Preventing dementia; the role of vascular risk factors
background Dementia affects over 24
million people in the world currently and the
number with dementia is expected to increase to
over 81 million by 2040. The prevalence of dementia
would be reduced by 50% if risk reduction strategies
were successful in delaying the onset of
dementia by five years.
aim The talk will review the epidemiological
and randomised controlled trial (rct) evidence
for following strategies that are particularly
amenable to therapeutic intervention: control of
risk factors for cerebrovascular disease, antiinflammatory
drugs, anti-oxidants, and increasing
neuronal reserve.
methods A selective review of the literature
was conducted using MedLine to identify current
evidence for role of vascular risk factors as
potential targets in preventing dementia. Crossreferences
were hand searched.
results The epidemiological evidence
suggests that it is possible to delay, if not prevent,
the onset of dementia, both Alzheimer's disease
and vascular dementia. There is limited rct evidence
to support anti-hypertensives but not for
other strategies.
conclusion The talk will discuss the
likely reasons for the observed dissonance between
the epidemiological research that identifies
potential risk factor and the rct that fails to show
positive effect of the intervention in older people
with mild cognitive impairment (mci). They
include limitations of methodologies, therapeutic
time window and unsuspected mechanisms of
action of individual drugs. It will discuss the additive
effect of multiple risk factors and present preliminary
findings on asymptomatic cerebral
emboli as a novel and potentially amenable risk
factor in prevention of dementia.