Alzheimer’s Disease
Alzheimer’s disease (AD) is a type of dementia where brain cells die. The condition affects memory, thinking, and behavior. According to the Alzheimer’s Association, this disease accounts for 60 to 80 percent of dementia cases. Alzheimer’s disease is more common in people over the age of 65, but some have early-onset AD and show symptoms as early as their 40s or 50s.
AD is a progressive disease that worsens over time. It’s the sixth leading cause of death in the United States. After a diagnosis, people with the condition can live an average of four to 20 years.
Recognizing early symptoms of AD and intervening helps prolong and improve your quality of life.
Early symptoms of AD
Early AD symptoms can be mild and subtle — so subtle that you may not notice a change in your thinking or behavior. In the early stage of the disease, you’ll likely have trouble remembering new information. This is because the disease often begins to impact areas of the brain responsible for learning new information. You may repeat questions over and over, forget conversations or important appointments, or misplace objects such as your car keys.
Occasional memory loss can be a normal part of aging, so forgetfulness isn’t necessarily a sign of AD. However, you should speak to your doctor if the problem worsens.
The top 10 warning signs include:
misplacing objects and being unable to retrace steps
memory loss that affects everyday life (unable to budget, drive to a location)
difficulty planning or problem-solving
taking longer to accomplish routine daily tasks
losing track of time
having trouble determining distance and distinguishing colors
difficulty following a conversation
poor judgment leading to bad decisions
withdrawal from social activities
mood and personality changes and increased anxiety
Moderate symptoms of AD
Eventually, AD spreads to more regions of the brain. Family and friends may recognize changes in your thinking and behavior before you do. Sometimes, it’s hard to identify memory problems in ourselves. But as the disease progresses, you may recognize telltale symptoms in yourself, such as confusion and a shorter attention span. As more of your brain cells die, you’ll begin to show signs of moderate AD, which include:
problems recognizing friends and family members
difficulty with language and problems with reading, writing or working with numbers
difficulty organizing thoughts and thinking logically
inability to learn new tasks or to cope with new or unexpected situations
inappropriate outbursts of anger
perceptual-motor problems, such as trouble getting out of a chair or setting the table
repetitive statements or movement, and occasional muscle twitches
hallucinations, delusions, suspiciousness or paranoia, and irritability
loss of impulse control, such as undressing at inappropriate times or places or using vulgar language
exacerbation of behavioral symptoms, such as restlessness, agitation, anxiety, tearfulness, and wandering — especially in the late afternoon or evening — called “sundowning”
Severe AD symptoms
At this point in the disease, brain plaques (clusters of protein that destroy brain cells) and tangles (dying nerve cells that twist around one another) may appear on imaging tests of the brain. Both are hallmarks of AD. This is the final stage of AD. People at this stage lose control of physical functions and depend on others for care. They sleep more often and are unable to communicate or recognize loved ones.
Other symptoms of severe AD include:
lack of bladder and bowel control
weight loss
seizures
skin infections
groaning, moaning, or grunting
difficulty swallowing
Due to the loss of physical function, people with late-stage AD may deal with complications. Difficulty swallowing can result in inhaling liquids into the lungs, which increases the risk of pneumonia. They may also suffer from malnutrition and dehydration. Limited mobility also increases the risk of bedsores.
Conditions with similar symptoms
There are other causes of dementia with symptoms similar to AD. A doctor conducts physical and neurological examinations and uses brain imaging technology to diagnose or rule out AD. The following list of neurodegenerative diseases can mimic AD:
Parkinson’s disease with dementia leads to shaking and difficulty with walking, movement, and coordination.
Vascular dementia occurs from impaired blood flow to the brain and leads to problems with reasoning, planning, judgment, and memory.
Frontotemporal lobar degeneration affects the brain's frontal and temporal lobes, which are associated with personality, behavior, and language.
Frontotemporal dementia affects the temporal and frontal lobes that influence decision-making, behavioral control, emotion, and language.
Pick’s disease is a rare and permanent form of dementia similar to AD, except it often affects only certain brain areas.
Supranuclear palsy is a rare brain disorder that causes severe and progressive problems with control of gait and balance, complex eye movement, and thinking problems.
Corticobasal degeneration occurs when areas of your brain shrink and nerve cells die over time. The result is growing difficulty moving on one or both sides of your body.
Other possible causes of dementia include:
medication side effects
depression
vitamin B-12 deficiency
chronic alcoholism
certain tumors or infections of the brain
blood clots in or on the brain
metabolic imbalances, including thyroid, kidney, and liver disorders
Outlook
Talk to a doctor if you or a loved one is experiencing symptoms of AD. Because symptoms worsen over time, it’s essential to recognize the possibility of AD. Your doctor can make a diagnosis and assess whether symptoms are mild, moderate, or severe.