K S MINAS1, G WONG2,3,4, W HON LIM1,5
1Sir Charles Gairdner Hospital, Perth, Australia, 2Sydney School of Public Health, University of Sydney, Sydney, Australia, 3Centre for Kidney Research, The Children’s Hospital at Westmead, Sydney, Australia, 4Centre for Transplant and Renal Research, Westmead Hospital, Sydney, Australia, 5Medical School, University of Western Australia, Perth, Australia
Aim: To examine the association between sex and risk of all-cause and cardiovascular disease (CVD) mortality in incident dialysis patients.
Background: Men experience a higher risk of death during the pre-dialysis CKD stage, but survival are largely comparable between men and women when they reach kidney failure.
Methods: Using data from the Australia and New Zealand Dialysis and Transplant (ANZDATA) registry, we included all incident patients who had initiated dialysis in Australia and New Zealand between 1998 and 2018. The associations between sex, all-cause and CVD mortality were examined using adjusted Cox regression and competing risk models.
Results: Of 55,153 incident dialysis patients, 30347 (55%) died, with 10479 (19%) attributed to CVD mortality . CVD deaths and withdrawal were the predominant cause of death in men and women respectively. In the first 5 years post-dialysis initiation, females were more likely to die compared to males with adjusted HR of 1.06 (95% confidence intervals [95% CI] 1.02-1.09), but not after 5 years after initiation of dialysis (adjusted HR 0.97, 95% CI 0.93-1.02). Compared to men, women were less likely to experience CVD mortality for both time-periods, with adjusted HR of 0.89 (95% CI 0.85-0.93) and 0.81 (95% CI 0.74-0.88) for <5 years and ≥5 years post-dialysis initiation. The estimates for the competing risk models were similar for all-cause and CVD mortality.
Conclusions: Despite the lower risk of CVD mortality experienced by female patients with kidney failure, there is an excess risk of early all-cause mortality in the first 5 years post-dialysis initiation. The reason for this is unclear but may reflect a higher likelihood of withdrawal, which needs to be further explored.
Kimberley Minas is a nephrology and general medicine advanced trainee in Western Australia. Her prior work in biostatistics and public health has led to an interest in using research to improve the health outcomes of people living with kidney disease.