Regional grey matter volume correlates with anxiety, apathy and resilience in geriatric depression

Introduction Geriatric depression (GD) is associated with significant medical comorbidity, cognitive impairment and brain atrophy, premature mortality, and suboptimal treatment response. While apathy and anxiety are common comorbid symptoms in GD, resilience has been found to be a protective factor. Understanding the relationship between brain morphometry and symptoms and resilience in GD could inform clinical treatment targets. Gray matter volume (GMV) is altered in GD but correlations with mood symptoms and particularly resilience are less available. Methods Forty-nine older adults over 60 y.o. (38 women) diagnosed with major depressive disorder undergoing concurrent antidepressant treatment participated in the study. Depressive symptoms, as well as apathy, anxiety and resilience were assessed along with an anatomical T1-weighted MRI scan. We used a general linear model (GLM) to identify clusters in which GMV correlated with each measure. Freesurfer 6.0 was used to process T1-weighted images and perform voxel-wise whole-brain GLMs using age and sex as covariates. Partial Spearman correlations controlling for age and sex were used to investigate the association between clinical variables. Results Greater depression severity was, as expected, associated with greater anxiety (r=.53, p=.0001). Greater resilience was associated with lower depression (r=-.33, p=.03) and reduced apathy (r=.39, p=.01). Greater GMV in widespread, partially overlapping clusters across the brain was associated with reduced anxiety and apathy, as well as increased resilience. Conclusions Our results suggest that GMV in extended brain regions is a potential marker for resilience in GD and overlaps in specific smaller regions with GMV markers for depression and anxiety. Since resilience is a protective factor against depression, future studies should examine GMV changes in these regions with treatment. This research was funded by This work is partially supported by NIH grants AT009198 and AT008383 AT008383-04S to Dr. Lavretsky.