In Alzheimer’s disease, changes to the brain cause dysfunction that results in progressive dementia and other symptoms. Abnormal protein called beta-amyloid builds up to form plaques between brain cells. Brain damage begins in areas responsible for memory and spread through the brain, destroying nerve cells, shrinking brain tissue, and causing worsening symptoms. Dementia is eventually fatal in all cases.
Sundowning is a pattern of worsening symptoms of confusion, agitation, and restlessness beginning in the evening around dusk that lasts through the nighttime hours. Sundowning is common in people with Alzheimer’s.
Medications can help manage many Alzheimer’s symptoms.
Symptoms of Alzheimer’s vary between individuals and between stages of the disease. An individual with Alzheimer’s will usually experience mild symptoms early in the disease course. Alzheimer’s is a progressive disease, which means that symptoms worsen gradually over time, new symptoms appear, and disability accumulates.
Cognitive symptoms are the hallmark of Alzheimer’s, and usually among the first symptoms to appear. Examples of cognitive symptoms include deficits in:
As dementia progresses, people with Alzheimer’s become increasingly confused and less aware of their surroundings.
Many people with Alzheimer’s experience mood changes. Psychological issues may include:
As dementia worsens, people with Alzheimer’s often develop problematic behaviors including:
Psychotic symptoms can include:
In the late stage of Alzheimer’s, severe damage to the brain causes motor (movement) symptoms. At this stage, people begin to need assistance walking or sitting. They may become unable to hold up their head. Some people lose the ability to swallow as they approach death.
For some people, the first symptom of Alzheimer’s may be apraxia – difficulty performing a voluntary action.
Problems with sleep are widespread in people with Alzheimer’s. Sleep patterns may change, with frequent daytime sleeping and nighttime restlessness.
Alzheimer’s can cause problems with visual processing, especially peripheral vision and perception of motion, depth, contrast, or color.
In advanced Alzheimer’s, many people lose the ability to control their bladder and bowels.
People with severe Alzheimer’s are more susceptible to infections, especially pneumonia, skin infections, and urinary tract infections.
Alzheimer’s can cause seizures. Alzheimer’s and related neurodegenerative conditions are thought to cause 10 percent of new epilepsy cases in people age 65 or over.
Alzheimer’s begins differently for each person. Mild memory loss is the most typical initial symptom for those with late-onset Alzheimer’s. Those with early-onset Alzheimer’s may notice apraxia - trouble performing a familiar activity. Others notice visual changes, difficulty solving problems, lapses in reasoning or judgement, problems speaking or writing, or changes in mood. Some people experience multiple symptoms at once.
Learn more about types of Alzheimer’s.
What symptoms lead to a diagnosis of Alzheimer’s?
Dementia is diagnosed based on symptoms including memory loss and deficits in reasoning, judgement, communication, and attention. A more specific diagnosis of Alzheimer’s disease or another type of dementia can take months or years. Before reaching a diagnosis of Alzheimer’s disease, doctors must rule out other conditions that could potentially cause the symptoms. Read more about the process of diagnosing Alzheimer’s.
At what age do most people first experience Alzheimer’s symptoms?
Alzheimer’s is typically diagnosed after age 65, and the likelihood of developing the condition rises with age. Less than 5 percent of Alzheimer’s disease cases are diagnosed before age 65. People as young as their 30s have been diagnosed with Alzheimer’s.