Parkinson disease psychosis: Update.

Area of Science:

• Neurology
• Psychiatry

Background:

• Psychotic symptoms, including visual hallucinations and delusions, are prevalent in Parkinson's disease (PD) patients undergoing treatment.
• These symptoms significantly impact patient and caregiver well-being, often leading to nursing home placement and indicating a poor prognosis, including increased mortality and potential dementia.
• Current treatment options for psychosis in PD (PDP) are limited, with significant challenges in managing these symptoms effectively without exacerbating motor deficits.

Purpose of the Study:

• To review the current understanding and treatment landscape of psychotic symptoms in Parkinson's disease.
• To evaluate the efficacy and safety of available pharmacological interventions for PDP.
• To highlight the unmet needs and challenges in managing PDP.

Main Methods:

• Literature review of studies on Parkinson's disease psychosis.
• Analysis of evidence for pharmacological treatments, including clozapine, quetiapine, other antipsychotics, and cholinesterase inhibitors.
• Examination of clinical trial data and expert recommendations.

Main Results:

• Clozapine is the only antipsychotic with Level A evidence for treating PDP, regardless of dementia status.
• Quetiapine, while deemed safe in trials, has not demonstrated efficacy for PDP.
• Other antipsychotic medications may worsen motor function in PD patients, and evidence for cholinesterase inhibitors is limited.

Conclusions:

• Parkinson's disease psychosis (PDP) is a complex and serious condition with a significant impact on patients and their families.
• Effective treatment options for PDP are scarce, posing a considerable clinical challenge.
• Clozapine remains the primary evidence-based treatment, while other agents have limited or unproven efficacy and potential risks.