Nair P, Misra S, Nath M, et al. - Given that cystatin C (Cys C) has been determined to be a novel biomarker of neurodegenerative diseases like dementia and Alzheimer disease, researchers conducted this systematic review and meta-analysis to explore the connection between Cys C and risk of mild cognitive impairment (MCI). Comprehensive searches were conducted in PubMed, EMBASE, Cochrane Library, Trip databases, Worldwide Science, and Google Scholar from January 1, 1950, to April 30, 2020. The sample consisted of 2,433 MCI patients and 1,034 controls. Increased levels of Cys C is strongly linked with risk of MCI vs control subjects. A significant correlation between high level of Cys C and the risk of MCI was seen in the Asian population, but not in the Caucasian population, in subgroup analysis based on ethnicity. Findings suggested that Cys C is correlated with MCI and could predict the risk of cognitive impairment.