The specific impact of uremic toxins upon cognitive domains: a review

ABSTRACT One of the mechanisms proposed for chronic kidney disease (CKD)-related cognitive impairment is the accumulation of uremic toxins due to the deterioration of the renal clearance function. Cognition can be categorized into five major domains according to its information processing functions: memory, attention, language, visual-spatial, and executive. We performed a review using the terms 'uric acid', 'indoxyl sulfate', 'p-cresyl sulfate', 'homocysteine', 'interleukins' and 'parathyroid hormone'. These are the compounds that were found to be strongly associated with cognitive impairment in CKD in the literature. The 26 selected articles point towards an association between higher levels of uric acid, homocysteine, and interleukin 6 with lower cognitive performance in executive, attentional, and memory domains. We also reviewed the hemodialysis effects on cognition. Hemodialysis seems to contribute to an amelioration of CKD-related encephalopathic dysfunction, although this improvement occurs more in some cognitive domains than in others.

摘要 目前针对慢性肾脏病（CKD）相关性认知损害提出的潜在机制之一，是肾脏清除功能衰退导致尿毒症毒素蓄积。根据信息处理功能的差异，认知可划分为五大核心认知域：记忆、注意、语言、视觉空间及执行功能域。本研究以“尿酸”“硫酸吲哚酚”“对甲酚硫酸酯”“同型半胱氨酸”“白细胞介素”“甲状旁腺激素”为检索词开展文献综述，上述化合物均为既往文献中证实与CKD患者认知损害显著相关的物质。纳入分析的26篇研究结果显示，尿酸、同型半胱氨酸及白细胞介素6水平升高，与执行、注意及记忆认知域的认知表现下降存在显著关联。本研究同时回顾了血液透析对认知功能的影响，结果提示血液透析可改善CKD相关性脑病功能障碍，但该改善效果在不同认知域中的表现存在差异。