Cognitive performance in patients with Mild Cognitive Impairment and Alzheimer's disease with white matter hyperintensities: An exploratory analysis

ABSTRACT. Background: White matter hyperintensities (WMH) are commonly associated with vascular dementia and poor executive functioning. Notwithstanding, recent findings have associated WMH with Alzheimer's disease as well as other cognitive functions, but there is no consensus. Objective: This study aimed to verify the relationship between WMH and cognitive performance in Mild Cognitive Impairment (MCI) and Alzheimer's disease (AD) patients. The study also sought to identify cognitive and demographic/cultural factors that might explain variability of WMH. Methods: The sample was composed of 40 participants (18 MCI and 22 AD patients) aged ≥ 65 years. Spearman's correlation was performed among cognitive performance (memory, language, visuospatial ability, and executive function) and WMH evaluated by the Fazekas and ARWMC scales. Two stepwise linear regressions were carried out, one with cognitive and the other with demographic/cultural variables as predictors. Results: Only naming showed significant correlation with ARWMC. Fazekas score exhibited significant correlation with all cognitive domains evaluated. Fazekas score was better predicted by episodic visual memory and age. Conclusion: This study found that the most relevant cognitive profile in MCI and AD patients with WMH was related to episodic memory. And, without taking clinical aspects into consideration, age was the best predictor of WMH.

摘要。背景：脑白质高信号（White matter hyperintensities, WMH）常与血管性痴呆及执行功能受损相关。尽管如此，近期研究发现脑白质高信号亦与阿尔茨海默病（Alzheimer's disease, AD）及其他认知功能存在关联，但目前尚未形成统一共识。目的：本研究旨在验证轻度认知障碍（Mild Cognitive Impairment, MCI）与阿尔茨海默病患者的脑白质高信号与认知表现之间的关联，并探究可能解释脑白质高信号异质性的认知、人口学及文化相关因素。方法：本研究纳入40名年龄≥65岁的受试者，其中轻度认知障碍患者18例，阿尔茨海默病患者22例。采用Fazekas量表与ARWMC量表评估脑白质高信号，并对认知表现（记忆、语言、视空间能力及执行功能）与脑白质高信号进行斯皮尔曼相关性分析。随后开展两步逐步线性回归分析，分别以认知变量与人口学/文化变量作为预测因子。结果：仅命名能力与ARWMC量表评分存在显著相关性；Fazekas量表评分与所有评估的认知域均存在显著相关性。情景视觉记忆与年龄可更好地预测Fazekas量表评分。结论：本研究发现，在合并脑白质高信号的轻度认知障碍与阿尔茨海默病患者中，最具相关性的认知特征与情景记忆相关；而未纳入临床相关因素时，年龄是预测脑白质高信号的最佳因子。