The appropriate treatment for dementia will depend on the underlying disease. Below is a list of common brain diseases that may include dementia as a symptom.
Often, early symptoms are especially helpful in distinguishing the different types of dementia from each other.
The most common cause of dementia is Alzheimer’s disease.
Initial symptoms: Early symptoms include short-term memory loss, poor judgment, and difficulty finding the right words.
Prognosis: Average life expectancy of those with Alzheimer’s disease ranges from 3 to 10 years after diagnosis, although some people live up to 20 years, depending on a variety of factors, such as the age of diagnosis.
Progression: Vascular dementia typically has a step-like progression, as opposed to a gradual decline more typical of Alzheimer’s. This means that functioning in vascular dementia may remain stable for quite some time after the initial symptoms until a noticeable decline occurs, and then remain at that next level for an extended period again until the next decline develops.
Prognosis: Prognosis in vascular dementia varies greatly and is related to how much damage there is in the brain and other occurrences of strokes or TIAs.
In Parkinson’s disease dementia, the motor and mobility symptoms are present for at least one year before the cognitive changes develop.
Prognosis: Average life expectancy varies significantly depending on the health of the person and the age at which Parkinson’s developed.
In dementia with Lewy bodies, the brain symptoms develop before the body symptoms, at the same time or less than a year after the body symptoms present.
Progression: Dementia with Lewy bodies can vary quite a bit, even from day to day. However, in general the disease starts slowly and worsens gradually.
Prognosis: Average life expectancy depends on many factors but is estimated to be approximately 5 to 8 years after diagnosis.
Korsakoff syndrome is more of a chronic condition consisting of impaired memory, confabulation (making up stories) and hallucinations.
Progression: If treated right away, it’s possible that Wernicke encephalopathy can be reversed. However, it sometimes is followed by the ongoing symptoms of Korsakoff syndrome.
Prognosis: Average life expectancy in Wernicke-Korsakoff syndrome varies significantly. It ranges from essentially no effect in someone who abstains from alcohol to a dramatically shortened expectancy in others.
Progression: As the disease progresses, memory difficulties develop, along with changes in behavior, physical coordination including walking, and vision. In the later stages, hallucinations and psychosis may develop, and overall functioning, including the ability to swallow and eat, deteriorate.
Prognosis: Average life expectancy is significantly affected, as there is no currently no cure for the disease. Approximately 70 percent of patients die within a year of onset.
Progression: As FTD progresses, communication (both the ability to express and understand), memory, and physical ability decline.
Prognosis: Depending on what type of FTD the person has developed, life expectancy ranges from approximately three to ten years after diagnosis.
Prognosis: Life expectancy in Huntington’s ranges from 10 to 30 years after diagnosis.
Progression: As HIV-associated dementia progresses, physical abilities may also begin to decline. For example, someone may have more difficulty with walking or hand-eye coordination.
Prognosis: Prognosis varies and may depend on the body’s response to treatments such as highly active anti-retroviral therapy (HAART).
Progression: As this condition progresses, the ability to walk and move the body deteriorates. Memory loss and poor attention and concentration develop, and in its late stages, a person often is unable to speak.
Prognosis: After FFI develops, life expectancy is approximately 12 to 18 months, though some only live for a few months and others a few years.
Mixed dementia is often misdiagnosed as a single type of dementia and then discovered either through imaging such as MRIs or in an autopsy after death.
Progression: As mixed dementia progresses, brain functioning declines further, causing difficulty in physical abilities such as activities of daily living as well, as all areas of cognition.
Prognosis: Life expectancy after diagnosis of mixed dementia is not clearly established because diagnosis is sporadic. However, researchers estimate that prognosis may be shorter for mixed dementia than for a single cause of dementia such as Alzheimer’s since additional factors are affecting brain functioning.
Progression: While symptoms from a single concussion are often temporary and resolve with appropriate treatment, chronic traumatic encephalopathy typically develops over time from repeated head injuries and is generally not reversible. Later symptoms include poor decision-making ability, aggression, impaired motor function and inability to communicate effectively.
Prognosis: Life expectancy varies according to the severity of injuries.
Progression: Progression varied depending on treatment. NPH is a condition that causes symptoms of dementia but can sometimes be reversed with prompt treatment.
Prognosis: If NPH responds to treatment, walking is often the first symptom that improves followed by continence and then cognition.
