Parkinson's disease dementia (PDD) is

dementia Dementia is a disorder which manifests as a set of related symptoms, which usually surfaces when the brain is damaged by injury or disease. The symptoms involve progressive impairments in memory, thinking, and behavior, which negatively affe ...

that is associated with

Parkinson's disease Parkinson's disease (PD), or simply Parkinson's, is a long-term degenerative disorder of the central nervous system that mainly affects the motor system. The symptoms usually emerge slowly, and as the disease worsens, non-motor symptoms becom ...

(PD). Together with

dementia with Lewy bodies Dementia with Lewy bodies (DLB) is a type of dementia characterized by changes in sleep, behavior, cognition, movement, and regulation of automatic bodily functions. Memory loss is not always an early symptom. The disease worsens over time ...

(DLB), it is one of the

Lewy body dementias Lewy body dementias are two similar and common subtypes of dementia—dementia with Lewy bodies (DLB) and Parkinson's disease dementia (PDD). Both are characterized by changes in thinking, movement, behavior, and mood. The two conditions have sim ...

characterized by abnormal deposits of

Lewy bodies Lewy bodies are the inclusion bodies – abnormal aggregations of protein – that develop inside nerve cells affected by Parkinson's disease (PD), the Lewy body dementias ( Parkinson's disease dementia and dementia with Lewy bodies (DLB)), and ...

in the brain. Parkinson's disease starts as a

movement disorder Movement disorder refers to any clinical syndrome with either an excess of movement or a paucity of voluntary and involuntary movements, unrelated to weakness or spasticity. Movement disorders are synonymous with basal ganglia or extrapyramidal d ...

, but progresses in most cases to include dementia, and changes in mood and behavior. The signs, symptoms and cognitive profile of PDD are similar to those of DLB; DLB and PDD are clinically similar after dementia occurs in Parkinson's disease. Parkinson's disease is a risk factor for PDD; it speeds up decline in cognition leading to PDD. Up to 78% of people with PD have dementia. Delusions in PDD are less common than in DLB, and persons with PD are typically less caught up in their visual hallucinations than those with DLB. There is a higher incidence of tremor at rest in PD than in DLB, and signs of

parkinsonism Parkinsonism is a clinical syndrome characterized by tremor, bradykinesia (slowed movements), rigidity, and postural instability. These are the four motor symptoms found in Parkinson's disease (PD), after which it is named, dementia with Lewy bo ...

in PDD are less symmetrical than in DLB. Parkinson's disease dementia can only be definitively diagnosed after death with an autopsy of the brain. The 2017 ''Fourth Consensus Report'' established diagnostic criteria for PDD and DLB. The diagnostic criteria are the same for both conditions, except that PDD is distinguished from DLB by the time frame in which dementia symptoms appear relative to parkinsonian symptoms. DLB is diagnosed when cognitive symptoms begin before or at the same time as parkinsonism. Parkinson's disease dementia is the diagnosis when Parkinson's disease is well established before the dementia occurs; that is, the onset of dementia is more than a year after the onset of parkinsonian symptoms.

Cognitive behavioral therapy Cognitive behavioral therapy (CBT) is a psycho-social intervention that aims to reduce symptoms of various mental health conditions, primarily depression and anxiety disorders. CBT focuses on challenging and changing cognitive distortions (suc ...

can help Parkinson's patients with

parkinsonian Parkinsonism is a clinical syndrome characterized by tremor, bradykinesia (slowed movements), rigidity, and postural instability. These are the four motor symptoms found in Parkinson's disease (PD), after which it is named, dementia with Lewy bo ...

pain,

insomnia Insomnia, also known as sleeplessness, is a sleep disorder in which people have trouble sleeping. They may have difficulty falling asleep, or staying asleep as long as desired. Insomnia is typically followed by daytime sleepiness, low energy, ...

, depression,

anxiety Anxiety is an emotion which is characterized by an unpleasant state of inner turmoil and includes feelings of dread over anticipated events. Anxiety is different than fear in that the former is defined as the anticipation of a future threat wh ...

, and

impulse disorder Impulse-control disorder (ICD) is a class of psychiatric disorders characterized by impulsivity – failure to resist a temptation, an urge, or an impulse; or having the inability to not speak on a thought. Many psychiatric disorders feature impu ...

s, if those interventions are properly adapted to the motor, cognitive and executive dysfunctions seen in Parkinson's disease, including Parkinson's dementia.

Society and culture

General awareness about LBD lags well behind that of

Parkinson's Parkinson's disease (PD), or simply Parkinson's, is a long-term degenerative disorder of the central nervous system that mainly affects the motor system. The symptoms usually emerge slowly, and as the disease worsens, non-motor symptoms becom ...

and

Alzheimer's Alzheimer's disease (AD) is a neurodegenerative disease that usually starts slowly and progressively worsens. It is the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in remembering recent events. As t ...

diseases, even though LBD is the second most common dementia, after Alzheimer's.

References

External links

{{DEFAULTSORT:Parkinson's disease dementia Lewy body dementia