Hyperglycemia, Large Ischemic Core Volumes Seen in Acute Ischemic Stroke

In patients with acute ischemic stroke who undergo endovascular treatment (EVT), hyperglycemia on admission is associated with larger ischemic core volumes and a larger core-penumbra ratio, according study findings published in the Journal of Neurological Sciences.

It is well known that hyperglycemia is highly prevalent among those with acute ischemic stroke, and is associated with an elevated risk for symptomatic intracranial hemorrhage, larger infarct size, and unfavorable outcomes. It remains unclear whether hyperglycemia on hospitalization is associated with the size of the infarct core or the penumbra among these individuals.

For the study, researchers evaluated the link between hyperglycemia and computed tomographic perfusion (CTP) derived parameters among individuals who underwent EVT for acute ischemic stroke.

The researchers collected data from the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands (MR CLEAN). All of the individuals who had enrolled in MR CLEAN, among whom CTP data and admission serum levels were available, were able to participate in this study. MR CLEAN was a randomized controlled trial that evaluated the effect of EVT vs standard care in patients with acute ischemic stroke.

In this study, hyperglycemia was defined as an admission serum glucose of >7.8 mmol/L. The hypoperfused area represents the mean transient time 45% higher than that of the contralateral hemisphere. The core is the area with a cerebral blood volume of <2 mL/100 g. The penumbra represents the area with a cerebral blood volume of >2 mL/100 g.

The primary outcome measures of the study included ischemic core and penumbra volumes, expressed in mL, as well as the core-penumbra ratio — that is, the ischemic core divided by the total volume of hypoperfused tissue (core plus penumbra) multiplied by 100. Secondary outcome measures included functional outcome, as evaluated by modified Rankin Scale (mRS) score at 90 days. A favorable outcome was defined as an mRS score of 0 to 2.

A total of 173 patients were enrolled in the study. The median glucose level among the participants on admission was 6.5 mmol/L (range, 5.8-7.5 mmol/L). Overall, 20% (35 of 173) of the participants were hyperglycemic. The median core volume reported was 33.3 mL (range, 13.6-62.4 mL). The median penumbra volume was 80.2 mL (range, 36.3-123.5 mL); the median core-penumbra ratio was 28.5% (range, 18.6%-45.8%).

Among those participants with hyperglycemia when hospitalized, larger core volumes and larger core-penumbra ratios were reported compared with normoglycemic individuals, with a regression coefficient of 15.1 (95% CI, 1.8-28.3) and 11.5 (95% CI, 3.4-19.7, respectively).

Study limitations included the fact that since MR CLEAN was a multicenter trial, the imaging data obtained used different CT scans and protocols. Data from only a small subgroup of the MR CLEAN population were available, because CTP is not part of a standard workup for patients with acute ischemic stroke and some poorly accessible CTPs were included.

The researchers concluded that “Further studies are needed to assess if lowering glucose levels in patients with acute ischemic stroke and hyperglycemia who underwent endovascular treatment results in smaller core volumes on CTP and possibly also into better functional outcome.”

Disclosure: Some of the study authors have declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of the authors’ disclosures. 

Reference

Kersten CJBA, Zandbergen AAM, et al; MR CLEAN investigators. Association of hyperglycemia and computed tomographic perfusion deficits in patients who underwent endovascular treatment for acute ischemic stroke caused by a proximal intracranial occlusion: a subgroup analysis of a randomized phase 3 trial (MR CLEAN). J Neurol Sci. Published online June 30, 2022. doi:10.1016/j.jns.2022.120333