Brit Mollenhauer, MD, University Medical Center Göttingen, Göttingen, Germany, discusses a longitudinal analysis of multiple neurotransmitter metabolites in cerebrospinal fluid (CSF) in early Parkinson’s disease (PD). Results showed that baseline levels of homovanillic acid (HVA) and 3,4-dihydroxyphenylacetic acid (DOPAC) were lower in individuals with PD compared with healthy controls. However, Dr Mollenhauer explains that initially, they expected a more marked decrease in the PD subjects. Although the method used in the study needs to be validated in a larger cohort, it could be an interesting addition to other biomarkers. This interview took place during the XXV World Congress of Neurology.