Parkinson's Disease

If your doctor thinks you might have PD, they will ask questions about symptoms, examine a certain part of the brain, refer you to a specialist (like a neurologist and/or a geriatrician), run certain mental or physical tests.[9,11]

• Brain scans like CT, MRI, PET and DaTscan.[10,11,12,13,14]
   
  • A CT (computed tomography) scan is a type of imaging technique where X-rays are passed through the body from different angles to make pictures of the brain.[11,12] It helps to rule out other causes like vascular disease or tumours for Parkinson’s-like symptoms.[11]
   
  • An MRI (magnetic resonance imaging) scan is a type of imaging technique where a strong magnetic field and radio waves are used to produce detailed images of the inside of the brain.[11,13] It helps to distinguish Parkinson’s disease from other Parkinson’s-like conditions.[11]
   
  • A PET (positron emission tomography) scan is a type of imaging technique that detects the radiation given off by a substance injected beforehand.[14] PET is an imaging test that helps to show how aspects of your brain are working. It does so by helping to reveal the biochemical or metabolic function of your brain.
   
  • A DaTscan (Dopamine Transporter Scan) is a type of imaging technique where a small amount of radioactive material is injected into the blood, where it circulates around the body and makes its way to the brain, where it is captured with a camera as an image.[11] This image is used to identify the loss of dopamine-producing brain cells leading to Parkinson’s. It helps to distinguish Parkinson’s disease from other conditions with similar symptoms.[10,11]

• New imaging techniques are being developed and research is ongoing to detect Parkinson’s with new blood test, skin test and reliable smell test, heart scans (MIBG) [11,20]

Symptoms of PD usually begin with early symptoms and the disease is known as ‘early/initial’ at this stage. PD may get worse over time. This is also known as ‘progressive disease’, or ‘disease progression’. As PD progresses, the symptoms become more severe from mid-stage to advanced-stage.

In 1967, Hoehn and Yahr defined five stages of PD based on clinical instability. This helped to classify PD into the early-stage represented by stages 1 and 2, the mid-stage represented by stages 2 and 3 and the advanced stage, represented by stages 4 and 5.[15]

PD can be divided into three main stages:[15]

• Early-stage: Early-stage PD is the first stage of the disease, where the person shows mild symptoms which do not interfere with daily activities. The person is able to live independently, but daily tasks require time and become difficult.

• Mid-stage: In mid-stage PD, the person is functionally restricted in their daily activities but is physically capable of living an independent life. The disability is mild to moderate at this stage.

• Advanced-stage: Advanced-stage PD is the final stage of the disease, where symptoms are fully developed and debilitating, making the person bedridden or bound to a wheelchair. Around-the-clock care is required for all activities.

Some doctors use a more complex scale to make sure that not only physical symptoms but all aspects of the disease are included in staging.[16]

In rare cases, PD is caused by a change (known as 'mutation') in the genes that are passed on from parents. Some of the most common gene mutations a child can inherit from their parents are GBA, PRKN and PINK1.[17]

People who are carriers of PD will not develop PD but may show milder or early symptoms of a condition called parkinsonism which describes several Parkinson’s-like symptoms like tremors, muscle rigidity and slowness of movement.[17]

At the moment there is no cure for PD, so treatments are used to relieve symptoms in order to improve quality of life. The main treatments used for PD are:[1,3,18,19]

• Supportive therapies:
   
  • Physiotherapy can support people with PD to relieve muscle stiffness and joint pain through exercise and movements. This helps overall to improve the person’s fitness and ability to manage things independently.
   
  • Occupational therapy can identify the difficulties faced due to PD in everyday life and can work out practical solutions to ensure a safe and appropriate home setup and to maintain independence as long as possible. There is also growing use of smart home technology.
   
  • Speech and language therapists help the person with PD to solve problems by teaching how to speak and perform some swallowing exercises, or by some assistive therapy.
   
  • Dieticians can help with making dietary changes, which can improve some symptoms such as increasing fibrous food in the diet and drinking enough fluids to reduce constipation, increasing salt intake in the diet and eating small and frequent meals to avoid issues with low blood pressure, and making changes to the diet to avoid unintentional weight loss.
 
• Medications: Medications that are metabolised to or imitate the chemical dopamine, substances that initiate a physiological response when combined with a receptor (dopamine agonists), and medicines that block the breakdown of dopamine (monoamine oxidase-B inhibitors). Oral and injectable options are available.
 
• Surgery: Deep brain stimulation is a procedure, which involves surgically implanting a pulse generator in the brain (similar to a heart pacemaker in the chest wall). This is connected to one or two thin wires under the skin and is correctly inserted in specific areas in the brain. A tiny electric current produced by this generator stimulates the part of the brain that is affected by PD, which might ease some symptoms for some people.
 
• Focused ultrasound: It is an alternative to deep brain stimulation and offers a non-invasive surgical procedure for Parkinson’s motor symptoms or other movement disorders that are characterised by uncontrolled, involuntary movements (dyskinesia).
 
• Additional symptoms may need to be treated separately.

Clinical trials (which can also be called ‘research studies’) are designed to look at how safe experimental drugs or procedures (such as new types of surgery) are and how well they work. Researchers are working hard to learn more about PD by researching on how to slow or halt the breakdown/death of brain cells (neurodegeneration) by enhancing the clearance of abnormal proteins and blocking their communication, improving mitochondrial activity and targeting the inflammation of neurons.[19]

Furthermore, topics of research include immunotherapies, using established drugs for a new indication (drug repurposing), targeting a specific type of chemical messenger (neurotransmitter) system called non-dopaminergic neurotransmitter systems, components relating to the growth of nervous tissue called neurotrophic factors, regenerative treatments and advances in deep brain stimulation.[18,19]

As researchers learn more about PD, clinical trials will be set up to look at potential new treatments.

If you would like to know more about Roche sponsored clinical trials or are interested in taking part in a clinical trial, speak to your doctor or visit the Roche ForPatients clinical trials page.