Trends in incidence of ischaemic stroke in people with and without diabetes in Ireland 2005-2015

Aims: We aim to describe the epidemiology of ischaemic stroke and in-hospital mortality associated with stroke among men and women with and without diabetes from 2005 to 2015. Methods: Secondary data analysis of national hospital discharge data from the Hospital Inpatient Enquiry database. Stroke incidence and in-hospital mortality rates in people with and without diabetes were calculated. Poisson regression models were used to estimate the incidence rate ratio (IRR) and assess trends over time. Results: The age-adjusted incidence of stroke was twice as high in people with diabetes compared to those without diabetes (men IRR 2.0 [95% CI 1.95-2.06] and women IRR 2.2 [95% CI 2.12-2.27]). The incidence of ischaemic stroke decreased by an average 1.7% per year in men with diabetes and 3.3% per year in women with diabetes. In people without diabetes, the average annual reduction was smaller (0.2% per year in men and 1% per year in women). In-hospital mortality associated with admission with ischaemic stroke was approximately twice as high in those with diabetes compared to those without diabetes among men [IRR 1.81 (1.67-1.97)] and women [IRR 2 (95% CI 1.84-2.18)]. Conclusion: Despite decreases in incidence of ischaemic stroke and associated in-hospital mortality, there remains a twofold increased risk of ischaemic stroke and mortality in people with diabetes. Therefore, priority must be given to management of risk factors for ischaemic stroke in people with diabetes as well as continued development of targeted stroke prevention strategies.