Using linear mixed-effects models with random intercepts for participants and fixed effects for group (PD vs. Control), visit, and their interaction, we analyzed repeated MoCA scores and CSF biomarkers from BL through V8 (MoCA: PD n = 703, controls n = 207; biomarkers: p-tau PD n = 487/controls n = 176; t-tau PD n = 487/controls n = 176; p-tau/Aβ42 PD n = 486/controls n = 176). The gene discussed is MAPT; the disease is Parkinson disease.