Reflux nephropathy and hypertension: correlation with the progression of renal damage

The aim of this study was to evaluate the relationship between blood pressure (BP), measured with ambulatory blood pressure monitoring (ABPM), and the progression of renal damage in 100 (70 females, 30 males) normotensive children with reflux nephropathy (RN). The patients, mean age of 13.5+/-5 years and almost 5 years of follow-up, were divided according to degree of RN into group A (I/II) and group B (III/IV). For each subject, 24-h systolic and diastolic BP (SBP-DBP), load (percentage of BP readings that exceeded the age- and sex-specific 95th percentile), and biochemical parameters were recorded. There was no significant difference in casual BP between the groups. The mean 24-h SBP-DBP and load were significantly higher in group B than A. There was a significant difference in creatinine (Cr) levels between the groups, and Cr correlated with BP in both groups. In group B, microalbuminuria correlated with ambulatory BP, and plasma renin activity failed to decrease with chronological age. Elevated load was shown in 8 of 50 patients in group A and in 21 of 50 in group B. In 3 of 12 patients of group B, with increased load BP, left ventricular geometry, by integrated backscatter, was abnormal. ABPM was useful in selected children at risk of hypertension.