Alzheimer’s disease and Parkinson’s disease are both neurodegenerative diseases. There are similarities between the two conditions. There are also differences in symptoms, treatment, risk factors, and outlook for people with the conditions.
Neurodegenerative diseases cause progressive damage to cells in the nervous system. The effects of these diseases can impact functions such as a person’s memory, behavior, and movement.
Alzheimer’s disease (AD) and Parkinson’s disease (PD) are two of the
AD is the
People with AD have abnormal accumulations of two proteins in their brains:
- beta-amyloid outside of nerve cells (amyloid plaques)
- tau protein inside of nerve cells (neurofibrillary tangles)
The underlying cause of these changes
PD is a condition where nerve cells in a part of the brain involved in movement become damaged and begin to die, leading to progressively increasing problems with movement.
PD may also lead to nonmotor symptoms and changes in memory, thinking, and behavior.
People with PD have accumulations of the protein alpha-synuclein in their nerve cells called Lewy bodies. It’s believed that Lewy bodies contribute in some way to the damage and death of nerve cells in PD.
There are several similarities between AD and PD. Both are neurogenerative diseases with a gradual onset that typically affect older adults. Additionally, both are characterized by unusual accumulations of protein in the brain.
The symptoms of both AD and PD become worse over time, and there’s no cure for either condition. Treatments focus on managing symptoms and improving quality of life. A combination of drug and nondrug therapies is used.
However, there are important differences between AD and PD. For example, the effects of AD largely impact thinking and memory, although movement symptoms can also happen.
The main symptoms of PD involve movement, although nonmotor symptoms can occur as well. People with PD are also at risk of developing PD dementia, a type of Lewy body dementia.
In addition to what we’ve discussed above, both AD and PD also have specific differences in things such as treatments, risk factors, and outlook for people with the conditions.
We’ll break down each of these topics in more detail below.
The symptoms that someone with AD experiences can depend on how advanced their disease is. General symptoms of AD can include:
- problems with memory
- trouble communicating or finding words
- impaired reasoning or poor judgment
- behavioral or personality changes
- disorientation or confusion
- difficulty with speaking, swallowing, or movement
The symptoms of PD can vary greatly between individuals and also depend on how advanced PD has become. Overall, the main symptoms of PD are:
- muscle stiffness
- slowed movements
- troubles with coordination and balance
People with PD may also have a variety of symptoms that aren’t related to movement. These include:
- muscle cramps
- urinary problems
- sudden drops in blood pressure when standing up
- disrupted sleep
- sexual dysfunction
- reduced sense of smell
- difficulty with speaking or swallowing
There’s no cure for AD. However, there are several drugs that can treat the symptoms of AD. These include drugs such as donepezil (Aricept) and rivastigmine (Exelon), which work by regulating the levels of chemical messengers in the brain.
Other drugs called aducanumab (Aduhelm) and lecanemab (Leqembi) may reduce amyloid plaques in the brain.
Aducanumab and lecanemab to treat Alzheimer’s disease
Both aducanumab and lecanemab were approved by the Food and Drug Administration (FDA) using the
This allows individuals with serious health conditions for which there are limited treatments to have access to potentially beneficial therapies. However, if further trials can’t show a benefit, the FDA can withdraw the drug’s approval.
Sometimes other drugs are also used to treat AD. For example, antipsychotic drugs may be used to manage agitation or aggression in some individuals with AD, whereas certain types of antidepressants can help address depression.
Nondrug treatments can also help people with AD. These include:
- keeping yourself mentally stimulated
- engaging with a therapist or counselor to help cope with the effects of AD
- getting mild to moderate levels of exercise
- eating a healthy, balanced diet such as the MIND diet — this stands for “Mediterranean-dietary approaches to stop hypertension (DASH) intervention for neurodegenerative delay” — or the Mediterranean diet
- developing a support network that can help improve your mental and emotional well-being
As with AD, there’s no cure for PD. Drugs such as levodopa-carbidopa (Sinemet) and others can help address the motor symptoms of PD.
Additional drugs can also be used to manage the nonmotor symptoms of PD. One example is prescribing antidepressants to treat depression associated with PD.
Other types of treatments can also be beneficial for people with PD, including:
- physical and occupational therapy
- speech therapy
- talk therapy such as cognitive behavioral therapy
- regular exercise
- a healthy, balanced diet
- complementary therapies such as massage or yoga
Deep brain stimulation may also be helpful for some people with PD that doesn’t respond well to medications.
The risk factors for AD include:
- older age
- a family history of AD or dementia
- certain genetic variations such as one involving the APOE e4 gene
- Down syndrome
- certain health conditions such as:
- traumatic brain injuries
The risk factors for PD are:
- older age
- male sex
- a family history of PD
- certain genetic variations
- exposures to pesticides
AD is progressive, meaning that it gets worse as time passes. Those in the later stages of AD have problems swallowing. This increases the risk of aspiration pneumonia, one of the most common causes of death in people with AD.
AD was the
PD is also progressive. Generally speaking, it’s difficult to determine how each individual with the condition will progress. While the life expectancy of people with PD is
The effects of PD typically lead to some level of disability
How common are Alzheimer’s disease and Parkinson’s disease?
The Alzheimer’s Association estimates that AD is the cause of 60 to 80% of dementia cases. They also estimate that 6.5 million people ages 65 years and older in the United States are living with AD.
PD is less common. The Parkinson’s Foundation estimates that nearly 1 million people in the United States are living with PD.
Can Alzheimer’s disease or Parkinson’s disease be prevented?
There’s no known way to prevent AD or PD for sure. However, implementing healthy lifestyle habits, such as eating a
AD and PD are two of the most common neurodegenerative diseases. Both are progressive conditions with no known cure. However, treatments can help manage symptoms and boost quality of life.
While AD and PD do have some similarities, they also have several important differences. These can include their predominant symptoms as well as differences in treatments, risk factors, and outlooks for people with the conditions.