Acute hyperglycemia state is associated with lower tPA-induced recanalization rates in stroke patients

Background and Purpose - Hyperglycemia (HG) has a deleterious effect in stroke patients by accelerating ischemic brain damage; moreover, its antifibrinolytic effect may also influence reperfusion. We aimed to study the effect of acute/chronic HG on tissue-type plasminogen activator (tPA)- induced recanalization. Methods - We studied 139 consecutive stroke patients with documented intracranial artery occlusion treated with intravenous tissue-type plasminogen activator (tPA). Admission glucose levels were recorded (in mg/dL). The existence of previous chronic HG was determined by plasma levels of glycosylated hemoglobin (HbA1c, %) and fructosamine (in mu mol/L). Transcranial Doppler monitoring assessed complete recanalization 2 hours after tPA bolus. National Institutes of Health Stroke Scale (NIHSS) scores were obtained at baseline and 48 hours. Results - On admission, the median NIHSS score was 18 and mean glucose value was 140 +/- 63 mg/dL. At 2 hours, 32% of patients(n = 44) achieved complete recanalization. Patients who recanalized showed lower admission glucose levels (127 vs 146 mg/dL; P = 0.039) but no differences in HbA1c (6.3% vs 6.3%; P = 0.896) or fructosamine (292 vs 293 mu mol/L; P = 0.957) were observed. Other variables associated with recanalization were initial distal middle cerebral artery occlusion (P = 0.011) and platelet count (P = 0.015). Patients with an admission glucose level >158 mg/dL had lower recanalization rates (16% vs 36.1%; P = 0.035) and a higher NIHSS score at 48 hours (7 vs 14.5; P = 0.04). After adjustment for stroke etiology, age, and risk factors, the only independent predictors on admission of no recanalization were glucose value >158 mg/dL (odds ratio [OR], 7.3; 95% confidence interval [CI], 1.3 to 42.3; P = 0.027), proximal middle cerebral artery occlusion (OR, 2.6; 95% CI, 1.1 to 6.5; P = 0.034), and platelet count <219 000/mL (OR, 2.6; 95% CI, 1.1 to 6.1; P = 0.029). Conclusions - In tPA-treated patients, the acute but not chronic HG state may hamper the fibrinolytic process, delaying reperfusion of the ischemic penumbra. Early measures to reduce HG may favor early recanalization.