What is dementia?

Dementia is not a specific disease. It is a descriptive term for a collection of symptoms that can be caused by a number of disorders that affect the brain. People with dementia have significantly impaired intellectual functioning that interferes with normal activities and relationships. They also lose their ability to solve problems and maintain emotional control, and they may experience personality changes and behavioral problems, such as agitation, delusions, and hallucinations. While memory loss is a common symptom of dementia, memory loss by itself does not mean that a person has dementia. Doctors diagnose dementia only if two or more brain functions – such as memory and language skills — are significantly impaired without loss of consciousness.  Some of the diseases that can cause symptoms of dementia are Alzheimer’s disease, vascular dementia, Lewy body dementia, frontotemporal dementia, Huntington’s disease, and Creutzfeldt-Jakob disease.  Doctors have identified other conditions that can cause dementia or dementia-like symptoms including reactions to medications, metabolic problems and endocrine abnormalities, nutritional deficiencies, infections, poisoning, brain tumors, anoxia or hypoxia (conditions in which the brain’s oxygen supply is either reduced or cut off entirely), and heart and lung problems.  Although it is common in very elderly individuals, dementia is not a normal part of the aging process.

what are the risk factors of Dementia?

  • Age
    • age 70-74: 1%
    • age 75-79: 2%
    • over age 85: 8.4%
  • Family hx of AD or Parkinson’s (10-30% risk of AD in patients with first degree relative)
  • Head trauma
  • Depression
  • Low educational attainment?
  • hyperlipidemia
  • Diabetes
  • HTN

Modifiable Causes of Dementia:

  • Medications
  • Alcohol
  • Metabolic (b12, thyroid, hyponatremia, hypercalcemia, hepatic and renal dysfunction)
  • Depression? (likely marker though…)
  • CNS neoplasms, chronic subdural
  • NPH

What other medical conditions could present with dementia-like symptoms?

  • Depression
  • Normal Pressure hydrocephalus
    • Triad: Gait disturbance; Urinary incontinence; Cognitive dysfunction
  • Creutzfeldt-Jacob disease
    • Rapid onset and deterioration
    • Motor deficits
    • Seizures
    • Slowing and periodic complexes on EEG
    • Myotonic activity

What are the diagnostic criteria of dementia?

DSM-V criteria for diagnosis of demntia is:

  1. Memory impairment
  2. At least one of the following:
    • Aphasia
    • Apraxia
    • Agnosia
    • Disturbance in executive functioning
  3. Disturbance in 1 and 2 interferes with daily function
  4. Does not occur exclusively during delirium

What is Alzheimer'ss Disease?

  1. Onset usually near age 65; older age, more likely diagnosis
  2. Absence of focal neurological signs (but significant overlap in the elderly with hx of CVAs…)
  3. Aphasia, apraxia, agnosia
  4. Personality changes
  5. 60-80% of cases of dementia in older patients
  6. Memory loss
  7. Personality changes
  8. Global cognitive dysfunction and functional impairments
  9. Visual spatial disturbances (early finding)
  10. Apraxia
  11. Language disturbances
  12. Personality changes
  13. Delusions/hallucinations (usually later in course)
  14. Depression occurs in 1/3
  15. Normal/nonspecific EEG

What are the different types of dementia?

Vascular dementia:

  1. Onset of cognitive deficits associated with a stroke
  2. Abrupt onset of symptoms followed with step-wise deterioration
  3. Neurological symptoms
  4. Likelihood of AD and vascular disease significantly increases with age, therefore likelihood of both does as well…

Dementia with Parkinson’s:

  • Risk Factors:
    • Age over 70
    • Depression
    • Confusion/psychosis on levodopa
    • Facial masking upon presentation
  • 30% with PD may develop dementia
  • Hallucinations and delusions

Dementia with Lewy Bodies:

  • Overlap with Alzheimer’s Disease and Parkinson’s Disease
  • Fluctuations in mental status (may appear delirious)
  • Early delusions and hallucinations
  • Mild extra-pyramidal signs
  • Neuroleptic hypersensitivity!!!
  • Unexplained falls or transient changes in consciousness

Frontal Lobe Dementia:

  • Onset usually 45-65
  • Impairment of executive function
    • Initiation
    • Goal setting
    • Planning
  • Disinhibited behavior
  • Cognitive testing may be normal/minimally abnormal
  • Memory  loss not prominent early feature
  • 5-10% cases of dementia
  • Focal atrophy of frontal and/or anterior temporal lobes
  • Frontal lobe degeneration of the non-AD type (lack of distinctive histopath findings seen with AD or Pick’s)
  • May be autosomal dominant (inherited form known as frontotemporal dementia)

Pick’s Disease:

  • Focal atrophy of frontal and/or anterior temporal lobes
  • Frontal lobe degeneration of the non-AD type (lack of distinctive histopath findings seen with AD or Pick’s)

What laboratory work ups your doctor might request?

Your physician might request the following lab work ups:

  • CBC
  • Electrolytes
  • LFT, Billirubin
  • BUN, Cr
  • Ca, Phophate
  • TSH, T4
  • Vitamin B12
  • Vitamin B1

Is there any diagnostic test that can help with diagnosing dementia?

Brian MRI could be ordered to investigate and to exclude illnesses such as brain tumor and brain cancer that could present with symptoms of dementia. However, currently there is no diagnostic investigation that could be used to confirm diagnosis of dementia.

How is dementia managed?

Drugs to specifically treat Alzheimer’s disease and some other progressive dementias are now available.  Although these drugs do not halt the disease or reverse existing brain damage, they can improve symptoms and slow the progression of the disease. This may improve an individual’s quality of life, ease the burden on caregivers, or delay admission to a nursing home. Many researchers are also examining whether these drugs may be useful for treating other types of dementia.  Many people with dementia, particularly those in the early stages, may benefit from practicing tasks designed to improve performance in specific aspects of cognitive functioning. For example, people can sometimes be taught to use memory aids, such as mnemonics, computerized recall devices, or note taking.

Prevention

The neuroprotective properties of lithium has been demonstrated in clinical studies. Animal studies have found that lithium could improve learning and memory. Also, an observational study suggest that lithium may reduce the risk for dementia in patients with bipolar disorder.

A recent randomized trial showed that daily treatment with low doses of lithium (150 to 600 mg) had stabilizing effects in adults with mild cognitive impairment. Another trial showed that a microdose (300 µg/d) of lithium stabilized cognitive impairment in patients with Alzheimer’s disease.

References

  • Takeshi Terao , Hideki Nakano, Yoshiaki Inoue , Tatsuya Okamoto, Jun Nakamura, Noboru Iwata. Lithium and dementia: A preliminary study. Progress in Neuro-Psychopharmacology & Biological Psychiatry 30 (2006) 1125–1128.
  • Lars Vedel Kessing, Julie Lyng Forman, Per Kragh Andersen. Does lithium protect against dementia?DOI: 10.1111/j.1399-5618.2009.00788.
  • Tobias Gerhard, D. P. Devanand, Cecilia Huang, Stephen Crystal and Mark Olfson. Lithium treatment and risk for dementia in adults with bipolar disorder: population-based cohort study. The British Journal of Psychiatry (2015) 207, 46–51. doi: 10.1192/bjp.bp.114.154047.
error: Content is protected !!