Association of cognitive function with albuminuria and eGFR in the general population.

Background and Objectives: Recent studies found different associations of cognitive function with albuminuria or estimated GFR (eGFR). Most studies were limited to the elderly or did not take both renal variables into account. Therefore, this study analyzed the association of cognitive function with albuminuria and eGFR in community-dwelling persons aged 35 to 82 years.
Design, Setting, Participants, & Measurements: This was a cross-sectional study comprising 4095 participants of the Prevention of Renal and Vascular End-Stage Disease (PREVEND) study. Cognitive function, measured with the Ruff Figural Fluency Test (RFFT), was treated as the dependent variable, and albuminuria and eGFR were treated as independent variables.
Results: The prevalence of albuminuria <10, 10 to 29, and ≥30 mg/24 h was 54%, 31%, and 15%, respectively. Mean eGFR (± SD) was 79 ± 15 ml/min per 1.73 m(2). Because of interaction between albuminuria and age, analyses were performed per age tertile. After multivariate adjustment, albuminuria ≥ 30 mg/24 h, but not eGFR, was associated with lower RFFT score in the youngest tertile (B -5.3; 95% CI, -0.6 to -9.2; P = 0.05), but not in older tertiles. Moreover, subjects in the youngest tertile with increasing albuminuria (5-15 and >15 mg/24 h) before RFFT measurement had lower mean RFFT scores than subjects with stable albuminuria: mean difference -4.9 (P = 0.3) and -6.7 (P = 0.03), respectively.
Conclusions: In this community-based cohort, elevated albuminuria was associated with worse cognitive function in young but not in old persons. There was no association of eGFR with cognitive function.