Despite mounting of evidence suggest that increased CRP concentration may have a deleterious impact on cognitive function and future risk of AD on non-demented populations (Teunissen et al., 2003; Engelhart et al., 2004; Komulainen et al., 2007; Kravitz et al., 2009; Wersching et al., 2010), conflicting findings have been reported in patients diagnosed with AD dementia and patients with mild cognitive impairment (MCI) (Locascio et al., 2008; O’Bryant et al., 2010; Silverman et al., 2012; Fernandes et al., 2020; Lewis and Knight, 2021). This evidence concerns the gene CRP and Alzheimer disease.