October 03 2019 at 03:28 PM by Biswajeet Sahoo
Dementia, neurodegenerative disease, is not a single disease in itself, but is a broad category of brain diseases that causes long-term and gradual deterioration in cognitive function basically in the ability to think and remember. It affects a person's ability to judge and communicate and learn. It is preceded, by deterioration in emotional control, social behaviour, or motivation. It is usually of a chronic or progressive nature. Although dementia mainly affects older people, it is not a normal part of ageing. There is no known cure for dementia.
According to Alzheimer’s and Related Disorders Society of India, there are 3.7 million Indians with dementia. It is projected that around one in five persons from low-and middle-income countries are going to be above 60 years of age by 2050. According to World Health Organization (Updated September 2019) worldwide, around 50 million people have dementia, with nearly 60% living in low- and middle-income countries. In 2015, 46.8 million people live with dementia, with 58% living in low and middle income countries. Dementia is now the 5th leading cause of death. Alzheimer's disease is the most common form of dementia and may contribute to 60–70% of cases. About 3% of people between the ages of 65–74 have dementia, 19% between 75 and 84, and nearly half of those over 85 years of age. The annual incidence of dementia is over 9.9 million worldwide. Almost half of the new cases of dementia occur in Asia, followed by Europe (25%), the Americas (18%) and Africa (8%). The incidence of dementia increases exponentially with increase in age, doubling with every 6.3 year increase in age. Dementia affecting 5% of the population older than 65 and 20–40% of those older than 85.Rates are slightly higher in women than men at ages 65 and greater.
Types of Dementia
1. Vascular Dementia-It is the second most common type of dementia and is caused by damage to the vessels that supply blood to brain. It can be caused by strokes or damage of the brain. The common symptoms of vascular dementia include difficulties with problem-solving, focus, slowed thinking, and organization. It’s proportion of dementia cases is about 20-30.
2. Dementia With Lewy Bodies (DLB)- Presence of Cortical Lewy bodies (alphasynuclein) in brain. This is one of the more common types of progressive dementia. It’s proportion of dementia cases is about <5%.
3. Frontotemporal Dementia (FTD)-People above the age of 80 are prone to this type of dementia. It is caused due to damage limited to frontal and temporal lobes of the brain. It’s proportion of dementia cases is about 5-10%.
4. Alzheimer’s disease (AD)-Caused by Cortical amyloid plaques and neurofibrillary tangles in brain. It’s proportion of dementia cases is about 50-75%.
5. Mixed Dementia- It is a combination of several causes, such as Alzheimer's disease, vascular dementia and Lewy body dementia. It’s proportion of dementia cases is about 10-15%.
Causes of Dementia
Dementia is caused by damage to or loss of nerve cells in brain. The damaged nerve cells they lose their ability to communicate with other cells, leading to dysfunction.
Risk factors for dementia include
2. Heavy alcohol use
4. High blood pressure
5. Hardening of the blood vessels
7. High cholesterol
8. Family history
9. Head trauma
12.Mutation on 1,14,21 chromosome
15.Nutritional deficiency (B vits)
Signs and symptoms
1. Signs and symptoms of dementia are varied from person to person, but typically include:
2. Memory loss
3. Problems with speaking or communicating (word-finding difficulties, repetition)
4. Problems focusing
5. Impaired judgment
6. Struggles completing tasks
7. Have difficulty in the recollection of facts, places etc.
8. Difficulty in understanding
9. Mood swing
To diagnose dementia clinicians focus their assessments on impairment in memory and other cognitive functions and loss of independent living skills. The focus is on the ABC symptoms of dementia i.e., the Activities of Daily Living (ADL), the Behavioural and Psychological Symptoms of Dementia (BPSD), and the Cognitive and memory symptoms.
No medications have been shown to prevent or cure dementia. Medications may be used to treat the behavioural and cognitive symptoms Acetylcholinesterase inhibitors, such as donepezil, may be useful for Alzheimer disease and dementia in Parkinson's, DLB, or vascular dementia. N-methyl-D-aspartate (NMDA) receptor blockers such as memantine may be of benefit. Usually depression is frequently associated with dementia, selective serotonin reuptake inhibitors (SSRIs) like sertraline and citalopram can reduce symptoms. Bbenzodiazepines such as diazepam, and non-benzodiazepine hypnotics, should be avoided due to the risks of increased cognitive impairment.