Dementia in Parkinson's disease

General outline   
Parkinson' disease is known as a movement disorder. The movement disorder is due to dopaminergic neurons mainly in the substantia nigra. Motor symptoms always precede cognitive impairment by several years signs with an involvement of cognitive impairment due to a degeneration changes in cortical structures with generally presence of Lewy bodies.

Synonyms:    Shaking palsy

Symptoms    The key features of cognitive impairment including dementia in ParkD is slowing of thought, reduced attention, and impairment executive function (planning, organising, solving problems). Patient may become obsessional, sometimes loss of emotional control, sometimes outbursts of anger. Medications may cause or aggravate visual hallucinations.

Language problems (slower speech, not word finding difficulties)

Course:
  
Caregiver problems    With movement disorder, slowness in information processing (difficulty of communication) may lead to carer frustration.
Epidemiology    Parkinson's disease is not RARE, however, only 10-20 % of the patients develop cognitive impairment / dementia

Aetiology    Abnormal aggregation of alpha synuclein in Lewy bodies. It is more than Lewy bodies accumulation. There are inherited form of Parkinson's disease associated with mutation on chromosomes xxx.

Heredity    Families with familial PD (several chromosomes involved)

Diagnostic procedures    Nothing specific.

Treatment and rehabilitation    The movement disorder is treated by compounds augmenting dopamine transmission.

Medication may cause or aggravate hallucinations and  psychotic symptoms.

Ongoing research / Clinical trials    Trials have been conducted on small patient samples demonstrating benefits of Cholinesterase inhibitors on cognitive ability.

Available services    Parkinson's disease societies in several countries. They provide services for the movement disorders but have less information on the cognitive problems associated with the disorder.
If dementia refer to AD associations.

Further reading