A JEYARUBAN1,2,3, WE HOY1,2, A CAMERON1,2, HG HEALY1,2,3, J ZHANG1,2, A MALLETT1,2,3
1CKD.QLD and NHMRC CKD.CRE, Brisbane, Australia, 2Faculty of Medicine, The University of Queensland, Herston, Australia, 3Kidney Health Service, Royal Brisbane and Women’s Hospital, Brisbane, Australia
Aim: To investigate whether incident cardiovascular events (CVE) are associated with mortality in a prevalent chronic kidney disease (CKD) patient cohort.
Background: CVEs are common and significant complications amongst patients with CKD.
Method: A retrospective cohort study of 1,123 RBWH patients enrolled in the CKD.QLD registry from January 2011 to August 2017 with a minimum of 2 years follow up. Incident CVE included ischaemic heart disease (IHD), stroke and peripheral vascular disease (PVD), which were ascertained from discharge summaries. Delta eGFR(mL/min/1.73 m²/year, CKD-EPI) was calculated (difference between latest eGFR compared to eGFR at time of CVE incident), stratified by quartiles. Mortality was ascertained through electronic health records.
Results: There were 235 incident CVE amongst 222 patients. 144 patients experienced IHD, 51 patients stroke, 40 patients PVD and 13 patients had more than one event. The cumulative prevalence of CVE events increased with CKD stage; stage 1=4.5%, stage 2=12.1%, stage 3a=15.7%, stage 3b=24.9%, stage 4=25.4% but decreased in stage 5=9.6%. CVE were associated with significantly higher mortality in CKD patients (odd risk ratio 2.3; 95% CI 1.7-3.1; p<0.01). Multivariable analysis adjusting for age, gender, delta eGFR and history of PVD, stroke and IHD did not alter this significant association with mortality (p<0.05). CKD patients who experienced at least one CVE survived 2,167 (SE=61) days compared to 2,867 (SE=67) days who did not (Kaplan Meier p<0.01). Moreover, mortality was significantly (p<0.001) greater amongst patients in the fourth quartile of delta eGFR (49.4%) compared to first quartile of delta eGFR (21.3%).
Conclusion: Cardiovascular events and renal function deteriotion are associated with significant mortality in CKD patients.
Andrew Jeyaruban is currently a medical registrar with a keen interest in renal medicine. He graduated from James Cook University with Honours in 2014. Andrew then completed his residency at the Royal Brisbane and Women’s Hospital Brisbane, Australia. He is currently a basic physician trainee at the Liverpool Hospital, Sydney.