Research Paper|Volume 13, Issue 18|pp 22078—22091

The relationship between plasma free fatty acids, cognitive function and structural integrity of the brain in middle-aged healthy humans

Markus Herrmann¹, Sebastian Simstich¹, Günter Fauler¹, Edith Hofer^2,³, Eva Fritz-Petrin¹, Wolfgang Herrmann⁴, Reinhold Schmidt²

¹Clinical Institute of Medical and Chemical Laboratory Diagnostics, Medical University of Graz, Graz, Austria
²Clinical Division of Neurogeriatrics, Department of Neurology, Medical University of Graz, Graz, Austria
³Institute for Medical Informatics, Statistics and Documentation, Medical University of Graz, Graz, Austria
⁴Medical School, Saarland University, Homburg/Saar, Germany

Received: July 5, 2021Accepted: September 7, 2021Published: September 23, 2021

https://doi.org/10.18632/aging.203573

Copyright: © 2021 Herrmann 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

Background: The cerebral composition of ω-3 and ω-6 polyunsaturated fatty acids (PUFAs) is believed to influence cognitive function and structural damage of the aging brain. However, existing data is inconsistent.

Materials and Methods: This retrospective study explored the association between free plasma PUFA concentrations, cognitive function and brain structure atrophy in a well-characterized community-dwelling cohort of elderly individuals without stroke and dementia. Ten different fatty acids were analyzed in stored plasma samples from 391 non-demented elderly individuals by gas chromatography mass spectrometry. Neuropsychiatric tests capturing memory, executive function and visuopractical skills were performed in all participants. Brain atrophy was assessed by MRI in a subset of 167 individuals.

Results: Higher plasma concentrations of free ω-6 PUFAs (p = 0.042), and, in particular, linoleic acid (p = 0.01), were significantly associated with lower executive function. No significant association existed between ω-3 PUFA concentrations and cognitive functioning. The volume of the frontal lobes was inversely associated with ω-6 PUFAs, whereas ω-3 PUFAs were positively related with temporal lobe volumes. All associations did not withstand correction for multiple comparisons.

Conclusions: Our study suggests subtle effects of PUFA imbalances on cognition and brain structure. Yet the observed associations are weak and unlikely to be of clinical relevance. The brain regions that seem to be most sensitive to imbalances of ω-3 and ω-6 PUFAs are the frontal and temporal lobes.