In a new study conducted by Shannon Halloway and team it was seen that in a population-based sample, serum Neurofilament light (Nf-L) was linked to incident clinical Parkinson's disease (PD), parkinsonian symptoms, and physical functional decrease. The findings of this study were published in the journal of Neurology.
Blood biomarkers may help detect PD, parkinsonism, and poor Parkinson's disease related outcomes such as physical functioning early. Neurofilament light, a neuronal cytoplasmic protein, is a neurodegenerative biomarker that can be measured in biofluids. The goal of this study was to look at the relationship between serum Nf-L levels at the start of the study and clinically diagnosed Parkinson's disease, parkinsonian symptoms, and changes in physical functioning over the course of 16 years in a population-based sample of older persons.

The Chicago Health and Aging Project (CHAP), a longitudinal population-based research, provided all of the data for this experiment. Using a structured version of the United Parkinson's Disease Rating Scale, clinical examinations included measuring parkinsonian indicators in four domains: parkinsonian, bradykinesia, stiffness, gait, and tremors. PD was diagnosed by board-certified neurologists. Chair stands, tandem walks, and timed walks were used to test physical functioning. The proportion of Nf-L in blood was determined using an ultrasensitive immunoassay.
The key findings of this study were as follow:
1. In the study of 1,254 patients, 77 (6.1%) developed clinical PD, with parkinsonian symptoms averaging 9.5.
2. After controlling for demographics, the APOE-e4 allele, and global cognition, a 2-fold greater serum Nf-L concentration was related with incident clinical PD and global parkinsonian symptoms.
3. This relationship was substantial for at least five years prior to diagnosis.
4. Participants with serum Nf-L levels below 18.5 pg/mL at baseline had a higher odds ratio of clinical PD than those with levels between 18.5–25.4 pg/mL, 25.4–37.3 pg/mL, and above 37.3 pg/mL at all time intervals from the time of diagnosis to more than five years before diagnosis.
5. A greater serum Nf-L concentration was linked to a quicker rate of physical function decrease.
In conclusion, this study's findings show that Nf-L might be used as a biomarker for neurodegeneration, including Parkinson's disease outcomes.
Reference:
Halloway, S., Desai, P., Beck, T., Aggarwal, N., Agarwal, P., Evans, D., & Rajan, K. (2022). Association of Neurofilament Light With the Development and Severity of Parkinson Disease. In Neurology (p. 10.1212/WNL.0000000000200338). Ovid Technologies (Wolters Kluwer Health). https://doi.org/10.1212/wnl.0000000000200338