Parkinson Disease Dementia
This article focuses on Parkinson Disease Dementia (PDD), a common condition in patients with Parkinson's disease. It details the prevalence of PDD, particularly in older patients with prolonged motor dysfunction, and contrasts the cognitive symptoms of PDD with those of Alzheimer's disease. The article also discusses the symptomatic treatment of PDD, noting the lack of therapies that modify the disease course. It outlines medical treatments, including cholinesterase inhibitors and memantine, and advises on discontinuing medications that could impair cognition.
Prevalence and Characteristics of Parkinson Disease Dementia
Dementia is common in Parkinson disease. Parkinson disease dementia (PDD) is present in 30% of patients and its prevalence increases with the duration of motor dysfunction in the disease. Older and severely affected patients are more prone to cognitive impairment in Parkinson disease. Also, those with sleep disorder, autonomic dysfunction, and gait dysfunction are more liable to dementia. Also, anticholinergic drugs often exacerbate cognitive deficits.
Differences Between PDD and Alzheimer Disease
PDD is different from that of Alzheimer disease (AD). It is commonly present as executive dysfunction, visuospatial dysfunction, with less prominent memory deficits and relatively preserved language function. Also, hallucinations, delusions, and behavioral symptoms are common in PD.
Treatment of Parkinson Disease Dementia
The treatment of PDD is mainly symptomatic. No therapies have been shown to modify the course of the disease or influence prognosis. Medical treatment includes cholinesterase inhibitors. They show mild benefit towards dementia and hallucinations.
Pharmacological Management of PDD
Pharmacological management of PDD includes donepezil and rivastigmine. Alternatively, memantine at an initial dose of 5 mg daily; increase by 5 mg every 1-2 weeks to a maximum dose of 20 mg daily, could be helpful with less side effects than cholinesterase inhibitors. Also, it was advisable to consider discontinuing medications which might impair cognition, such as, anticholinergics and amantadine.
References
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