Relationship Between the Brain Natriuretic Peptide (BNP) Level and Remission of Diabetic Nephropathy with Microalbuminuria: A 3-Year Follow-Up Study

The aim of the study was to examine the relationship between the brain natriuretic peptide (BNP) level and progression or remission of diabetic nephropathy with microalbuminuria for 3 years. The subjects were 100 Japanese type 2 diabetes mellitus outpatients with microalbuminuria. Associations between metabolic parameters at baseline [HbA1c, systolic blood pressure (SBP), urine albumin-creatinine ratio (ACR), estimated glomerular filtration rate (eGFR), and BNP] and the progression or remission of diabetic nephropathy were examined for 3 years. A total of 83 patients were examined at the end of the 3-year period, including 17 with remission to normoalbuminuria, 47 with continuing microalbuminuria, and 19 with progression to macroalbuminuria. HbA1c, ACR, and BNP differed significantly among the 3 groups (p = 0.024, p < 0.001, p = 0.002, respectively). Among baseline factors, HbA1c and BNP were significant predictors of the percentage increase in ACR for 3 years in multiple linear regression analysis (beta = 0.259, p = 0.02; beta = 0.299, p = 0.007, respectively). In multivariate logistic regression analysis, HbA1c and ACR were independently associated with progression of diabetic nephropathy (p = 0.008, p = 0.023, respectively), and ACR and BNP were independently associated with remission of diabetic nephropathy (p = 0.029, p = 0.012, respectively). ROC curve analysis gave a cutoff value for BNP of 14.9 pg/ml for prediction of remission of diabetic nephropathy (p = 0.016). The BNP level has a relationship with diabetic nephropathy and a low BNP level predicts remission of diabetic nephropathy. Therefore, monitoring of BNP can play an important role in management of diabetic nephropathy.