A new index to simplify the screening of hypertension in overweight or obese youth.
BACKGROUND AND AIMS
Hypertension (HTH) is a frequent complication in pediatric obesity. To simplify the screening of HTH in overweight/obese (Ow/Ob) youth, we compared the performance of a new index (High Blood Pressure index, HBPi) with respect to the standard criteria of the IV Report [systolic BP (SBP) and/or diastolic BP (DBP) ≥95th percentile for age, gender and height]. We also compared the performance of HBPi with other simplified indices such as the BP/height ratio and the absolute height-specific BP thresholds. Ten pediatrics' outpatient centers participating in the "CARdiometabolic risk factors in ITALY study" provided medical records of 4225 Ow/Ob children and adolescents (age 6-16 years).


METHODS AND RESULTS
Centers were divided into two groups: training set (TS) (n = 2204 participants) and validation set (VS) (n = 2021 participants). The simplified HBPi (mmHg) was: (SBP/2 + DBP/10) - age + (1 × female gender). In the TS, a HBPi value ≥57 mmHg in both children and adolescents had high sensitivity (0.89), specificity (0.97), positive (0.89) and negative (0.97) predictive values in classifying youth at high risk of HTN compared with the IV Report. In the VS, the HBPi showed a better performance than high levels of BP/height ratio and height-specific BP thresholds in classifying individuals at risk of HTN: area under curves 0.95 (0.93-0.96), 0.80 (0.78-0.82), 0.76 (0.74-0.79), respectively; specificities 0.95 (0.94-0.96), 0.69 (0.67-0.72), 0.60 (0.57-0.62), respectively.


CONCLUSIONS
HBPi, combining SBP and DBP, gender and age, may help pediatricians to implement HTN screening in Ow/Ob youth.