Background: In diabetic patients with renal artery arteriosclerosis (RAAS), the factors associated with a greater risk for cardiovascular-renal events (CVREs) remain unclear: the decline in estimated glomerular filtration rate (eGFR) caused by RAAS or the advance of arteriosclerosis that causes RAAS. Hence, the features to determine which best predicts the onset of CVREs in such patients were compared.
Methods and Results: The renal arteries of 162 type 2 diabetes patients were assessed by using magnetic resonance angiography (RAAS diagnosed as arteriosclerotic stenosis >= 50%) and they were studied longitudinally over 7 years. The influence of the presence/absence of RAAS, a decline in eGFR, clinical factors, surrogate arteriosclerotic markers and ischemic markers on patient's CVREs were assessed. A Cox regression analysis showed the detection of RAAS to be an independent risk factor for CVREs (bilateral RAAS was an extremely strong risk factor for the development of CVREs within 1,000 days), as was the decline in eGFR in a logistic regression analysis; the latter being a more powerful risk factor for CVREs. A multiple regression analysis revealed angiopoietin-2, a marker of ischemia, to be a risk factor for the decline in eGFR.
Conclusions: A decline in renal function but not the renal arterial stenotic lesion itself appears to be associated with an increased incidence of CVREs in type 2 diabetic patients with RAAS.