Abstract 105: Blood Pressure Variation and Renal Functional Changes in Chronic Renal Insufficiency Patients With or Without Diabetes in a Large Cohort Study

Abstract

Hypertension and diabetes mellitus (DM) are leading causes for chronic kidney disease (CKD). Regardless, interplays of blood pressure, diabetes status, and renal function are largely unknown. We hypothesize that systolic blood pressure (SBP) variation affects renal function disproportionally in CKD patients with or without DM. Data from the Chronic Renal Insufficiency Cohort Study (CRIC) that enrolled 3,939 participants with CKD aged 21-74 years and followed between 2003-2013 were used. SBP was categorized into 3 levels over time: ≤120 as low, 121-140 as medium, and >141 as high, and relationship of these SBP levels with four renal indices in DM versus non-DM patients was analyzed using Generalized Estimating Equation (GEE) and Curve Fitting methods. Regression results showed that after controlling for confounding factors, for each category of low, medium or high SBP, the predicted eGFR was 4.5, 3.4 and 3.1 units lower for DM comparing to non-DM patients (p<0.01), respectively. Similarly, albuminuria was 0.19, 0.54 and 0.76 units higher (p<0.01), serum creatinine was 0.43, 0.33 and 0.29 units higher (p<0.01), and urinary creatinine was 5.24, 6.27 and 7.37 units lower (p<0.01) with DM comparing to without DM for low to high SBP, respectively. Curve Fitting results showed that slopes of curves for eGFR at all SBP levels were similar for DM and non-DM patients. In contrast, the slopes for albuminuria curve in all SBP levels was much steeper for DM comparing to non-DM patients. Thus, while renal function is worse in CKD patients with DM comparing to non-DM at any given SBP, lowering blood pressure may improve renal function with bigger beneficial effects on albuminuria in CKD patients with DM.