Role of plasma neurofilament protein light chain in diagnosing and differentiating PD and multisystem atrophy-Parkinson subtypes / 中华神经医学杂志

ABSTRACT

Objective:To investigate the role of plasma neurofilament light chain (NfL) in diagnosing and differentiating Parkinson's disease (PD) and multiple system atrophy-Parkinsonian subtype (MSA-P).Methods:Forty PD patients and 23 MSA-P patients admitted to Department of Neurology, Henan Provincial People's Hospital from June 2019 to December 2021 were recruited; 27 healthy subjects accepted physical examination during the same period were selected as controls. Ultrasensitive Simoa technology was used to measure the plasma NfL. Differences in clinical data and plasma NfL were compared among all subjects. Correlations of plasma NfL with clinical characteristics, such as disease course, Hoehn-Year (H-Y) staging, Unified Parkinson's Disease Rating Scale (UPDRS), Montreal Cognitive Assessment (MoCA), Scale for Outcomes in Parkinson's Disease for Autonomic Symptoms (SCOPA-AUT) and levodopa equivalent daily dosage (LEDD), were analyzed with Pearson correlations. Receiver operating characteristic (ROC) curve was used to analyze the value of plasma NfL in diagnosing and differentiating PD and MSA-P.Results:Compared with MSA-P group, PD group had significantly longer disease course and statistically lower scores of UPDRS-II and SCOPA-AUT ( P<0.05). The plasma NfL in MSA-P group, PD group and healthy control group was decreased successively ([37.69±10.47] pg/mL, [17.85±4.23] pg/mL, [12.86±3.14] pg/mL, respectively), with statistical differences ( P<0.05). In MSA-P patients, Pearson correlations showed positive correlation between plasma NfL and age ( r=0.442, P=0.035); and Partial correlations showed positive correlations between plasma NfL and scores of UPDRS-I and UPDRS-III ( P<0.05), and plasma NfL showed no significant correlation with H-Y staging, UPDRS-III, MoCA, LEDD or SCOPA-AUT scores ( P>0.05). In PD patients, Pearson correlations showed that plasma NfL was positively correlated with age ( r=0.342, P=0.031); partial correlations showed that plasma NfL was positively correlated with H-Y staging and UPDRS-III, and negatively correlated with MoCA scores ( P<0.05); plasma NfL showed no significant correlation with disease course, scores of UPDRS-I and UPDRS-II, LEDD, and SCOPA-AUT scores ( P>0.05). ROC curve showed that the area under the curve (AUC) of plasma NfL in diagnosing PD was 0.814 (95% CI 0.712-0.920, P<0.001); AUC of plasma NfL in differentiating and diagnosing PD and MSA-P was 0.980 (95% CI 0.954-1.000, P<0.001); AUC of plasma NfL in diagnosing MSA-P was 0.998 (95% CI 0.993-1.000, P<0.001). Conclusions:Plasma NfL is correlated with severity of motor symptoms in MSA-P patients; plasma NfL is correlated with cognitive function and disease course in PD patients. Besides, plasma NfL has high sensitivity and specificity in differentiating PD and MSA-P, therefore, plasma NfL could serve as a biomarker to diagnosis and differentiate PD.