Types of Parkinson's Disease

Parkinsons generally occurs between the ages of 50 and 65, however, if PD occurs before the age of 50 this is referred to as Young Onset Parkinson's Disease. Parkinson's Disease is commonly confused with Parkinsonism, which are disorders that mimic PD symptoms.

Young Onset Parkinson’s Disease (YOPD)

YOPD occurs in people under the age of 50. It affects between 10 and 20 percent of people with Parkinson’s disease. People who have several family members with Parkinson’s disease have an increased risk of YOPD. Head trauma may also be a risk factor. People with YOPD are more likely to experience symptoms of dystonia and dyskinesia (due to medication treatment using Levodopa). Dystonia causes involuntary contractions of the muscles that cause the affected body part to twist abnormally. Dyskinesia causes sudden, involuntary muscle spasms which result in jerking body movements or tics. People with YOPD tend to be less likely to experience symptoms such as problems with gait, balance, or dementia.

Types of Parkinsonism

Parkinson's disease should not be confused with Parkinsonism, also called Parkison’s syndrome,
Atypical Parkinsonism Disorder, or Parkinson’s Plus. Parkinsonism refers to a group of neurodegenerative disorders that produce motor problems similar to those caused by Parkinson’s Disease. These disorders include: 

• Drug-Induced Parkinsonism (DIP): After Parkinson’s disease, this is the most commonly diagnosed of the Parkinson-like neurodegenerative disorders in elderly people. Often patients with this condition may be misdiagnosed with Parkinson’s disease because the signs and symptoms are so similar. DIP is caused by dopamine agonists (medications which block the function of dopamine). These include some antipsychotic medications, dopamine depletors, SSRIs (serotonin reuptake inhibitors), and neuroleptics (a type of tranquiliser). Treatment for DIP usually involves identifying the offending medication and exchanging it for one which will not have the same effects on dopamine levels.
• Multiple System Atrophy (MSA): A rare neurodegenerative disease that is caused by damage and death of nerve cells in the spinal cord and brain. It affects the autonomic nervous system (which regulates normal homeostatic bodily functions including but not limited to heart rate, perspiration, urination, sexual arousal, and digestion) and motor functions. Symptoms include difficulty walking, problems with balance, and stiffened muscles, urinary incontinence, and erectile dysfunction, among other symptoms. The aim of treatment for MSA is to manage symptomatology.
• Progressive Supranuclear Palsy (PSP): A rare progressive disorder that affects many motor functions including swallowing, gait, vision, and speech as well as cognitive functions, mood, and behavior. It is caused by the death of nerve cells in the brain. There is no specific treatment for PSP, so the goal is to manage symptoms.
• Vascular Parkinsonism: This is caused by blood clots in the brain which are a result of several mini strokes. The condition mainly affects the lower body and causes difficulty walking. Unfortunately, treating vascular parkinsonism with the medications typically used to treat Parkinson’s disease is rarely effective. The goal of treatment is to reduce the risk of further strokes as much as possible. This can include living a healthy lifestyle (exercise/ healthy diet), using blood thinners, and stopping smoking. 
• Dementia with Lewy bodies (DLB): This condition is a form of progressive dementia and is the second most commonly diagnosed form of dementia after Alzheimer’s disease. It is caused by abnormal protein deposits in the brain that form into masses - these are called Lewy bodies after the German neurologist who discovered them. The reason Lewy bodies appear in the brain is not known, however, these deposits obstruct neurotransmissions, chemical balances, and eventually lead to nerve death. Symptoms may include problems with movement and cognitive functions. The aim of treatment is to manage symptoms with medication and therapy.
• Corticobasal Syndrome (CBS): This is the least common type of Parkinsonism. Symptoms include imparied cognitive functions (usually arising before motor issues) and impaired motor skills. There is no treatment to slow the advance of this condition and unfortunately, the symptoms do not typically respond well to therapy.
• Essential tremor (ET): The cause of this type of Parkinsonism is not known, although it is hereditary in around 50 percent of cases. ET is more apparent when a person is moving rather than when at rest and can affect gait and fine manual movements or tasks (such as using a pencil or utensil). Treatment usually involves medications such as tranquilizers, beta blockers (propranolol), anti-seizure drugs, and botulinum toxin injections (for muscle spasms). If the tremors are particularly debilitating, surgery may be an option. Surgical options include Gamma Knife thalamotomy, focused ultrasound thalamotomy, and deep brain stimulation.
• Normal pressure hydrocephalus (NSA): NSA is a disorder in which an excess of cerebrospinal fluid (CSF) causes enlargement of the ventricles in the brain. The symptomatology of NSA is similar to Vascular Parkinsonism and includes mild cognitive impairment, such as forgetfulness, difficulty walking, problems with balance, and loss of bladder control (as the condition progresses). Treatment involves the placement of a shunt in the brain to drain the excess CSF.