About Dementia
About Dementia

Dementia is not a natural part of ageing.  It is a degenerative brain disease characterized by progressive deterioration of cognitive ability, resulting in memory loss, deterioration of ability to handle complicated tasks and even loss of physical abilities in the late stage of the disease, these are the reasons for the people living with dementia to lose their way homes, having fluctuating emotions and poor verbal expression.


Perceiving the symptoms of dementia as the normal part of ageing leading to delayed diagnosis and treatment.  The assumption of dementia will only affect elders is another common misconception about dementia.  Although most people living with dementia are over the age of 65, few of them are under 65 and classified as the early onset of dementia.


Different types of dementia affect different parts of the brain in various degrees and it may also affect different people in different ways even though they are with the same disease, as the impacts of the disease depend upon the person’s personality, living environment and caring style of their caregivers.  So we have to put ourselves in their place in order to understand how they are being affected and what kinds of support they and their families need.

Causes and Types

Alzheimer’s Disease is the most common cause of dementia.


Type Degenerative process Major symptoms Causes
Alzheimer’s Disease Progressive Deterioration in brain functions, including memory (especially short-term memory), judgment, decision-making and executive abilities, and possible impact on self-care ability, behaviours and emotions Unknown; however, researchers have found that presence of abnormal amyloid plaque and neurofibrillary tangles in Alzheimer’s brain tissues lead to rapid degradation and death of brain cells

Vascular Dementia

“Stepwise” deterioration in cognitive abilities may occur with recurrent strokes Depending on which parts of the brain are affected; may overlap with those of Alzheimer’s disease Accumulated brain damage caused by multiple strokes or vascular diseases

Dementia with Lewy Bodies

Unstable, changeable and unpredictable Parkinson’s-like symptoms, including tremor, muscle rigidity, unsteady walking and vulnerability to falls; some may act out their dreams while some have visual hallucinations Abnormal development of Lewy bodies inside the brain that lead to cell death

Frontotemporal Dementia

Onset in one’s forties to sixties usually; unstable, changeable and unpredictable Declines in personality, behaviours (usually disinhibition) and speech occur earlier and more significantly than memory loss Shrinkage of the frontal and temporal lobes, causing progressive brain degradation

Other causes include brain injury, brain tumor, hydrocephalus, viral infection, vitamin deficiency, hormonal imbalance, emotional disorder such as anxiety and depression, drug poisoning, and alcoholism.

Symptoms of Different Stages of Dementia

Dementia is a degenerative disease which progresses in three general stages – early-stage, middle-stage and late-stage. The symptoms change over the disease progression and affect different people in different ways, here’s the overview of common disease progression:


If you are worried about getting dementia, please contact Hong Kong Alzheimer’s Disease Association to arrange Early Detection Service or consult your physician.
Service Enquiry: 2338 1120