Supplementary Material for: Risk Factors for Stroke in People with End-Stage Kidney Disease: A Cohort Study

Background: It is unclear how traditional cardiovascular risk factors and different treatment modalities for end-stage kidney disease (ESKD) affect stroke risk in people with ESKD. We aimed to identify the risk factors for stroke (ischemic and hemorrhagic) in people with ESKD. Methods: We conducted a retrospective cohort study using data linkage between the Australian and New Zealand Dialysis and Transplant Registry, clinical and administrative datasets. Using Cox proportional hazards models, we estimated the magnitudes of risk of hospitalization with different subtypes of strokes associated with traditional cardiovascular risk factors and ESKD treatment modalities (hemodialysis (HD), peritoneal dialysis (PD) and kidney transplantation). Results were expressed as hazard ratios (HRs) with 95% CIs. Results: A total of 10,745 people received treatment for ESKD in New South Wales, Australia, between 2000 and 2010. We observed 640 hospitalizations for stroke in 49,497 person-years of follow-up (129.4 per 10,000 person years). Some risk factors were consistent with those found in the general population, including smoking and a history of previous stroke. Other risk factors were novel for people with ESKD. Women were 85% more likely to have an intracerebral hemorrhage (HR 1.85, 95% CI 1.22-2.79) and 30% more likely to have an ischemic stroke (HR 1.30, 95% CI 1.01-1.66) than men. Compared to people on HD, people with kidney transplants had a 65% lower risk of intracerebral hemorrhage (HR 0.35, 95% CI 0.18-0.69) but a similar risk of ischemic stroke (HR 0.97, 95% CI 0.64-1.49). People on PD had a 36% higher risk of ischemic stroke (HR 1.36, 95% CI 1.05-1.76) but a similar risk of intracerebral hemorrhage compared to people on HD (HR 0.69, 95% CI 0.43-1.11). Conclusions: These findings could be used to establish reliable estimates of the risk of stroke in people with ESKD and identify those who are most likely to benefit from preventive treatments.