11B. Potentially reversible dementias

Dementia (major neurocognitive disorder) is an organic disorder of the brain where the patient experiences a significant decline in cognitive abilities, and these cognitive deficits are severe enough that they interfere with the patient’s ability to function in the daily life.

Mild cognitive impairment is a milder form of cognitive decline than dementia and is, in most cases, a precursor stage to dementia. Like in dementia, there is a decline in cognitive abilities, but unlike in dementia, the patient is still able to perform simple everyday activities.

In patients with dementia, it’s important to look for potentially reversible causes of dementia. These causes can be treated and potentially reverse the patient’s cognitive decline.

Potentially reversible dementias

• Depression (often called pseudodementia)
• Normal-pressure hydrocephalus
• Metabolic disorders
  • Liver failure
  • Kidney failure
• Post-trauma (contusion, subdural haematoma)
• Endocrine disorders
  • Hypothyroidism
  • Hypercalcaemia
  • Hypoglycaemia
• Vitamin deficiencies
• CNS infections and inflammation
  • HSV encephalitis
  • Autoimmune encephalitis
• Alcohol abuse
• Drugs and medications
  • Benzodiazepines

Evaluation

To exclude potentially reversible dementias, there are certain screening tests which should be performed in people with dementia:

• CBC
• Electrolytes
• TSH level
• B12 and folic acid
• Creatinine for kidney failure
• Liver function tests
• Screen for depression and anxiety
• Neuroimaging with native MRI or CT