Research Paper Volume 14, Issue 1 pp 240—252

Kidney function, brain morphology and cognition in the elderly: sex differences in the Austrian Stroke Prevention Study

Michael Kolland1, , Edith Hofer2,3, , Lukas Pirpamer2, , Daniela Eibl2, , Christian Enzinger4,5, , Alexander R. Rosenkranz1, , Reinhold Schmidt2, ,

  • 1 Department of Internal Medicine, Division of Nephrology, Medical University of Graz, Graz 8036, Styria, Austria
  • 2 Department of Neurology, Division of Neurogeriatrics, Medical University of Graz, Graz 8036, Styria, Austria
  • 3 Institute for Medical Informatics, Statistics and Documentation, Medical University of Graz, Graz 8036, Styria, Austria
  • 4 Department of Neurology, Division of General Neurology, Medical University Graz, Graz 8036, Styria, Austria
  • 5 Division of Neuroradiology, Interventional and Vascular Radiology, Department of Radiology, Medical University of Graz, Graz 8036, Styria, Austria

Received: November 11, 2021       Accepted: December 29, 2021       Published: January 13, 2022      

https://doi.org/10.18632/aging.203829
How to Cite

Copyright: © 2022 Kolland et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Abstract

Impaired kidney function is associated with structural brain changes and cognitive dysfunction. In the aging kidney, hemodynamic and structural alterations reduce the glomerular filtration rate (eGFR). Little is known about differences between men and women regarding decline of kidney function and brain damage.

In this community-based study, we assessed associations between the eGFR, focal and diffuse brain abnormalities and cognitive functions. Sex-specific effects were analyzed by interaction terms eGFR x sex on brain structure and cognition. Interactive effects were assessed using mixed-models –stratified by sex.

Overall, 196 women and 129 men (median age 68 years and mean eGFR 73.8±14.9 ml/min/1.73m2) were included. Significant associations existed between eGFR and cortical volume (β: 1.53E-04; SE: 6.72E-05; p=0.023 for neocortex). Sex exerted a significant interactive effect. Only in men, eGFR related to cortical volumes of all lobes and of deep gray matter structures (p= 0.001 for total gray matter, p=0.0004 for neocortex). In the whole group eGFR was not associated with cognition, but men with lower eGFR performed worse on tests for executive function, which, after FDR correction, was not significant.

We conclude, that in community-dwelling middle-aged and elderly individuals, reduced eGFR relates to brain volume loss in men but not in women.

Abbreviations

ASPS-Fam: Austrian Stroke Prevention Family Study; BMI: body mass index; CKD: chronic kidney disease; CKD EPI: Chronic Kidney Disease Epidemiology Cooperation; CRIC: Chronic Renal Insufficiency Cohort; DWI: diffusion weighted imaging; eGFR: estimated glomerular filtration rate; ESH/ESC: European society of hypertension, European society of cardiology; FDR: false discovery rate; FGF23: fibroblast growth factor 23; FLAIR: Fluid Attenuated Inversion Recovery; HDL: high density lipoprotein; IQR: interquartile range; LGT-3: Bäumler’s Lern- und Gedächtnistest; MPRAGE: magnetization-prepared rapid acquisition gradient-echo; MRI: magnetic resonance imaging; PSMD: peak width of skeletonized mean diffusivity; WHO: world health organisation; WMH: white matter hyperintensities.