Post by Admin on Jul 25, 2023 0:11:11 GMT
Parkinson's disease
en.wikipedia.org/wiki/Parkinson%27s_disease
Parkinson's disease (PD), or simply Parkinson's,[12] is a chronic 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 become more common.[3][7] Early symptoms are tremor, rigidity, slowness of movement, and difficulty with walking.[3] Problems may also arise with cognition, behaviour, sleep, and sensory systems.[3][13][4] Parkinson's disease dementia becomes common in advanced stages of the disease.
The motor symptoms of the disease result from the death of nerve cells in the substantia nigra, a region of the midbrain that supplies dopamine to the basal ganglia.[3] The cause of this cell death is poorly understood, but involves the aggregation of the protein alpha-synuclein into Lewy bodies within the neurons.[14][7] Collectively, the main motor symptoms are known as parkinsonism or a parkinsonian syndrome.[7]
The cause of PD is unknown, but a combination of genetic and environmental factors are believed to play a role.[7] Those with an affected family member are at an increased risk of getting the disease, with certain genes known to be inheritable risk factors.[15] Environmental risks include exposure to pesticides, and prior head injuries;[7] a history of exposure to trichloroethylene is also suspected.[16] Conversely, caffeine and nicotine appear to be protective.[17][7][18]
Diagnosis is mainly based on symptoms, with motor symptoms being the most frequently presented. Tests such as neuroimaging (magnetic resonance imaging or imaging to look at dopamine neuronal dysfunction known as DaT scan) are used to help rule out other diseases.[19][3] Parkinson's disease typically occurs in people over the age of 60, of whom about one percent are affected.[3][6] Males are affected at a ratio of around 3:2 compared with females.[7] When it is seen in people before the age of 50, it is called early-onset PD.[20] By 2015, PD affected 6.2 million people and resulted in about 117,400 deaths globally.[10][11] The number of people with PD older than fifty is expected to double by 2030.[21] The average life expectancy following diagnosis is 7–15 years.[4]
No cure for PD is known; treatment aims to reduce the effects of the symptoms.[3][22] Initial treatment is typically with the medications levodopa (L-DOPA), MAO-B inhibitors, or dopamine agonists.[19] As the disease progresses, these medications become less effective, while at the same time producing a side effect marked by involuntary muscle movements.[4] At that time, medications may be used in combination and doses may be increased.[19] Diet and certain forms of rehabilitation have shown some effectiveness at improving symptoms.[23][24] Surgery to place microelectrodes for deep brain stimulation has been used to reduce severe motor symptoms where drugs are ineffective.[3] Evidence for treatments for the nonmovement-related symptoms of PD, such as sleep disturbances and emotional problems, is less strong.[7]
The disease is named after English doctor James Parkinson, who published the first detailed description in An Essay on the Shaking Palsy, in 1817.[25][26] Public awareness campaigns include World Parkinson's Day (on 11 April, the birthday of James Parkinson) and the use of a red tulip as the symbol of the disease.[27] People with PD who have increased the public's awareness of the condition include boxer Muhammad Ali, comedian Billy Connolly, actor Michael J. Fox, Olympic cyclist Davis Phinney, and actor Alan Alda.[28][29][30][31]
Classification
Parkinson's disease is the commonest form of parkinsonism and is also called idiopathic parkinsonism, meaning that it has no identifiable cause.[22][32] The accumulation of a misfolded protein alpha-synuclein in the brain, and its spread throughout the brain makes Parkinson's disease a neurodegenerative disease classed as a synucleinopathy, and more specifically as an alpha-synucleinopathy (αsynucleinopathy).[33]
Other Parkinson-plus syndromes can have similar movement symptoms but have a variety of associated symptoms. Some of these are also synucleinopathies. Lewy body dementia involves motor symptoms with early onset of cognitive dysfunction and hallucinations which precede motor symptoms. Alternatively, multiple systems atrophy or MSA usually has early onset of autonomic dysfunction (such as orthostasis), and may have autonomic predominance, cerebellar symptom predominance, or Parkinsonian predominance.[34]
Other Parkinson-plus syndromes involve tau, rather than alpha-synuclein. These include progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS). PSP predominantly involves rigidity, early falls, bulbar symptoms, and vertical gaze restriction; it can be associated with frontotemporal dementia symptoms. CBS involves asymmetric parkinsonism, dystonia, alien limb, and myoclonic jerking.[35] These presentation timelines and associated symptoms can help differentiate these similar movement disorders from idiopathic Parkinson disease.
en.wikipedia.org/wiki/Parkinson%27s_disease
Parkinson's disease (PD), or simply Parkinson's,[12] is a chronic 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 become more common.[3][7] Early symptoms are tremor, rigidity, slowness of movement, and difficulty with walking.[3] Problems may also arise with cognition, behaviour, sleep, and sensory systems.[3][13][4] Parkinson's disease dementia becomes common in advanced stages of the disease.
