Effect of hyperglycemia on stroke outcome is not homogeneous to all patients treated with mechanical thrombectomy

Objectives: Admission hyperglycemia is a penumbra-modifying factor that is associated with poor functional outcome in acute ischemic stroke (AIS) patients treated with intravenous rt-PA and/or mechanical thrombectomy (MT). Insulin therapy has failed to demonstrate a clinical benefit and the question of the patient selection remains under debate. We assessed the relationship between admission glycemia (AG) and functional outcome in AIS patients treated by MT according to both penumbra characteristics and reperfusion status. Patients and methods: We performed a retrospective analysis of a multi-center registry of consecutive AIS (NIHSS >= 10) due to middle cerebral artery occlusion treated by MT ( +/- tissue Plasminogen Activator (WA)). To evaluate the association between AG and the 3-month functional outcome (modified Rankin Scale (mRS) <= 2), univariable and multivariable analyses were used. Subgroup analyses were performed according to both clinical-ASPECTS Mismatch (CAM2) and the complete recanalization (CR) status defined by a mTICI scale (modified Thrombolysis in Cerebral Infarction) 2b/3. Results: 216 AIS patients were included (Median Age: 68.43[58.12-77.95], median NIHSS: 18[15-21]). 104/216 (48.15%) patients had mRS <= 2 at 3 months. AG was an independent predictor of functional outcome (/1 g/L OR: 0.10[0.03-0.37]) after adjusting for potential cofounders. Among subgroups formed by combining CAM2 and CR, AG was found to be predictor of functional outcome only in CAM2(+)/CR+ and specifically when recanalization was early. Conclusion: This study highlights the fact that the relationship between AG and prognosis is not homogeneous for all patients and indicates that AG has a deleterious effect on the ischemic penumbra, thus explaining its statistical association with functional outcome. Stroke neuroprotection by targeting hyperglycemia should be considered in acute stroke patients with mismatch and early complete recanalization. More prospective randomized trials are needed to generalize the conclusions.