Blood pressure-to-height ratio as a screening tool for hypertension in children

Performance of modified blood pressure-to-height ratio for diagnosis of hypertension in children: The CASPIAN-V study

This study aimed to evaluate the accuracy and performance of modified blood pressure-to-height ratio (MBPHR) for identifying high blood pressure (HBP) in a large population of children. This multicentric cross-sectional study was conducted on a nationally representative sample of 7349 Iranian students aged 7-12 years living in 30 provinces in Iran. High systolic blood pressure and diastolic blood pressure were defined according to the 2017 American Academy of Pediatrics (AAP) guidelines. The BP-to height ratio (BPHR) was calculated as BP (mmHg)/height (cm), MBPHR3 as BP (mmHg)/(height (cm) + 3 (13-age)), and MBPHR7 as BP (mmHg)/(height (cm) + 7 (13-age). The receiver-operating characteristic curve analysis was used to evaluate the performance of these three ratios for identification of HBP in children compared to the 2017 AAP guidelines as the gold standard. Mean age of participants was 12.29 ± 3.15 years and 3736 (50.8%) were girls. The prevalence of HBP was 11.9% (11.5% in boys, 12.3% in girls). The area under the curve (AUC) was higher for MSBPHR3/MDBPHR3 (0.97/0.98) than MSBPHR7/MDBPHR7 (0.96/0.97) and SBPHR/DBPHR (0.96/0.95) for identifying high Systolic and diastolic BP. The optimal cut-off points for MSBPHR3/MDBPH, MSBPHR7/MDBPHR7, and SBPHR/DBPHR were 0.76/0.50, 0.69/0.46, and 0.81/0.52 respectively. Negative predictive value was nearly perfect for three ratios (≥98%). Positive predictive value was higher for MBPHR3 (52.7%) than MBPHR7 (51.0%) and BPHR (39.8%). Overall, MBPHR3 had better performance than MBPHR7 and BPHR for identification of HBP in Iranian children and it may improve early hypertension recognition and control in primary screening.

Using blood pressure height index to define hypertension among secondary school adolescents in southwestern Uganda

Hypertension is the number one risk factor for cardiovascular diseases worldwide and yet its diagnosis among adolescents, based on blood pressure percentiles which are age, height, and sex-specific, is complex. Our study intended to determine the suitability of blood pressure height index in defining adolescent hypertension among secondary school adolescents aged 12-17 years in Mbarara municipality, southwestern Uganda. Our study used data of 485 secondary school adolescents of which 173 were boys. Receiver operating characteristic curve analysis was performed to assess the performance of systolic blood pressure height index (SBPHI) and diastolic blood pressure height index (DBPHI) for screening for adolescent prehypertension and hypertension. The optimal systolic/diastolic thresholds for defining prehypertension were 0.70/0.43 mmHg/cm in boys and 0.76/0.43 in girls. The corresponding values for hypertension were 0.78/0.43 and 0.77/0.48 mmHg/cm, respectively. The negative predictive values were much higher (all ≥ 95%) for prehypertension and hypertension, while the positive predictive value was 100% for hypertension in both sexes. In conclusion, Blood pressure height index is simple and accurate for screening for prehypertension and hypertension in adolescents aged 12-17 years hence can be used for early screening of adolescents at high risk of hypertension but not its diagnosis.

Blood pressure-to-height ratio as a screening indicator of elevated blood pressure among children and adolescents in Chongqing, China

We aimed to evaluate the performance of blood pressure-to-height ratio (BPHR) and establish their optimal thresholds for elevated blood pressure (BP) among children aged 6 to 17 years in Chongqing, China. Data were collected from 11 029 children and adolescents aged 6-17 years in 12 schools in Chongqing according to multistage stratified cluster sampling method. The gold standard for elevated BP was defined as systolic blood pressure (SBP) and/or diastolic blood pressure (DBP) ⩾95th percentile for gender, age and height. The diagnostic performance of systolic BPHR (SBPHR) and diastolic BPHR (DBPHR) to screen for elevated BP was evaluated through receiver-operating characteristic curves (including the area under the curve (AUC) and its 95% confidence interval, sensitivity and specificity). The prevalence of elevated BP in children and adolescents in Chongqing was 10.36% by SBP and/or DBP ⩾95th percentile for gender, age and height. The optimal thresholds of SBPHR/DBPHR for identifying elevated BP were 0.86/0.58 for boys and 0.85/0.57 for girls among children aged 6 to 8 years, 0.81/0.53 for boys and 0.80/0.52 for girls among children aged 9 to 11 years and 0.71/0.45 for boys and 0.72/0.47 for girls among adolescents aged 12-17 years, respectively. Across gender and the specified age groups, AUC ranged from 0.82 to 0.88, sensitivity were above 0.94 and the specificities were over 0.7. The positive predictive values ranged from 0.30 to 0.38 and the negative predictive values were ⩾0.99. BPHR, with uniform values across broad age groups (6-8, 9-11 and 12-17 years) for boys and for girls is a simple indicator to screen elevated BP in children and adolescents in Chongqing.