REN and Cognitive impairment: More importantly, according to the theory of the brain-heart axis (Manea et al., 2015; Riching et al., 2020), cognitive impairment is a manifestation of encephalopathy, which leads to abnormal cardiac structure and function via activation of the renin-angiotensin system (Nakagawa and Sigmund, 2017; Miller and Arnold, 2019), dysfunction of autonomic nervous system (Dorrance and Fink, 2015; Miller and Arnold, 2019), increased psychosocial stress and affective disorder (Rosengren et al., 2004; Kales et al., 2005; Monastero et al., 2009).