Parkinson’s can cause a condition called Parkinson’s disease dementia. This condition is marked by a decline in thinking, reasoning, and problem-solving.
Parkinson’s disease is a progressive neurological disorder that damages the central nervous system. The condition affects adults primarily older than 65.
Though Parkinson’s disease itself is separated into five stages, Parkinson’s disease dementia isn’t as well understood.
People with Parkinson’s disease typically develop movement difficulties about 10 years before showing signs of dementia, according to the Weill Institute for Neurosciences.
Managing disorientation, confusion, agitation, and impulsivity becomes crucial as dementia worsens in people with Parkinson’s disease. Some people also experience hallucinations or delusions, which can be distressing.
When someone experiences hallucinations or delusions, caregivers can help by focusing on keeping them calm and taking note of their activities before exhibiting these symptoms, and then let their doctor know.
The loss of independence that comes with Parkinson’s disease dementia creates significant challenges for caregivers and those they are caring for. As the condition progresses, many people need constant supervision with daily activities.
Some ways to make caregiving easier include:
- following a routine when possible
- being extra comforting after medical procedures
- limiting distractions
- using curtains, nightlights, and clocks to help follow a consistent sleep schedule
- remembering that the behaviors are a factor of the disease and not the person
The most common symptoms of Parkinson’s disease dementia include:
- changes in appetite
- changes in energy levels
- confusion
- delusions
- paranoid ideas
- hallucinations
- depression
- difficulty with memory recall and forgetfulness
- inability to concentrate
- inability to apply reasoning and judgment
- increased anxiety
- mood changes
- loss of interest
- slurred speech
- sleep disturbances
Lewy body dementia (LBD) and Parkinson’s disease dementia share a common cause: abnormal deposits of a protein called alpha-synuclein that form in the brain. These deposits, known as Lewy bodies, affect thinking and movement.
The timing of symptoms determines which diagnosis a person receives. When thinking problems appear within a year of movement difficulties, doctors diagnose Lewy body dementia.
If dementia develops a year or more after Parkinson’s disease symptoms begin, doctors diagnose Parkinson’s disease dementia.
Both conditions share many features, including rigid muscles and difficulty thinking and reasoning.
These similarities suggest the conditions may be closely related, though researchers are working to understand the connection.
In advanced Parkinson’s disease, people often need intensive support because movement becomes more difficult, and the risk of complications increases. Many need help with walking, use of a wheelchair, or need around-the-clock care.
During this time, they may face higher risks of falls, infections, incontinence, pneumonia, sleep problems, and difficulty swallowing.
Various support services can help maintain quality of life during these challenging stages. These include home health aides for daily care, memory care facilities, and hospice care teams, which provide comfort and medical attention.
Social workers and counselors can also guide families through care decisions and emotional challenges.
Though Parkinson’s disease isn’t fatal, the complications can be.
Research has shown that the age at diagnosis can affect overall survival rates. According to a 2020 population-based cohort study, people with Parkinson’s disease at:
- age 55 had a reduced life expectancy by about 10 years
- age 65 had a reduced life expectancy by about 6 years
- age 75 had a reduced life expectancy by about 3 years
- age 85 had a reduced life expectancy by about 1 year
Though Parkinson’s disease with dementia can shorten life expectancy, many people live for years or even decades after diagnosis when they receive proper care and support.
Diagnosing Parkinson’s disease dementia requires a comprehensive evaluation rather than a single test. A neurologist typically diagnoses Parkinson’s disease dementia first, then monitors changes over time.
Monitoring becomes especially important as people age, because the risk of developing dementia increases.
Your healthcare professional is more likely to conduct regular testing to monitor your cognitive functions, memory recall, and mental health.
Parkinson’s disease gradually destroys brain cells that produce dopamine, a chemical that helps control and coordinate muscle movement. Without enough of this chemical messenger, the nerve cells can’t relay movement instructions to the body, leading to the loss of muscle and coordination.
As the disease spreads through the brain, it can damage areas that control thinking, memory, and judgment.
Over time, the brain may not be able to use these areas as efficiently. As a result, people may begin experiencing symptoms of Parkinson’s disease dementia.
Your risk of developing Parkinson’s disease dementia increases if you experience:
- mild cognitive impairment
- significant movement difficulties
- depression or other mental health changes related to Parkinson’s disease
Though there is no cure for Parkinson’s disease dementia, treatments can help manage its symptoms. Doctors often prescribe cholinesterase inhibitors, such as rivastigmine, to help with thinking and memory problems.
However, some medications can worsen dementia and related mental symptoms. Talk with a healthcare professional to determine the right care and medications for you.
You can keep track of changes in thinking, memory, or behavior by starting a symptom diary. Note when symptoms occur, how long they last, and if medication helped.
If you’re caring for a loved one with Parkinson’s disease, keep a journal for them. Record their symptoms, how often they occur, and any other relevant information.
This information helps your neurologist understand whether these changes relate to Parkinson’s disease, dementia, or another condition.