Impaired frontal executive function and predialytic chronic kidney disease.

OBJECTIVES: To investigate the nature of frontal dysfunction associated with chronic kidney disease (CKD) in people without stroke or depressive disorders.
DESIGN: Cross-sectional.
SETTING: Community based. PARTICIPANTS: Five hundred twenty-nine community-dwelling participants. MEASUREMENTS: Participants with CKD were classified into one of three diagnostic groups based on their estimated glomerular filtration rate (eGFR): normal (≥ 60.0 mL/min per 1.73 m(2)), mild CKD (45.0-59.9 mL/min per 1.73 m(2)), or moderate to severe CKD (<45.0 mL/min per 1.73 m(2)). Cognitive function was assessed using the Korean version of the Consortium to Establish a Registry for Alzheimer's Disease Neuropsychological Assessment Battery, lexical fluency, digit span test, and the 64-card Wisconsin Card Sorting Test.
RESULTS: Perseverative responses and perseverative errors were significantly more prevalent in the group with moderate to severe CKD than in those without CKD and those with mild CKD. The mean number of perseverative responses was 28.6 ± 16.9 in participants with moderate to severe CKD, 19.0 ± 11.4 in those with mild CKD, and 17.1 ± 10.6 in those without CKD (P < .001, ANCOVA). The mean number of perseverative errors was 23.1 ± 12.3 in participants with moderate to severe CKD, 16.2 ± 8.3 in those with mild CKD, and 14.8 ± 7.8 in those without CKD (P < .001, analysis of covariance). The odds ratios in the fully adjusted model for the presence of moderate to severe CKD for perseverative responses and perseverative errors were 4.82 (95% confidence interval (CI) = 2.14-10.85, P < .001) and 5.01 (95% CI = 2.22-11.28, P<.001), respectively.
CONCLUSION: Frontal dysfunction, particularly perseverative errors and responses, was associated with moderate to severe CKD in the population studied.