About dementia

What is dementia?

What is dementia?

Dementia occurs as a result of a disease process that increasingly damages the brain over time. Signs and symptoms of dementia result when once-healthy neurons (nerve cells) in the brain stop working, lose connections with other brain cells, and die. While everyone loses some neurons as they age, people with dementia experience far greater loss.

Dementia is a syndrome (usually of a chronic or progressive nature) in which there is deterioration of cognitive functioning (thinking, remembering, and reasoning) and behavioral abilities. This loss is to such an extent that it interferes with a person's daily life and activities. These functions include memory, language skills, visual perception, problem solving, self-management, and the ability to focus and pay attention. The impairment in cognitive function is commonly accompanied, and occasionally preceded, by deterioration in social behaviour, motivation or emotional control, and their personalities may change. These difficulties occur because nerve cells (neurons) in parts of the brain involved in cognitive function have been damaged or destroyed. Consciousness is not affected.

While dementia is more common as people grow older (up to half of all people age 85 or older may have some form of dementia), it is not a normal part of aging. Many people live into their 90s and beyond without any signs of dementia.

Dementia stats- Worldwide & India

Dementia stats- Worldwide & India


Dementia affects all groups of society and is not linked to social class, gender, ethnic group, or geographic location. Worldwide, around 55 million people have dementia, and there are nearly 10 million new cases every year, implying 1 new case every 3.2 seconds.

The total number of people with dementia is expected to increase to 78 million by 2030 and 139 million by 2050.

Dementia is one of the major causes of disability and dependency among older people worldwide. The World Health Organization (WHO) infographic given below, includes information about the symptoms of dementia, the cause, the number of people affected and the cost.



As per Census of India 2011, the population of 60 years and above is 104 million (8.6% of the total population); amongst them, the population of 80 years and above is 11 million in India.

As per the Dementia India Strategy Report, an estimated 4.4 million people are living with dementia as of 2015. This number is projected to double by 2030 to 7.6 million and 14.3 million by 2050.

Types of dementia

Types of dementia

Dementia is caused by a number of diseases which destroy nerve cells and damage the brain. Various disorders and factors contribute to the development of dementia. Neurodegenerative disorders result in a progressive and irreversible loss of neurons and brain functioning.

The National Institute on Ageing; which is a Division of the U.S. National Institutes of Health
( ), states that other conditions have identified that can cause dementia or dementia-like symptoms. These conditions include:

  • Argyrophilic grain disease, a common, late-onset degenerative disease
  • Creutzfeldt-Jakob disease, a rare brain disorder
  • Huntington's disease, an inherited, progressive brain disease
  • Chronic traumatic encephalopathy (CTE), caused by repeated traumatic brain injury
  • HIV-associated dementia (HAD)

Other conditions that cause dementia-like symptoms can be halted or even reversed with treatment. For example, normal pressure hydrocephalus, an abnormal buildup of cerebrospinal fluid in the brain, often resolves with treatment.

What are the stages & symptoms of dementia?

Stages & symptoms of dementia

The rate of progression of dementia varies between people. The symptoms of dementia tend to get worse over time. Genetics, age, and overall health, as well as the underlying cause of the dementia might play a role in how fast the disease progresses.

Dementia has distinct stages that shape treatment and impact on health in different ways. The stages may often overlap. Symptoms may appear at certain stages, then resolve, while other health effects progressively get worse.

Dementia affects each person in a different way, depending upon the impact of the disease and the person’s personality before becoming ill.

As per the World Health Organization, the signs and symptoms linked to dementia can be understood in three stages:

Mild stages

The early stage of dementia is often overlooked, because the onset is gradual. Common symptoms include:

  • Forgetfulness
  • Losing track of time
  • Becoming lost in familiar places

Moderate stages

As dementia progresses to the middle stage, the signs and symptoms become clearer and more restricting. These include:

  • Becoming forgetful of recent events and people's names
  • Becoming lost at home
  • Having increasing difficulty with communication
  • Needing help with personal care
  • Experiencing behaviour changes, including wandering and repeated questioning

Severe stages

The late stage of dementia is one of near total dependence and inactivity. Memory disturbances are serious and the physical signs and symptoms become more obvious. Symptoms include:

  • Becoming unaware of the time and place
  • Having difficulty recognizing relatives and friends
  • Having an increasing need for assisted self-care
  • Having difficulty walking
  • Experiencing behaviour changes that may escalate and include aggression

How is dementia diagnosed?

