Introduction (Background)

Obesity epidemic in childhood has led to increased emphasis on hypertension and early cardiovascular disease. Ambulatory blood pressure monitoring (ABPM) allows for more realistic and accurate monitoring of blood pressure during normal daily activities. There are few studies correlating body mass index (BMI) percentiles and severity of ambulatory hypertension in children and adolescents. [1,2,3].

Relationship Between Systolic and Diastolic Blood Pressure Loads in ABPM and BMI Percentiles in

Children Avanikkha Elayappen MD1, Ketan N. Patel MD2, Shivaiah Balachandra MD2

1Department of Pediatrics, 2Department of Pediatric NephrologyThe University of Texas Medical Branch, Galveston, TX

•Total studied children=115; BMI groups: <94th%ile (n=26), 94–97%ile (n=31), 98-99th%ile (n=19), and >99th%ile (n=39).

•This included 30 African American, 45 Hispanic and 40 Caucasian children.

•Children with BMI below 94th%ile had mean systolic load of 34.15% and mean diastolic load of 8.65%; Children with BMI between 94 to 97 %ile had mean systolic load of 37.13 and mean diastolic load of 8.87; Children with BMI between 98 to 99 %ile had mean systolic load of 37.95 and mean diastolic load of 10.00; Children with BMI above 99th%ile had mean systolic load of 46.88% and mean diastolic load of 10.23%.

•The mean systolic and diastolic loads was highest in children with BMI above 99th%ile, but it was not statistically significant [p=0.2176 and p=0.9762 respectively (see table 1)].

•Bivariate analysis comparing blood pressure in children from different ethnicities revealed that African American children had higher mean systolic load than Hispanic and Caucasian children, but this was not statistically significant either. [p=0.2744 (see table 2)].

Aim

Our study aimed to describe the association of BMI percentiles and systolic and diastolic blood pressure loads during normal daily activities using ABPM in children and adolescents.

Conclusions•Children with increasing BMI percentiles trended towards higher systolic and diastolic loads, but our study shows that it is not statistically significant.

•Our data also suggests that there is no statistically significant difference in systolic loads among children from different racial backgrounds.

References

1. Babinska K, Kovacs L, Janko V, Dallos T, Feber J. Association between obesity and severity of ambulatory hypertension in children and adolescents. J Am Soc Hypertension. 2012 Sep-Oct;6(5):356-63.

2. Kim YK, Kim HU, Song JY. Ambulatory blood pressure monitoring and blood pressure load in obese children. Korean Circ J. 2009 Nov;39(11)):482-7.

3. Lurbe E, Alvarez V, Liao Y, et al. The impact of obesity and body fat distribution on ambulatory blood pressure in children and adolescents. Am J Hypertens. 1998 Apr;11(4 Pt 1):418-24.

Texas Pediatric Society Electronic Poster Contest

Subjects and methods

•A retrospective chart review of ABPMs (Welch Allyn 6100) was done on children between ages 7 to 18 years referred to pediatric nephrology clinic for elevated blood pressure without the diagnosis of hypertension from Jan 2011 to Oct 2013.

•All children had anthropometric data and blood pressure recorded on the date of the study and documented in electronic medical records.

•BMI was automatically calculated and recorded on BMI percentile curve.

•ABPM was placed on children with appropriate sized cuff. Standardized instructions were given to parents and children.

•Patients were divided into 4 groups based on BMI percentiles: below 94 percentile, 94 to 97 percentile, 98 to 99 percentile and above 99 percentile.

•Bivariate analysis between mean systolic and diastolic loads in ABPM and BMI percentiles was performed.

BP load

BMI <94 %ile

BMI 94-97 %ile

BMI 98-99 %ile

BMI> 99%ile P value

Mean systolic

load (SD)

34.15 (29.40)

37.13 (24.40)

37.95 (29.45)

46.87 (26.07) 0.21

Mean diastolic load (SD)

8.65 (11.15)

8.87 (11.37)

10.00 (16.42)

10.23 (13.26) 0.97

Table-2

Race

Number of

children

Mean systolic

load

Standard deviation

(SD)

African American 30 43.70 27.11

Hispanic 45 42.24 28.11

Caucasian 40 34.40 24.71

Table-1

Results

Abstract

Ambulatory blood pressure monitoring is widely used in pediatrics to identify hypertension and its complications. Previous studies correlating obesity and hypertension using ABPMs showed increasing blood pressure loads with increasing BMI. However BMI percentiles are more reliable indicators of obesity in children. Our study aimed at describing the association of BMI percentiles and systolic and diastolic blood pressure load using ABPM in children and adolescents. Retrospective analysis of ABPMs (Welch Allyn) performed on a total of 115 patients between 7 to 18 years who were referred for elevated BP without diagnosis of hypertension at our institution from Jan 2011 to Oct 2013. Patients were divided into 4 groups based on BMI percentile: <94th%ile, 94–98th%ile, 98-99th%ile, and >99th%ile. Analysis between blood pressure loads and BMI percentiles revealed higher mean systolic and diastolic loads with increasing BMI percentiles but P value was not statistically significant. Analysis of systolic loads between children from different racial backgrounds revealed higher values in African American children as compared to Hispanic and Caucasian but P value was not statistically significant.