Parkinson’s vs. Alzheimer’s: What Are the Differences?

Parkinson's and Alzheimer's are brain disorders that affect the body's movement, motion, and communication. Though they are similar, there are some key differences.

By James Adisa

Edited by Joel Taylor

Published February 27, 2022.

Both Parkinson's and Alzheimer's are neurodegenerative disorders that are detrimental to your mind and body, but they are not the same. This article looks at the basics of each and their major differences.
What Is Parkinson’s Disease?Parkinson's disease is a neurodegenerative disease diagnosed when a person displays at least two of the following symptoms:
Muscle rigidity
Motor fluctuations
"Shaking palsy"
The symptoms associated with Parkinson's disease result from dead or damaged nerve cells that lead to a decrease in dopamine production. Parkinson's could also disrupt other neurotransmitters that control blood pressure, digestion, and sweating activities.
What Is Alzheimer’s Disease?Alzheimer's disease is a neurodegenerative disorder and the most common type of dementia in older adults. The disease causes agitation and erratic behavior, as well as disruptions in your memory, cognitive skills, personality, and other functions that may lead to brain failure.
In Alzheimer's, tau and beta-amyloid proteins tangle and build up between nerve cells, ultimately disrupting the way nerve cells communicate.
The Main Difference Between Alzheimer's and Parkinson'sThe main difference between the two diseases is that Alzheimer's affects language and memory, while Parkinson's affects cognitive functions (problem-solving) in some people.
Other differences include:
Age of onset
The average age of onset for Alzheimer's is usually 60 years old. However, in some rare cases, it appears before the age of 40. For Parkinson's, most symptoms begin to show up at around 65 years, and, in cases of early-onset, symptoms occur between 50-60

Life expectancy
Both Alzheimer's and Parkinson's are neurodegenerative diseases; however, after a diagnosis of Alzheimer's, the average life expectancy is 4-8 years as a result of the possibility of brain failure. Parkinson's does not generally reduce a person's life expectancy. However, people with Parkinson's are prone to falls and susceptible to infections. 