DIURNAL BLOOD-PRESSURE PATTERNS IN NORMOTENSIVE AND HYPERTENSIVE CHILDREN AND ADOLESCENTS

As abnormalities in diurnal ambulatory blood pressure (BP) have been a ssociated with hypertensive target organ damage in adults, we investig ated the diurnal systolic BP (SBP) and diastolic BP (DBP) patterns of 54 normotensive children, age 13.4 +/- 3.0 years, and 45 untreated bor derline and mildly hypertensive children, age 14.4 +/- 2.6 years. Subj ects wore the SpaceLabs 90207 ambulatory BP monitor for 24 h. BP was m easured q 15 min from 08.00-21.00 h then q 30 min from 21.00-08.00 h; Nocturnal BP fall, the night-day ratio and cusum derived measures were calculated from time-weighted daytime and night-time SBP and DBP. The groups were compared using analysis of covariance with adjustment for age, race, gender and body mass index. The influence of age, gender a nd race on the diurnal BP profile was also examined. Nocturnal SBP fal l was greater in hypertensive compared to normotensive subjects (17.1 +/- 6.7 vs 14.6 +/- 7.1 mmHg; unadjusted mean +/- s.d., P = 0.022). No rmotensive and hypertensive groups did not differ in nocturnal DBP fal l or SEP or DBP night-day ratio. Race appeared to influence the diurna l BP pattern as black subjects had less nocturnal SBP fall (12.9 +/- 6 .9 vs 17.1 +/- 6.5 mm Hg; P < 0.005) and a higher night-day SBP ratio (90.1 +/- 5.3 vs 86.7 +/- 4.6%; P < 0.005) than white subjects. In con clusion, hypertensive children and adolescents have a similar diurnal BP pattern as their normotensive counterparts, except that the entire BP profile is shifted upward with a greater absolute fall in SEP at ni ght. Race also appears to influence the diurnal BP profile of normoten sive and hypertensive children and adolescents.