Blood pressure-to-height ratio as a screening measure for identifying children with hypertension

Abstract

The present study evaluated the feasibility and accuracy of the blood pressure-to-height ratio (BPHR) and proposed the optimal thresholds of BPHR for identifying hypertension in Han children aged 7-12 years. In 2011, anthropometric measurements were assessed in a cross-sectional population-based study of 1,352 Han children aged 7-12 years. Hypertension was defined according to the 2004 National High Blood Pressure Education Program Working Group definition (as gold standard). The following equations for BPHR were used: systolic blood pressure-to-height ratio (SBPHR) = SBP (mmHg)/height (cm) and diastolic blood pressure-to-height ratio (DBPHR) = DBP (mmHg)/height (cm). Receiver operating characteristic curve analyses were performed to assess the accuracy of SBPHR and DBPHR as diagnostic tests for elevated SBP and DBP, respectively. After the cutoff points were determined, hypertension was defined by SBPHR/DBPHR (new standard), and the sensitivity and specificity were calculated. The accuracy of SBPHR and DBPHR (assessed by area under the curve) for identifying elevated SBP and DBP was over 0.85 (0.946-1.000). SBPHR cutoff values for elevated SBP were calculated to be 0.76-0.88 mmHg/cm in boys and 0.78-0.90 mmHg/cm in girls. DBPHR cutoff values for elevated DBP were calculated to be 0.51-0.60 mmHg/cm in boys and 0.51-0.58 mmHg/cm in girls. When hypertension was defined by BPHR, the sensitivities were 100 % in boys and 95.0 % in girls. The specificity was 94.3 % in boys and 96.8 % in girls. BPHR is a simple, inexpensive, and accurate index for screening hypertension in Han children.