P MASSON1, NL DE LA MATA2, RA SALMAN3, P KELLY2, AC WEBSTER2,4,5
1Department of Renal Medicine, Royal Infirmary of Edinburgh, Edinburgh, Scotland, UK; 2Sydney School of Public Health, Sydney Medical School, University of Sydney, Sydney, NSW, Australia; 3Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, Scotland, UK; 4Centre for Renal and Transplant Research, Westmead Hospital, Westmead, NSW, Australia; 5Centre for Kidney Research, The Children’s Hospital at Westmead, Sydney, NSW, Australia.
Aim: To compare death rates from stroke and stroke subtypes (ischaemic, haemorrhagic and all-cause stroke) between people with end stage kidney disease (ESKD) and the general population in Australia and New Zealand.
Background: Stroke incidence is higher in ESKD, but any mortality differences remain unclear.
Methods: We included all incident ESKD patients in Australia, 1980-2013 and New Zealand, 1988-2012, obtained from ANZDATA. Using data linkage, we ascertained the cause of death from the respective national death registries. Crude mortality rates were estimated for all-cause and cause-specific stroke deaths in the ESKD population. We used indirect standardization to estimate standardized mortality ratios (SMR) by age, gender and calendar year, using the general population as a reference.
Results: We included 58,241 ESKD patients. There were 873 stroke deaths, including 108 ischaemic strokes, 259 intracerebral haemorrhages, 90 intracranial haemorrhages and 416 unspecified or other strokes, over 259,973 person-years (pys). The crude all-cause stroke mortality rate was higher in females (398.0 per 100,000 pys; 95% CI: 362.3-437.3) than males (290.9 per 100,000; 95% CI: 265.0-319.5) and increased with age. The all-cause stroke SMRs were greater for those of younger age and of female gender, where ESKD patients aged 30-49 years had more than 40 times the number of stroke deaths than expected in the general population (Females: SMR 80.2, 95% CI: 59.5-108.1; Males: SMR 41.7, 95% CI: 31.4-55.3). The SMRs for ischaemic and intracerebral haemorrhages followed a similar trend.
Conclusions: Australian and New Zealand stroke mortality rates are greater in the ESKD population than the general population. In particular, the number of stroke deaths were excessively high in ESKD patients aged 30-49 years and of female gender.