(OR04-01-24) Reduced Dementia Risk That Originated From Protective Effect of Dietary Biotin on Brain Structure: Evidence From a Large-Population Based Cohort Study

Objectives: Although animal models suggested biotin to be a neuroprotective factor, there is a scarcity of population-based studies.

Methods: Derived from UK Biobank, this study included 210864 participants. Dietary biotin was based on 24h dietary recall, and divided into low, moderate, and high groups by tertiles. Time-varying Cox models were used to estimate the hazard ratios (HRs) for the associations of dietary biotin with risk of all-cause dementia, Alzheimer's disease (AD), vascular dementia (VD), early-onset dementia (EOD), and delayed-onset dementia (DOD). Restricted cubic splines were established to investigate the non-linear association. Stratified analyses were performed by sex, Townsend Deprivation Index (TDI) and polygenic risk score (PRS). Mediation effect of chronic diseases and blood biomarkers (metabolizers, immunologic factors, hormonal indicators, etc) were examined. We employed linear regression models to estimate the β coefficients for associations of dietary biotin with brain structure, including 1) volume of total brain, white matter, grey matter and white matter hyperintensities (WMHs); 2) subcortical volumes (caudate, thalamus, putamen, amygdala and hippocampus); and 3) hippocampal subfields.

Results: Compared with low group, moderate (HR = 0.76 [0.67-0.85]) and high (HR = 0.73 [0.63-0.83]) group had a decreased all-cause dementia risk; result remained robust stratified by sex and TDI, but was only significant among those with high PRS. Similar results were found for DOD and AD. However, no significant association was observed for EOD, and only moderate biotin intake was associated with declined VD risk. Non-linear association existed. Despite no mediated effect from chronic diseases and blood biomarkers, interestingly, dietary biotin was associated with brain structure. Specifically, moderate and high group had less volume of whole brain, grey matter, and white matter; moderate group was associated with lower WMHs. Additionally, moderate and high group were associated with larger volume of caudate, thalamus, putamen, amygdala, hippocampus and several hippocampal subfields, all of which were highly involved in dementia development.

Conclusions: Dietary biotin serves as a defender for dementia prevention, which may originate from the neuroprotection on brain structure.

Funding Sources: There was no funding source.