Online haemodiafiltration and all-cause mortality: how fragile are the results of the studies published so far?

To the Editor, Cardiovascular disease is a major cause of morbidity in patients on dialysis and accounts for almost 50% of deaths in these patients [1]. Although this high mortality is attributable to many reasons, the limited clearance of potentially harmful middle molecules through standard haemodialysis (HD) may be a contributor. Online haemodiafiltration (HDF) augments the clearance of middle molecular weight uraemic toxins through convective clearance while standard HD treatment is primarily based on diffusion [1].