Now I’m confused! In the past few months, I’ve been part of two separate research studies in which Positron Emission Tomography (PET) scans to look for amyloid plaques (one of the presumed causes of Alzheimer's) were normal, even though the two scans used different methods of measuring the amyloid.
I also had a PET-glucose scan which ought to document damaged areas in the brain where the cells are not fully functioning. That, too, was normal. In other words, I’ve had three different brain scans, none of which indicated that I had Alzheimer's. I’ve just reviewed the results with my doctor.
What is going on?
One possibility is that I needn’t take the results too seriously. Medical tests are never perfect, and these particular tests have only recently been used to diagnose Alzheimer's. We still don’t know enough about their accuracy to know anything with certainty. But three different tests, using different methods and looking for different mechanisms, are unlikely to be wrong simultaneously. My very rough statistical calculations is that, if I have Alzheimer's, the likelihood that at least one of scans would show something is in the neighborhood of 99.75%
A second possibility is that my symptoms are due to something else. Although Alzheimer's is by far the most usual cause of dementia, there are two other fairly common causes, temporal-frontal dementia (TFD), where the damaged cells are in a specific area of the brain, and Lewy Body dementia (LBD where a protein different from amyloid gums up brain functioning. But I would think that the PET-glucose scan should show problems in each of these diseases, too. Vascular dementia (a series of small strokes) is also fairly common, but the scans, including the CT and MRI, should have ruled that out. Further, according to the doctors, the specific combination of my symptoms doesn’t fit any of the three dementias. And—given the other examinations, blood tests, and CT scans that I’ve had—there are no other reasonable possibilities causing dementia.
My doctor said that he still believes I have Alzheimer's. But he’s certainly puzzled by the negative results. The other possibility, he said, was that I was so early in the disease that both scans were negative. If that’s the case, of course, it’s very good news. But it seems to me highly unlikely. I’ve had symptoms for perhaps five years and serious symptoms for three years. In addition, plaque deposition in Alzheimer's begins at least fifteen years before symptoms appear. Being too early in the disease doesn’t seem to me a reasonable explanation for all the normal tests.
Another (unspoken) possibility is that my symptoms are due to normal aging and that I’m among the “worried well,” a polite way of saying that my more severe symptoms are imaginary. I have a difficult time believing this (although, of course, no one who’s just imagining symptoms is going believe it). The neurologist hasn’t mentioned this possibility, but it has to be on his mind. If it’s all in my imagination, then I’m not sure I’m relieved. I’ve blanked out an entire day, lost my ability to do more complex calculations on a spreadsheet, gotten lost three times, have had to give up my usual writing and teaching, and had other major episodes.
As a part of the NIH study, I’ve been scheduled for a full (4 – 6 hour) neuropsychological exam at the end of the month. When I asked the doctor at NIH to give me the results of the scans before the neuropsych exam, he hesitated. Doctors don’t like to give patients partial results because people can worry or jump to weird conclusions. I reassured him that as a physician I understood the problem. So he gave me the results of the scans, and here I am worrying and jumping to weird conclusions.
I’ll wait for the results of the neuropsych tests.
The specifics of my situation feel unique, but many people with mild cognitive impairment (MCI) find themselves confused and anxious because of the uncertainty involved. I’ve written about some of the issues with MCI in early Alzheimer's before. As I read more deeply, however, it seems that medical thinking about MCI is changing. I’ve assumed that if a mild cognitive impairment is progressing, then it’s really just an early phase on its inevitable way to one of the dementias. And this is certainly true much of the time. But some doctors believe that MCI may be more complicated. In some cases, they believe, it may be a specific diagnosis with its own cause that may stay stable or even improve over time. But details are sketchy.
People now come to medical attention much earlier in the disease process. Unfortunately, the appropriate tests, diagnostic criteria and medical understanding have not kept up. When a person is diagnosed early in the disease, uncertainty is inevitable. This isn’t a question of ignorance or incompetence: It’s just the nature of the disease.
No wonder I’m confused.
