Serum Growth Differentiation Factor 15 in Parkinson Disease.

BACKGROUND: Growth differentiation factor 15 (GDF15) has been shown to be protective for dopaminergic neurons in animal and ex vivo experiments. However, little is known about its effect on the human body.

OBJECTIVE: This study investigated associations between serum GDF15 levels and clinical parameters in patients with Parkinson disease (PD).

METHODS: Idiopathic PD patients (n = 104) and age-matched controls (n = 88) were enrolled. Serum GDF15 levels were measured by human enzyme-linked immunosorbent assay. Univariate and multivariate analyses investigated correlations between GDF15 and clinical characteristics, including disease severity by the Unified PD Rating Scale (UPDRS)-III. The diagnostic value of GDF15 was evaluated by receiver-operating characteristic curve (ROC) analysis.

RESULTS: The serum GDF15 levels of the PD patients were significantly higher than those of the healthy controls. In PD patients, serum GDF15 levels in men were significantly higher than in women. GDF15 levels correlated with age, gender, disease duration, and UPDRS-III score. After adjusting for confounding factors, multiple linear regression analysis showed that the serum GDF15 level (β = 0.015, p = 0.001) was an independent risk factor for UPDRS-III score. In ROC analysis, GDF15 achieved an area under the curve of 0.86 for the identification of PD, with a sensitivity of 71.15% and a specificity of 87.50%.

CONCLUSION: GDF15 may be a potential biomarker for the diagnosis and monitoring of motor severity in PD.