43 REDUCED KIDNEY FUNCTION IS ASSOCIATED WITH POORER GLOBAL AND DOMAIN-SPECIFIC COGNITIVE PERFORMANCE IN COMMUNITY-DWELLING OLDER ADULTS

Abstract

Abstract Background Chronic Kidney Disease (CKD) is an important risk factor in the development of cognitive impairment. However, the association between reduced estimated Glomerular Filtration Rate (eGFR) and performance on domain-specific cognitive and neuropsychological assessments is less clear and may represent an important target in the promotion of optimal brain health in older adults. Methods Participants from the Trinity, Ulster and Department of Agriculture cohort study underwent detailed assessment of cognitive and neuropsychological function using the Mini-Mental State Examination (MMSE), Frontal Assessment Battery (FAB) and Repeatable Battery for Assessment of Neuropsychological Status (RBANS). Mixed-effects Poisson and linear regression was used to assess the relationship between eGFR strata and cognitive/neuropsychological test performance. Results 4,887 participants were included (73.94 ± 8.25 years; 67.7% female). Reduced eGFR was associated with poorer performance on all three cognitive assessments, most pronounced in those with eGFR <45 mL/mL/1.73m2 (IRR: 1.19; 95% CI: 1.09, 1.29; p < 0.001 for MMSE/IRR: 1.14; 95% CI 1.04, 1.24; p < 0.001 for the FAB/β: -3.23; 95% CI -5.18, −1.30; p = 0.001 for RBANS, fully adjusted). Reduced eGFR was associated with poorer performance on immediate memory, visual–spatial and attention RBANS domains. Associations were strongest in the youngest old (<70 years) with no association observed in those aged >80 years. Conclusion Reduced kidney function was associated with poorer global and domain-specific function in community-dwelling older adults. Associations were strongest for those with eGFR <45 mL/min/1.73m2 and the youngest-old, suggesting that this group may be most at risk and may benefit from potential preventative interventions.