Recurrent ischaemic stroke hospitalisations: a retrospective cohort study using Western Australia linked patient records.

A retrospective cohort study was undertaken to determine factors that affect the frequency of recurrent ischaemic stroke hospitalisations. Linked hospitalisation records of all Western Australian patients admitted for ischaemic stroke for the first time during July-December 1995 were retrieved until December 2000 to derive the number of readmissions for recurrent strokes, patient medical conditions and co-morbidities at the index episode. A negative binomial regression model adjusting for inter-hospital variations was used to determine the prognostic factors influencing recurrent stroke hospitalisations. Of the 678 patients in the cohort, 124 (18.3%) experienced repeated episodes of ischaemic stroke. Rural residence and carotid endarterectomy procedure were positively associated with the recurrence frequency, the adjusted incidence rate ratio being 1.66 (95% CI: 1.17-2.36) and 3.96 (95% CI: 2.30-6.82), respectively. Rural patients contributed to 18% of the patients in the cohort yet they accounted for 27% of those sustaining repeated episodes of stroke. Readmissions were also related to the presence of diabetes at the index episode. The effect of diabetes, with adjusted incidence rate ratio 1.35 (95% CI: 1.01-1.79), was only evident after accounting for within hospital correlations. These findings have implications on hospital resource planning and secondary preventive strategies to reduce the burden of stroke.