Relationship between hyperglycemia and symptomatic vasospasm after subarachnoid hemorrhage

Objective: To determine the relationship between blood glucose levels (mg/dL) and occurrence of symptomatic vasospasm (VSP) and clinical outcomes after aneurysmal subarachnoid hemorrhage. Design: Retrospective observational study of 352 patients with subarachnoid hemorrhage admitted within 48 hirs of ictus between January 1995 and June 2002. Setting: Neurointensive care unit. Patients: Adult patients admitted after subarachnoid hemorrhage. Interventions: None. Measurements and Main Results. Variables included age; Hunt-Hess classification score; Fisher group; insulin use; infectious disease status; history of diabetes mellitus; and blood glucose values. Poor clinical outcome was defined by a modified Rankin score >= 3, and hyperglycemia was defined by a blood glucose level > 140 mg/dL. Mean daily blood glucose values were assessed from admission to development of VSP or day 14. Mean admission blood glucose value, mean inpatient blood glucose value, insulin use, infectious disease status, Hunt-Hess classification score, Fisher group, and history of diabetes mellitus were entered in a Cox proportional hazards model. VSP occurred in 103 (29.2%) of 352 patients. Mean admission blood glucose values (176.6 +/- 40.3 mg/dL vs. 162.3 +/- 47.8 mg/dL; p = .01) and mean inpatient blood glucose values (166.2 +/- 24.7 mg/dL vs. 155.8 +/- 29.7 mg/dL; p = .001) were significantly higher in patients with VSP. Mean inpatient blood glucose value (relative risk, 1.01; 95% confidence interval, 1.0-1.03; p = .04), Hunt-Hess classification score >= 3 (relative risk, 2.23; 95% confidence interval, 1.21-3.99; p = .02), and Fisher group score of 3 (relative risk, 1.28; 95% confidence interval, 1.15-3.1; p = .05) increased the risk for VSP. Hyperglycemia was associated with longer length of stay in the neurointensive care unit (14.5 +/- 7.1 days vs. 11.6 +/- 5.4 days; p < .001) and poor outcome at discharge (modified Rankin score >= 3: 58.9% vs. 18.8%; p < .001). Conclusions. Mean inpatient blood glucose value is associated with the development of VSP and may represent a target for therapy to prevent VSP and improve clinical outcomes.