Clinical Outcomes and Costs of 4-Week Versus 6-Week Bloodwork for Patients on Hemodialysis

Rationale \& Objective: Routine bloodwork for patients on hemodialysis has both financial and opportunity costs, but there is little data on how the frequency of measurement affects patient outcomes. Our objective was to determine the effect of changing from routine bloodwork at four-week intervals to six-week intervals on the achievement of anemia and chronic kidney disease-mineral and bone disorder (CKD-MBD) targets. Study Design: Retrospective interrupted time series from June 1, 2012 to December 31, 2015. Setting \& Participants: Tertiary hospital in Ontario, Canada, that provides hemodialysis to 350-400 adult patients. Quality Improvement Activities: Institution-wide switch of routine bloodwork from four-week intervals to six-week intervals on March 24, 2014. Outcomes: Proportion of patients who achieved recommended hemoglobin and phosphate targets. In a 252-day sub-analysis, we also calculated the cost-savings attributable to a change in laboratory testing frequency for hemoglobin, ferritin, iron saturation, calcium, and phosphate. Analytical Approach: Statistical Process Control to analyze variation in the clinical outcomes.