Are Population-Level Approaches to Dementia Risk Reduction UnderResearched? A Rapid Review of the Dementia Prevention Literature

Dementia is forecast to become increasingly prevalent,
particularly in low- and middle-income countries, and is
associated with high human and economic costs. Primary
prevention of dementia -preventing risk factors leading to
disease development - is an emerging global public health
priority. Primary prevention can be achieved in two ways:
individual-level or population-level. In this rapid review, we
quantify the proportion of contributing interventional evidence
to the dementia primary prevention literature that is concerned
with either approach. We searched Medline, the National
Institute for Health and Care Excellence, Cochrane, the World
Health Organization, and Google to identify systematic reviews
that described primary prevention interventions for dementia.
We used search terms related to dementia risk reduction,
intervention/policy, and review. We analysed reference lists of
included dementia prevention reviews to identify contributing
primary prevention evidence, and categorised these as
either individual-level or population-level. Additionally, we
examined search strategies to investigate the likelihood of
reviews identifying available population-level interventions.
We included twelve of the 527 articles retrieved. Population-level evidence was summarised by only two reviews. In these
two reviews, population-level interventions. Most search strategies were
weighted towards identifying individual-level evidence.
Existing systematic reviews of dementia primary prevention
interventions include almost no population-level evidence.
Correction of this imbalance is needed to ensure that dementia
prevention policies can achieve meaningful reductions in the
prevalence of, and inequalities in, dementia.