In 2015, 160,000 Parkinson’s patients were treated in France, with approximately 25,000 new cases per year. The number of cases is increasing due to the aging of the population and the improvement in life expectancy. As the evolution of Parkinson’s disease is slow and its development insidious, the diagnosis is sometimes long.
According to research published in the journal The Lancet Neurology, a technique that identifies the buildup of abnormal protein deposits linked to Parkinson’s disease could aid in early detection. “The results of the study confirm that the technique – known as the α-synuclein seed amplification test (αSyn-SAA) – can accurately detect people with the neurodegenerative disease and suggest that it can identify those at risk and those with early non-motor symptoms prior to diagnosis,” the study release details. In effect, the presence of α-synuclein protein aggregates misfolded in the brain is a specific sign of this disease.
“Recognizing the heterogeneity of underlying pathology in patients with Parkinson’s disease has been a major challenge. An effective biomarker for Parkinson’s disease pathology could have profound implications for how we treat the disease, potentially allowing to diagnose people earlierto identify the best treatments for different subsets of patients and to accelerate clinical trials,” says co-lead author Professor Andrew Siderowf, researcher at the Parkinson’s Disease Progression Markers Initiative. (PPMI).
A “biological diagnosis”
“Our results suggest that the αSyn-SAA technique is very accurate in detecting disease biomarker Parkinson’s disease regardless of clinical features, allowing accurate diagnosis of the disease in patients at an early stage. Moreover, our results indicate that misfolded α-synuclein is detectable before dopaminergic damage in the brain is about to be observed by imaging, suggesting ubiquitous spread of these misfolded proteins before significant neuronal damage does not occur”, adds the co-lead author of the study, Luis Concha, director of research and development at Amprion (USA). As the study specifies, the results are uneven, particularly among carriers of the genetic mutation – known as LRRK2 – associated with certain forms of Parkinson’s.
In a comment related to this study, Professors Daniela Berg and Christine Klein, of the University Hospital of Schleswig-Holstein underlined the importance of this finding “which lays the foundation for a biological diagnosis of Parkinson’s disease”. Finally, the researchers were also interested in the loss of smell, a common symptom of patients. According to the study’s figures, among all participants with Parkinson’s disease who had a loss of smell, 97% had a positive αSyn-SAA, compared to 63% of those whose sense of smell was unchanged.