Does blood pressure lowering treatment prevents dementia or cognitive decline in patients with cardiovascular and cerebrovascular disease?
There is increasing evidence that both hypertension and stroke play important roles in the development of cognitive decline and dementia. Despite five high-quality randomised controlled trials (RCTs) in this area to date, there remains uncertainty about the role of blood pressure lowering therapy in the prevention of cognitive decline and dementia. It appears that lack of definitive results from these trials can be explained on the basis of (a) insufficient power to detect modest treatment effects; (b) measurement error in the diagnosis of dementia; (c) variations in the treatment effects between different types of antihypertensive agents; and (d) bias due to missing data, variation in baseline factors such as levels of blood pressure, and the inclusion of patients with cognitive impairment at entry. Preliminary meta-analysis of RCTs supports the hypothesis that blood pressure lowering may prevent dementia in high-risk patients, that is those with vascular disease. However, a meta-analysis of individual patient data (IPD) from these, and other relevant trials in patients with vascular disease, would provide much more reliable data. If the hypothesis were confirmed, it would certainly be of considerable importance not only in terms of our understanding of the aetiology of dementia, but also in promoting blood pressure lowering strategies for broader public health good.
Feigin
Valery
V
Clinical Trials Research Unit, University of Auckland, Private Bag 92019, Auckland, New Zealand. v.feigin@ctru.auckland.ac.nz
Ratnasabapathy
Yogini
Y
Anderson
Craig
C
D000368:Aged; D000369:Aged, 80 and over; D000959:Antihypertensive Agents / Q000627:therapeutic use*; D002318:Cardiovascular Diseases / Q000188:drug therapy* / Q000523:psychology*; D002561:Cerebrovascular Disorders / Q000188:drug therapy* / Q000523:psychology*; D003072:Cognition Disorders / Q000517:prevention & control*; D015140:Dementia, Vascular / Q000517:prevention & control*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D016032:Randomized Controlled Trials as Topic; D006113:United Kingdom
D000959:Antihypertensive Agents