ausblenden:
Schlagwörter:
Waist-hip ratio; Mean diffusivity; DTI
Zusammenfassung:
Introduction:Dietary habits and obesity have been shown to
influence human brain structure and function. It is, however, unclear
if diet or obesity, measured using body-mass-index (BMI) and waist-
hip ratio (WHR), affects the microstructure of the hippocampus, a key
area involved in memory functions.
Objectives: This study explored whether dietary patterns are associated with BMI, WHR or hippocampal microstructure, measured
by diffusion tensor imaging (DTI) in non-demented elderlies.
Method / Design: Dietary patterns were identified using exploratory factor analysis on a food frequency questionnaire in 498 participants aged ≥ 60 years in the ongoing LIFE-study (Leipzig, Germany).
Individual hippocampal subfields were segmented on high-resolution
3T-magnetic resonance images in a subgroup (n = 190), using FreeSurfer (www.freesurfer.net). Hippocampal mean diffusivity (MD) of
each subfield was extracted on co-registered MD maps derived by
DTI, using FSL (www.fmrib.ox.ac.uk/fsl/). Dietary patterns, BMI,
WHR and MD were correlated using partial correlations adjusted for
important confounders.
Results: Factor analysis revealed a ‹red meat and high-sugar›
and a ‹fish, fruit and vegetable› pattern. The first pattern correlated to
WHR (r=0.30, p<0.01), whereas the second one negatively correlated
to WHR (r=-0.37 p<0.01). A higher WHR, but not BMI or dietary
patterns, correlated to higher MD, indicative of lower microstructural
integrity, on the CA2/3 region of the hippocampus (bilateral, r>0.17,
p<0.05).
Conclusions: We showed here that an unhealthy diet correlates
with central obesity, reflected in a higher WHR, which in turn is associated with lower microstructural integrity within specific areas of the
hippocampus, independent of confounders. Therefore, an unhealthy
diet might indirectly lead to hippocampal microstructural changes via
its negative contribution to central obesity. Upcoming analyses now
need to clarify if the microstructural changes in hippocampus translate into changes in memory performance, and if dietary interventions
could potentially reverse these effects. This might help to develop
novel strategies for maintaining brain health.
