Effects of angiotensin II receptor blockers on dementia.

The renin-angiotensin system (RAS) is involved in pathological mechanisms of target organ damage as well as the induction of hypertension; therefore, blockade of the RAS has been expected to prevent cardiovascular and cerebrovascular diseases beyond its antihypertensive effects. In spite of the well-characterized role of angiotensin (Ang) II receptor blockers (ARBs) in preventing the onset and recurrence of stroke, the clinical evidence for an effect of ARBs on dementia has not been definitive. However, preliminary experiments raise the possibility that treatment using ARBs may prevent ischemic brain damage and cognitive impairment. Moreover, recent reports have shown that some ARBs prevent amyloid beta deposition in the brain and attenuate cognitive impairment in Alzheimer disease models. Furthermore, recent cohort studies indicate that lower incidence of Alzheimer disease is observed in elderly individuals treated with ARBs. These results indicate a beneficial role for ARBs in cognitive impairment associated with vascular disease, Alzheimer disease, metabolic syndrome and other neurodegenerative diseases. Here, we review the effects of ARBs on the brain with a focus on dementia and future therapeutic approaches for elderly people suffering from disabilities.