Factors influencing early neurological improvement after mechanical thrombectomy among patients with acute basilar artery occlusion: a single center prospective observational cohort study.

The predictive value of and the influencing factors associated with early neurological improvement (ENI) among patients with acute basilar artery occlusion (BAO) have not been well studied. The present study aimed to evaluate whether ENI predicted a better functional outcome and to identify the influencing factors of ENI. We performed a prospective observational analysis among 187 patients with acute BAO who underwent endovascular treatment (EVT) in Beijing Tiantan Hospital from January 2012 to July 2018. ENI was defined as having a drop on the National Institutes of Health Stroke Scale (NIHSS) by 8 or more scores or having a NIHSS of 0-1 within 24 h after EVT. A multivariate logistic regression model with backward selection was used to identify the influencing factors associated with ENI. ENI had a sensitivity of 0.69 and a specificity of 0.68 to predict a favorable outcome at 90 days after EVT. In addition, patients with ENIs had lower modified Rankin Scale score (mRS) (median: 2.0 vs. 5.0, p < 0.001) and were more likely to survive (95.2% vs. 72.0%, p < 0.001) and achieve functional independence (74.2% vs. 36.8%, p < 0.001). NIHSS before EVT, complete recanalization, white blood cell counts and general anesthetics were significant factors associated with ENI. A one-unit higher NIHSS and complete recanalization were associated with 1.04 (95% CI 1.01-1.08) and 2.71 (95% CI 1.14-6.45) times higher odds of achieving ENI, respectively. In conclusion, in patients with acute BAO, ENI within 24 hours after EVT can predict favorable outcomes at 90 day. Patients with higher NIHSS, lower white blood cell counts before surgery, without general anesthetics and patients with complete recanalization were more likely to achieve ENIs.