Dietary and Lifestyle Factors of Brain Iron Accumulation and Parkinson's Disease Risk

BackgroundAlterations in brain iron accumulation, representing both excess or insufficiency of iron, are associated with Parkinsons disease. Iron is exclusively absorbed from food; therefore, dietary patterns may impact risk. ObjectiveAssess associations between dietary preferences, brain iron, and Parkinsons disease risk. MethodsThis study included 228,653 individuals and utilized dietary surveys, magnetic resonance imaging, and electronic health records of neurological diagnoses. We performed regression analyses using i) estimated dietary nutrient intake, ii) dietary preferences, and iii) a lower-dimensional space factor-loading dietary preferences to predict a novel brain iron accumulation score derived from T2-weighted MRI and Parkinsons disease diagnosis. ResultsWe found strong positive associations between measures of brain iron accumulation and the alcohol factor (t=4.02, pFDR<0.001) and significant negative associations between brain iron accumulation and the high-sugar factor (t=-3.73, pFDR<0.001). Conversely, the alcohol factor was associated with decreased Parkinsons disease risk (t=-5.83, p <1x10-8) and the high-sugar factor was associated with increased Parkinsons disease risk (t=6.03, p <1x10-8). Instrumental variable regression revealed that dietary preferences associated with higher brain iron were also associated with lower risk for Parkinsons disease ({square}=-0.247, p=0.004). Voxel-wise imaging analysis displayed iron accumulation patterns consistent with these findings. ConclusionContrary to some prior studies, we find lower central iron levels to be associated with greater Parkinsons disease risk. Dietary components, especially alcohol and carbohydrates, are related to differences in brain iron accumulation in motor regions of the brain and differences in risk of Parkinsons disease, suggesting the potential for dietary interventions to influence Parkinsons disease risk. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=145 SRC="FIGDIR/small/24304253v3_ufig1.gif" ALT="Figure 1"> View larger version (35K): org.highwire.dtl.DTLVardef@297e0dorg.highwire.dtl.DTLVardef@12c102org.highwire.dtl.DTLVardef@13d8503org.highwire.dtl.DTLVardef@1e7a657_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOGraphical Abstract:C_FLOATNO Dietary and Lifestyle Factors of Brain Iron Accumulation *Previous research has established that iron overload in the brain is associated with increased risk of movement disorders.4-7 C_FIG