OBJECTIVE -To determine the prevalence of disturbances in glucose metabolism in patients with acute stroke.RESEARCH DESIGN AND METHODS -Consecutively admitted acute stroke patients (n ϭ 286) were screened for glucose tolerance according to the standardized World Health Organization protocol in the 1st and 2nd week after the stroke event. In addition, we repeatedly measured fasting capillary blood glucose during the first 10 days.RESULTS -Measurements were not performed or cancelled if patients were not fully conscious or had severe dysphagia or early complications that made transfers to other hospitals necessary (n ϭ 48). Of the remaining 238 patients, 20.2% had previously known diabetes; 16.4% were classified as having newly diagnosed diabetes, 23.1% as having impaired glucose tolerance (IGT), and 0.8% as having impaired fasting glucose; and only 19.7% showed normal glucose levels. Another 47 patients (19.7%) had hyperglycemic values only in the 1st week (transient hyperglycemia) or could not be fully classified due to missing data in the oral glucose tolerance test. Patients with diabetes compared with nondiabetic subjects had more severe strokes (National Institutes of Health Stroke Scale [NIHSS] on admission: 7.2 Ϯ 6.6 vs. 4.6 Ϯ 3.1, 4.2 Ϯ 4.4, and 3.7 Ϯ 3.6 for IGT, transient hyperglycemia, and normoglycemia, respectively; P Ͻ 0.001), a worse outcome (modified Rankin scale 0 -1 at discharge: 40.2 vs. 54.4, 63.8, and 72.3% for IGT, transient hyperglycemia, and normoglycemia, respectively; P Ͻ 0.001), and a higher rate of infectious complications (35.6 vs. 12.3, 21.2, and 4.2% for IGT, transient hyperglycemia, and normoglycemia, respectively; P Ͻ 0.001). In the multivariate analysis, NIHSS on admission, female sex, and the occurrence of urinary tract infection were independently associated with newly diagnosed diabetes.CONCLUSIONS -The majority of acute stroke patients have disorders of glucose metabolism, and in most cases this fact has been unrecognized. Diabetes worsens the outcome of acute stroke. Therefore, in the post-acute phase, an oral glucose tolerance test should be recommended in all stroke patients with no prior history of diabetes. Diabetes Care 29:792-797, 2006T he prevalence of disturbances of glucose metabolism in acute stroke has hitherto not been properly investigated in a Western population. By a Chinese study (1), diabetes and impaired glucose tolerance (IGT) were diagnosed by performing an oral glucose tolerance test (OGTT) within 3-6 months after stroke in 33.5 and 21%, respectively, of patients. Of individuals with diabetes, 40% were previously undiagnosed. In the cohort of the Glucose Insulin in Ischemic Stroke Trial (GIST) (2) patients without previously known diabetes, 21% had diabetes, 37% had IGT, and 42% had normal glucose values 3 months after stroke. However, only 44% of randomized patients underwent the OGTT protocol in this study. In a study of patients with acute coronary syndromes (3), two-thirds had disturbances of glucose metabolism. In a recent study (4), more than half ...