YIA 02-01 PERFORMANCE OF MODIFIED BLOOD-PRESSURE-TO-HEIGHT-RATIO FOR IDENTIFYING ELEVATED BP IN YOUNGER CHILDREN FROM CHINA AND THE USA.

OBJECTIVE: As a screening method, blood-pressure-to-height-ratio (BPHR) performed not well to identify elevated blood pressure (BP) in younger children. Our study is to compare the performance of the modified BPHR (MBPHR) and BPHR, and further to determine whether the MBPHR is superior to BPHR for screening elevated BP in Chinese and American children.

DESIGN AND METHOD: Data were obtained from the National Health and Nutrition Examination Survey in China and the USA. A total of 5463 Chinese children (boys: 52.9%) and 5050 American children (boys: 48.2 %) aged 6-12 years were included in the present study. MBPHR was calculated as BP / (height+7*(13-age)). Receiver operating characteristic (ROC) analysis was performed to establish the optimal cut-off points of systolic/diastolic MBPHR (SMBPHR/DMBPHR) and systolic/diastolic BPHR (SBPHR/DBPHR), based on sex-, age-, and height- specific BP references from the Fourth Report as the gold standard.

RESULTS: The prevalence of high BP in Chinese boys and girls, were 4.5% and 4.4%, respectively; in American boys and girls, were 2.4% and 2.3%, respectively. MBPHR owned higher AUC, sensitivity, and specificity than BPHR. The PPV of MBPHR were larger than the BPHR when identifying high normal BP in both sexes (Chinese boys: 28.0% vs. 18.8%; Chinese girls: 20.6% vs. 16.1%; American boys: 17.2% vs. 10.5%; American girls: 22.2% vs. 13.4%), as well as when identifying high BP in girls (Chinese girls: 44.1% vs. 39.6%; American girls: 36.5% vs. 25.0%). However, the PPV of MBPHR decreased compared with BPHR when identifying high BP in boys (Chinese boys: 34.3% vs. 42.8%; American boys: 24.9% vs. 44.0%).

CONCLUSIONS: MBPHR was superior to BPHR in identifying high normal BP in Chinese and American children aged 6 to 12 years, as well as in identifying high BP in girls. However, MBPHR performed poorer for identifying high BP in boys.