Cognitive profile of chronic kidney disease and hemodialysis patients without dementia

Abstract

Background/aims: The high risk and prevalence of dementia among patients with chronic kidney disease (CKD) and in those receiving hemodialysis (HD) may be preceded by mild cognitive impairment (MCI). We aimed to assess cognitive function in CKD and HD patients with no history of stroke or dementia, in order to identify and characterize early cognitive deficits.

Methods: 24 CKD and 27 HD male outpatients without history of cerebrovascular or neurodegenerative disease underwent comprehensive neuropsychological testing in an observational cross-sectional study. Test results were used to categorize patients into MCI subtypes.

Results: All subjects scored ≥28 on the Mini-Mental State Examination. The prevalence of executive function was at least 25% in both groups and memory impairment occurred in 13% of the HD patients and 15% of those with CKD. MCI occurred in 76% of the group and HD patients showed a higher prevalence of MCI compared to CKD patients (89 vs. 63%) with a preponderance (>70%) of cases across both groups classified as non-amnestic MCI.

Conclusion: Predialysis CKD and HD patients have a high prevalence of MCI despite normal global cognitive function. MCI was more prevalent among the HD patients and deficits more frequently resulted in non-amnestic MCI.

Fig. 1

Mild cognitive impairment by subtype. Diagnostic criteria: Amnestic MCI single domain was defined as ≥1.5 SD below the norm on delayed recall composite score. Amnestic MCI multiple domain was defined as ≥1.5 SD below the norm on delayed recall composite score and 2 tests ≥1.5 SD below the norm in any one domain other than memory. Non-amnestic MCI single domain was defined as 2 tests ≥1.5 SD below the norm in any one domain other than memory. Non-amnestic MCI single domain was defined as 2 tests ≥1.5 SD below the norm in any one domain other than memory and 1 test ≥1.5 SD below the norm in an additional domain other than memory.