Maximum Glomerular Filtration Decline Rate is Associated with Mortality and Poor Renal Outcome in Chronic Kidney Disease Patients

Background: Glomerular filtrate rate (GFR) decline is associated with increased risk of dialysis in patients with chronic kidney disease (CKD). It is unclear whether the maximum, the minimum, or the average of GFR decline rate is associated with the risk of mortality and the initiation of renal replacement therapy (RRT). We investigated prognostic role of the maximum, the minimum, and the average of GFR decline rate in patients with CKD not yet on dialysis. Methods: Patients, enrolled in the CKD program of China Medical University Hospital between July 2004 and Aug 2013, with CKD stages 3-5 (estimated GFR [eGFR] < 60 mL/min/1.73 m(2)) not yet on dialysis were analyzed. Primary outcome was a composite of mortality and RRT. The association between 3 readings of GFR decline rate and primary outcome was analyzed using Cox proportional hazard regression. Results: We analyzed 815 patients aged 75 (interquartile range [IQR] 65-82) years with a median follow-up of 5.2 years (IQR 3.9-6.9). The maximum of eGFR decline rate was associated with the primary outcome (hazard ratio 2.19, 95% CI 1.16-4.12, p = 0.015), independent of age, gender, diabetes, cerebrovascular accident, smoking, baseline eGFR, serum albumin, calcium, urine protein/creatinine ratio, usage of renin-angiotensin system blockade. The minimum and the average of eGFR decline rate were not associated with the primary outcome. Conclusions: The maximum of GFR decline rate was associated with mortality and poor renal outcome in CKD patients, independent of other contributive confounders.