APOE4 carriage confers an elevated hazard towards PDD (OR = 1.60—Sanghvi et al., 2020 [107]; OR = 1.72—Pang et al., 2018 [78]; OR = 1.74—Williams-Gray et al., 2009 [75]).Ethnic interactions may play a role: APOE4 may confer an elevated risk towards PD in Asian populations (OR = 1.88 Sun et al., 2019 [77]). Here, APOE is linked to Parkinson disease.