Dementia is a disease of the brain characterized by progressive deterioration in brain function including memory, learning, orientation, language, comprehension and judgment. The irreversible decline in intellectual and physical functioning affects the person with dementia and causes significant distress to their family and carers. Moreover, dementia is not merely a problem of memory. It reduces the ability to learn, reason, retain or recall past experience and there is also loss of patterns of thoughts, feelings and activities. Dementia also results in a progressive decline of cognitive abilities, poor self-healthcare, physical dependency, wandering, aggression and difficult behaviours. The World Health Organization (WHO) predicts that by 2025 about 75% of the estimated 1.2 billion people aged 60 years and above will reside in developing countries. As per estimates made in the World Alzheimer Report 2015, over 4.2 million people in India are affected by Dementia.
Dementia is an umbrella term for all the progressive neuro-degenerative conditions which affect the brain and are severe enough to interfere with normal functioning. It generally affects the elderly population above the age of 60 but is not a normal process of ageing. Unfortunately there is no cure for dementia, but certain conditions are reversible. If any form of dementia occurs at an age less than 60 years, such cases are termed as early onset. Alzheimer’s disease is one of the most common form of dementia, amounting to 60-70% of the cases. Other conditions include vascular dementia, Lewy body dementia, mixed dementia, Creutzfeldt-Jakob disease, Parkinson’s disease dementia and Huntington’s disease.
1. Neurological diseases including Alzheimer's disease, Parkinson's disease, Huntington's disease, and some types of multiple sclerosis.
2. Vascular disorders. These are disorders that affect the blood circulation in your brain, eg. Stroke
3. Traumatic brain injuries caused by car accidents, falls, concussions, etc.
4. Infections of the central nervous system. These include meningitis, HIV, and Creutzfeldt-Jakob disease.
5. Long-time alcohol or drug use
1.Alzheimer’s Disease: This is the most common form of dementia. Alzheimer’s disease accounts for an estimated 60-80% of cases. It is a neurological disorder in which the death of brain cells causes memory loss and cognitive decline. The disease starts mild and gets progressively worse
2.Creutzfeldt-Jakob Disease: Also called mad-cow disease, Creutzfeldt-Jakob disease occurs in cattle, and has been transmitted to people under certain circumstances. It is a rapidly fatal disorder that impairs memory and coordination, and causes behavior changes.
3. Dementia with Lewy bodies: It is the second most common type of progressive dementia after Alzheimer’s disease. The condition causes a progressive decline in mental abilities. In Lewy body dementia, protein deposits, called Lewy bodies, develop in nerve cells in regions of your brain involved in thinking, memory and movement (motor control).
4. Frontotemporal Dementia: Frontotemporal dementia (FTD) affects the brain in frontal and temporal lobes, which control planning and judgment; emotions, speaking and understanding speech; and certain types of movement. FTD includes a range of specific disorders with different core symptoms. But there’s significant symptom overlap, especially as these disorders progress. The age of onset is 50‘s or early 60’s. It’s also known as Pick’s Disease.
5. Huntington’s Disease: Huntington’s disease is a progressive brain disorder caused by a single defective gene on chromosome 4 — one of the 23 human chromosomes that carry a person’s entire genetic code. It is a genetic disorder and leads to dementia. Symptoms of Huntington’s disease usually develop between ages 30 and 50, but they can appear as early as age 2 or as late as 80.
6. Mixed Dementia: In mixed dementia, abnormalities linked to more than one type of dementia occur simultaneously in the brain.
7.Vascular Dementia: Vascular dementia is the second most common cause of dementia. The brain is damaged either due to repeated small strokes causing lack of blood supply (ischemic) or small bleeds (hemorrhagic). The arteries in the brain can get damaged due to hypertension, diabetes and cardiac problems. Vascular dementia also affects memory, planning, motor moments and thinking like Alzheimer’s, however, the progression here is stepwise.
8.Wernicke-Korsakoff Syndrome: It is a chronic memory disorder caused by severe deficiency of thiamine (vitamin B-1). The most common cause is alcohol misuse. It leads to memory issues and loss of social skills. This condition is reversible and can be treated.
Dementia develops gradually, the early signs may be very subtle and vague, and not immediately obvious.
There is no definitive diagnosis for dementia; diagnosis is made by a process of elimination of alternatives. The process involves:
Medical history – past and current medical problems, family medical history, any medications being taken, and the problems with memory, thinking or behaviour that are causing concern
Physical examination – tests of the senses and movement function, as well as heart and lung function, to help rule out other conditions
Laboratory tests – a variety of blood and urine tests to identify any possible illness which could be responsible for the symptoms
Neuropsychological or cognitive testing – a variety of tests are used to assess thinking abilities including memory, language, attention and problem solving.
Brain imaging – there are certain scans that look at the structure of the brain and are used to rule out brain tumours or blood clots in the brain as the reason for symptoms, and to detect patterns of brain tissue loss that can differentiate between different types of dementia.
Psychiatric assessment – to identify treatable disorders such as depression, and to manage any psychiatric symptoms such as anxiety or delusions which may occur alongside dementia.
Dementia is not treatable, although some of its symptoms may be controlled. In the early stages, the Person with Dementia may be managed at home, whereas as the condition advances, more professional care may be necessary.
Several key risk factors for dementia have been identified:
< Ageing
< Genetics
< Medical history, particularly cardiovascular problems
< Lifestyle and environment
There is no single straightforward cause of dementia, and no way of definitely preventing it, but it may be possible for each of us to reduce our risk or at least delay the onset of dementia.
Visit a Memory Clinic and meet with the experts there to get an assessment. NMT runs online and offline Memory Clinics.
NMT helps you provide the best care in every stage of the disease.