Vascular dementia and Alzheimer’s disease: Do they have similar aetiologies?
The article by Purandare and colleagues suggests particulate cerebral
embolisation is equally important in the pathogenesis of vascular dementia
and Alzheimer’s disease (AD) in the elderly . Platelets are the main
circulating source of amyloid â peptide (APP), accumulation of which is
believed to be the primary pathogenic mechanism in AD . Platelets are
known to play a vital role in the complications of atherosclerosis and
have been demonstrated to release APP within atheroma . Assuming that
platelet embolisation is important in the development of late onset AD
then anti-platelet medication should inhibit the onset or progression of
disease in a similar way to atherosclerosis. However, at present there is
no evidence to support this from the limited randomised trials completed
that have all utilised NSAIDs . Similarly, if the aetiology of
atherosclerosis and AD are similar the age-adjusted incidence of AD would
be expected to follow that of vascular disease which does not appear to be
the case . The findings of Purandare et al may equally reflect our
inability to differentiate vascular dementia and AD using clinical and
imaging criteria .
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Competing interests: No competing interests