Muñoz-Delgado L, Macías-García D, Jesús S, et al. - Via this case–control analysis comprising 377 Parkinson disease (PD) patients and 355 healthy controls (HCs), researchers sought to ascertain if a different peripheral immune profile and neutrophil-to-lymphocyte ratio (NLR) were present in PD patients. They recorded leukocytes, subpopulations, and the NLR. PD patients exhibited significantly higher NLR vs HCs. No link was identified between NLR and age at onset, disease severity, or disease duration. In meta-analysis, NLR was likely to be higher in PD patients. Overall, it was evident that an altered peripheral immune profile as well as a higher NLR were present in PD patients vs HCs.