Findings from MRI studies in late onset depressio

Abstract

Late onset depression is characterised by a first episode of depression after the age of 65 years old in elderly
patients. Since the era of Gaupp who was the first to introduce the role of vascular lesions in emotional
dysregulation and depression a lot of research has been performed in the field. The use of non-invasive
MRI techniques for grey and white matter changes has facilitated research during the past decades. The
underlying pathophysiological mechanism of depression in the elderly still remains unclear. We will describe
most important neuroimaging research performed in the field during the last decades. Existing literature
proposes three main pathways: 1. Acute vascular damage through stroke resulting to an interruption of
projections ascending from midbrain and brainstem. 2. Vascular burden accumulation reflected by white
matter fiber tract disruption and cognitive changes. 3. Neurotoxicity of depression as in other medical
chronic diseases having as a consequence a hippocampal volume loss.
We will briefly refer to the comorbidity of late-life depression with vascular dementia and Alzheimer’s
disease. Despite the large number of MRI studies it is difficult to draw concrete conclusions concerning the
underlying pathophysiological mechanisms of LOD.
Literature of neuropathology in this field remains sparse. The need for more neuropathological data as well
the integration of psychosocial factors in the explanation model remains indispensable.