H CHEIKH HASSAN 1,2, K MURALI 1, M LONERGAN 1, M BORLACE M3, N BOUDVILLE 4, D JOHNSON D5,6,7, J CHEN 1,2
1Department of Nephrology, Wollongong Hospital, Wollongong, Australia, 2University of Wollongong, Wollongong, Australia, 3Central Northern Adelaide Renal and Transplantation Service, Royal Adelaide Hospital, Adelaide, Australia, 4Medical School, University of Western Australia, , Australia, 5Department of Nephrology, Princess Alexandra Hospital, Australia, 6Australasian Kidney Trials Network, University of Queensland, Brisbane, Australia, 7Translational Research Institute, Brisbane, Australia
Aim: Examine cardiovascular mortality risk following a peritoneal dialysis (PD) peritonitis episode.
Background: Patients receiving PD have an increased cardiovascular mortality risk. Infection is a known cardiovascular risk factor, and peritonitis is a common infection in patients on PD
Methods: Using the Australian and New Zealand Dialysis and Transplant (ANZDATA) Registry, we examined the association between peritonitis and cardiovascular mortality in incident adult PD patients (October 2003-December 2019). A Jointpoint model was used to evaluate changes in annual peritonitis rates over time. Adjusted competing risk analysis was used to calculate sub distribution hazards ratios (SHR).
Results: Of 9,699 patients followed over 32,455 patient-years, 4,353 (45%) experienced peritonitis (0.27 episodes per patient-year). Crude cardiovascular death rates were 61.9 per 1000 patient-years in patients who experienced peritonitis and 34.9 per 1000 patients-years in patients who did not experience peritonitis (overall 45.6 per 1000 patient-years). Compared to patients with no peritonitis, those with a peritonitis episode had a significantly increased risk of cardiovascular mortality (SHR 1.50, 95% CI 1.37- 1.64).
Peritonitis rate decreased by -4.7% per year during the study period (P<0.05) with a significant reduction during 2004-2011 (-8.0% per year, P<0.05) and a non-significant reduction during 2012-2019 (-2.4% per year, P=0.1). Compared to patients initiating PD between 2003-2011, the risk of cardiovascular mortality was significantly decreased in patients initiating PD between 2012-2019 (SHR 0.59, 95%CI 0.49- 0.69).
Conclusion:Peritonitis is a significant risk factor for cardiovascular mortality in the PD population. Australian peritonitis rates decreased over time, with a corresponding decrease in the risk of cardiovascular mortality. While declines in cardiovascular mortality were likely multifactorial in origin, the drive to reduce peritonitis rates is an important consideration.
Dr Hicham Cheikh Hassan is a Nephrologist working in the Illawarra Shoalhaven Local Health District. His research interests include clinical epidemiology, infection and cardiovascular health in the renal population.