Different circadian patterns of arterial stiffness are responsible for increased cardiovascular mortality in hemodialyzed patients.

We hypothesized that volume changes during 48-h are associated with different circadian patterns of arterial stiffness on non-dialysis day compared to dialysis day and that the night-time increase of arterial stiffness is associated with higher mortality. The patients whose night-time mean pulse wave velocity levels drop or rise more than 0.5 m/s compared with the day-time period were defined as pulse wave velocity dippers and risers. The patients whose night-time mean augmentation index drop or rise more than 10% compared with the day-time period were defined as augmentation index dippers and risers. There was significantly higher number of patients with dipping and rising pattern of augmentation index and pulse wave velocity on non-dialysis day when compared to dialysis day. On the non-dialysis day both nocturnal augmentation index and pulse wave velocity levels were higher in deceased group with significantly higher number of augmentation index and pulse wave velocity dippers when compared to survived patients. In the linear regression model, the strongest association of survival was with augmentation index and pulse wave velocity risers on the non-dialysis day. On logistic regression only pulse wave velocity rising pattern on non-dialysis day had increased HR of 1.78 for cardiovascular mortality. The present study is the first which analyzed circadian patterns of arterial stiffness in patients on hemodialysis and compared their impact on cardiovascular mortality. A significantly greater number of patients had an augmentation index and pulse wave velocity rising pattern in the deceased group compared to the survived group of patients. Survival had the strongest association with augmentation index and pulse wave velocity risers on the non-dialysis day.