The relationship between plasma phosphorylated α-synuclein and cognitive impairment in patients with Parkinson disease / 中华行为医学与脑科学杂志

ABSTRACT

Objective:To investigate the relationship between plasma phosphorylated α-synuclein (ps129-α-syn) and cognitive function in Parkinson disease (PD).Methods:This study recruited 90 PD patients who were hospitalized in the Department of Neurology, Henan province people's hospital from March 2019 to June 2020.Forty healthy middle-aged and elderly people with normal cognitive function who came to the hospital for physical examination were selected during the same period.Clinical characteristics and blood samples were collected.Patients with PD were classified into those with normally cognitive (PD-NC), mild cognitive impairment (PD-MCI), and dementia (PDD). The enzyme-linked immunosorbent assay was used to measure the plasma ps129-α-syn.Correlations between plasma ps129-α-syn and clinical characteristics such as disease duration, Hoehn-Yahr stage (H-Y), unified Parkinson's disease rating scale (UPDRS), Montreal cognitive assessment (MoCA), 14-item Hamilton anxiety rating scale (HAMA-14), the 24-item Hamilton depression rating scale (HAMD-24), levodopa equivalent daily dosage (LEDD), the scale of outcomes in Parkinson's disease for autonomic symptoms, SCOPA-AUT) were analyzed using Pearson or Spearman correlation analysis.Multiple linear regression analysis was used to evaluate the factors affecting the cognitive function of PD.Results:Plasma ps129-α-syn in PD patients was higher than that in healthy controls((19.44±8.93)μg/L, (10.78±5.87)μg/L, ( t=5.615, P<0.01). Plasma ps129-α-syn was higher in PD-MCI group((19.64±7.77)μg/L)and PDD group((23.79±9.47)μg/L) compared with that in PD-NC group((13.37±5.40)μg/L)( P<0.05). Plasma ps129-α-syn was positively correlated with H-Y ( r=0.404, P<0.01), UPDRS-Ⅲ( r=0.275, P=0.009), UPDRS-total ( r=0.211, P=0.046) and SCOPA-AUT( r=0.335, P=0.001). Plasma ps129-α-syn was negatively associated with MoCA ( r=-0.459, P<0.01). Multiple linear regression analysis suggested disease duration ( t=-4.618, P<0.01), ps129-α-syn( t=-3.792, P<0.01) and UPDRS-total ( t=-2.826, P=0.006) were independently associated with cognitive function.Plasma ps129-α-syn could discriminate between PD-NC and PD cognitive function impairment with an AUC of 0.7797 (95% CI 0.686 3-0.873 2, P<0.01). Conclusions:Plasma ps129-α-syn is correlated with cognitive function and the severity of motor symptoms in PD patients, and have high sensitivity and specificity in diagnosing PD cognitive dysfunction.Therefore, plasma ps129-α-syn can serve as a biomarker to assess cognitive function in PD.