Background: The influence of peripheral inflammation on nonmotor symptoms (NMSs) in Parkinson's disease (PD) remains unclear.
Objective: The aim of this study was to explore whether serum inflammatory marker profiles are associated with the progression of NMSs in early PD.
Methods: We included 45 patients with early PD and 20 healthy control subjects. Six inflammatory markers, including interleukin (IL)-1β, IL-2, IL-6, IL-10, tumor necrosis factor-α, and high-sensitivity C-reactive protein, were measured. NMSs were assessed using the Non-Motor Symptoms Scale, Montreal Cognitive Assessment, and Composite Autonomic Symptom Score-31 at baseline and after 3 years.
Results: Principal component (PC) analysis showed that only PC3 scores, mainly loaded by IL-2 and IL-6, were significantly elevated in the PD group compared with the control group. Higher PC3 scores in the PD group were associated with faster progression of Non-Motor Symptoms Scale total and mood/apathy domain scores. There were no significant associations of PC scores with Montreal Cognitive Assessment and Composite Autonomic Symptom Score-31 score changes.
Conclusions: Peripheral inflammation may be related to the evolution of NMSs, particularly mood symptoms, in the early stages of PD. © 2022 International Parkinson and Movement Disorder Society.
Keywords: Parkinson's disease; cytokine; interleukin; nonmotor symptoms; peripheral inflammation.
© 2022 International Parkinson and Movement Disorder Society.