Understanding Neurocognitive Disorders in Parkinson’s Disease
Neuropsychiatry • Movement Disorders • Cognitive Care
Understanding Neurocognitive Disorders in Parkinson’s Disease
Parkinson’s Disease (PD) is a progressive neurodegenerative disorder that affects movement, cognition and behaviour. This Emocare guide details the neurocognitive changes seen in PD, from mild cognitive impairment to Parkinson’s disease dementia, along with assessment strategies and multidisciplinary management.
What are Neurocognitive Disorders in Parkinson’s Disease?
Neurocognitive impairment in PD results from degeneration of dopaminergic, cholinergic and frontostriatal networks. Cognitive changes range from Parkinson’s Disease Mild Cognitive Impairment (PD-MCI) to Parkinson’s Disease Dementia (PDD). Domains commonly affected include attention, executive function, visuospatial ability and memory.
Core cognitive features
- Executive dysfunction — impaired planning, flexibility and problem solving.
- Attention deficits and slowed cognitive processing.
- Visuospatial impairment — difficulty navigating, judging distances, mental rotation.
- Memory impairment — inefficient retrieval rather than storage failure.
- Language changes — reduced fluency, word-finding difficulty.
- Impaired dual-tasking (motor + cognitive simultaneous tasks).
Stages of cognitive decline in PD
- Normal cognition with PD: Subtle slowing, but largely intact function.
- PD-MCI: Mild deficits in one or more cognitive domains; minimal impact on daily functioning.
- Parkinson’s Disease Dementia (PDD): Significant cognitive impairment affecting independence, complex tasks and day-to-day functioning.
Neuropsychiatric and behavioural symptoms
- Depression and anxiety.
- Visual hallucinations and delusions (more common in advanced PD).
- Apathy and reduced initiative.
- Impulse control disorders (linked with dopamine agonist therapy).
- Sleep disturbances and REM sleep behaviour disorder.
Assessment — clinical and cognitive priorities
- Comprehensive neuropsychological evaluation (attention, executive function, visuospatial abilities, memory, language).
- Screening tools: MoCA, PD-Cognitive Rating Scale (PD-CRS).
- Assessment for hallucinations, delusions and mood disorders.
- Evaluate daily functioning — medication management, driving, financial decisions.
- Review dopaminergic medications that may worsen confusion or hallucinations.
- Monitor caregiver burden and provide early support.
Ethical, safety & care-planning considerations
- Driving safety assessments due to visuospatial and attentional deficits.
- Medication-induced psychosis risk must be monitored closely.
- Advance care discussions should begin early due to progressive cognitive decline.
Treatment — cognitive, behavioural and pharmacological care
Treatment focuses on optimising cognition, controlling behavioural symptoms and preserving functional independence through a multidisciplinary approach.
Cognitive & Functional Interventions
- Cognitive training for attention, visual-spatial processing and executive skills.
- Home modifications and visual cues to reduce complexity.
- Occupational therapy for task simplification and safety.
Behavioural Management
- Identify triggers for anxiety, hallucinations or agitation.
- Maintain structured routines and adequate sleep.
Pharmacological Management
- Cholinesterase inhibitors (e.g., rivastigmine) for dementia symptoms.
- Adjust dopaminergic medications if hallucinations or confusion emerge.
- Atypical antipsychotics (e.g., quetiapine) for psychosis when necessary.
Caregiver Support
- Provide psychoeducation on PD cognitive changes.
- Support groups and respite services.
Red flags — urgent actions
- Sudden confusion or acute cognitive decline.
- Severe hallucinations or delusions causing safety risks.
- Medication toxicity — excessive movement, confusion or agitation.
- Caregiver exhaustion affecting patient safety.
தமிழில் — சுருக்கம்
Parkinson’s Disease-இல் நினைவாற்றல், கவனம், முடிவெடுத்தல் மற்றும் பார்வை-விளக்கம் திறன்கள் மெதுவாக குறையலாம். இது PD-MCI முதல் Parkinson’s Dementia வரை வளரலாம். சிகிச்சை: மருந்து சரிசெய்தல், அறிவாற்றல் பயிற்சி, நடத்தை மேலாண்மை மற்றும் குடும்ப ஆதரவு.
Key takeaways
- PD affects cognition early through frontostriatal dysfunction.
- Visuospatial and executive deficits are hallmark symptoms.
- Medication review is critical as drugs may worsen psychosis or confusion.
- Multidisciplinary care improves independence and quality of life.