Diabetes associated risk for mortality increases with time among first stroke survivors - Findings from the Israeli National Stroke Registry

Background: Diabetes is a major risk factor for ischemic stroke and may affect post-stroke survival. Previous large scale studies of long-term post-stroke survival are limited and most of them excluded older patients from the study population. Objectives: To compare the risk factors and sociodemographic characteristics between first ischemic stroke cases with and without diabetes and to assess the mortality risk associated with diabetes. Methods: Using population-based National Stroke Registry in Israel, all patients hospitalized for a first event of ischemic stroke between the years 2014-2018 were followed for all-cause mortality. Chi-square analysis was used to compare the differences in risk factors, sociodemographic profile and cumulative mortality between patients with and without diabetes. Cox proportional hazards models were used to estimate the hazard ratio for mortality in selected timeframes. Results: Among 41,639 patients with a first event of ischemic stroke, 44.5% were previously diagnosed with diabetes. Diabetic patients were more likely to be males, members of the Arab ethnic group, with lower socioeconomic status and a higher prevalence of cardiovascular comorbidities, anemia, leukocytosis and abnormal kidney function. Diabetes was associated with a higher mortality risk in the first year and long term, but not in the first month following stroke. Diabetes-associated mortality risk interacted with time and age, was higher in younger age and increased with time. Conclusions: Our findings suggest that diabetes is associated with a higher prevalence of comorbidities among patients with first ischemic stroke and with a higher risk for mortality in the mid and long term, which is more profound in younger age.