Diabetes and neuroaxonal damage in Parkinson’s disease

Patient’s with Parkinson’s disease (PD) with coexistent type 2 diabetes (T2DM) can manifest with more severe motor and cognitive phenotypes. The precise reasons for this remain unclear though underlying pathophysiological differences are increasingly implicated. More severe neuroaxonal injury in PD patients with T2DM was recently proposed as a potential mechanism for this. We explored this in the tracking Parkinson’s study and confirmed these findings. Cases with T2DM had higher serum neurofilament light levels and this remained significant after correction for age and vascular risk factor burden. Disentangling the underlying mechanism for more rapid axonal damage will be important in the development of disease modifying therapies for PD.