To explore the levels of cystatin C (CysC) and homocysteine (Hcy) in patients with Parkinson's disease (PD) and their evaluation value for the development of white matter lesions in PD patients.

One hundred and twenty-four PD patients admitted to Neurology Department of the Affiliated Ethnic Hospital of Guangxi Medical University from December 2020 to December 2021 were selected and divided into early PD group (61 cases) and mid to late PD group (63 cases) according to the period of PD symptoms. One hundred and fifteen healthy volunteers who underwent physical examinations in the hospital during the same period were included as the control group. Brain MRI was used to examine whether PD patients were associated with white matter lesions, and the patients were divided into concomitant group and non concomitant group. The serum CysC and Hcy levels in early PD group, mid to late stage PD group, control group, concomitant group, and non concomitant group were compared. The relationship between serum CysC and Hcy levels and associated white matter lesions in PD patients were analyzed using logistic multiple regression, and the value of both two for associated cerebral white matter lesions was analyzed using receiver operating characteristic curves.

The serum CysC and Hcy levels in the early PD group and the middle to late PD group were higher than those in the control group, and the middle to late PD group was higher than that in the early PD group, with statistical significance (P<0.05). Among 124 PD patients, 35 patients had white matter lesions (the concomitant group), the incidence rate was 28.23%, and the rest were non concomitant group (89 cases). The serum levels of CysC and Hcy in the concomitant group were significantly higher than those in the non concomitant group, with statistical significance (P<0.05). Age, course of PD, hypertension, diabetes, serum CysC and Hcy were all independent influencing factors for PD accompanied with white matter lesions (P<0.05). The cut-off values of assessing serum CysC and Hcy levels in patients with concomitant white matter lesions were 1.25 mg/L and 21.02 μmol/L, respectively. The sensitivity and AUC of PD for white matter lesions were higher in the combination evaluation than in the single indicator evaluation, and the difference was statistically significant (P<0.05).

Abnormal changes in serum CysC and Hcy levels can be used as important reference indicators for the clinical assessment of the risk of developing white matter lesions in PD patients, especially when combined, the evaluation value of the two is higher.