APOE and Parkinson disease: However, the effects of ApoE gene polymorphisms upon brain morphology and cognitive function are not limited to AD patients; brain atrophy and cognition impairment associated with ApoE ε4 carriers were also found in studies of healthy elderly subjects (Honea et al., 2009; Crivello et al., 2010; Lu et al., 2011) and in non-AD patients with neurological disorders, such as frontotemporal dementia (Boccardi et al., 2004; Agosta et al., 2009), Parkinson’s disease (Mata et al., 2014) and HIV infection (Wendelken et al., 2016).