Low Haemoglobin Levels At Admission Are Independently Associated With Cognitive Impairment After Ischemic Stroke

Background and Objectives:Low hemoglobin(Hb)or anaemia is associated with cognitive impairment and Alzheimer' Disease(AD),but data on the association between hemoglobin and post-stroke cognitive function are limited.We aimed to investigate the relation between hemoglobin concentration at admission and cognitive performance in patients after acute ischemic stroke,using a multicenter database.Methods:920 patients with acute ischemic stroke were admitted consecutively from seven Chinese medical centers in Zhejiang Province between November 2013 and December 2015.Hb and hematocrit(Hct)levels were measured on blood samples.Cognition was accessed by the Mini-Mental State Examination at 14 days.A subgroup of 165 patients from one center was followed up for 3 months.Post-stroke Cognitive impairment(PSCI)was considered present when MMSE<26.Univariate and multivariate logistic regressions were used to evaluate the impact of Hb or Hct on PSCI.Results:After adjusting for multiple covariables,the lowest tertile of Hb(68-130g/L)was independently associated with increased risk of PSCI(OR,1.79;95%confidence interval[CI],1.15-2.81)at 14 days as compared with the highest tertile(145-190g/L).Similar association was found across Hct tertiles.After three-month followed-up,patients both in the lowest and middle Hb tertiles carried a significant higher risk of PSCI(OR,1.79;95%confidence interva[CI]1,1.15-2.81).This trend in risk of PSCI was still observable when adjusted for age,sex and education years.Conclusion:Both low Hb and Hct independently correlated with early PSCI.Findings suggest that further study of anemia as a risk factor for PSCI and a target for intervention for cognitive health is warranted.