Cognitive capacity in individuals with chronic kidney disease: relation to demographic and clinical characteristics

The life expectancy of individuals with Chronic Kidney Disease (CKD) on hemodialysis has increased, however, with over years in treatment, there is impairment of cognitive function that affect adherence to therapy and dialysis.

To evaluate the cognitive ability of individuals on hemodialysis through the Mini Mental State Examination (MMSE) and the relation to sociodemographic and clinical characteristics of these individuals.

We obtained demographic and clinical information of 75 individuals. To assess memory and cognition MMSE was applied, which was analyzed according to the different cutoff points proposed in the literature. After classifying the participants according to proposal of different studies, the causes of CKD and sociodemographic characteristics, individuals were divided into groups with and without cognitive impairment in an attempt to identify differences between them.

Most participants were men with a mean age of 59.2 years. The mean MMSE score was 24.16 points and there was no difference (p < 0.05) in MMSE results between the different causes of CKD. MMSE scores were correlated (p < 0.05) positively with years of schooling and income and inversely with age. According to the different cutoff points, six to 34 participants showed cognitive impairment and memory, and only three of these were classified with cognitive impairment for all cutoff points evaluated.

The average MMSE score declined with increasing age and increased with years of schooling and income per capita. No relationships were found to justify the harmful effects of dialysis process on cognition and memory.