The San Antonio Biethnic Children's Blood Pressure Study: auscultatory findings

Blood Pressure Measurement Error in Children: Lessons in Measurement Reliability

BACKGROUND AND PURPOSE

Blood pressure measurement represents the pressure exerted during heart ejection and filling. There are several ways to measure blood pressure and a valid measure is essential. The purpose of this study was to evaluate the approach to noninvasive blood pressure measurement in children.

METHODS

Blood pressure measurements were taken using the automatic Phillips MP30 monitor and compared against Welch Allyn blood pressure cuffs with Medline manual sphygmomanometers.

RESULTS

A total of 492 measurements were taken on 82 subjects, and they demonstrated comparability between automatic and manual devices.

CONCLUSIONS

Although our study indicated acceptable agreement between automatic and manual blood pressure measurement, it also revealed measurement error remains a concern, with sample size, study protocol, training, and environment all playing a role.

Blood pressure percentiles in 22,051 German children and adolescents: The PEP Family Heart Study

BACKGROUND

Strong associations between blood pressure (BP) and overweight raise the question whether overweight children (body mass index (BMI) ≥85th percentile) should be included in the normative database.

METHODS

Using the LMS (Lamda-Mu-Sigma) method, we developed age-, gender-, and height-adjusted percentile curves for systolic blood pressure (SBP) and diastolic blood pressure (DBP) at the 50th, 85th, 90th, 95th, and 97th percentiles in 22,051 German youths (18,917 normal-weight, 1,938 overweight, and 1,196 obese) aged 3-18 years from yearly cross-sectional surveys of the PEP Family Heart Study Nuremberg.

RESULTS

Among children, we found no gender differences for BP and BMI. Male adolescents are taller and heavier. The mean prevalence of hypertension and obesity is 7.3% and 5.2% among children and 7.2% and 5.8% among adolescents, respectively. The prevalence of elevated BP increased substantially by weight groups achieving 24.4% in obese females and 21.9% in obese males with odds ratios of 5.9 (95% confidence interval (CI): 5.1-7.5) and 4.3 (95% CI: 3.5-5.2), respectively. The shapes of the 10 LMS-smoothed SBP and DBP percentile curves differ substantially between gender and weight group. The normal-weight percentiles are nearly identical with the overall growth charts, but separate percentiles for overweight and obese youths provide considerably higher values, such as 148/91 vs. 136/86 mm Hg for a 17-year-old male and 136/91 vs. 123/81 mm Hg for female, respectively, at the 90th percentile.

CONCLUSIONS

Because of substantially higher BP percentiles, separate databases for overweight and obese children and adolescents are strongly recommended.

Comparison of aneroid and oscillometric blood pressure measurements in children

Limited data exist on the comparison of blood pressure (BP) measurements using aneroid and oscillometric devices. The purpose of the study was to investigate the difference in BP obtained using oscillometric and aneroid BP monitors in 9- to 10-year-old children. A total of 979 children were divided into group O, which underwent two oscillometric BP readings followed by two aneroid readings, and group A, which had BP measured in the reverse order. No significant difference was found between the mean (±standard deviation) of the two systolic BP readings obtained using the oscillometric and aneroid devices (111.5±8.6 vs 111.3±8.1 mm Hg; P=.39), whereas the mean diastolic BP was lower with the oscillometric monitor (61.5±8.0 vs 64.5±6.8 mm Hg; P<.001). A significant downward trend in BP was observed with each consecutive measurement, and agreement between the two monitors was limited. Multiple BP measurements are, therefore, recommended before the diagnosis of elevated BP or hypertension is made with either method.

The influence of birthweight on arterial blood pressure of children

BACKGROUND & AIMS

This study examined the relationship between birthweight and blood pressure in childhood.

METHODS

Prospective cohort study involving 472 Brazilian children ranging in age from 5 to 8 years. Birthweight, systolic blood pressure (SBP), diastolic blood pressure (DBP), body mass index (BMI), total cholesterol and fractions (LDL-c, HDL-c), and triglycerides were determined. Total cholesterol, LDL-c, HDL-c, and triglycerides were assessed by automated enzymatic methods. Blood pressure was measured with the HDI/Pulse Wave CR-2000 equipment. Multiple regression models were used to investigate the relationship between birthweight and SBP and DBP, controlling for the following variables: gender, age, BMI, total cholesterol, triglycerides, per capita income, and maternal education.

RESULTS

When adjusting for gender and BMI, we found a systolic blood pressure increase of 2.9 (95% CI=-5.33 to -0.56) mmHg per kilogram birthweight reduction. The unadjusted association was insignificant.

CONCLUSION

Our data suggest that low birthweight is one of the factors contributing to blood pressure elevation at early ages. A way to prevent these diseases is by implementing public policies focused on good nutrition and adequate prenatal care for pregnant women.

Inverse associations between androgens and renal function: the Young Men Cardiovascular Association (YMCA) study

BACKGROUND

Men exhibit higher risk of nondiabetic renal diseases than women. This male susceptibility to renal disease may be mediated by gender-specific factors such as sex hormones.

METHODS

We have undertaken a cross-sectional examination of associations between renal function (creatinine clearance estimated based on Cockcroft-Gault equation) and circulating levels of sex steroids (total testosterone, total estradiol, estrone, androstenedione, dehydroepiandrosterone sulfate (DHEA-S), and dihydrotestosterone) in 928 young (mean age: 18.5 +/- 1.2 years) men.

RESULTS

Both androstenedione and DHEA-S showed inverse linear associations with renal function in the crude analysis of lean men (those with body mass index (BMI) less than median). However, only DHEA-S retained its association with renal function in lean subjects after adjustment--assuming no changes in other independent variables 1 s.d. increase in DHEA-S was associated with 13%-s.d. decrease in creatinine clearance (P = 0.004). Testosterone decreased across tertiles of creatinine clearance only in the crude analysis of nonlean (BMI greater than median) subjects (P < 0.001). The adjusted regression analysis that assumed no changes in other independent variables showed that 1 s.d. increase in total testosterone was associated with 11%-s.d. decrease in creatinine clearance of nonlean men (P = 0.006). Factor analysis confirmed an inverse association of renal function with both sex steroids and a different pattern of their loadings on glomerular filtration-related factors in lean (DHEA-S) and nonlean (testosterone) subjects.

CONCLUSIONS

Our data may suggest that androgens are inversely associated with estimated renal function in apparently healthy men without history of cardiovascular disease.