• Loss of cognitive function with normal sensorium
  • Etiology
    • Stroke
    • Infection (particularly syphilis, AIDS, Creutzfeldt–Jakob)
    • Epilepsy
    • Vitamin deficiency (folate, B12, thiamine, niacin) (MCQ)
    • Normal pressure hydrocephalus (NPH)
    • Neurodegenerative disorders
    • Alzheimer’s disease
    • Parkinson’s disease, Huntington’s disease
    • amyotrophic lateral sclerosis
    • Trauma ,Toxins,Tumors
  • Diagnosis/workup
    • Dementia workup should include CBC, electrolyte panel, B12, folate, rapid plasma reagin (RPR), and head CT.

 Clinical pearls :

  • Dementia
    • Progressive decline of intellectual function.
    • Loss of short-term memory and at least one other cognitive deficit.
    • Deficit severe enough to cause impairment of function.
    • Not delirious. (MCQ)
  • Dementia is an acquired persistent and progressive impairment in intellectual function, with compromise of memory and at least one other cognitive domain,
    • most commonly language impairment
    • apraxia (MCQ)
      • inability to perform motor tasks, such as cutting a loaf of bread, despite intact motor function
    • agnosia (MCQ)
      • inability to recognize objects
    • impaired executive function
      • poor abstraction, mental flexibility, planning, and judgment
  • Alzheimer disease (AD)  accounts for roughly two-thirds of dementia cases (MCQ)
  • vascular dementia (either alone or combined with AD) and dementia with Lewy bodies accounting for much of the rest of cases
  • Depression is a common concomitant of early dementia
  • Dementia can be classified as cortical or subcortical.
    • Cortical dementias (MCQ)
      • arise from a disorder affecting the cerebral cortex, the outer layers of the brain that play a critical role in thinking abilities like memory and language.
      • Alzheimer’s and Creutzfeldt-Jakob disease are two forms of cortical dementia.
      •  People with cortical dementia typically show severe memory loss and aphasia — the inability to recall words and understand language.
    • Subcortical dementias (MCQ)
      • result from dysfunction in the parts of the brain that are beneath the cortex.
      • Usually, the forgetfulness and language difficulties that are characteristic of cortical dementias are not present.
      • Rather, people with subcortical dementias, such as Parkinson’s disease, Huntington’s disease, and AIDS dementia complex, tend to show changes in their speed of thinking and ability to initiate activities.
  • "Subcortical" dementias (eg, the dementia of Parkinson disease, and some cases of vascular dementia) are characterized by (MCQ)
    • psychomotor slowing
    • reduced attention
    • early loss of executive function
    • personality changes.
  • Dementia with Lewy bodies (MCQ)
    • confused with delirium, as fluctuating cognitive impairment is frequently observed.
    • Rigidity and bradykinesia are the primary signs, and tremor is rare.
    • Response to dopaminergic agonist therapy is poor. (MCQ)
    • Complex visual hallucinations—typically of people or animals—may be an early feature that can help distinguish dementia with Lewy bodies from AD. (MCQ)
    • These patients demonstrate a hypersensitivity to neuroleptic therapy, and attempts to treat the hallucinations may lead to marked worsening of extrapyramidal symptoms. (MCQ)
  • Frontotemporal dementias (MCQ)
    • a group of diseases that include Pick disease, dementia associated with amyotrophic lateral sclerosis, and other
    • Patients manifest
      • personality change (euphoria, disinhibition, apathy)
      • compulsive behaviors (often peculiar eating habits or hyperorality).
    • In contrast to AD, visuospatial function is relatively preserved. (MCQ)
    • Dementia in association with motor findings, such as extrapyramidal features or ataxia, may represent a less common disorder (MCQ)
      • progressive supranuclear palsy
      • corticobasal ganglionic degeneration
      • olivopontocerebellar atrophy
  • AD typically presents with early problems in memory and visuospatial abilities
    • becoming lost in familiar surroundings,
    • inability to copy a geometric design on paper(MCQ)
    • yet social graces may be retained despite advanced cognitive decline.
    • Personality changes and behavioral difficulties may develop as the disease progresses. (MCQ)
      • Wandering
      • inappropriate sexual behavior
      • agitation
    • Hallucinations may occur in moderate to severe dementia.
    • End-stage disease is characterized by (MCQ)
      • near-mutism
      • inability to sit up
      • hold up the head
      • track objects with the eyes
      • difficulty with eating and swallowing; weight loss
      • bowel or bladder incontinence;
      • recurrent respiratory or urinary infections.

What’s the Difference Between Alzheimer’s Disease and Dementia?

Dementia Disease Explained

What Is Dementia?
Dementia is caused by a loss of nerve cells in the brain. It is a progressive condition, meaning that it gradually gets worse. This is because when a nerve cell dies it cannot usually be replaced. As more and more cells die the brain starts to shrink. This is known as brain atrophy, which can sometimes be seen in a brain scan of someone in the later stages of dementia.

Identifying the Signs of Dementia

Dementia: Symptoms and Treatment

Common Types of Dementia