POST-STROKE HYPERGLYCEMIA AS A MARKER OF STROKE SEVERITY AND PROGNOSIS

Abstract

SUMMARY S troke is defined as brain dysfunction symptoms lasting more than 24 hours or imaging of an acute clinically relevant brain lesion in patient with rapidly vanishing symptoms lasting less than 24 hours but with infarction imaged by MRI have been reclassified as having stroke instead of transient ischemic attack. Hyperglycemia is encountered in 20% to 40 % of acute stroke patients,with or without a pre-morbid diagnosis of diabetes mellitus. Hyerglycemia is a risk factor for infarct expansion and poor outcome through the first 72 hours of hospitalization in both diabetics and non- diabetics. Stress hyperglycemia is defined as a transient plasma glucose level above 200 mg/dl and it is thought to be caused by the increased levels of cortisol, glucagon and epinephrine,theses hormones increase gluconeogenesis and decrease peripheral uptake of glucose to ensure substrate availability. This is also due to use of glucocorticoid therapy and continuous nutrition. Hyperglycemia is of interest as it is associated with poor outcomes from acute hospital admission for other conditions. Major and minor studies of stroke patients suggested that "stress hyperglycemia" (raised blood glucose levels without a previous diagnosis of diabetes) was associated with a poorer outcome. Stress hyperglycemia had the worst short-term outcome compared with diabetic group and control group (85.7% vs. 45% vs. 5%; respectively). It was found that Patients with hyperglycemia had higher incidence of intracerebral complications, namely hemorrhagic transformation (17.7%) and brain oedema (9.67%). A meta-analysis suggests that the relative risk of death in hyperglycemic non-diabetic stroke patients is increased by 3.3%, recent analysis of both prospective and case control studies have confirmed the importance of acute hyperglycemia as a predictor of outcome after stroke. Scales that measure neurological deficits or specific body functions can be used especially well for triage and to guide acute treatment decisions. The NIHSS,for example, is a valuable tool for initial assessments of patients with stroke in emergency departments,hospitals, or in the pre-hospital setting, and the confidence of the patient and family can be greatly enhanced by the ability to offer an accurate prognosis. A reliable prognosis allows better planning for supportive care, more accurate information to be given to relatives and resources to be allocated in a more efficient way.