We found that CD14(++)CD16(+) monocytes were independently associated with CV events in non-dialysis CKD patients. Our results support the notion that CD16(+) monocytes rather than CD16(-) monocytes are involved in human atherosclerosis.

Migration of monocytes into the vessel wall contributes to the onset and progression of atherosclerosis. Because monocytes are a heterogeneous population, we determined potential associations between monocyte subsets and cardiovascular events in a prospective cohort of 94 dialysis patients followed for 35 months. The incidence of cardiovascular events and death measured by Kaplan-Meier plots and flow cytometric analysis of monocyte subsets showed that total leukocyte and monocyte numbers failed to predict event-free survival. Among monocyte subsets, a high CD14(++)CD16(+) monocyte number was associated with higher rates of cardiovascular events and death. In a multivariate proportional hazards model adjusted for classical cardiovascular risk factors, patients with CD14(++)CD16(+) monocyte numbers in the top quartile were at higher risk of cardiovascular events and death compared to patients in the lowest quartile. Our study suggests that the number of CD14(++)CD16(+) monocytes was independently associated with cardiovascular events and death in a high-risk population of dialysis patients.

Elevated FGF-23 plasma levels predict cardiovascular events in CKD patients not on dialysis therapy. This finding complements two recent cohort studies in which incident and prevalent haemodialysis patients with highest FGF-23 levels had worst survival. Lowering FGF-23 levels (e.g. by oral phosphate binder medication) could emerge as a promising new therapeutic option to reduce cardiovascular morbidity in CKD patients.

In patients suffering from CKD, intrarenal resistance indices are independently associated with cardiovascular risk score and systemic vascular disease as well as with aetiology and stage of CKD. This may explain their strong association with both impaired renal outcome and death.

The finding of increased ACE expression on monocytes of dialysis patients with cardiovascular disease links monocytes to the activated renin-angiotensin system. ACE expression was found highest among CD14++16+ monocytes, which is in accordance with a prominent role of these proinflammatory cells in atherogenesis.