Abstract WP494: Neuroimaging Correlates of Apathy in Late-Onset Depression

Abstract

Apathy is prevalent in older depressed patients and considered to be a predictor of increased dementia risk. Neuroimaging characteristics of late-life depression are being discussed. However, it is unclear whether apathetic (ApD) and nonapathetic depression (D) have different neuroimaging correlates. The objective of this study was to examine structural and functional bases of ApD by using morphometric and functional connectivity MRI analyses. We enrolled 45 consecutive patients with late-onset depression (85% female; mean age=66 (4) years, mean education=14 (2) years) and 22 age and gender-matched healthy elderly. Patients were divided into ApD (n=26) and D (n=19) groups based on Apathy Scale scores. All the participants underwent 1.5 T structural MRI and resting-state fMRI. Fazekas scale was used to quantify white matter hyperintensities. Demographic data, Hamilton Depression Rating Scale (HAMD), Apathy Scale, and MoCA scores for the three groups were compared. Association between apathy, depression and neuroimaging characteristics was assessed using regression analysis with demographic and cognitive variables included as covariates. ApD patients demonstrated nonsignificantly higher HAMD and Fazekas scores and lower MoCA scores compared to D patients. The latter group showed similar Fazekas and slightly lower MoCA scores vs healthy elderly. After controlling for covariates, apathy was significantly associated with volumes of nucleus caudatus and putamen on the right as well as functional connectivity between anterior cingulate and parahippocampal gyrus. Depression correlated with the volumes of the cerebral and cerebellum cortices as well as functional connectivity of salience resting state network. Our study demonstrated an association between volumes of basal ganglia, functional connectivity of anterior cingulate and apathy in late-onset depression.