We appreciate the comments by Dr Panza and colleagues regarding our article demonstrating a relation between hypertension and an increased risk of all-cause MCI and NAMCI but not AMCI.1 Several studies have shown associations of dementia and cognitive decline with several vascular risk factors, including hypertension. Hypertension is a risk factor for cerebrovascular disease and vascular dementia, but it is unclear what role it has in AD, which is characterized by the deposition of β-amyloid.2 It is possible that hypertension causes cognitive impairment through cerebrovascular disease or white matter hyperintensities. Alternatively, hypertension may contribute to a blood-brain barrier dysfunction, which has been suggested to be involved in the etiology of dementia, or through shared risk factors, such as the formation of oxygen free radicals.
Reitz C, Mayeux R, Luchsinger JA. Antihypertensive Medications Influence the Rate of Conversion From Mild Cognitive Impairment to Alzheimer Disease—Reply. Arch Neurol. 2008;65(7):992-996. doi:10.1001/archneur.65.7.nlt0708