Dementia is a general term for a decline in mental ability severe enough to interfere with daily life. Memory loss is an example. Alzheimer’s is the most common type of dementia.
Dementia is not a specific disease. It’s an overall term that describes a group of symptoms associated with a decline in memory or other thinking skills severe enough to reduce a person’s ability to perform everyday activities.
Alzheimer’s disease accounts for 60 to 80 percent of cases. Vascular dementia, which occurs after a stroke, is the second most common dementia type. But there are many other conditions that can cause symptoms of dementia, including some that are reversible, such as thyroid problems and vitamin deficiencies.
Dementia is often incorrectly referred to as “senility” or “senile dementia,” which reflects the formerly widespread but incorrect belief that serious mental decline is a normal part of aging.
Signs and symptoms
Dementia affects each person in a different way, depending upon the impact of the disease and the person’s personality before becoming ill. The signs and symptoms linked to dementia can be understood in three stages.
Early stage: the early stage of dementia is often overlooked, because the onset is gradual. Common symptoms include:
- losing track of the time
- becoming lost in familiar places.
Middle stage: as dementia progresses to the middle stage, the signs and symptoms become clearer and more restricting. These include:
- becoming forgetful of recent events and people’s names
- becoming lost at home
- having increasing difficulty with communication
- needing help with personal care
- experiencing behaviour changes, including wandering and repeated questioning.
Late stage: the late stage of dementia is one of near total dependence and inactivity. Memory disturbances are serious and the physical signs and symptoms become more obvious. Symptoms include:
- becoming unaware of the time and place
- having difficulty recognizing relatives and friends
- having an increasing need for assisted self-care
- having difficulty walking
- experiencing behaviour changes that may escalate and include aggression.