Objective: From the end of 1990s, ambulatory blood pressure monitoring (ABPM), which measures ambulatory blood pressure (ABP) during a whole 24 hours, has been applied. However, there are few studies on the use of ABPM in children with kidney disease, especially those whose renal function is normal or mildly impaired in both China and abroad. This study aimed to explore the characteristics of ABP in patients with common pediatric kidney diseases.
Methods: Totally 33 patients (21 boys and 12 girls) hospitalized in our hospital with kidney diseases aged from 5 - 16 yrs from February 2005 to January 2006 were enrolled; 28 cases (85%) had normal renal function [Ccr > or = 90 mmol/(Lx1.73 m2)]. None of them were taking anti-hypertensive drugs during the monitoring. Twenty-four-hour ABP monitoring was performed by using Welch Allyn ABPM 6100 in the patients. ABPM recordings of 1141 healthy children performed in Germany in 1997 was used as the normal reference data, which was the largest pediatric study and was most commonly used in the world up to now.
Results: The incidence of nocturnal hypertension was significantly higher than that of diurnal hypertension (P < 0.01); nocturnal systolic/diastolic blood pressure load (29.1 +/- 34.5)%/(24.9 +/- 34.3)% and index (0.95 +/- 0.11)/(0.90 +/- 0.18) were significantly higher than diurnal systolic/diastolic blood pressure load (12.9 +/- 23.6%/9.3 +/- 19.1%) and index (0.88 +/- 0.09)/(0.77 +/- 0.12) (P < 0.01); nocturnal systolic/diastolic dipping rate (7.3 +/- 5.3)%/(10.5 +/- 10.6)% in the patients was significantly lower than that in the healthy children (13 +/- 6)%/(23 +/- 9)% (P < 0.01); the incidence of non-dipper in 33 patients was 72.7%, even with the same incidence in patients with normal blood pressure. Five cases had elevated CBP whose ABP were also elevated; while among the 28 cases with normal CBP, 6 cases were found to have elevated ABP.
Conclusions: ABPM can detect the nocturnal hypertension and abnormal rhythm of blood pressure during 24-hour in patients with pediatric nephropathy. ABPM can also disclose masked hypertension, thereby warrant to follow-up and start earlier intervention.