Incidence rate of cardiovascular events is comparable between normoalbuminuric and albuminuric diabetic patients with chronic kidney disease

Abstract

Background: Diabetic kidney disease (DKD) develops microalbuminuria (MiA), and gradually progresses to overt proteinuria (MA) coincided with renal insufficiency. However, several recent studies have demonstrated that 20-40% of patients with DKD are normo- to micro-albuminuric despite their decreased renal function. In this study, the renal and cardiovascular outcomes in normo-, micro-, or macro-albuminuric diabetic patients with renal insufficiency were investigated.Methods: Data from 1,136 diabetic patients with chronic kidney disease (CKD) stage III or IV between 2007 and 2009 were retrospectively collected. Subjects were divided into normoalbuminuria (NA), MiA, and MA group. New-onset cardiovascular events or death, and renal outcomes defined as end-stage renal disease (ESRD) or a 50% decline of glomerular filtration rate (GFR) were evaluated during the follow-up period. Cox proportional hazard analysis was performed to evaluate the association between albuminuria and the clinical outcomes.Results: The mean age was 61.7 ± 10.1 years and the mean estimated GFR was 38.9 ml/min/1.73m2. Among 1,136 patients, 255 patients (22.4%) were NA, 275 patients (24.2%) were MiA, and 606 patients (53.3%) were in MA group. During a mean follow-up duration of 44 months, the development of cardiovascular disease was not different among the three groups (P = 0.67). However, progression to ESRD or a 50% decline of GFR was significantly more prevalent in the MA group compared to the NA and MiA groups (P < 0.001). Multivariate Cox analysis revealed that macroalbuminuria and estimated GFR were independent predictors of renal outcomes. However, the amount of albuminuria was not associated with cardiovascular outcomes in the study population.Conclusion: There are significant and substantial differences in the clinical outcomes of diabetic patients with renal dysfunction according to

the degree of albuminuria. In particular, cardiovascular outcomes were comparable while renal outcomes were significantly different depending on the amount of albuminuria in DKD patients with renal insufficiency.