Journal watch: The neuropsychiatry of Parkinson's disease: advances and challenges

Journal watch: The neuropsychiatry of Parkinson’s disease: advances and challenges

850 567 Maggie Ford, MD
The Background

Although Parkinson’s disease (PD) is well known for its motor symptoms its associated neuropsychiatric symptoms should not be overlooked.1 Neuropsychiatric symptoms are common in all stages of PD, can increase over time,2 and are clinically important.1 Furthermore, the severity and disability caused by neuropsychiatric symptoms can be on par with those caused by motor symptoms.1

 

The Objective

This review article provides an overview of the correlates, risk factors, assessment tools, treatments, neurobiology, and challenges related to the neuropsychiatry of PD.1

 

The Strategy

Weintraub D et al. accessed MEDLINE via PubMed to find peer-reviewed articles on PD and neuropsychiatric disorders.1 They searched for English-language articles published between January 1, 2015 and June 13, 2021 using several medical subject heading search terms.1 Additionally, the search strategy and selection criteria were limited to only include systemic reviews.1

 

The Findings

The neuropsychiatric signs and symptoms of PD can be split into three categories: affect, perception and thinking, and motivation.1 In the category of affect, clinically significant symptoms of depression and anxiety appear in 30–35% of patients with PD.3 For perception and thinking disturbances, in 25–40% of patients with PD minor psychosis occurs,4 and as reported by Weintraub D et al. is  “associated with high risk of hospitalisation, placement in long-term care, and increased in mortality”.1 In the area of motivation, studies have shown that apathy occurs in 35–40% of patients with PD.5,6 Also in the area of motivation, impulse control disorders have an incidence rate of 46% over 5 years.7 Of note, the onset of impulse control disorders can vary as they depend on the presence of dopaminergic treatment.1

Correlates and risk factors for the neuropsychiatric signs and symptoms that are present in PD overlap (Figure 1).1

Figure 1. Correlates and risk factors for the presence of neuropsychiatric signs and symptoms of PD1

There are several screening/assessment tools that can be used for the assessment of depression, anxiety, apathy, psychosis, and impulse control disorders in PD.1 However the sensitivity of these screening/assessment tools range from 66% to 100%, while the specificities range from 60% to 100%.1 The authors recommend assessing for neuropsychiatric signs and symptoms in patients with PD every 6–12 months.1

Treating the neuropsychiatric signs and symptoms in PD as well as understanding their neurobiology were both described as unmet needs by Weintraub D et al.1 Current research mostly focuses on pharmacologic treatments and depression.1 Few studies exist on anxiety, psychosis, impulse control disorders, or non-pharmacologic therapies.1 The neurobiology of neuropsychiatric illness in PD is not fully understood, however it is known to be a complex interaction of biological processes (neurodegeneration, neurotransmitter dysregulation, and dysfunction in neuronal circuitries).1

 

The Future

Further research is needed on the neuropsychiatry of PD to improve assessment, treatment, and awareness.1 Moreover, research is also needed to increase knowledge of the natural history and burden of disease.1 This future research may spur the development of specially designed training programs geared towards neuropsychiatric disease in patients with PD, leading the way for novel multidisciplinary care models.1

 

The Conclusion

PD is a disorder that can commonly have complex neuropsychiatric signs and symptoms, and because existing research is limited more studies are needed on this intricate topic.1

 


References
  1. Weintraub D et al. Lancet Neurol. 2022;21(1) :89–102.
  2. Kim R et al. J Neurol Sci. 2020;418:117157.
  3. Broen MP et al. Mov Disord. 08 2016;31(8):1125–33.
  4. Fénelon G et al. Mov Disord. Apr 30 2010;25(6):763–6.
  5. Santangelo G et al. Behav Neurol. Jan 01 2013;27(4):501–13.
  6. den Brok MG et al. Mov Disord. May 2015;30(6):759–69.
  7. Corvol JC et al. Neurology. 07 17 2018;91(3):e189-e201.

 

Brainwork is supported by unrestricted grants from: