Brook Huxford: Parkinson’s disease and type 2 diabetes severity: a case-control biomarker study

Early career researchers share the focus of their research in these presentations from our Spring Research Update Meeting 2024.
Full abstract:
Background and Objectives: Type 2 diabetes (T2D) is a risk factor for Parkinson’s disease (PD) and PD severity, with inflammation and glycaemic control as potential drivers of this relationship. This cross-sectional biomarker study investigated whether T2D is associated with a more severe phenotype of PD, measured through blood- based markers of neuroaxonal damage, inflammation, and glycaemic control.
Methods: Patients with PD both with and without T2D, and healthy controls (HCs) were recruited from the East London Parkinson’s Disease (ELPD) project. Participants underwent blood sampling, and a full clinical assessment. Blood samples were analysed for plasma levels of neurofilament light chain (NfL), pro-inflammatory cytokines (IFN-γ, IL-6, L-1β and TNF-α), and C-Reactive Protein. DBS samples were used for analysis of glycated haemoglobin (HbA1c). The Movement Disorders Society (MDS) Unified Parkinson’s disease rating scale (UPDRS) Part 3 was used as a measure of motor symptom severity, and the Montreal Cognitive Assessment (MoCA) was used as a measure of cognitive symptom severity.
Results and conclusions: These data report higher levels of inflammation and neuroaxonal damage in patients with PD and T2D compared to PD without T2D, adding further evidence to the role of inflammation in the overlap between PD and T2D. Regression analyses have highlighted the strengthened link between plasma NfL and clinical symptom severity in patients with both PD and T2D, compared to PD without T2D. Future studies should assess longitudinal changes in markers of inflammation, neuroaxonal damage, and glycaemic control in patients with both PD and T2D.