Impact of Serum Cystatin C Level on Long-Term Cognitive Impairment After Acute Ischemic Stroke and Transient Ischemic Attack

Lijun Zuo,1 Yanhong Dong,2 Yuesong Pan,3 Hongyi Yan,3 Xia Meng,3 Hao Li,3 Xingquan Zhao,1 Yilong Wang,1 Yongjun Wang,1 Xiaoling Liao1 1Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, People’s Republic of China; 2Alice Lee Centre for Nursing Studies, Yong Loo Lin School of Medicine, National University of Singapore, Clinical Research Centre, Singapore, 117597, Singapore; 3National Clinical Research Center for Neurological Diseases, Beijing Tiantan Hospital, Capital Medical University, Beijing, People’s Republic of ChinaCorrespondence: Xiaoling Liao, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, No. 119, South Fourth Ring West Road, Fengtai District, Beijing, 100070, People’s Republic of China, Tel +86-010-59978350, Fax +86-010-59973383, Email liao828@sina.comObjective: Cognitive impairment after stroke/transient ischemic attack (TIA) has a high prevalence. Cystatin C (CysC) has been found as a novel biomarker of neurodegenerative diseases, such as dementia and Alzheimer’s disease. We aimed to explore the possible correlations of serum CysC level with cognitive impairment in patients who had mild ischemic stroke and TIA after 1 year.Methods: We measured serum CysC level in 1025 participants with a minor ischemic stroke/TIA from enrolled from the Impairment of Cognition and Sleep (ICONS) study of the China National Stroke Registry-3 (CNSR-3). They were divided into four groups according to quartiles of baseline CysC levels. Patients’ cognitive functions were assessed by Montreal Cognitive Assessment (MoCA)-Beijing at day 14 and at 1 year. Multiple logistic regression models were performed to evaluate the relationship between CysC and post-stroke cognitive impairment (PSCI) at 1-year follow-up.Results: Cognitive impairment was defined as MoCA-Beijing ≤ 22. Most patients were in 60s (61.52± 10.97 years old) with a median (interquartile range) National Institute of Health Stroke Scale(NIHSS) score of 3.00 (4.00) and greater than primary school level of education, and 743 participants (72.49%) were male. Among the 1025 participants, 331 participants (32.29%) patients suffered PSCI at 1-year follow-up. A U-shaped association was observed between CysC and 1-year PSCI [quartile (Q)1 vs Q3: adjusted odds ratio (aOR) 2.69, 95% CI 1.67– 4.34, p < 0.0001; Q2 vs Q3: aOR 1.63, 95% CI 1.03– 2.57, p = 0.0354; Q4 vs Q3: aOR 1.83, 95% CI 1.16– 2.87, p = 0.009]. Moreover, the U-shaped trends were also found between CysC level and the subscores of attention, recall, abstraction and language in MoCA.Conclusion: CysC showed a U-shaped correlation with 1-year overall cognitive function. It is probable that measurement of the serum CysC level would aid in the early diagnosis of PSCI.Keywords: mild stroke, post stroke cognitive impairment, cystatin C