Elevated blood glucose is associated with aggravated brain edema in acute stroke

Clinical outcome after endovascular thrombectomy in patients with acute ischemic stroke still varies significantly. Higher blood glucose levels (BGL) have been associated with worse clinical outcome, but the pathophysiological causes are not yet understood. We hypothesized that higher levels of BGL are associated with more pronounced ischemic brain edema and worse clinical outcome mediated by cerebral collateral circulation.

178 acute ischemic stroke patients who underwent mechanical thrombectomy were included. Early ischemic brain edema was determined using quantitative lesion water uptake on initial computed tomography (CT) and collateral status was assessed with an established 5-point scoring system in CT-angiography. Good clinical outcome was defined as functional independence (modified Rankin Scale [mRS] score 0-2). Multivariable logistic regression analysis was performed to predict functional independence and linear regression analyses to investigate the impact of BGL and collateral status on water uptake.

The mean BGL at admission was significantly lower in patients with good outcome at 90 days (116.5 versus 138.5 mg/dl; p < 0.001) and early water uptake was lower (6.3% versus 9.6%; p < 0.001). The likelihood for good outcome declined with increasing BGL (odds ratio [OR] per 100 mg/dl BGL increase: 0.15; 95% CI 0.02-0.86; p = 0.039). Worse collaterals (1% water uptake per point, 95% CI 0.4-1.7%) and higher BGL (0.6% per 10 mg/dl BGL, 95% CI 0.3-0.8%) were significantly associated with increased water uptake.

Elevated admission BGL were associated with increased early brain edema and poor clinical outcome mediated by collateral status. Patients with higher BGL might be targeted by adjuvant anti-edematous treatment.