Effect of type 2 diabetes on mortality risk associated with end-stage kidney disease

Aims/hypothesis: Patients with end-stage kidney disease (ESKD) and patients with diabetes mellitus experience higher mortality rates than the general population. Whether ESKD imparts the same excess in mortality risk for those with diabetes as it does for those without diabetes is unknown. Methods: Included in the study were all white patients aged ≥25 years with incident ESKD and type 2 diabetes (n=4,141) or with incident ESKD but without diabetes (n=13,289) in Australia from 1991 to 2005, and all the individuals aged ≥25 years without ESKD and with type 2 diabetes (n=909) or without ESKD without diabetes (n=10,302) enrolled in the AusDiab Study-a nationwide Australian representative cohort-from 1999 to 2005. Excess mortality was analysed in patients with ESKD by diabetes status, using age-, sex- and diabetes-status- specific standardised mortality ratios (SMRs) in the first 8 years after first renal replacement therapy among ANZDATA patients relative to AusDiab participants. Results: The SMRs in patients with ESKD were, in non-diabetic patients and in those with type 2 diabetes, respectively: 14.2 (95% CI 13.9-14.6) and 10.8 (95% CI 10.4-11.2) (p<0.01); in people aged <60 years, 28.7 (95% CI 27.2-30.4) and 18.6 (95% CI 17.1-20.4) (p<0.01); in people aged ≥60 years, 12.5 (95% CI 12.1-12.9) vs 9.7 (95% CI 9.3-10.1) (p<0.01); in men, 11.0 (95% CI 10.7-11.4) vs 8.9 (95% CI 8.4-9.3) (p<0.01); and in women, 23.4 (95% CI 22.5-24.3) vs 16.2 (95% CI 15.2-17.3) (p<0.01). Conclusions/interpretation: ESKD was associated with a greater relative increase in mortality in the non-diabetic study populations than in the type 2 diabetes population. Excess mortality was greater among younger people and women.