A neuroimaging measure to capture heterogeneous patterns of atrophy in Parkinson’s disease and dementia with Lewy bodies

Abstract

AbstractINTRODUCTIONParkinson’s disease (PD) and Dementia with Lewy bodies (DLB) show heterogeneous brain atrophy patterns and common group-average analyses are limited in capturing individual differences. Neuroanatomical normative modelling overcomes this by comparing individuals to a large reference cohort.METHODSWe generated z-scores from T1w-MRI scans for each participant (108 PD; 61 DLB) relative to normative regional cortical thickness and subcortical volumes, modelled in a reference cohort (n=58,836). Outliers (z<-1.96) were aggregated across 169 brain regions per participant. We examined total outlier counts between high versus low visual performance in PD; and PD versus DLB; and tested associations between these and cognition.RESULTSWe found greater total outlier counts in PD poor visual performers, compared to high; and in DLB versus PD. Outlier counts were associated with global cognition in DLB, and visuoperception in PD.DISCUSSIONNeuroanatomical normative modelling shows promise as a clinically informative technique in PD and DLB.