The importance of proteinuria and prior cardiovascular disease in all major clinical outcomes of atherosclerotic renovascular disease - a single-center observational study.

BACKGROUND: Identification of patients at risk of developing adverse events would enable aggressive medical therapy and possibly targeted revascularization. The aim of this study is to characterize the determinants of long-term outcomes in atherosclerotic renovascular disease (ARVD).

METHODS: Patients with a radiological diagnosis of ARVD were recruited into this single-center prospective cohort study between 1986 and 2014. Data collected included baseline co-morbid conditions, annualized prescribed medications and laboratory data (serum creatinine [υmol/L], proteinuria [g/24 h]). Multivariable Cox regression analysis was used to explore association with these end-points: death, end-stage kidney disease (ESKD), cardiovascular event (CVE) and the first of any of these events.

RESULTS: A total of 872 patients were recruited into this study. However, 42 patients were excluded due to missing baseline data and hence case records for 830 patients were reviewed. Over median follow-up of 57.1 months (interquartile range: 21.7-96.9), incidence per 100 patient years of death, ESKD, CVE and any event was 13.5, 4.2, 8.9 and 21.0 respectively. Macrovascular disease (MVD), congestive heart failure (CHF), flash pulmonary oedema (FPE) and greater proteinuria at baseline were individually associated with increased risk for all end-points in multivariable analysis (Death: MVD -HR 1.24 [95% CI 1.02-1.50]; CHF -HR 1.33 [95% CI 1.08-1.64]; FPE - HR 2.10 [95% CI 1.50-2.92]; proteinuria - HR 1.14 [95% CI 1.08-1.20]). Higher estimated glomerular filtration rate at time of diagnosis was significantly associated with reduced risk of all end-points (Death: HR 0.92 [95% CI 0.89-0.94])., Administration of statins and renin angiotensin blockade (RAB) at baseline were also associated with reduced adverse events, especially death (RAB: HR 0.83 [95% CI 0.70-0.98]; statins: HR 0.79 [95% CI 0.66-.94]) and ESKD (RAB: HR 0.84 [95% CI 0.71-1.00]; statins: HR 0.79 [95% CI 0.66-0.93]). Revascularization was associated with reduced risk of death (HR 0.65 [95% CI 0.51-0.83]) and ESKD (HR 0.59 [95% CI 0.46-0.76]).

CONCLUSION: All patients with ARVD require intensive vascular protection therapy to help mitigate systemic atherosclerosis, optimize cardiovascular risk and improve clinical outcomes. More effort is required to identify the minority of patients who may benefit from revascularization.