15-YEAR FOLLOW-UP OF RENIN AND BLOOD-PRESSURE IN REFLUX NEPHROPATHY

Background Beginning in 1978 a cohort of patients with reflux nephropa thy first seen at a London Children's hospital have had 5-yearly follo w-ups. This is the fourth (15-year) report from that series. Methods O f the original 100 normotensive children with reflux nephropathy 78 we re traced for the 15-year study in 1994. Five patients were excluded b ecause of nephrectomy, ten for other reasons, and eight refused to tak e part, leaving 55. 26 were on oral contraceptives. Supine blood press ure and plasma renin activity (PRA) were measured, and daily sodium ex cretion was assessed on a sample of overnight urine. Findings Of the 5 5 patients (15 male, 40 female, median age 27 years, range 20-31), fiv e had systolic and two had diastolic hypertension. Compared with the 1 0-year (1988) follow-up there was no change in blood pressure standard deviation scores (SDS) in this cohort. PRA showed an increasing disso ciation from controls after 15 years of age and was significantly abov e that of controls by age 25. Exclusion of the patients on oral contra ceptives did not significantly alter the results. The PRA values in 19 88 were not individually predictive of the development of hypertension over the ensuing 5 years. Interpretation Previously, in the long-term study of reflux nephropathy, blood pressure SDS had progressively inc reased with age. By 15 years blood pressure had levelled out and the P RA, though raised, did not predict the development of hypertension. Or al contraceptive use did not significantly modify the results.