Renin-angiotensin-aldosterone System Inhibition In Patients Without Prior Cerebrovascular Disease For Prevention Of Cognitive Impairment

Background：Hypertension and cognitive impairment are prevalent in older people. It isknown that hypertension is a risk factor for dementia and recent studies havesuggested renin-angiotensin-aldosterone system impacts upon prevalence of dementia.The question is therefore whether treatment of renin-angiotensin-aldosterone systeminhibition lowers the rate of cognitive decline.Objectives：To assess the effects of renin-angiotensin-aldosterone system inhibition for theprevention of dementia and cognitive decline in patients with hypertension but nohistory of cerebrovascular disease.Search strategy：The trials were identified through a search of PubMed EMBASE CochraneCentral Register of Controlled Trials（Ovid）ALOIS on April2014.Selection criteria：Randomized, controlled trials in which renin-angiotensin-aldosterone systeminhibition were given only for at least six months.Data collection and analysis：Two independent reviewers assessed trial quality and extracted data. Thefollowing outcomes were assessed: cognitive change from baseline, incidence of sideeffectsMain results：Three trials including6383hypertensive subjects were identified. many ageabove70years. many control group treat as other antihypertensive, such as acalcium-channel blocker, a diuretic or β-Blocker. The combined result of the twotrials reporting change in Mini Mental State Examination (MMSE) did not indicate abenefit from treatment (Weighted Mean Difference (WMD)=0.11,0.11,95%CI-0.02,0.24) The combined result of the two trials reporting change in Trail Making Bdid not indicate a benefit from treatment (Weighted Mean Difference (WMD)= 2.11,95%CI1.44,2.47)..Two trials reported adverse effects the combining results indicated a significantbenefit from other antihypertensive (OR=0.53,95%CI0.29,0.95,OR=-0.27,95%CI-0.06,-1.18).Authors’conclusions：There was a few convincing evidence from the trials identified thatrenin-angiotensin-aldosterone system inhibition may prevents the development ofdementia or cognitive impairment in hypertensive patients with no apparent priorcerebrovascular disease.