Affective disorders in Parkinsonʼs disease

Abstract

Purpose of review-This review explores recent literature pertaining to affective disorders associated with Parkinson's disease.Recent findings-Nonmotor symptoms including affective disorders are becoming more widely recognized as complications of Parkinson's disease. As awareness of these symptoms increases, and new neuroimaging tools are developed and become more accessible, more studies are being conducted pertaining to behavioral complications in Parkinson's disease. The functional connectivity of the basal ganglia can predispose people with Parkinson's to develop affective disorders. Furthermore, dopaminergic treatments may exacerbate or trigger behavioral symptoms. It is now understood that changes associated with Parkinson's disease are widespread, affecting striatal and extrastriatal regions and resulting in alterations in gray matter, white matter, blood flow, metabolism, and dopaminergic and serotonergic function. Summary-Neuroimaging is advancing our knowledge of the mechanisms involved inParkinson's disease, and their role in the development of behavioral disorders. An increased understanding of these disorders may lead to the discovery of new therapeutic targets, or the identification of risk factors for the development of these disorders. If preventive therapies become available, identification of risk factors will be important for the identification and treatment of susceptible individuals.

Molecular imaging to track Parkinson's disease and atypical parkinsonisms: New imaging frontiers

“…The serotonergic alteration in depression was confirmed by another PET study using 18 F‐MPPF, a selective serotonin 1A receptor antagonist . Apathy may also occur in up to 40% of PD patients, and, although clinically distinct from depression, the two are often comorbid . Anatomical and imaging reports have provided evidence that network abnormalities within the prefrontal‐striatal circuit can lead to an apathetic behavior.…”

“…76 Apathy may also occur in up to 40% of PD patients, and, although clinically distinct from depression, the two are often comorbid. 72 Anatomical and imaging reports have provided evidence that network abnormalities within the prefrontal-striatal circuit can lead to an apathetic behavior. Classically, apathy is the result of a disruption of "emotional-affective" mechanisms linked to the ventral striatum, ventromedial prefrontal cortex, and amygdala.…”

“…There is evidence of a behavioral spectrum disorder ranging from hypodopaminergic levels responsible for apathy, anxiety, and depression, as described in the withdrawal dopaminergic syndrome to hyperdopaminergic syndrome, including impulse control disorders (ICDs), hallucinations, and psychosis . Often, depression may manifest before the diagnosis of PD; however, there is considerable evidence suggesting that this complication can be associated with a more widespread neurodegenerative process.…”

The Gut–Brain Axis and Its Relation to Parkinson’s Disease: A Review

“…Individuals with PD also commonly experience comorbid affective disorders such as anxiety, depression, and apathy (Aminian and Strafella, 2013). While no studies specific to PD have investigated treatment of these concurrent conditions by targeting the gut-brain axis, others have been conducted for different neurological disorders.…”