However, the results obtained from observational studies are controversial: some studies show a higher cognitive efficacy of new cholinesterase inhibitors in female AD patients, whereas other reports indicate that men are more responsive to anti-dementia therapy or that there is no significant sex difference (Haywood and Mukaetova-Ladinska, 2006; Gallucci et al., 2016; Canevelli et al., 2017). Here, BCHE is linked to Alzheimer disease.