Alzheimer’s disease is an irreversible brain disease that slowly destroys memory skills, thinking skills and, eventually, the ability to carry out daily activities, leading to the need for full-time care. Dementia is the general term for a group of brain disorders that cause problems with thinking, memory and behavior. Alzheimer’s disease is the most common type. Symptoms vary from person to person, but all people with Alzheimer’s disease have problems with memory loss, disorientation and thinking ability. People with Alzheimer’s disease may have trouble finding the right words to use, recognizing objects (such as a pencil), recognizing family and friends, and may become frustrated, irritable, and agitated. As the disease gets worse over time, physical problems may include loss of strength and balance, and diminishing bladder and bowel control. As more and more of the brain is affected, areas that control basic life functions, like swallowing and breathing, become irreversibly damaged, resulting eventually in death.

Dementia is a group of symptoms that cause a decline in thinking and memory skills severe enough to interfere with a person’s normal daily activities and social relationships. Alzheimer’s disease is the most common cause of dementia in older people. The second most common cause of dementia is multi-infarct dementia, which is caused by a series of strokes. Some of the other diseases that cause dementia are: Creutzfeldt-Jakob disease, normal pressure hydrocephalus, Pick’s disease, Parkinson’s disease, Lewy body disease, and Huntington’s disease. Symptoms of dementia may also result from depression, drug interaction, metabolic disorders (such as thyroid problems), head injury, vision or hearing problems, tumors, and infection. It is important to identify the actual cause, as many of these conditions are reversible. Early diagnosis increases the chances of treating these conditions successfully.

Mild cognitive impairment (MCI) is a borderline condition between normal, age-related memory loss and early Alzheimer’s disease. A person with MCI is characterized as having memory problems beyond that expected for a person’s age, yet without other clinical signs of dementia. Individuals with MCI have a higher than normal chance of developing Alzheimer’s disease.

An estimated 6.2 million Americans of all ages are living with Alzheimer’s disease in 2021.

  • More than 1 in 9 people (11.3%) age 65 and older has Alzheimer’s disease.
  • The percentage of people with Alzheimer’s dementia increases with age: 5.3% of people age 65 to 74, 13.8% of people age 75 to 84, and 34.6% of people age 85 and older have Alzheimer’s dementia.

Yes – the disease can occur in people in their 30s, 40s, and 50s; however, most people diagnosed with Alzheimer’s are older than age 65.

Scientists currently believe that there is not a single cause of Alzheimer’s disease. The disease likely develops from multiple factors, such as genetics, lifestyle and environment. Scientists have identified factors that increase the risk of Alzheimer’s. While some risk factors — age, family history and heredity — can’t be changed, emerging evidence suggests there may be other factors we can influence.

Two types of Alzheimer’s disease exist: familial Alzheimer’s disease (FAD), which is an early-onset form of the disease that appears to be inherited, and sporadic Alzheimer’s disease, where no obvious inheritance pattern is seen. Approximately 5% of Alzheimer’s disease is familial and approximately 95% is sporadic. In familial Alzheimer’s disease, several members of the same generation in a family are often affected. Sporadic Alzheimer’s disease develops as a result of a variety of factors, which scientists are still attempting to determine. Age is the most important known risk factor for sporadic Alzheimer’s disease.

There is no single clinical test that can be used to identify Alzheimer’s disease. A comprehensive patient evaluation includes a complete health history, physical examination, neurological and mental status assessments, and other tests, including analysis of blood and urine, electrocardiogram, and an imaging exam, such as CT or MRI. While this type of evaluation may provide a diagnosis of possible or probable Alzheimer’s disease with up to 90 percent accuracy, absolute confirmation requires examination of brain tissue at autopsy. For information on diagnosing Alzheimer’s disease, visit the Alzheimer’s Association: Diagnosis Information

No treatment is yet available that can stop Alzheimer’s disease. However, the drugs donepezil (Aricept), rivastigmine (Exelon), or galantamine (Reminyl) may help delay the progression of symptoms associated with Alzheimer’s disease. Some behavioral symptoms such as sleeplessness, agitation, wandering, anxiety and depression can be reduced by helping people with Alzheimer’s disease and their family caregivers learn ways to identify triggers for these behaviors and methods to help manage them. Some medicines may help with behavioral symptoms if clinically necessary. For information on the treatment of Alzheimer’s disease, visit the Alzheimer’s Association: Treatment Information