How is dementia diagnosed?

There is no single test for diagnosing dementia. Instead, physicians, often with the help of specialists such as neurologists and geriatricians, use a variety of approaches and tools to help make a diagnosis.

To diagnose dementia, doctors first assess whether a person has an underlying treatable condition such as abnormal thyroid function, normal pressure hydrocephalus, or a vitamin deficiency that may relate to cognitive difficulties. Early detection of symptoms is important, as some causes can be treated. In many cases, the specific type of dementia a person has may not be confirmed until after the person has died and the brain is examined.

The National Institute on Ageing; which is a Division of the U.S. National Institutes of Health (, states that a medical assessment for dementia generally includes:


Medical history
Typical questions about a person's medical and family history might include asking about whether dementia runs in the family, how and when symptoms began, changes in behavior and personality, and if the person is taking certain medications that might cause or worsen symptoms.


Physical examination
Measuring blood pressure and other vital signs may help physicians detect conditions that might cause or occur with dementia. Some conditions may be treatable.


Neurological tests
Assessing balance, sensory response, reflexes, and other cognitive functions help identify conditions that may affect the diagnosis or are treatable with drugs.

Other procedures are also used to diagnose dementia. These are:

Other procedures are also used to diagnose dementia. These are:

  • Cognitive and neuropsychological tests
  • Laboratory tests
  • Psychiatric evaluation
  • Genetic tests
  • Brain scans such as Computed tomography (CT), Magnetic resonance imaging (MRI), positron emission tomography (PET)

Diagnosing dementia requires a careful and comprehensive medical evaluation. Although physicians can almost always determine if a person has dementia, it may be difficult to identify the exact cause. Several days or weeks may be needed for the individual to complete the required tests and examinations and for the physician to interpret the results and make a diagnosis.

Dementia & stigmatization

Dementia & stigmatization

People with dementia and their carers and families are often stigmatized. Stigma linked to dementia is due to lack of awareness and understanding about the disease, leading to fear. The stigma associated with dementia is a major concern for people with dementia, and specially for their carers and families. Stigma is one of the most important factors that leads to delay and avoidance of diagnosis and care.

Dementia is a demanding condition. It can be overwhelming, not only for the people who have it, but also for their carers and families. The impact of dementia on carers, family can be physical, psychological, social and economic. The society should not judge those who seek professional care for their parents with dementia. Stigma should not be attached to persons with dementia, and their families. Managing dementia at home for the family eventually tends to become very challenging. Providing professional care for someone with dementia is imperative. Children are not seeking assisted living for their parents because they are shrugging their responsibilities, but because they are being more sensitive and seeking highest quality of life for their elderly parents. A specialized dementia care assisted living home is the right place for the persons with dementia (PwD), when required.

Global action plan on the public health response to dementia 2017-2025

Global action plan on the public health response to dementia 2017-2025

The Global action plan on the public health response to dementia 2017-2025 was adopted by World Health Organization (WHO) Member States at the 70th World Health Assembly in May 2017. It aims to improve the lives of people with dementia, their carers and families, while decreasing the impact of dementia on communities and countries. It provides a set of actions to realize the vision of a world in which dementia is prevented and people with dementia and their carers receive the care and support they need to live a life with meaning and dignity. For more details:

Resources to help you better understand & manage dementia

Resources to help you better understand & manage dementia

Being a caregiver for a loved one living with dementia can be very overwhelming. You are not alone! There are a lot of resources available online that can help you better understand the disease, its progression and how to approach caregiving. These resources will help to decrease problems associated with caregiving and to improve the quality of life families and caregivers of people with dementia. Here are some that we recommend:

Relevant dementia-related articles:

Know more about our dementia care program