In Parkinson’s disease, nerve cells in the brain die over time, so early treatment is essential. A new test could enable early detection.
Parkinson’s syndrome is one of the most common neurological diseases. As a result, some neurons in the brain gradually die. This process affects the whole body, resulting in numerous symptoms such as trembling hands, poor coordination of movements, and muscle stiffness.
A new test could help detect the onset of Parkinson’s disease at an early stage, even before the brain is damaged. This is the result of a study conducted by the University of Pennsylvania, USA and published in the scientific journal “The Lancet Neurology”.
Early diagnosis has been problematic until now, because signs of the disease are often not obvious at first and sometimes go unnoticed by sufferers. So treatment is often only done at an advanced stage – when certain areas of the brain have already been damaged.
The protein is found in 88 percent of Parkinson’s patients
The main role in the new test is played by alpha-synuclein, a protein found in nerve cells. If the protein structure is damaged, it can clump together and form deposits in the midbrain. These deposits are also called Lewy bodies and are considered the main feature of Parkinson’s disease.
The test developed (Alpha-Synuclein Seed Amplification Test, αSyn-SAA for short) can detect the protein in patients’ brain fluid and thus has the potential to distinguish people with Parkinson’s disease from healthy people at an early stage.
In the study, the research team led by Professor Andrew Sideroff examined 1,123 people, including:
- Parkinson’s patients
- People with pre-existing conditions thought to be presenters of Parkinson’s disease (such as certain sleep disorders)
- People with genetic risk factors
- healthy people
The result: The test was able to detect abnormalities of alpha-synuclein in the cerebrospinal fluid in 88 percent of Parkinson’s patients. “Our results indicate that the αSyn-SAA method identifies biomarkers of Parkinson’s disease very reliably,” co-author Luis Concha-Marambio was quoted as saying in the Lancet letter.
The cause of the disease is decisive
However, depending on people’s genetics, test results vary. Genetic risk factors include GBA and LRRK2 genetic variants. They increase the risk of developing the disease, as do other factors such as age, certain chemicals, or brain injury.
The test was able to detect an alpha-synuclein abnormality in 96 percent of patients with the genetic risk factor GBA. In patients with the LRRK2 variant, the percentage was only 68 percent. The authors believe that the disease may be due to other mechanisms.
The incidence rate also varies among people with pre-existing illnesses that can later lead to Parkinson’s: If, for example, the sense of smell was impaired by a prior illness, the defective protein was detectable in a good 97 percent of the participants. For people with sleep disorders, it was only 63 percent.
The alpha-synuclein test makes very early indications possible
According to the authors, the test can be very helpful in early detection, despite sometimes patchy results. The reason: In most of the participants with pre-Parkinson’s disease, where the protein was present in the cerebrospinal fluid, there was no evidence of changes in neurons in the midbrain. So alpha-synuclein can be a very early indicator of developing disease.
The test is a ‘game changer’ for diagnosing Parkinson’s disease
The test also raises high hopes in the international research community. In a commentary, Daniela Berg and Christine Klein of the University Hospital Schleswig-Holstein describe the alpha-synuclein detection method as a “game-changer” for the diagnosis, research and treatment of Parkinson’s disease. The head of the German Society of Neurology (DGN), Lars Timmermann, is also optimistic and expects the results to have an impact on new treatments in the coming years.
