Updated: May 5
Alzheimer's Disease (AD) is thought to be the most common kind of Dementia. Researchers estimate that as many as 5.4 million people living in the United States have this type of Dementia.¹ Whereas, when you combine all forms of Dementia together, it is estimated to affect 9 million or more people in the U.S.
According to the Centers for Disease Control and Prevention, Alzheimer's Disease is the fifth most frequent cause of death for adults aged 65 years and older.² Further, in high-economic countries³ like the U.S. and Canada, when considering the larger domain - that includes all types of Dementia - Dementia is thought to rank even higher as the third leading cause of death, behind heart disease as number 1 and stroke as number 2.
While it is hard to say what actually causes Alzheimer's Disease, we do know the deposition and accumulation of fibrous proteins accompanies irreversible brain damage. It is thought that these insoluble proteins form β-amyloid plaques that disrupt brain architecture alter how brain cells use energy and promote cell death. The second hallmark of AD, also seen by Dr. Alois Alzheimer over 100 years ago under a microscope, is the neurofibrillary tangles of dead and dying neurons seemingly connected to Tau, another type of protein. That's why medical professionals will often speak of the "plaques and tangles" of AD.
The result is a slow and progressive decline in memory, thinking, and reasoning skills. Eventually, people lose the ability to swallow and breathe in a coordinated fashion. Even in the absence of other catastrophic diseases such as kidney failure and cancer, Alzheimer's Disease is a terminal illness.
Alzheimer's Disease comprises a spectrum rather than a defined set of signs and symptoms. Slow progression, rather than a sudden change, is often the key to differentiating Alzheimer's behaviors from those associated with other kinds of Dementia. Life expectancy after an Alzheimer's diagnosis can be anywhere from four to 20 years. People who have Dementia often die from other causes such as cancer, kidney failure, and cardiovascular disease.
The Alzheimer's Association lists the 10 warning signs of Alzheimer's Disease – the first of which is memory loss. After reading the list you might think, How are these behaviors different from what everybody does at one time or another? The difference is the frequency and the ability to make self-corrections.
Healthcare providers often use staging to describe the progression and severity of diseases such as cancer, kidney failure, and Dementia. The following staging criteria will help you understand your loved one’s condition and plan for future caregiving needs.
Mild or Early-stage Alzheimer's Disease
In this first stage, people experience memory loss, difficulty remembering newly learned information, and have trouble completing complex tasks such as planning a family event. Personality changes such as uncharacteristic anger and increasing difficulty in finding the right words, getting lost, or misplacing items are other common signs. With help, your parent, spouse, or sibling may still be capable of independent living.
Moderate or Mid-stage Alzheimer's Disease
During this phase, people may confuse family members with close friends, forget personal history details such as where they went to school or where they were born, and need help with dressing and personal hygiene. Some people may become restless, suspicious of others, and confrontational. At this stage, your relative will need close supervision and assistance during the day and perhaps a caregiver during the night.
Severe or Late-stage Alzheimer's Disease
In the course of this last stage, people who have Dementia lose the ability to speak coherently, need help with eating, dressing, using the bathroom, and walking. Eventually, Late-stage Alzheimer's patients lose the ability to swallow and control their bladder and bowels. During this final stage, your loved one will need 24-hour care, either at home or in a Dementia care facility.
1. 2017 Facts and Figures: Alzheimer’s Disease Facts and Figures, Download source here: 2017 Alzheimer’s Disease Facts and Figures. (accessed September 18, 2017).
3. 2017 World Health Organization Factsheet Download source here: 2017 World Health Organization Factsheet.
Content Contributor: Janet Yagoda Shagam, Ph.D., is a freelance medical and science writer and the author of "An Unintended Journey: A Caregiver's Guide to Dementia.", available through Amazon. Please visit our Author's page to learn more and find this title.
The opinions expressed by contributing authors are not necessarily the opinions of the Dementia Society, Inc. We do not endorse nor guarantee products, comments, suggestions, links, or other forms of the content contained within blog posts that have been provided to us with permission, or otherwise. Dementia Society does not provide medical advice. Please consult your doctor.