Proteinuria as a predictor of renal functional outcome after revascularization in atherosclerotic renovascular disease (ARVD)

Backround: Renal revascularization is performed in 16 of newly diagnosed patients with atherosclerotic renovascular disease (ARVD). Although there may be some improvement in hypertension control as a result of intervention, renal functional outcomes are known to vary. Pre-existing renal parenchymal injury, as manifested by proteinuria, is associated with poor functional outcome in conservatively managed ARVD patients, but this association has not been investigated in patients undergoing revascularization. Methods: Retrospective case note review of 83 ARVD patients who underwent renal revascularization in four centres within a renal network between 1998 and 2003 was undertaken. Amongst other parameters, baseline proteinuria was correlated with renal functional outcome post revascularization. Renal functional outcome was determined over a mean follow up of 22 months by rate of change of estimated glomerular filtration rate (eGFR) over time. Results: Univariate analysis showed that proteinuria 0.6 g/day was the only significant predictor of poor outcome after revascularization. The relationship persisted with multivariate analysis, and linear regression showed a correlation between baseline proteinuria and decline in eGFR with time (r(2) 0.058, P 0.039). Conclusion: This study confirms that prior renal parenchymal injury, here reflected by proteinuria at baseline, is a major arbiter of renal functional outcome after renal revascularization in ARVD.