The IDEAL Trial in Australia and New Zealand: Clinical and Economic Impact.

BACKGROUND:The impact of research findings on clinical practice usually remains uncertain and unmeasured. To address this problem, we examined the long-term clinical and economic impact of the Initiating Dialysis Early and Late (IDEAL) trial using data from the Australia and New Zealand Dialysis and Transplant Registry.METHODS:We performed a registry-based study including all incident adult dialysis patients in Australia and New Zealand from July 2000 to June 2018. A piecewise linear regression model was used to examine differences in mean estimated glomerular filtration rate (eGFR) at dialysis commencement for the years prior to (2000-2010) and following (2010-2018) publication of the IDEAL trial results. The return on investment (ROI) was calculated using the total cost of performing the IDEAL trial and the cost or savings accruing in Australia and New Zealand from changes in dialysis initiation practice.RESULTS:From July 2000 to June 2010, mean eGFR at dialysis commencement increased at a rate of 0.21 mL/min/1.73 m2/year [95% confidence interval (CI) 0.19-0.23]. After the IDEAL trial results were published, mean eGFR at dialysis commencement did not show any temporal change [-0.01 mL/min/1.73 m2/year (95% CI -0.03-0.01)]. The ROI of the IDEAL trial was AU$35.70/AU$1 spent, an estimated savings to the Australian and New Zealand health systems of up to AU$84 million/year.CONCLUSIONS:The previous trend to higher eGFR at dialysis commencement changed following publication of the IDEAL trial results to a steady eGFR that has continued for a decade, avoiding unnecessary dialysis treatments and accruing savings to the Australian and New Zealand health systems.