Edinburgh Imaging

MSc projects 1314 004

Neuroimaging correlates of depression in Parkinson’s disease: A systematic literature review.


One third of all Parkinson's disease (PD) patients may present with some form of depression during the disease course, with a 47% prevalence of depression, while almost 50% of depressed PD patients (PDD) fulfill the criteria for a major depressive episode. Depression in PDD is predictive of a more rapid progression in cognitive and motor impairment, and thus heralds early detection and treatment. Currently, neuroimaging findings are both conflicting, and inadequate. The fact that depression affects similar areas with PD, further complicates the picture. A systematic literature review was performed to critically evaluate current knowledge around PDD. Results have shown several design flaws in most neuroimaging studies (namely MRI, DTI, PET, SPECT, TCS, CSF), suggesting a lack of coherence within and between studies. Findings are contradictory, and rarely supplementary, though similar areas are implicated (Basal Ganglia, Limbic System, Mesenchepalic midline, as well as both dopaminergic and serotonergic imbalances). Areas of improvement are suggested for future research, whereby the construct of depression will be clearly defined, diagnosed with valid measures, with adequate blinding, adequate sample sizes if possible, and otherwise well matched subjects. Cross-modality imaging may also be beneficial, while neuroimaging research may benefit from a more clear reasoning behind a choice to utilize one technique or another or such as regarding radioligands utilized. In order to clarify the multifocal etiology of affective symptomatology in PD patients, aiming at the improvement of the pharmacological treatment of these patients, future research must aim to identify culprits in the morphological, functional, and chemical level. In this manner the progression of depression by intervening as early as possible can be achieved.

Project type:
  • Literature review
  • Systematic review
Imaging keywords:
Application / disease keywords:
  • Basal Ganglia
  • Limbic System
  • Mesenchepalic midline
  • Parkinson's disease (PD)
  • 13-14
Associated publication(s):
  • Diamantoudi M et al., Neuroimaging correlates of depression in parkinson’s disease: a systematic literature review. 10th Inter’l Cong Non-Motor Dysfunct PD & Related Disor. 2014.12.04-07.