Dementia

Posted On April 21, 2020

Dementia is a progressive decline in cognitive function. It may involve one or more areas of the brain functions. The chance of having dementia increases with age. As more people lives to an advanced age, the number of people affected by dementia is rapidly rising.

Types of dementia

• Mild cognitive impairment (MCI): between normal and dementia.
• Alzheimer’s disease (AD): is the most common type
  • consisted of 60 to 80% of dementia,
• Vascular dementia
• Chronic traumatic encephalopathy
• Alcohol related dementia
• Pseudo dementia or dementia mimics: cognitive impairment caused by mood disorder or chemical imbalance in the body.
• Dementia with Lewy bodies (DLB)
• Fronto-temporal Dementia (FTD)
• Parkinson disease dementia (PDD)
• Numerous other less common diseases such as:
  • Increased pressure in brain from bleeding, tumor
  • Infection of the brain
  • Metabolic, nutritional problems

Early onset dementia

• Dementia usually affects the older age group, at times patient who are at a young age may also be affected.
• A study in UK found that for dementia involving patients at age 30-65 years old, the following diagnosis were made:
  • Alzheimer’s disease: 34%
  • Vascular dementia: 18%
  • Frontotemporal dementia: 12%
  • Dementia with lewy bodies: 7%
  • Alcohol related: 10%
  • Others: 19%

As you can see from the above list, there are many different types of dementia. The most type is Alzheimer’s disease, but it is important to exclude the other possibilities.

It will not be possible to completely discuss all the different types of dementia here. We will go through the more common types, especially Alzheimer’s disease.

How a diagnosis is made?

• History: the physicians will evaluate a patient’s prior functional level, rate of progression, and any associated illness.
• Neurological examination
• Cognitive testing: most commonly used is Mini mental status exam (MMSE), there are many other tests available.
• Scans (imaging study): Most commonly used is MRI scan, which is more accurate than a CT scan.
• EEG may sometimes be used
• Blood test: American Academy of Neurology recommends a minimum of : B12, TSH, CBC. Other blood test may also be needed depending on the situation.

Alzheimer’s disease (AD)

• Usually starts after 60 years old
• The cause of AD is not known.
• Memory problem: slowly progressive loss of memory
• Patient may become less organized, less motivated, unable to perform several function at the same time, impaired insight, inability to complete tasks.
• It is common for patient to underestimate or deny any problem.
• Sleep and Behavioral disturbances are common
• Seizure: 10-20 percent of patients may develop a seizure, especially at a late stage.
• Typically: blood tests are normal, MRI head showed some atrophy, but otherwise normal for age for AD patients.

Clinical dementia rating Scale: MD Calc CDR scale – link

• 0 =No dementia
• 0.5 = questionable
• 1 = mild: moderate memory loss, oriented to place, not to time
• 2 = moderate: severe memory loss, disoriented to time, place
• 3 = Severe, oriented to person only

Medical treatment

• Cholinesterase inhibitors: to raise the level of Acetylcholine in the brain. Usually started on initial diagnosis of dementia.
  • donepezil: most commonly used medication.
    • start with 5 mg daily, increase to 10 mg daily.
  • Other drugs: Galantamine, Rivastigmine
  • Rivastigmine also comes in a skin patch
• Memantine:
  • usually added to above when dementia become more advanced, when MMSE < 18
• Vitamine E at 2000 IU daily, may have questionable benefit, but is a fairly safe medication.
  • this medication should not be taken with Memantine.

Management & Support

• Adequate nutrition
• Exercise program
• Treatment of risk factors for stroke and heart disease

Frontotemporal dementia

• Main symptoms
  • Prominent changes in social behavior and personality
    • Disinhibition: inappropriate touching, public urination
    • loss of interest, motivation
    • Crave for certain food
    • Compulsive behaviors
  • Severe word finding difficulties
  • Motor problem
• Tends to start around the age of sixties
• MRI scan: may show frontal or temporal atrophy, one side affected more than the other side

Vascular dementia

• Dementia related to blood flow problem in the brain.
• May occur after a known or a silent stroke.
• 20-25 percent of patient with dementia
• May combine with other form of dementia especially Alzheimer’s dementia.
• Risk factors for having vascular dementia:
  • advanced age
  • Hypertension, Diabetes, elevated cholesterol level
  • Low physical activity, overweight
  • smoking
  • coronary artery disease, atrial fibrillation
• Treatment is mainly directed to prevention of the above risk factors.

Dementia with Lewy bodies

• Main symptoms
  • Fluctuation in cognitive function, and variation in attention and alertness
  • Visual hallucinations
  • Sleep behavior problems
  • Parkinsonian features: such as slowness of movement, stiffness
  • visuospatial difficulty
• Other frequently associated symptoms include
  • overly sensitive to neuroleptic medications
  • Falls, passing out, low blood pressure, bladder problem
  • depression is common

Treatment of behavior problem in Dementia

• Very little clear treatment guideline available
• Different doctors have different ways of treating the behavior
• problem.

Caregiver help

• UCLA Health – Alzheimer’s and dementia Care Video
• UCLA Health – Alzheimer’s and dementia on You tube