160719 Risk reduction of cognitive decline and dementia
Dementia is a rapidly growing global public health problem. Worldwide, around 50 million people have dementia, with approximately 60% living in low- and middle-income countries (LMIC). Every year, there are nearly 10 million new cases. The total number of people with dementia is projected to reach 82 million in 2030 and 152 million in 2050. Dementia leads to increased costs for governments, communities, families and individuals, and to loss in productivity for economies. In 2015, the total global societal cost of dementia was estimated to be US$ 818 billion, equivalent to 1.1% of global gross domestic product (GDP).
Crucially, while age is the strongest known risk factor for cognitive decline, dementia is not a natural or inevitable consequence of ageing. Several recent studies have shown a relationship between the development of cognitive impairment and dementia with lifestylerelated risk factors, such as physical inactivity, tobacco use, unhealthy diets and harmful use of alcohol. Certain medical conditions are associated with an increased risk of developing dementia, including hypertension, diabetes, hypercholesterolemia, obesity and depression. Other potentially modifiable risk factors include social isolation and cognitive inactivity. The existence of potentially modifiable risk factors means that prevention of dementia is possible through a public health approach, including the implementation of key interventions that delay or slow cognitive decline or dementia.
In May 2017, the Seventieth World Health Assembly endorsed the Global action plan on the public health response to dementia 2017–2025 (WHO, 2017a). The action plan includes seven strategic action areas and Executive Summary xi dementia risk reduction is one of them. The action plan calls upon the WHO Secretariat to strengthen, share and disseminate an evidence base to support policy interventions for reducing potentially modifiable risk factors for dementia. This involves providing a database of available evidence on the prevalence of those risk factors and the impact of reducing them; and supporting the formulation and implementation of evidence-based, multisectoral interventions for reducing the risk of dementia.
The risk reduction guidelines for cognitive decline and
dementia are aligned with WHO’s mandate to provide evidence-based guidance for
a public health response to dementia.
 Risk reduction of cognitive decline and dementia: WHO guidelines. Geneva: World Health Organization; 2019. License: CC BY-NC-SA 3.0 IGO.