinamap monitor and was compared with values obtained from the calf to establish normative BP values and to help establish a diagnosis of hypertension and coarctation of the aorta in the newborn. There were 174 Mexican-Americans (79.5%), 33 whites (15.0%), and 12 blacks (5.5%). The width of the BP cuff was selected to be 0.4 to 0.5 times the circumference of the extremities. Three supine position readings of BPs and heart rate were obtained from each site and were averaged for statistical analyses. Mean arm BP values (+/- SD) of the neonate less than 36 hours of age were 62.6 +/- 6.9/38.9 +/- 5.7 mm Hg (48.0 +/- 6.2 mm Hg). Neonates older than 36 hours had slightly but significantly (P less than .05) greater values (4 to 6 mm Hg) than did infants younger than 36 hours of age. Active neonates had values 6 to 10 mm Hg greater than quiet neonates (P less than .05). BP values in the calf obtained with the same-sized cuff were almost identical with those obtained from the arm. Differences in consecutively obtained arm and calf BPs (arm values minus calf values) were 1.1 +/- 7.7 mm Hg systolic, -0.01 +/- 6.2 mm Hg diastolic, and 0.9 +/- 6.9 mm Hg mean pressures. Mean heart rate (+/- SD) of neonates less than 36 hours of age was 129.4 +/- 13.2 beats per minute and that of neonates older than 36 hours of age was 139.4 +/- 14.1 beats per minute.(ABSTRACT TRUNCATED AT 250 WORDS)