Apathy in Parkinson's disease: Diagnostic and etiological dilemmas§


  • Sergio E. Starkstein MD, PhD

    Corresponding author
    1. Department of Psychiatry and Clinical Neurosciences, University of Western Australia and Fremantle Hospital, Fremantle, Western Australia, Australia
    • Education Building T-7, Fremantle Hospital, Fremantle, 6959 WA, Australia
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  • Funding agencies: This article was supported by grants from the Australian National Health and Medical Research Council, and by the Michael J. Fox Foundation for Parkinson Research.

  • Relevant conflicts of interest/financial disclosures: Nothing to report.

  • §

    Full financial disclosures and author roles may be found in the online version of this article.


About one-third of patients with Parkinson's disease (PD) are diagnosed with apathy in cross-sectional studies. However, once patients with concomitant depression and dementia are excluded, the frequency of apathy drops to 5% to 10%. Several scales have been recommended to rate apathy in PD, but specific psychiatric interviews have not been developed, and recently proposed standardized diagnostic criteria are still in the validation process. Most studies assessing the association between subthalamic deep brain stimulation (STN-DBS) and apathy have reported a relative increase in the frequency and severity of apathy, although discrepant findings have also been reported. Several mechanisms to explain apathy in PD have been proposed, from dopaminergic imbalances in frontal-basal ganglia circuits to dysfunction of nondopaminergic circuits and the cingulate gyrus. Future studies should provide reliable and valid instruments to diagnose apathy in PD, and should examine the mechanism of apathy accounting for relevant confounders, such as depression and cognitive deficits, and important contextual factors. Finally, treatment for apathy in PD should not be restricted to psychoactive drugs, but should also include nonpharmacological techniques such as psychotherapy and occupational therapy. © 2012 Movement Disorder Society