title: Review of delirium in patients with Parkinson's disease.
abstract: Parkinson's disease (PD) is common and has a number of associated neuropsychiatric disturbances. Of these, delirium has historically been under-recognised. Delirium is an acute disturbance of attention and awareness that fluctuates, and is accompanied by an additional disturbance of cognition. As delirium is known to carry a particularly poor prognosis in terms of morbidity and mortality, and the relationship between delirium and dementia is becoming better defined, we completed a literature review of delirium in the context of PD. A literature search was completed using the databases PubMed, Embase and Ovid Medline. PubMed (1945-2014) was searched in September 2014; Embase (1974-2014); and Ovid Medline (1946-2014) in October 2014. The search terms 'delirium' and 'Parkinsons' in combination were used. Large studies using a robust definition of delirium were lacking in PD. There is the suggestion that PD is a risk factor for delirium and that delirium negatively impacts upon the motor symptom trajectory. Deficits in the neurotransmitters dopamine and acetylcholine are implicated in the pathophysiology of delirium in PD. Systemic inflammation also appears to have a role. Treatment of delirium in PD should include medication review and cautious use of atypical antipsychotics where pharmacological treatment is indicated. Of the atypical antipsychotics studied, quetiapine has the least extrapyramidal side effects. Evidence suggests a specific link between delirium and PD but well-designed clinical studies to evaluate the prevalence, impact and treatment of delirium in PD are required. Given the potential to improve outcomes through delirium prevention we conclude that delirium in PD is an area worthy of further study.
authors.affiliation: Department of Older Peoples Medicine, Freeman Hospital, Newcastle upon Tyne Hospitals NHS Foundation Trust, Freeman Rd, Newcastle upon Tyne, Tyne and Wear, NE7 7DN, UK. emma.vardy@newcastle.ac.uk.|Institute of Neuroscience and Newcastle University Institute for Ageing, Newcastle University, Newcastle upon Tyne, NE4 5PL, UK. emma.vardy@newcastle.ac.uk.
authors.forename: Emma R L C
authors.initials: ER
authors.lastname: Vardy
authors.affiliation: School of Medical Education, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK.|Northumberland Tyne and Wear NHS Foundation Trust, Campus for Ageing and Vitality, Newcastle upon Tyne, UK.
authors.forename: Andrew
authors.initials: A
authors.lastname: Teodorczuk
authors.affiliation: Department of Older Peoples Medicine, Freeman Hospital, Newcastle upon Tyne Hospitals NHS Foundation Trust, Freeman Rd, Newcastle upon Tyne, Tyne and Wear, NE7 7DN, UK.|Institute of Neuroscience and Newcastle University Institute for Ageing, Newcastle University, Newcastle upon Tyne, NE4 5PL, UK.
authors.forename: Alison J
authors.initials: AJ
authors.lastname: Yarnall
mesh_terms: D015897:Comorbidity; D003693:Delirium / Q000188:drug therapy / Q000453:epidemiology / Q000209:etiology; D006801:Humans; D010300:Parkinson Disease / Q000150:complications / Q000453:epidemiology
keywords: Cognition; Delirium; Parkinson’s disease; Pathology; Prevalence; Treatment