Dementia

What is dementia?

Dementia is a loss of mental functions severe enough to interfere with daily life. It is not a single disease, but a group of symptoms caused by several conditions that affect the brain. Dementia can affect:

• Memory
• Language
• Visual perception (making sense of what you see)
• Problem-solving
• Everyday tasks
• The ability to focus and pay attention

Some forgetfulness is normal with age. Dementia is different — it is a serious brain condition that disrupts daily life.

About 57 million people worldwide live with dementia (WHO, 2021), with nearly 10 million new cases a year. Over 60% live in low- and middle-income countries, including India — and the burden is rising rapidly as our population ages. Dementia is now the seventh leading cause of death globally.

What are the types of dementia?

The most common types are neurodegenerative — diseases where brain cells stop working or die. They include:

• Alzheimer's disease — the most common form (60–70% of cases). Abnormal deposits of beta-amyloid plaques and tau tangles form in the brain.
• Lewy body dementia — causes movement symptoms along with cognitive decline; Lewy bodies are abnormal protein deposits.
• Frontotemporal disorders — affect the frontal or temporal lobes; frontal-lobe changes cause behavioural symptoms, temporal-lobe changes cause language and emotional symptoms.
• Vascular dementia — caused by changes in the brain's blood supply, often after a stroke or due to atherosclerosis.
• Mixed dementia — more than one type present at once, for example Alzheimer's with vascular dementia.

Other conditions that can cause dementia or dementia-like symptoms include Creutzfeldt-Jakob disease, Huntington's disease, chronic traumatic encephalopathy (repeated head injury), and HIV-associated dementia.

Who is at risk for dementia?

Risk factors include:

• Age — the biggest risk factor
• Smoking
• Uncontrolled diabetes
• High blood pressure
• Drinking too much alcohol
• Physical inactivity
• Hearing loss
• Close family member with dementia

What are the symptoms of dementia?

Symptoms depend on which parts of the brain are affected. Forgetfulness is often the earliest sign. People with dementia may:

• Get lost in familiar places
• Use unusual words for familiar objects
• Forget a close family member or friend's name
• Forget older memories
• Need help with tasks they used to do independently

Some people lose control of their emotions, and personality may change — they may become apathetic or lose inhibitions. Certain types also cause balance and movement difficulties.

Dementia progresses from mild (just beginning to affect function) to severe (complete dependence on others for care).

How is dementia diagnosed?

A doctor uses several tools to make a diagnosis:

• Medical history and symptom review
• Physical examination
• Tests of thinking, memory, and language
• Blood tests, sometimes genetic tests, and brain scans (CT or MRI)
• Mental-health evaluation, to see whether depression or another condition is contributing

What are the treatments for dementia?

There is no cure for most types of dementia, including Alzheimer's and Lewy body dementia. Treatment focuses on maintaining function as long as possible and managing symptoms:

• Medicines may temporarily improve memory and thinking in some people, or slow decline. Other medicines can treat anxiety, depression, sleep problems, and muscle stiffness. Some of these can have strong side effects in older adults — discuss options carefully with the doctor.
• Occupational therapy — ways to make everyday tasks easier.
• Speech therapy — for swallowing difficulties or unclear speech.
• Mental-health counselling — for the person and family, to help manage difficult emotions and plan for the future.
• Music or art therapy — can reduce anxiety and improve well-being.
• Lifestyle support — regular routines, safe home environment, familiar activities, and physical activity such as walking or yoga.

Family carers of people with dementia carry a significant share of the load — globally, carers provide about 5 hours of care per day on average. Respite services, support groups, and counselling for carers themselves are important. Specialised memory clinics exist in most major Indian cities.

Can dementia be prevented?

There is no proven way to prevent dementia, but controlling risk factors may help: manage blood pressure and diabetes, don't smoke, limit alcohol, stay physically active, keep socially connected, eat a healthy diet, and treat hearing loss when it occurs.