Carotid intima‐media thickness and risk of mild cognitive impairment: A systematic review and meta‐analysis.

Mild cognitive impairment (MCI) is an early phase of cognitive decline signalling the beginning of severe neurological diseases. Carotid intima‐media thickness (cIMT) has shown some correlation with MCI development. This study was conducted to investigate the impact of elevated cIMT on the risk of MCI in adults. A literature search was conducted in PubMed, EMBASE, Cochrane Library, Scopus, Google Scholar and CINAHL databases till 30 July 2021, with keywords: ('Carotid Intima‐Media Thickness' OR 'cIMT' OR 'IMT' AND 'Cognitive Impairment' OR 'Cognition' OR 'Cognitive Decline' AND 'Mild Cognitive Impairment' OR 'MCI'). Pooled standardized mean difference (SMD)/odds ratio (OR) and 95% confidence interval (CI) were determined for factor–disease association using either fixed (when I2 <50%) or random effect (when I2 >50%) models. Eight studies involving 1,585 MCI cases and 6,700 normal subjects were included in our meta‐analysis which showed no significant association of increased cIMT with the risk of MCI [SMD 1.17, 95% CI −0.09 to 2.42]. However, sensitivity analysis revealed an outlier study significantly affecting the effect size. On omitting the outlier study, the re‐evaluated meta‐analysis revealed a significant association of cIMT with the risk of MCI [SMD 0.52, 95% CI 0.26 to 0.78]. This significant association was also observed during subgroup analysis in Caucasian population [SMD 0.65, 95% CI 0.13 to 1.18] but not in Asian population [SMD 0.39, 95% CI −0.01 to 0.79]. Elevated cIMT poses a potential risk for MCI. However, more population‐based studies are required to corroborate these findings. [ABSTRACT FROM AUTHOR]