Leukoaraiosis Mediates the Association of Total White Blood Cell Count With Post-Stroke Cognitive Impairment

Wanying Shan; Liang Xu; Yuan Xu; Zhuoyin Qiu; Jie Feng; Jie Zhao; Jingwen Wang

doi:10.3389/fneur.2021.793435

Leukoaraiosis Mediates the Association of Total White Blood Cell Count With Post-Stroke Cognitive Impairment

Front Neurol. 2022 Feb 3:12:793435. doi: 10.3389/fneur.2021.793435. eCollection 2021.

Authors

Wanying Shan¹, Liang Xu², Yuan Xu¹, Zhuoyin Qiu¹, Jie Feng¹, Jie Zhao³, Jingwen Wang¹

Affiliations

¹ Department of Neurology, Suzhou Ninth People's Hospital, Soochow University, Suzhou, China.
² Department of Anesthesiology, The First Affiliated Hospital of Soochow University, Suzhou, China.
³ Department of Gerontology, Suzhou Ninth People's Hospital, Soochow University, Suzhou, China.

Abstract

Background and purpose: The inflammatory response could play a key role in cognitive impairment. However, there has been limited research into the association between total white blood cell (WBC) count and post-stroke cognitive impairment (PSCI), and the significance of leukoaraiosis (LA) in this relationship is unknown. We aimed to examine the total WBC count in relation to PSCI and whether this association was mediated by LA.

Methods: Consecutive patients with first-ever ischemic stroke were prospectively enrolled from October 2020 to June 2021. The total WBC count was measured after admission. Cognitive function evaluations were performed at the 3-month follow-up using Mini-mental State Examination (MMSE). We defined the PSCI as an MMSE score <27.

Results: A total of 276 patients (mean age, 66.5 years; 54.7% male) were included in this analysis. Among them, 137 (49.6%) patients experienced PSCI. After adjustment for potential confounders, higher total WBC count was significantly correlated with an increased risk of LA [per 1-SD increase, odds ratio (OR), 1.39; 95% CI 1.06-1.82; p = 0.017] and PSCI (per 1-SD increase, OR, 1.51; 95% CI 1.12-2.04; p = 0.006). Furthermore, mediation analysis demonstrated that the association between total WBC count and PSCI was partly mediated by LA (the regression coefficient was changed by 9.7% for PSCI, and 12.4% for PSCI severity, respectively).

Conclusion: Increased total WBC count is a risk factor for PSCI. The presence of LA was partially responsible for the PSCI in patients who had a higher total WBC count.

Keywords: PSCI; leukoaraiosis; mediation analysis; stroke; white blood cell.