Key Difference – Parkinson’s vs Huntington’s Disease
The key difference between Parkinson’s and Huntington’s disease is that Parkinson disease (PD) is a disorder with rigidity, tremors, slowing of movements, postural instability and gait disturbances usually occurring in old age due to degeneration of the substantia nigra of the midbrain while Huntington’s disease (HD) is a familial neurodegenerative disorder usually occurring in a younger population, characterized by emotional problems, loss of thinking ability (cognition) and abnormal choreiform movements (repetitive and rapid, jerky, involuntary movements).
What is Parkinson’s Disease?
Parkinson’s disease is a degenerative disorder of the central nervous system mainly affecting the motor system. The motor symptoms of Parkinson’s disease result from the degeneration of dopamine generating cells in the substantia nigra in the midbrain. The causes of this cell death are poorly understood. Early in the course of the disease, the most obvious symptoms are shaking, rigidity, slowness of movement and difficulty in walking and gait. Later, thinking and behavioral problems arise, with dementia commonly occurring in the advanced stages of the disease. Depression is the most common psychiatric symptom. Other symptoms include sensory, sleep problems and emotionally related problems.
Parkinson’s disease is more common in older people, and most cases occur after the age of 50; when it is seen in young, it is called young onset Parkinson’s disease. Diagnosis is by medical history and physical examination. There is no cure for PD, but medications, surgery, and multidisciplinary management can provide relief from the disabling symptoms. The main classes of drugs useful for treating motor symptoms are levodopa, dopamine agonists, and MAO-B inhibitors. These drugs too can cause disabling side effects. Deep brain stimulation has been tried as a treatment modality with some success.
What is Huntington’s Disease?
Huntington disease usually appears in a person’s thirties or forties. Early signs and symptoms can include depression, irritability, poor coordination, small involuntary movements, and trouble learning new information or making decisions. Many people with Huntington disease develop involuntary, repetitive jerking movements known as chorea. As the disease, progresses symptoms become more pronounced. People with this disorder also experience changes in personality and decrease in thinking abilities. Affected individuals usually live about 15 to 20 years after signs and symptoms begin.
There is no care for this disorder, and it is largely determined genetically due to mutations in the HTT gene. The juvenile form of this disorder also exists. Chorea can be controlled with medicines. However, other higher function abnormalities are difficult to control.
Coronal section from an MR brain scan of a patient with HD.
What is the difference between Parkinson’s and Huntington’s Disease?
Cause, Signs and Symptoms, Treatment and Management, Age of Onset of Parkinson’s and Huntington’s Disease:
Cause:
Parkinson’s Disease: PD is caused by the degeneration of the neurons in Substantia nigra of the midbrain.
Huntington’s Disease: HD is caused by the mutations in the HTT gene.
Age of Onset:
Parkinson’s Disease: PD usually occurs after the age of 50.
Huntington’s Disease: HD usually occurs in the thirties or forties.
Symptoms:
Parkinson’s Disease: PD causes tremors, rigidity, slowing of movements and gait disturbances.
Huntington’s Disease: HD causes higher function abnormalities such as problems in thinking and reasoning together with characteristic chorea.
Treatment:
Parkinson’s Disease: PD is treated with dopamine-enhancing drugs such as levodopa, dopamine agonists, etc.
Huntington’s Disease: HD has no curative treatment and main the treatment is supportive.
Life expediency:
Parkinson’s Disease: PD doesn’t have an effect on life expectancy. However, it reduces the quality of life.
Huntington’s Disease: HD patients live 15-20 years after the appearance of the first symptom.
Image Courtesy: Blausen.com staff. “Blausen gallery 2014”. Wikiversity Journal of Medicine. DOI:10.15347/wjm/2014.010. ISSN 20018762. – Own work. (CC BY 3.0) via Wikimedia Commons “Huntington” by Frank Gaillard – Own work. (CC BY-SA 3.0) via CommonsncG1vNJzZmivp6x7pbXFn5yrnZ6YsqOx07CcnqZemLyue8OinZ%2Bdopq7pLGMm5ytr5Wau268wKuioqajpLu0ecCnm2auo2K1trrToqWgrJ%2BjwG6wyKycmquVZA%3D%3D