Optimal target range for blood glucose in hyperglycaemic patients in a neurocritical care unit.

Background: Hyperglycaemia is common among patients with critical neurological injury, even if they have no history of diabetes. The optimal target range for normalizing their blood glucose is unknown.

Methods: Retrospective data were extracted from 890 hyperglycaemic individuals (glucose > 200 mg/dL) admitted to neuroscience critical care unit (NCCU) and these patients were divided into two groups: intensive glucose control group with target glucose of < 140 mg/dL achieved and moderate control with glucose levels 140-180 mg/dL. The groups were also stratified according to the hyperglycaemia type (pre-existing diabetes or stress-related). We defined the primary endpoint as death from any cause during NCCU admission.

Results: In NCCU, tighter control of blood glucose at ≤ 140 mg/dL was associated with increased, mortality of individuals with pre-existing diabetes compared with moderate control [29 of 310 patients (9.4%) vs 15 of 304 patients (4.9%), p = 0.034]. Patient age [adjusted odds ratio (OR) = 1.12; 95% confidence interval (CI) = 1.05-1.19; p < 0.001], level of glycated haemoglobin (adjusted OR = 1.24; 95% CI = 1.04-1.48; p = 0.017) and hypoglycaemia (adjusted OR = 10.3; 95% CI = 2.92-36.6; p < 0.001) were positively associated with higher mortality. Death rate was lower among stress-related hyperglycaemic patients with tighter glucose controlled at ≤ 140 mg/dL [6 of 140 patients (4.3%) vs 15 of 136 patients (11.0%), p = 0.035].

Conclusion: A differential association is evident between glucose levels and mortality in diabetes and stress-related hyperglycaemia patients. However, given the observational nature of our work, no clinical recommendations can be given and prospective studies are required to further investigate these findings.