Diastolic blood pressure variability in 24 hour-ABPM and outcomes of chronic kidney disease .

Abstract

Blood pressure variability (BPV) has been associated with increased morbidity and mortality. There are a few studies that reported worse outcomes of chronic kidney disease (CKD) with greater visit-to-visit BPV (VVV), but data with ambulatory blood pressure monitoring (ABPM) is scarce. Ambulatory hypertensive CKD (stage 2 - 4) patients (>18 years old) with complete 24hours of ABPM study (SpaceLabs), who were followed up between January 2012 and December 2016, were retrospectively analyzed for the baseline characteristics and outcomes of CKD. Coefficient of variation (CV) in diastolic blood pressure (DBP) was used as an index of BPV. Data of 191 patients (mean age 59.7±12.4 years, 54.9% males, 42.1% diabetic, mean eGFR-EPI (Chronic Kidney Disease Epidemiology Collaboration) 51.7±22.0 mL/min/1.73m2, mean follow-up 26.2±10.4 months) were available for the analysis. On multivariate linear regression analysis, greater DBP-CV was associated with slower decline in eGFR-EPI per year (B -0.648, p=0.000). Likewise, the hazard ratio (HR) for dialysis inception (occurred in 9.4%) was found significantly lower with increasing DBP-CV in unadjusted and fully adjusted Cox models (HR 0.730, 95% CI 0.618-0.861, p=0.000, and HR 0.678, 95% CI 0.526-0.874, p=0.003, respectively). These findings suggest that DBP variability in 24-hour ABPM may be a good prognostic factor for the outcomes of CKD. Further studies are needed to determine the impact of 24-hour ABPM BPV on CKD progression and its differences from VVV. .