Alzheimer's disease is a form of dementia that impacts thinking, memory, and behavior. Dementia is generally defined as the loss of cognitive skills to the point that it affects a person's daily activities. Forms of dementia occur when once-healthy nerve cells in the brain lose their connections to other brain cells and die. While it's true that everyone loses some level of neurons in their brain as they age, dementias are much more drastic and are not considered a normal part of aging. Severity can range from mild dementia, which can include forgetfulness or difficulty completing complex tasks, to end-stage dementia which has severe symptoms that limit a person's ability to communicate or even control their movements. Naturally, dementia symptoms have a major impact on an individual's quality of life.

Alzheimer's disease is the most common cause of dementia, and it ranks as one of the top 10 most common causes of death in the United States. The greatest risk factor for Alzheimer's is older age, with the majority of those diagnosed at 65 years old or more. Additional risk factors can include family history and changes in the brain. It also seems that risk factors for heart disease, stroke, and high blood pressure may also be related. The disease tends to progress in stages.

Normal Forgetfulness

Even younger adults may experience some level of forgetfulness or temporary cognitive impairment. Older adults are likely to experience some subjective complaints about their cognitive performance, but so long as family members see no cognitive decline and the individuals are free of common agitation, mood swings, and other symptoms associated with Alzheimer's, the individuals are considered mentally healthy.

Mild Cognitive Impairment

At this stage, family members or others close to the individual may notice behavioral symptoms indicative of the onset of dementia. These may include repeating questions, difficulty learning new information, or decreased job performance. A full diagnosis of Alzheimer's is unlikely at this point, but it's still important to seek medical care at this point since symptoms indicate the possibility of early-stage dementia.

Mild Alzheimer's

People at this stage have progressed to the point that they have difficulty managing complicated tasks, and this should be obvious to loved ones and caregivers. At this stage, a diagnosis of Alzheimer's is entirely possible. At the time of diagnosis, Alzheimer's stages life expectancy can range from three years to more than twenty. The rate of cognitive decline depends on the individual, and potential treatments for Alzheimer's include medications that help prevent further destruction of the brain as well as therapies and mental exercises to keep cognitive skills strong.

Memory loss and a decline in emotional responsiveness will be noticeable in this stage, but the individual should be fine with supervision.

Moderate Alzheimer's

At this stage, Alzheimer's patients will begin to have difficulty with the activities of daily living and are likely to require caregivers. Cognitive deficits will become more severe, including the inability to remember recent events. Long term memory may also begin to suffer with the individual only sometimes being able to recall memories from their past. One of the most common symptoms of dementia at this stage is the inability to choose clothing properly.

Severe Alzheimer's Disease

In the later stages of the disease, Alzheimer's patients become unable to perform basic tasks without assistance. Advanced dementia symptoms include the inability to dress without assistance, maintain cleanliness, or adjust bathwater without assistance. Memory loss at this stage also becomes severe, and individuals may even have difficulty recognizing family members. Emotional changes also tend to become the most severe in the late stages of dementia due both to changes in the brain and growing fear and anger about the condition.

Eventually, patients will require around the clock care, such as in a nursing home, and will largely lose the ability to communicate. In the final stage of Alzheimer's disease, patients will become effectively immobile, and patients in this stage become more vulnerable to the majority of causes of death. The most common of these is pneumonia, but some patients reach the end of life due to no discernible cause other than Alzheimer's disease itself.