Intravenous insulin therapy in the maintenance of strict glycemic control in nondiabetic acute stroke patients with mild hyperglycemia

Abstract

Several reports indicate that mild hyperglycemia (plasma glucose level [PGL] ≥7.0 and ≤10.0 mmol/L [≥126 and ≤180 mg/dL]) is associated with poor prognosis in nondiabetic patients who sustain acute ischemic stroke (AIS). Insulin therapy to maintain PGL <7.0 mmol/L (<126 mg/dL) has been reported to be beneficial in critically ill patients, but the safety and efficacy of this approach in patients with AIS are not well established. In a prospective, open-label study, 50 consecutive nondiabetic patients with AIS admitted within 12 hours of ictus and with a PGL ≥7.0 and ≤10.0 mmol/L (≥126 and ≤180 mg/dL) were randomized to receive either a 24-hour intravenous (IV) insulin infusion (ISI) adjusted to maintain PGL within 4.5-7.0 mmol/L (81-126 mg/dL) (ISI group; n=26) or treatment with subcutaneous insulin if PGL was >10.0 mmol/L (>180 mg/dL) (control group [CG]; n=24). Patients' neurologic status was assessed based on National Institutes of Health Stroke Scale (NIHSS) score at admission, 24 hours and 30 days. The 2 groups did not differ in terms of risk factors for stroke. The mean PGL measured at admission was 8.25±0.9 mmol/L (149±16 mg/dL) in the ISI group and 8.1±0.8 mmol/L (146±14 mg/dL) in the CG (P=.8). After 24 hours, these values dropped to 4.9±0.5 mmol/L (88±9 mg/dL) and 5.5±0.45 mmol/L (99±8 mg/dL), respectively (P < .01). Two patients from the ISI group (8%) required IV glucose infusion for symptomatic hypoglycemia. There was no significant between-group difference in neurologic status at admission (median NIHSS score, 10±3 vs 10±2) and 24 hours later (8±2 vs 9±3). At 30 days, the median NIHSS score was 4±3 in the ISI group and 7±4 in the CG (P=.04). Our findings indicate that in nondiabetic AIS patients with mild hyperglycemia, IV insulin therapy aimed at maintaining strict glycemic control (PGL 4.5-7.0 mmol/L [81-126 mg/dL]) is relatively safe and may improve stroke outcome.