Impact of Diabetes Mellitus (DM) on the Health-Care Utilization and Clinical Outcomes of Patients with Stroke in Singapore

Abstract

This study aims to assess the impact of diabetes mellitus (DM) on the health-care utilization and clinical outcomes of patients with acute stroke. This is a retrospective cohort study. All patients who were admitted for the first time to one of the three public hospitals in the National Healthcare Group in Singapore from January 2005 to June 2007 with a primary diagnosis of acute stroke were included and were followed up for 1 year after the index hospitalization. The study population was divided into two groups: with DM and without DM. Both univariate and multivariate analyses were applied to compare the hospital length of stay (LOS), hospitalization costs, mortality, as well as the 1-year hospital readmissions between the DM and non-DM groups. There were 9766 study patients, and 38.5% of them had DM. DM patients with ischemic stroke (IS) and transient ischemic attack (TIA) stayed 1-day and 0.6-day longer, and incurred 10% and 26% higher hospital cost during index admission, respectively, compared with their counterparts in the non-DM group. They also had more hospital readmission within 1 year. The mortality rate in IS patients with diabetes was 24% higher. After risk adjustment, subarachnoid hemorrhage patients with diabetes had more hospitalizations. Intracerebral hemorrhage (ICH) and IS patients in the DM group had all worse outcomes but the 1-year stroke recurrence; TIA patients with DM incurred longer LOS and hospital costs. DM predicts worse clinical outcomes and higher health-care expenditures in the 1-year poststroke especially for the IS, ICH, and TIA stroke subtypes.