Key facts
- In 2021, 57 million people were living with dementia worldwide, over 60% of whom live in low-and middle-income countries. Every year, there are nearly 10 million new cases.
- Dementia results from a variety of diseases and injuries that affect the brain. Alzheimer disease is the most common form of dementia and may contribute to 60–70% of cases.
- Dementia is currently the seventh leading cause of death and one of the major causes of disability and dependency among older people globally.
- In 2019, dementia cost economies globally US$ 1.3 trillion, approximately 50% of these costs are attributable to care provided by informal carers (e.g. family members and close friends), who provide on average 5 hours of care and supervision per day.
- Women are disproportionately affected by dementia, both directly and indirectly. Women experience higher disability-adjusted life years and mortality due to dementia, but they also provide 70% of care hours for people living with dementia.
Overview
Dementia is a condition that affects memory, thinking and the ability to perform daily activities. It can be caused by many different diseases that damage the brain.
Dementia gets worse over time. Although more common after age 65, it is not an inevitable part of ageing.
Things that increase the risk of developing dementia include:
- health conditions such as high blood pressure (hypertension), high blood sugar (diabetes), being overweight or obese, depression, vision and hearing loss, poor sleep, traumatic brain injury and stroke;
- lifestyle factors such as smoking tobacco, harmful alcohol use, physical inactivity, social isolation, and low educational attainment; and
- environmental factors such as air pollution.
Dementia can be caused by several diseases which over time damage the brain, typically leading to deterioration in cognitive function beyond what might be expected from the usual consequences of biological ageing. The impairment in cognitive function is commonly accompanied, and occasionally preceded, by changes in mood, emotional control, behaviour or motivation.
Dementia has physical, psychological, social and economic impacts, not only for people living with dementia, but also for their carers, families and society at large. There is often a lack of awareness and understanding of dementia, resulting in stigmatization and barriers to diagnosis and care.
Signs and symptoms
Dementia can affect memory, thinking, communication, mood, and behaviour. As symptoms worsen, so does the need for daily support.
Early signs and symptoms are:
- forgetting things or recent events
- losing or misplacing things
- getting lost when walking or driving
- being confused, even in familiar places
- losing track of time
- difficulties solving problems or making decisions
- problems following conversations or trouble finding words
- difficulties performing familiar tasks
- misjudging distances to objects visually.
Changes in mood and behaviour sometimes happen even before memory problems occur. Common changes include:
- feeling anxious, sad, or angry about memory loss
- personality changes
- inappropriate behaviour
- withdrawal from work or social activities
- being less interested in other people’s emotions.
Dementia affects each person in a different way, depending upon the underlying causes, other health conditions and the person’s cognitive functioning before becoming ill.
Symptoms vary from person to person and usually become more severe over time. Some symptoms may appear only in the later stages of dementia.
As the condition progresses, the need for help with personal care increases. People with dementia may not be able to recognize family members or friends, develop difficulties moving around, lose control over their bladder and bowels, have trouble eating and drinking and experience behaviour changes such as aggression that are distressing to the person with dementia as well as those around them.
Common forms of dementia
Dementia is caused by many different diseases or injuries that damage the brain. Alzheimer disease is the most common form and contributes to 60–70% of cases. Other forms include vascular dementia, dementia with Lewy bodies (abnormal deposits of protein inside nerve cells), and a group of diseases that contribute to frontotemporal dementia (degeneration of the frontal lobe of the brain).
Dementia may also develop after a stroke, in the context of certain infections such as HIV, as a result of harmful use of alcohol, after repeated injuries to the brain, or because of nutritional deficiencies. The boundaries between different forms of dementia are not always clear and mixed forms often co-exist.
Treatment and care
There is no cure for dementia, but a lot can be done to support people living with dementia and those who care for them.
Non-pharmacological interventions can improve quality of life and daily functioning. These may include rehabilitation, psychoeducation, physical activity, social engagement, cognitive stimulation and support for carers.
Some medications can help manage dementia symptoms:
- Cholinesterase inhibitors like donepezil are used to treat Alzheimer disease.
- NMDA receptor antagonists like memantine are used for severe Alzheimer disease and vascular dementia.
- Medicines to control blood pressure and cholesterol can prevent additional damage to the brain due to vascular dementia.
- Selective serotonin reuptake inhibitors (SSRIs) can help with severe symptoms of depression in people living with dementia if lifestyle and social changes don’t work, but these should not be the first option.
If a person living with dementia is at risk of hurting themselves or others, non-pharmacological approaches should be tried first. Only when clearly needed, medicines like haloperidol and risperidone may be considered with caution, under close supervision.
Self-care
For those diagnosed with dementia, there are things that can help manage symptoms to maintain quality of life and well-being:
- stay physically active
- eat healthily
- stop smoking and drinking alcohol
- get regular check-ups with your doctor
- write down everyday tasks and appointments to help you remember important things
- keep up your hobbies and do things that you enjoy
- try new ways to keep your mind active
- spend time with friends and family and engage in community life.
Plan ahead of time. Over time, it may be harder to make important decisions for yourself or your finances:
- identify people you trust to support you in making decisions and help you communicate your choices
- create an advance plan to tell people what your choices and preferences are for care and support
- bring your ID with your address and emergency contacts when leaving the house
- reach out to family and friends for help
- talk to people you know about how they can help you
- join a local support group.
It is important to recognize that providing care and support for a person living with dementia can be challenging, impacting the carer’s own health and well-being. As someone supporting a person living with dementia, reach out to family members, friends, and professionals for help. Take regular breaks and look after yourself. Try stress management techniques such as mindfulness-based exercises and seek professional help and guidance if needed.
To help carers look after themselves and the person
they support, WHO creatediSupport,a self-help programme that offers practical skills
and training for people caring for someone living with dementia.
Risk factors and prevention
Although age is the strongest known risk factor for
dementia, dementia can also affect younger people, and young-onset dementia – in
which symptoms begin before the age of 65 – accounts for up to 9% of cases.
Evidence suggests that people can reduce the risk of
cognitive decline and dementia by adopting healthy behaviours and lifestyles,
managing health conditions that are known to increase the risk for dementia,
and reducing environmental risk factors.
Important actions include:
- being physically active
- not smoking
- avoiding harmful alcohol use
- eating a healthy, balanced
diet - staying socially and
cognitively active - maintaining a healthy weight
- managing blood pressure,
cholesterol and blood sugar levels - using hearing aids where
needed - reducing exposure to air
pollution.
Dementia risk accumulates across the life course, and some risk factors may have a greater impact at particular stages of life.
Social factors such as poverty, limited education and unequal access to employment and health care can also influence the risk of dementia. Reducing risk therefore requires not only
individual action, but also supportive systems and policies that shape people’s
everyday lives.
The WHO guidelines on risk
reduction of cognitive decline and dementia, second edition, provide
comprehensive, practical recommendations to support countries, health systems
and communities in integrating dementia risk reduction into policies and
programmes.
Human rights
Unfortunately, people living with dementia are
frequently denied the basic rights and freedoms available to others.
In many countries, physical and chemical restraints
are used extensively in care homes for older people and in acute-care settings,
even when regulations are in place to uphold the rights of people to freedom
and choice.
An appropriate and supportive legislative
environment based on internationally accepted human rights standards is
required to ensure the highest quality of care for people with dementia and
their carers.
WHO response
WHO recognizes dementia as a public health priority. In May 2017, the World Health Assembly endorsed the Global action plan on the public health response to dementia 2017-2025, extended to 2031. The Plan provides a comprehensive blueprint for action for policy-makers, international, regional and national partners, and WHO in the following areas: addressing dementia as a public health priority; increasing awareness of dementia and creating a dementia-inclusive society; reducing the risk of dementia; diagnosis, treatment and care; information systems for dementia; support for dementia carers; and research and innovation
To facilitate the monitoring of the global dementia action plan, WHO developed the Global Dementia Observatory (GDO), a data portal that collates country data on 35 key dementia indicators across the global action plan’s seven strategic areas. As a complement to the GDO, WHO launched the GDO Knowledge Exchange Platform, which is a repository of good practices examples in the area of dementia with the goal of fostering mutual learning and multi-directional exchange between regions, countries and individuals to facilitate action globally.
