Accuracy of blood pressure-to-height ratio for screening elevated blood pressure in Egyptian adolescents aged 11-15 years

Abstract

Objective: This study aims to validate measures of blood pressure-to-height ratios (BPHR) in screening for elevated blood pressure (EBP) in a sample of the Egyptian adolescence aged 11-15 years.Methods: A cross sectional study was conducted on a sample of 1707 students aged 11-15 years. Elevated blood pressure was defined according to the international gold standard definition. Systolic and diastolic BPHR (SBPHR and DBPHR) were calculated for boys and girls, and their ability to identify EBP has been determined by the area under the curve of the receiver operator characteristic curves. Sex-specific optimal cut-off points were determined along the curve, and their sensitivity, specificity, positive and negative predictive values (PPVs, and NPVs), and positive and negative likelihood ratios (LR+, and LR-) were estimated. Results: The accuracy of SBPHR and DBPHR in diagnosing EBP in both sexes ranged from 0.906 to 0.981. For diagnosing systolic and diastolic pre-hypertension (pre-HTN), the optimal cut-off points were: 0.69, 0.44 in boys, and 0.71, 0.46 in girls respectively. For diagnosing systolic and diastolic hypertension (HTN), the corresponding values were 0.75, 0.49, and 0.75, 0.50 respectively. These determined cut-off points revealed high sensitivity (0.88-1.00), moderate to high specificity (0.77-0.95), high NPVs (0.99-1.00), low PPVs (0.15-0.38), and variable likelihood ratio values (LR+: 3.8-20.0, and LR-: 0.0-.36.0).Conclusion: Blood pressure-to-height ratios are considered of high accuracy in identifying pre-HTN and HTN in the Egyptian adolescents aged 11-15 years. Further research is needed for examining the performance of the BPHR in other age groups, in high risk adolescents, and for examining the performance of modified ratios.