Background:
Pre-hypertension and hypertension in childhood are defined by sex-, age- and height-specific 90th (or ≥120/80 mmHg) and 95th percentiles of blood pressure (BP), respectively, by the 2004 Fourth Report. However, these cut-offs are complex and cumbersome for use. This study assessed the performance of a simplified BP definition to predict adult hypertension and subclinical cardiovascular disease.
Methods:
The longitudinal cohort consisted of 1,225 adults (530 males, aged 26.3–47.7 years) from the Bogalusa Heart Study, with 27.1 years follow-up since childhood. We used 110/70 and 120/80 mmHg for children (age 6-11 years), and 120/80 and 130/85 mmHg for adolescents (age 12-17 years) as the simplified definitions of childhood pre-hypertension and hypertension, respectively, to compare with the complex definitions. Adult carotid intima-media thickness (CIMT), pulse wave velocity (PWV), and left ventricular mass were measured using digital ultrasound instruments. High CIMT was defined as being above the age-, gender- and race-specific 80th percentile, high PWV as being above the age-, gender-, race- and heart rate-specific 80th percentile and left ventricular hypertrophy as >46.7 g/m
2.7
in women and >49.2 g/m
2.7
in men.
Results:
Compared to normal BP, childhood hypertensives diagnosed by the simplified definition (4.1%, 50/1,225) and the complex definition (4.8%, 59/1,225) were both at higher risk of adult hypertension with hazard ratio=3.1 (95% confidence interval=1.8-5.3) by the simplified definition and 3.2 (2.0-5.0) by the complex definition, high PWV with 3.5 (1.7-7.1) and 2.2 (1.2-4.1), high CIMT with 3.1 (1.7-5.6) and 2.0 (1.2-3.6), and left ventricular hypertrophy with 3.4 (1.7-6.8) and 3.0 (1.6-5.6). The prediction using the two childhood BP definitions for adult hypertension and subclinical cardiovascular disease was also assessed by reclassification or receiver operating characteristic curve analyses.
Conclusions:
The simplified childhood BP definition predicts the risk of adult hypertension and subclinical cardiovascular disease equally as the complex definition does. The simplified pediatric BP cut-offs could be easier to use for screening children at high risk and for targeting early life interventions to reduce the risk of developing cardiovascular disease in later life.