The motor symptoms of the disease result from the death of nerve cells in the substantia nigra, a region of the midbrain that supplies dopamine to the basal ganglia.[3] The cause of this cell death is poorly understood, but involves the aggregation of the protein alpha-synuclein into Lewy bodies within the neurons.[14][7] Collectively, the main motor symptoms are known as parkinsonism or a parkinsonian syndrome.[7]
The cause of PD is unknown, but a combination of genetic and environmental factors are believed to play a role.[7] Those with an affected family member are at an increased risk of getting the disease, with certain genes known to be inheritable risk factors.[15] Environmental risks include exposure to pesticides, and prior head injuries;[7] a history of exposure to trichloroethylene is also suspected.[16] Conversely, caffeine and nicotine appear to be protective.[17][7][18]
Diagnosis is mainly based on symptoms, with motor symptoms being the most frequently presented. Tests such as neuroimaging (magnetic resonance imaging or imaging to look at dopamine neuronal dysfunction known as DaT scan) are used to help rule out other diseases.[19][3] Parkinson's disease typically occurs in people over the age of 60, of whom about one percent are affected.[3][6] Males are affected at a ratio of around 3:2 compared with females.[7] When it is seen in people before the age of 50, it is called early-onset PD.[20] By 2015, PD affected 6.2 million people and resulted in about 117,400 deaths globally.[10][11] The number of people with PD older than fifty is expected to double by 2030.[21] The average life expectancy following diagnosis is 7–15 years.[4]
No cure for PD is known; treatment aims to reduce the effects of the symptoms.[3][22] Initial treatment is typically with the medications levodopa (L-DOPA), MAO-B inhibitors, or dopamine agonists.[19] As the disease progresses, these medications become less effective, while at the same time producing a side effect marked by involuntary muscle movements.[4] At that time, medications may be used in combination and doses may be increased.[19] Diet and certain forms of rehabilitation have shown some effectiveness at improving symptoms.[23][24] Surgery to place microelectrodes for deep brain stimulation has been used to reduce severe motor symptoms where drugs are ineffective.[3] Evidence for treatments for the nonmovement-related symptoms of PD, such as sleep disturbances and emotional problems, is less strong.[7]
The disease is named after English doctor James Parkinson, who published the first detailed description in An Essay on the Shaking Palsy, in 1817.[25][26] Public awareness campaigns include World Parkinson's Day (on 11 April, the birthday of James Parkinson) and the use of a red tulip as the symbol of the disease.[27] People with PD who have increased the public's awareness of the condition include boxer Muhammad Ali, comedian Billy Connolly, actor Michael J. Fox, Olympic cyclist Davis Phinney, and actor Alan Alda.[28][29][30][31]
Classification
Parkinson's disease is the commonest form of parkinsonism and is also called idiopathic parkinsonism, meaning that it has no identifiable cause.[22][32] The accumulation of a misfolded protein alpha-synuclein in the brain, and its spread throughout the brain makes Parkinson's disease a neurodegenerative disease classed as a synucleinopathy, and more specifically as an alpha-synucleinopathy (αsynucleinopathy).[33]
Other Parkinson-plus syndromes can have similar movement symptoms but have a variety of associated symptoms. Some of these are also synucleinopathies. Lewy body dementia involves motor symptoms with early onset of cognitive dysfunction and hallucinations which precede motor symptoms. Alternatively, multiple systems atrophy or MSA usually has early onset of autonomic dysfunction (such as orthostasis), and may have autonomic predominance, cerebellar symptom predominance, or Parkinsonian predominance.[34]
Other Parkinson-plus syndromes involve tau, rather than alpha-synuclein. These include progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS). PSP predominantly involves rigidity, early falls, bulbar symptoms, and vertical gaze restriction; it can be associated with frontotemporal dementia symptoms. CBS involves asymmetric parkinsonism, dystonia, alien limb, and myoclonic jerking.[35] These presentation timelines and associated symptoms can help differentiate these similar movement disorders from idiopathic Parkinson disease.