Written by Dr. Martha Leatherman, PPL Medical Advisory Board   

OldWoman 36921294 MAlzheimer's disease is one disease among many known as the dementias. Strictly speaking, dementia is a very general term that describes changes in brain function marked by changes in behavior and thinking (cognition). There are many different causes for the changes in the brain which cause dementia, and with a very few exceptions, they are irreversible.

While there are over 50 different kinds of dementia, common to all these different forms of dementia, including Alzheimer's, is the fact that brain cells (neurons) are damaged. These damaged neurons disrupt the normal way the brain functions and when the brain can't do its job, the afflicted person will experience cognitive (i.e. thinking), behavioral, emotional or movement problems—and often a combination of all of these.

The most common form of dementia is Alzheimer's disease, which was first described and characterized in 1906 by Dr. Alois Alzheimer and his colleague Dr. Emile Kraeplin. In the past, it was the rule that Alzheimer's was only formally diagnosed by brain biopsy or autopsy. Now, thanks to new technology, a better understanding of the disease, and especially because we have medications that can help slow its progression, we usually make the diagnosis of Alzheimer's disease clinically which just means that we look at a person's symptoms, make sure the symptoms are not due to other identifiable causes, and then, based on the symptom pattern we see, make a diagnosis. This process of clinical diagnosis sounds simple and straightforward. However, although it may be simple, it's far from easy since symptoms of Alzheimer's disease are similar to those of many other forms of dementia, as well as medication complications and other illnesses, but can usually be distinguished by a skilled clinician using careful physical, neurological, and neuropsychological examination techniques.

Alzheimer's specialists can accurately diagnose Alzheimer's disease about 90% of the time. A number of other illnesses can mimic the symptoms of Alzheimer's, and so it's important to use a physical examination, laboratory, and imaging studies to rule out or exclude other treatable causes of the symptoms of dementia. Some of these conditions include depression, dehydration, hypothyroidism (or "low thyroid"), B12 deficiency, syphilis, urinary tract infection, or low sodium in the blood. The diagnostic process includes a complete medical history, examination, and laboratory testing. The medical history should include questions about family history, psychiatric problems or symptoms, physical complaints, all the medications a person is taking, habits such as alcohol or drug use, and memory symptoms. Usually, in order to make sure the medical history is as accurate as possible, a physician will enlist the aid of a family member or spouse. Because brain tumors and strokes can cause symptoms similar to Alzheimer's, some form of brain imaging such as CT or MRI is often necessary when making the diagnosis of dementia.

Neuropsychological testing might be recommended in which a specialized psychologist with expert understanding of brain function as well as human behavior will administer an extensive series of mental tests designed to identify and characterize changes in memory, judgment, insight, and planning. Some physicians, particularly geriatric psychiatrists and certain neurologists might not routinely use full neuropsychological testing, but regardless of who is doing the examination, any patient with suspected Alzheimer's should undergo a careful clinical examination of thinking or mental status examination. Sometimes, in the hands of a skilled physician, patients and families might not even notice that the majority of the mental status examination is taking place because the physician is able to weave the examination questions into conversation. Sometimes physicians are criticized by patients and families who don't understand this and the physician is perceived as "just talking and joking" with the patient. In reality, that "talking and joking" is the mark of a sophisticated clinician.

Although it is tempting to look at a list of symptoms associated with Alzheimer's and try to "diagnose" yourself, and although lists of warning signs to be aware of exist, the diagnosis of Alzheimer's is simply not possible to make using a check-off list. It is important to have an examination by a qualified physician. Even if the diagnosis is made, a person with dementia--even Alzheimer's--can live a meaningful and dignified life.

Though our outward humanity is in decay, yet day by day we are inwardly renewed. . . . For we know that if the earthly frame that houses us today should be demolished, we possess a building that God has provided. . . . we groan indeed, we who are enclosed within this earthly frame; we are oppressed because we do not want to have the old body stripped off. Rather our desire is to have the new body put on over it, so that our mortal part may be absorbed into life immortal. God himself has shaped us for this very end. (2 Cor. 4:16-5:10)