%0 Journal Article %J J Alzheimers Dis %D 2018 %T Associations of Dietary Protein and Fiber Intake with Brain and Blood Amyloid-β. %A Fernando, W M A D Binosha %A Rainey-Smith, Stephanie R %A Gardener, Samantha L %A Villemagne, Victor L %A Burnham, Samantha C %A Macaulay, S Lance %A Brown, Belinda M %A Gupta, Veer Bala %A Sohrabi, Hamid R %A Weinborn, Michael %A Taddei, Kevin %A Laws, Simon M %A Goozee, Kathryn %A Ames, David %A Fowler, Christopher %A Maruff, Paul %A Masters, Colin L %A Salvado, Olivier %A Rowe, Christopher C %A Martins, Ralph N %K Aged %K Alzheimer Disease %K Amyloid beta-Peptides %K Australia %K Biomarkers %K Brain %K Cognition %K Cohort Studies %K Cross-Sectional Studies %K Dietary Fiber %K Dietary Proteins %K Female %K Humans %K Logistic Models %K Male %K Middle Aged %K Neuropsychological Tests %K Positron-Emission Tomography %X

Accumulating evidence suggests a diet high in protein and fiber may confer some protection against Alzheimer's disease (AD). However, no human studies to-date have assessed the relationship between protein and fiber intake, and plasma and brain amyloid-β (Aβ). Consequently, this cross-sectional study, investigated the association of self-reported dietary intakes of protein and fiber, with plasma and brain Aβ burden (n = 541, and n = 162 respectively), in a well-characterized cohort of cognitively normal older adults, drawn from the larger Australian Imaging, Biomarkers and Lifestyle (AIBL) study of aging. We observed 12.59 and 8.43 higher odds of 'high' brain Aβ burden (PiB PET SUVR≥1.5) if protein intake fell in the lowest and middle tertile, respectively, compared to the highest tertile (p = 0.008; p = 0.013). Thus, in this cohort, the more protein consumed, the less likelihood of 'high' Aβ burden in the brain. No other significant associations were observed. The results of this study highlight the potentially protective impact of high dietary protein intake on brain Aβ burden in older adults, before objective memory decline is apparent. While longitudinal validation is required, these findings may assist in the development of dietary approaches aimed at preventing or delaying AD onset.

%B J Alzheimers Dis %V 61 %P 1589-1598 %8 2018 %G eng %N 4 %1 http://www.ncbi.nlm.nih.gov/pubmed/29376865?dopt=Abstract %R 10.3233/JAD-170742 %0 Journal Article %J J Alzheimers Dis %D 2017 %T Increased Carbohydrate Intake is Associated with Poorer Performance in Verbal Memory and Attention in an APOE Genotype-Dependent Manner. %A Gardener, Samantha L %A Rainey-Smith, Stephanie R %A Sohrabi, Hamid R %A Weinborn, Michael %A Verdile, Giuseppe %A Fernando, W M A D Binosha %A Lim, Yen Ying %A Harrington, Karra %A Burnham, Samantha %A Taddei, Kevin %A Masters, Colin L %A Macaulay, Stuart L %A Rowe, Christopher C %A Ames, David %A Maruff, Paul %A Martins, Ralph N %X

Evidence suggests that a diet low in carbohydrates can impact on cognitive performance among those with Alzheimer's disease (AD). However, there is a lack of data assessing this relationship among cognitively normal (CN) older adults at increased future risk of developing AD due to carriage of the apolipoprotein E (APOE) ɛ4 allele. We assessed the cross-sectional association between carbohydrate intake, cognitive performance, and cerebral amyloid-β (Aβ) load in CN older adults, genotyped for APOEɛ4 allele carrier status. Greater carbohydrate intake was associated with poorer performance in verbal memory in APOEɛ4 allele non-carriers, and poorer performance in attention in APOEɛ4 allele carriers. There were no associations between carbohydrate intake and cerebral Aβ load. These results provide support to the idea that decreasing carbohydrate intake may offer neurocognitive benefits, with specific cognitive domains affected in an APOE genotype-dependent manner. These findings warrant further investigation utilizing a longitudinal study design.

%B J Alzheimers Dis %V 58 %P 193-201 %G eng %N 1 %R 10.3233/JAD-161158