Kikuchi K, et al. - Given that on-line hemodiafiltration is an increasingly common alternative to chronic hemodialysis in some countries and there are now more than 60,000 patients treated with on-line hemodialfiltration in Japan, over 95% of whom use predilution on-line hemodiafiltration, researchers analyzed large-scale data on clinical outcomes with this modality. Using the Japanese Society for Dialysis Therapy Renal Data Registry database from December 31, 2012, to December 31, 2013, they created a propensity-matched cohort of 5,000 pairs of patients treated with conventional hemodialysis or predilution on-line hemodiafiltration. Findings suggested an association of predilution on-line hemodiafiltration with improved overall survival vs hemodialysis with a trend towards improved cardiovascular survival. The results obtained from this observational study suggest that predilution on-line hemodiafiltration, particularly with high substitution volumes, could improve all-cause and cardiovascular survival, but randomized controlled trials are required.