Alzheimer's disease is a progressive, neurological disorder characterized by a decline in cognitive function that results in dementia (impaired memory, thinking, and reasoning). Alzheimer's disease is the most common cause of memory loss (dementia), affecting approximately 4 million people in the United States. Unless a cure is found the number of persons affected in the US alone could reach 14 million by the year 2050.

In its mild or early stage, Alzheimer's disease (AD) may be overlooked both by individuals developing AD and by those around them. Lack of awareness may be an early AD symptom, although some are keenly aware of diminished memory and thinking abilities. Family and friends may ignore early symptoms hoping they will not progress or because they think nothing can be done to treat AD.

Middle stage or moderate Alzheimer's disease (AD) involves a worsening of the symptoms of early AD, the appearance of new symptoms or both. Obvious impairment of comprehension and judgment often emerge. Dangerous behaviors (e.g., auto accidents if the person is still driving, physical aggressiveness, forgetting to turn off appliances or take medications) make it clear that something is seriously wrong.

The late stage or severe Alzheimer's disease (AD) involves further progression of the signs and symptoms of early and middle stage AD. It is important to search for correctable conditions, especially when a change is sudden. As severity increases, the person with AD can no longer provide self-care, often requiring help with personal activities of daily living such as dressing, eating and going to the bathroom. Memory is very poor or gone altogether.

The choice of a specific medication is something for you and your clinician to decide, based on a number of factors. In general, FDA-approved cholinesterase inhibitors are tried first, and more than one of them may be tried before moving to other classes of medications. How much you benefit and how well you tolerate a medication are important in deciding whether to continue that medication or switch to another medication.

Cholinesterase inhibitors slow the breakdown of acetylcholine, an important neurotransmitter involved in thinking and memory. Alzheimer's disease causes several brain abnormalities. One of them is a progressive decrease in the acetylcholine neurotransmitter (brain messenger) system functioning. It's as though an engine — in this case the brain - is being starved of fuel and not firing all cylinders. Cholinesterase inhibitors increase acetylcholine and permit more neurotransmission.

Keeping a current week's supply in a plastic container divided into daily compartments can help you remember to take your medication on schedule. The rest should be stored in the original prescription containers, away from sources of heat or moisture and out of contact with direct sunlight. Do not store Alzheimer's disease medication in the bathroom medicine cabinet where heat and moisture may cause it to break down.

If cholinesterase inhibitors have a beneficial effect, they should usually be continued long-term. Unfortunately, when effective cholinesterase inhibitors have been discontinued, the underlying Alzheimer's disease appears to have been smoldering along under the cover of the effective medication. Without that effective medication, rapid deterioration often occurs. Benefits of continued cholinesterase inhibitor treatment have been observed for as long as several years in some patients.

No. There is no test for Alzheimer's disease. When the genes that cause Alzheimer's disease are identified, then a test can be devised.

Currently, no medications exist to prevent Alzheimer's disease. Potential risk factors being studied are low levels of education, head injury, and high blood pressure. Recent studies show that higher education levels and a reduced risk of head injury may make Alzheimer's disease less likely.

There are a few very rare cases where Alzheimer's disease does run in families. In these cases there is a direct link between an inherited mutation in one gene and the onset of the disease. These tend to be cases of 'early onset' Alzheimer's disease, which affects those under the age of 65. In these cases, the probability that close family members (brothers, sisters and children) will develop Alzheimer's disease is one in two.

Although there are no drugs that can cure Alzheimer's disease, there are a number of drug treatments that can help some people with Alzheimer's disease. The currently available treatments can slow down the progression of the disease in some cases for periods between 6 and 18 months. The main class of such compounds is the cholinesterase inhibitors. Other kinds of drugs are sometimes useful for controlling some of the symptoms of Alzheimer's disease, such as sleeplessness and agitation.

Not enough is known about the causes of Alzheimer's disease for any specific preventative measures to be recommended. Although Alzheimer's disease is more common with increasing age, the trigger for the characteristic changes that occur in the brain tissue of people with Alzheimer's disease is not known. Even though these brain changes are associated with ageing, these are not a normal part of the ageing process.

Former U.S. President Ronald Reagan courageously disclosed his Alzheimer's disease. As with his previous cancer, he graciously shared his experiences to help other sufferers realize they are not alone, that these diseases can afflict anyone and that treatment is available. In 1995, he and Nancy Reagan joined with the Alzheimer's Association to create the Ronald and Nancy Reagan Research Institute to advance Alzheimer's disease research.

Alzheimer's disease can only be conclusively diagnosed by examining the brain after death in an autopsy to determine the presence of characteristics plaques and tangles in certain brain areas. However, doctors can make a clinical diagnosis of "possible" or "probable" Alzheimer's disease in a living person. Several tools are used to arrive at this diagnosis. These include: a complete medical history and tests that measure memory, problem solving, attention, counting, and language abilities.