What Is Probable Alzheimer And Possible Alzheimer?


Because Alzheimer’s disease is difficult to diagnose, and because it shares symptoms with so many other conditions, doctors use a set group of criteria to determine if a patient is suffering from possible Alzheimer’s disease, probable Alzheimer’s disease, or another kind of dementia altogether. The characteristics doctors use to judge their patients symptoms are laid out by the National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer’s Disease and Related Disorder Association (NINDS-ADRDA).

Physicians diagnose possible Alzheimer’s disease based on a complete patient interview, covering personal and family medical history, combined with the results of any neurological, psychiatric, and lab tests conducted. Doctors are likely to suspect Alzheimer’s disease when a patient complains of a gradual progression of memory deterioration, and when they are unable to find any other condition that could explain the memory loss. Doctors will be looking for disorders such as depression or hypothyroidism, neurological damage caused by stroke, or any medications that may be contributing to the loss of memory. An inability to uncover any contributory illness leads to the determination that Alzheimer’s disease is possible.

Probable Alzheimer’s disease is a step beyond possible Alzheimer’s and means that a doctor is “relatively certain” that a patient has the disease. All the same criteria are met that determine possible Alzheimer’s; however, probable Alzheimer’s patients have continued to show deterioration. They have shown increased loss of memory coupled with the emergence of other impairments – their motor skills may be compromised, and their behavior may have changed. They may be unusually emotional or sometimes delusional. At this stage, patients with probable Alzheimer’s disease will usually have a difficult time with their normal daily routines. A key factor in the determination of probable Alzheimer’s disease is the gradual, yet progressive, nature of the symptoms.

In addition to the progression of neurological symptoms, doctors consider a few other factors in deciding that Alzheimer’s disease is probable. They look for a loss of neurological functioning in at least two specific areas. One should be memory loss; the other can be indicated by increased difficulty in solving problems, problems of perception or some other cognitive ability. These symptoms can be identified though various neurological tests. Patients with probable Alzheimer’s disease generally are between the ages of 40-90, though some patients with Down’s syndrome develop Alzheimer’s in the 30s.

The Alzheimer’s Disease and Related Disorders Association identifies seven stages of Alzheimer’s disease, beginning with a genetic or some other kind of pre-disposition to the disease through to stage seven, which is a loss of speech and muscle control. The continued deterioration of cognitive and neurological ability is indicative of the progressive decline doctors expect to see when diagnosing possible and then probable Alzheimer’s disease.

The length of time Alzheimer’s disease takes to progress from possible to probable, and through the various stages, can vary widely. In some patients, the deterioration can take place over as long as 25 years, and some patients reach stage seven within three years. There is no clear determining factor that can predict the length of time the disease will take to progress. The average amount of time a patient had Alzheimer’s disease is 8 to 10 years.

Doctors use the terms possible and probable when identifying Alzheimer’s disease because there is no one clear test that can make a definite diagnosis. Only after they have ruled out all other possible causes for memory loss and cognitive deterioration do they settle on the diagnosis of Alzheimer’s. The NINDS-ADRDA does identify a further category of definite Alzheimer’s disease, but this is not diagnosed until after death. An autopsy carried out by a histopathologist – a scientist who studies disease patterns in tissue – can verify the evidence of Alzheimer’s disease that can be found on a cellular level. Despite the fact that the diagnosis cannot be confirmed until a patient has passed away, a diagnosis of Alzheimer’s disease by a physician is considered to be 90% accurate.