4th Apr 2023
The answer to this question depends on how long a person has had dementia and what type of dementia they have.
That said, dementia impacts every single person differently, and experiences can vary on a case-by-case basis.
People in the earlier stages of dementia exhibit mild symptoms. Signs of dementia such as short-term memory impairment, difficulty focusing, and confusion about time and place are commonly mistaken as characteristic of aging or heightened stress levels. At this stage, a person may be cognizant they are experiencing these symptoms but unaware that they are dementia-related.
During the latter stages, it is common for a person to be unaware they have dementia.  Typified by a steep cognitive decline, people with late-stage dementia may struggle to communicate, eat, or move independently. This can feel all the more distressing for the person with dementia due to their inability to comprehend they have the disease.
This also poses an extra challenge for caregivers, because if a person is unable to accept that they have dementia, they will not comprehend why they require care and may lash out when offered assistance.
It is important to note that being unaware or unable to understand a disease is different than someone being in denial or willfully stubborn about their situation. In fact, the term anosognosia refers to a patient being unaware of their deficits in neurological and psychiatric functioning. This condition can occur in cases of dementia .
Anosognosia, derived from the Greek word for ‘lack of knowledge of disease’, is a condition caused by neural malfunction that renders a person unable to understand they have a medical condition. 
Studies show that 10% of people with mild dementia have anosognosia, and this increases up to 80% in patients with severe dementia. .
Anosognosia exists on a spectrum with symptoms varying from person to person. A person may sometimes recognize they have a condition and at other times believe nothing is wrong.
If left to their own devices, dementia patients with anosognosia may shun medication due to mistakenly believing they are fine and healthy. They may also suffer frequent falls due to their lack of awareness of their deficits. 
Caring for a loved one with dementia can be emotionally taxing, challenging, and at times frustrating. This is made harder still if they are diagnosed with anosognosia.
Remember that this is a medical condition; they are not consciously acting aggressively, self-destructively, and making poor decisions on purpose. They require your support to make sure they take their medications, attend medical appointments, and get the professional help they require.
Work collaboratively with the person you’re caring for. Allow them to continue to carry out tasks they can do safely. For example, letting them help with laundry or supervising them helping with gardening tasks, can be beneficial. Engage in activities together, such as cooking or baking, and have them participate in small ways. Implementing these measures can lead to a better quality of life for the person who has dementia-related anosognosia.
There is no specific treatment for anosognosia, though studies show vestibular stimulation seems to improve the condition temporarily. . Cognitive therapy, such as motivational enhancement therapy, can help patients better understand and address their deficits going forward. .