World Alzheimer's Day 2021: Know Key Differences Between Alzheimer's and Dementia

Do you know the difference between Alzheimer's and Dementia? If not, check out this article to know how these two are different.

Chanchal Sengar
Written by: Chanchal SengarUpdated at: Sep 17, 2021 17:04 IST
World Alzheimer's Day 2021: Know Key Differences Between Alzheimer's and Dementia

Memory is one of the most important thing for human beings. Memory loss makes a person incapable to some extent as he/she fails to remember things. there are various conditions where memory loss is seen and Alzheimer's is one of them. While memory loss is easily understood, people often confuse other diseases that are caused due to cognitive impairment. On World Alzheimer's Day 2021, let us differentiate two of the major diseases namely- Alzheimer's and Dementia. Read on to know more.

Dementia is a syndrome and it causes loss of several overlapping intellectual abilities of the brain along with memory loss. Dementia can occur due to several conditions, the most common of dementia is Alzheimer's disease (50-70%). Dementia, basically a term applied to a group of symptoms that negatively impact memory. When we talk about Alzheimer’s is a progressive disease of the brain that slowly causes impairment in memory and cognitive function. The exact cause is unknown to us and no cure is available.

Difference in Symptoms

Alzheimer's disease 

In Alzheimer's disease, initial symptoms are:

  • lack of initiative
  • lack of interest in work
  • neglect of routine tasks

Then gradually develop forgetfulness in the form of remembering and recalling the name of a person and difficulty in recalling day to day events. The patient may ask the same question repeatedly, having failed to retain the answer.

Also Read: Know The Difference Between Alzheimer’s and Amnesia


  • Making the judgment
  • Performing tasks requiringseveral steps
  • Problem-solving are found difficult
  • Change in personality and mood
  • More commonly depression than agitation
  • Sleep disturbance is quite common along with loss of social interaction
  • Suspiciousness or frank paranoid behavior is quite troublesome
  • The patient may have visuospatial disorientation and may get lost even along habitual routes
  • In advance stage, the patient becomes dependent for day to day activities and ultimately become bedbound
  • Dementia patients may have variable symptoms mentioned above along with other symptoms according to the underlying cause


In Alzheimer's disease, MRI brain shows disproportionate atrophy of hippocampus and enlargement of the temporal horn of lateral ventricle. SPECT (single-photon emission computed tomography) and PET (positron emission tomography) show diminished activity in the medial temporal lobe and parietal association area. Distinctive microscopic changes in the brain in Alzheimer's disease are- neurofibrillary tangles within nerve cells, neurotic plaque (amorphous material scattered throughout the cerebral cortex) and degeneration of neurons in the hippocampus.

Although symptoms of the two conditions may overlap, distinguishing them is important for management and treatment.

(With inputs from Dr. Jaideep Bansal, Director, and Head of Department, Neurology, Fortis Hospital Shalimar Bagh)

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