BACKGROUND: Alzheimer’s is the most common type of dementia that can cause problems with thinking, memory, and behavior. Fifty to eighty percent of dementia cases are patients with Alzheimer’s. The disease progressively gets worse, interfering with daily tasks. The disease is fatal and there is currently not a known cure. Although Alzheimer’s mostly affects people 65 and older, it is not just a disease of old age. Close to four percent (or 200,000) of Americans, with the disease have early onset, also known as younger-onset, which appears when they are in their 40s or 50s. In the early stages of Alzheimer’s, memory loss is mild. However, as the disease progresses it can cause a person to lose their ability to respond to their surroundings and lose their ability to carry on a conversation. Alzheimer’s is the sixth leading cause of death in the United States. On average, people live eight years after their symptoms are noticeable to others. However, survival can range from four to 20 years depending on age and other health concerns. (Source: www.alz.org)
7 STAGES OF ALZHEIMER’S: Not everyone will experience the same symptoms or progress at the same rate. However, Barry Reisberg, MD, clinical director of the New York University School of Medicine’s Silberstein Aging and Dementia Research Center, created a 7 stage framework for the disease:
· Stage 1: No impairment. The person does not have any memory problems
· Stage 2: Very mild cognitive decline. Person may feel as if they have memory lapses, but can’t be detected by an exam.
· Stage 3: Mild Cognitive decline. Family, friends, and co-workers begin to notice difficulties like remembering names, the right word, losing valuable objects, trouble organizing, etc.
· Stage 4: Moderate Cognitive decline (early-stage Alzheimer’s). Medical interview should be able to detect it. Symptoms include: forgetfulness of recent events, impaired ability to perform challenging mental arithmetic, forgetfulness about one’s own personal history, moody, and greater difficulty performing daily tasks.
· Stage 5: Moderately severe cognitive decline. Gaps in memory and thinking are noticeable and they begin to need help with day-to-day activities. At this stage, they will not be able to recall their own address; they are confused about what day it is; and they need help choosing clothes.
· Stage 6: Severe cognitive decline. Memory continues to get worse, personality changes get worse, and they need extensive help with daily activities.
· Stage 7: Very severe cognitive decline. They lose the ability to respond to their environment, to carry on a conversation, and eventually to control movement. (Source: www.alz.org)
NEW TECHNOLOGY: An important aspect of treatment is early detection. The FDA approved a new technology to detect Alzheimer’s, called Amyvid. Its radioactive dye is used with positron emission tomography (PET) to visualize amyloid plaque buildup in the brain. It’s designed to be used on adult patients with cognitive impairment. A negative Amyvid scan shows scarce plaques and is inconsistent with a neuropathological diagnosis of Alzheimer’s. It also reduces the likelihood that a patient’s cognitive impairment is caused by Alzheimer’s. A positive Amyvid scan indicates moderate to frequent amyloid neuritic plaques; neuropathological examination has shown this amount of amyloid neuritic plaque is present in patients with the disease, but may also be present in patients with other types of neurologic conditions along with older people with normal cognition. In other words, if a patient with dementia does not have amyloid buildup, then the cause of dementia is likely not to be Alzheimer’s. If the scan shows they do have amyloid buildup, their chances of having Alzheimer’s increased. A positive scan does not establish a diagnosis of Alzheimer’s, just increases their likelihood. More research is needed to understand the appropriate use of florbetapir-PET imaging in Alzheimer’s diagnosis. The FDA approval of Amyvid will expand the clinical and research opportunities for amyloid imaging. The Alzheimer's Association has convened a task force with the Society of Nuclear Medicine to develop recommendations for the use of amyloid imaging for physicians, imaging and other medical specialists, Alzheimer families and the general public. (Source: www.alz.org)
Dr. Paul Schulz, Neurologist at Mischer Neuroscience Institute at Memorial Hermann-Texas Medical Center, talks about a new way to diagnose Alzheimer’s.
What is the only way that Alzheimer’s can be definitively diagnosed?
Dr. Schulz: The only way to definitively diagnose it in the past was with a biopsy or if someone passed away and you got a chance to examine their brain at autopsy. We were giving it our best guess as to what they have based on their symptoms and testing them, but we were never really certain about what they had.
What were you looking for in a patient’s brain after they passed that would prove they had Alzheimer’s?
Dr. Schulz: There’s a protein that’s deposited in their brain called amyloid and we only see significant amounts of it in people who have the disease. The amyloid that is deposited is the key. We would do stains on sections of their brain and we would look at the amount of amyloid that had been deposited in their brain. That would tell us that they had Alzheimer’s disease versus any of the other dementias that can look very similar clinically.
Is it high levels of amyloid that signifies that?
Dr. Schulz: Yes, we have criteria. It turns out many people have a little bit of it. It’s a byproduct of various reactions, but if you have a significant amount of it then that’s pretty specific for Alzheimer’s disease.
If that’s the only way to make a definitive diagnosis, how would you make a clinical diagnosis?
Dr. Schulz: Typically people would come in to clinic and say, gosh I’m concerned about my memory, I’m getting lost, or I’m having word finding issues. If they are having memory problems, though, a lot of times a person is not aware of it themselves, so often times family members bring them in. I examine them and I give them things to remember. I ask them to draw things, describe how they get home from where we are, and try to understand whether they have significant issues that might be a sign of Alzheimer’s disease. Then we would typically do some blood work to rule out things that can cause memory problems, like thyroid disease. We would do an MRI scan to rule out strokes, tumors, and abscesses. If we ruled out those things then we would be left with saying, well it’s probably Alzheimer’s disease or one of the other neurodegenerative diseases that looks like it.
So it was kind of a guessing game to some degree?
Dr. Schulz: Yes. I think that we all have had patients that we were certain had Alzheimer’s or pretty certain didn’t have it. But when they would come to autopsy, we would be surprised to find out about five percent of the time we were not in the right area at all. Also you could imagine from a research point of view that we enter people in clinical trials, and if it turns out that someone doesn’t have Alzheimer’s, then it wouldn’t be surprising that a medication wouldn’t work. So in retrospect I’m thinking that some of the patients whom we enrolled, that we thought had Alzheimer’s, might not have and it might have confused our clinical trials in the past.
So now there’s a new tool that was just approved in June?