A study published in Neurology examined the association between skin nerve fiber density, cognitive performance, and regional brain structure in people with Parkinson’s disease (PD).
Researchers evaluated 155 people with PD and 50 healthy controls using skin biopsies, cognitive assessments, and brain MRI. Among participants with PD, reduced intraepidermal nerve fiber density (IENFD) was observed across all three cognitive groups: those with normal cognition, mild cognitive impairment, and Parkinson’s disease dementia.
Lower IENFD was also associated with poorer performance on global and domain-specific cognitive assessments, as well as lower gray matter volume in certain frontal and insular brain regions.
These findings contribute to research exploring associations between peripheral nerve changes and cognitive impairment in PD. Further longitudinal and multicenter research is needed to clarify these relationships and determine their potential clinical significance.
Source: Liu M, et al. Association of Skin Denervation With Brain Atrophy and Cognitive Impairment in Patients With Parkinson Disease. Neurology. 2026;107.
