The present invention relates to high cut-off hemodialysis membranes for the treatment of chronic hemodialysis (CHD) patients, with the potential to improve long-term survival of these patients by reducing the risk of cardiovascular disease, through down-regulation of monocyte activation in the blood. Monocytes are the major circulating blood cells involved in the progression of cardiovascular disease. High cut-off hemodialysis in chronic dialysis patients results in a sustained decrease in expression of monocyte cell-surface proteins that direct the movement of these cells from the blood to the walls of blood vessels, where they promote the progression of arterial disease (atherosclerosis) that leads to cardiovascular disease (CVD); heart disease, strokes and peripheral vascular disease.