What's the Difference Between Alzheimer's and Dementia?

People often refer to dementia and Alzheimer's disease interchangeably, but the two terms aren't synonymous. By learning more about how they differ, you can better understand the challenges associated with them that may be affecting you or a loved one.

The Difference Between Alzheimer's and Dementia

The main difference between Alzheimer's and dementia is that Alzheimer's is a disease, and dementia is not. Instead, it's an umbrella term for a group of symptoms that includes memory loss, a decline in language and comprehension skills, a reduction in judgment skills, and the inability to think through tasks, such as finding your way home from the store, preparing a meal, or getting dressed.

Alzheimer's, on the other hand, is a disease that causes this set of symptoms. Currently, there are more than five million people in the United States who have Alzheimer's disease, and scientists predict that this number will increase to 14 million by 2050.

Alzheimer's and Other Progressive Dementias

Alzheimer's disease is the most common cause of dementia, but it's not the only one. Dementia can also be caused by other diseases, such as frontotemporal lobe dementia, Parkinson's disease, and Huntington's disease. These, along with Alzheimer's, are called progressive dementias because they progress over time and are not curable. Traumatic brain injuries can also cause this kind of dementia. Since Alzheimer's is just one possible cause of dementia, all people with Alzheimer's have dementia, but not all people with dementia have Alzheimer's.

More Types of Dementia

One important distinction to make when it comes to dementia and Alzheimer's is that some types of dementia can be reversed, but dementia caused by Alzheimer's is not one of them. Dementia can also be caused by heavy metal or pesticide poisoning, infections, endocrine imbalances (low blood sugar, thyroid hormone imbalances, or excessive or insufficient sodium or calcium), and even reactions to medications. These types of dementia can be reversible, but progressive dementias are not.

Causes of Progressive Dementia

Although researchers don't completely understand what causes Alzheimer's, they have found that people who have the disease also have clumps of protein in their brain, called plaques. There is also a protein, called tau, which becomes twisted and unable to function properly. Both the plaques and the damaged tau cause cell death, which results in dementia. Parkinson's disease causes a different kind of dementia, brought on by having too much dopamine in the brain. Meanwhile, frontotemporal lobe dementia is caused by the degeneration of the brain cells. This can be caused by accumulation of tau, as with Alzheimer's, or by the accumulation of another protein, called TDP-43.

When dementia is progressive, it usually only begins when the underlying disease has progressed significantly.

Risk Factors for Dementia

Progressive dementias are part of a disease process and can't be prevented, but you may be able to reduce your risk of some other types of dementia by taking these steps:

• Reduce your risk of brain injury. Wear helmets when participating in activities that could result in a head injury. Wear your seat belt when in a motor vehicle. Seek medical help if you do have a head injury or suspect you might have a concussion, particularly if you already had a previous injury.
• Watch for signs and symptoms of infection and seek treatment as soon as possible if you think an infection is present.
• Report any drug side effects to your doctor or pharmacist.
• See your doctor if there's a change in your mental state so you can be evaluated for possible causes.