The Difference Between Alzheimer's Disease and Dementia, Explained
Dementia is often considered a big picture, catch-all term for all types of memory disorders—and most of the time, it is. There are, however, a few specifications that set Alzheimer's disease (a type of dementia) apart from general dementia and other memory loss-inducing conditions. Ahead, a physician explains their overlaps and key differences, and also offers other causes for cognitive decline.
Alzheimer's and dementia are often used interchangeably, but the former is actually a specific type of the latter, explains Dr. Sarah Candler, an Iora Primary Care physical and its care team director. "Consider the relationship between a rectangle and a square: Every square is a rectangle, but not every rectangle is a square," she says. "Similarly, Alzheimer's disease is an example of dementia, but not every type of dementia is Alzheimer's."
Memory and Physical Health
According to Dr. Candler, Alzheimer's disease is the most common type of dementia, accounting for nearly 60 to 80 percent of all forms of dementia that are diagnosed annually. "In most cases, patients who suffer from Alzheimer's initially only experience memory trouble, but are otherwise able to fully function physically until the end stages of the disease," she says. "Other types of dementia, like Parkinson's, lead to significant physical complications that can be present in earlier stages of the disease (even before memory issues really start to arise)."
Overlaps and Outliers
Most dementia disorders are irreversible and progressive, or continue to worsen with time, explains Dr. Candler. "The one exception is vascular dementia, which commonly happens after someone has suffered a stroke. This is when part of the brain has lost blood flow—either from a bleed or a blood clot, causing functions of that part of the brain to stop working," she explains. "In some cases, unlike other dementias, certain symptoms of vascular dementia can be treated and reversed through rehab."
Anxiety and Depression
Dr. Candler often sees patients who express concerns about their memory, but don't have a brain disorder at all. "For example, when we feel depressed, anxious, or overwhelmed, our brain can have challenges paying attention and creating memories," she says. "Sometimes, the issue isn't that a patient is losing their memory, but that their brain wasn't paying enough attention to turn their experiences into memories in the first place." This is why she suggests explaining the totality of your symptoms, including anxiety and depression, to your doctor; doing so will lead to a more accurate, oftentimes treatable diagnosis.
How to Act
If you begin to notice memory trouble, Dr. Candler advises seeking the help of your primary care physician, who will be able to get to the root of your condition. "Patients often think that they are starting to develop dementia, but they're actually experiencing other conditions like anxiety, depression, vitamin deficiency, or thyroid issues, and it's important, and usually reversible, to treat those specifically," she says.