Apathy in depression: a morphometric analysis

Abstract

To study structural correlates of apathy in patients with late-life depression. Thirty-five patients (≥60 y.o.) with late-onset depression and 22 age-matched healthy volunteers underwent high resolution brain MRI-scanning, and a comprehensive neuropsychiatric examination including HAM-D and the Apathy Scale. A morphometric analysis showed that apathy was associated with atrophy of the lateral prefrontal cortex and reduced grey matter volume of the caudate nucleus on the right, and the nucleus accumbens on the left. Depression correlated with reduced thickness of the medial orbitofrontal cortex bilaterally, rostral anterior cingulate gyrus on the left, isthmus cingulate gyrus on the right, and larger surface area of the entorhinal cortex. Total grey matter volume, grey/white matter volumes of the cerebellum, and cortical thickness in temporal and occipital regions were negatively correlated with both apathy and depression severity. Thus, atrophy of basal ganglia and lateral prefrontal cortex, well known neuroanatomical correlates of apathy in different psychiatric and neurological conditions, characterized it in late-life depression too. This supports the idea of independent pathophysiology of apathetic syndrome.