Wondering if your normal aging is causing anxiety that of course it must be AD, so you lose your keys twice, etc. You could have had a small stroke causing some cognitive problems, etc. I've taken care of patients with early Pick's disease, lewy body dementia, and an MS dementia. And these were fast disease, within months, you could see real cognitive problems. I think its good news! Even if you are in the very first stages, its proof that you are moving slowly through the early stage. The majority of people I have taken care of went from minor short term memory problems to death in less than 7-10 years. Here's hoping you have something even slower than that, and before it gets really bad, you will be in your 90s. that would be good.ReplyDelete
Just wondering if you are feeling anxiety over new symptoms and the anxiety is part of the problem.
In your list of possible diagnoses, you don't mention vascular dementia. That is what my mother had, and her disease progression matches what you describe, in many ways.ReplyDelete
As her neurologist told my brother and I, it is a good news, bad news diagnosis. If it had been AD, we could expect to experience the pain of her not recognizing us at some point, but by then she would also be no longer cognitively experiencing the loss of her normal life.
On the other hand, with vascular dementia, she would likely be "with" us right up to the end, but also have sufficient awareness to continue grieving the loss of her independence, home life, beloved dogs, etc.
Thank you so much for continuing your narrative. Though my mother is gone now, another close relative is walking the same path and it helps to read your story.
You're right, vascular dementia should have been in the list of other dementia. I've corrected the post. Thanks for pointing it out.Delete
I have read your blog from the beginning but never commented. I don't know anyone close who has had AD, but my grandmother and her mother both did (I never knew them) so of course, my mother and I worry about it.ReplyDelete
I just wanted to say I'm sorry. I'm sure it sounds strange to say "I'm sorry your Alzheimer's test were negative," but that's not what I really mean. I just know that sometimes knowing something is easier than uncertainty, even if what you know is bad. When you begin to adjust to it and come to terms, and then have it change, it creates all kinds of opposing feelings. And then there is the guilt that comes because you aren't simply thrilled!
I wish you peace in your heart as you move forward in this journey.
Thanks. that expresses some of my confusion quite well.Delete
My immediate reaction, after just your first lines, of "I'm sorry" is/was horrible: oh, but I don't want to lose you as a guide. Don't leave me alone.Delete
For that reaction I am really sorry but it seems so important to be honest here.
David, my husband too was diagnosed early. We saw symptoms for two years prior to his diagnosis but the doctors ignored us. He took the mini mental and passed, then went to a neurologist and only missed one. Then we had his hearing checked, it was fine. I thought maybe he couldn't hear me as he didn't remember anything I had previously told him. Then we had a neurophysc exam and he did great in everything but short term memory loss. That was only 10% at that point. They then ordered a PET scan which showed plaque consistent with Early on-set AD. I took him to a specialist in Phila because they still could not be sure and she gave me the option to have genetic test done. That showed that he had EOAD due to APOe4/e4. One from his mom and one from his dad. He has been on both Aricept and Namenda since then and it stabilized his confusion. His short term memory is worse but he is doing pretty well. Have you considered doing a genetic test for AD? At this point they might find they were wrong and it is just a B12 deficiency. That would be a real blessing! Thanks for your blog! RuthReplyDelete
I also have the same (APOe4) gene as your husband, but I have only once copy of the gene (from one not both of my parents), but even that about triples the risk of getting Alzheimer's. It sounds as if both copies of your husband's gene is APOe4, which greatly increases the probability of developing Alzheimer's. Thanks for writing.Delete
Yes, definitely has a double e4. Which gives him a 75% chance of getting it early. With a single e4 you only have a 50% change of getting late onset.Delete
Have you tried the Coconut oil, it was helpful to slow down his progression.
I really can't understand why the PET scan would have showed nothing at all but they do have MRI's now that will definitely confirm it with a special dye I believe. Ruth
According to the information that I have, if you have one APOE-4 gene, you have about twice the chance of developing AD as a person without the gene. If both APO genes are APOE-4, then the risk is about 9 times normal (although this seems to vary in different racial groups. (The site where I got my information is https://www.23andme.com/health/alzheimers/.)Delete
According to the research neurologists I've spoken with, there is no test that is completely diagnostic for AD. The PET scans are relatively new (especially the one for amyloid), and the scientists haven't yet completely worked out the full meaning of a positive or negative test. Certainly the amyloid PET scan usually corroborates AD but not always, so it's still unclear. We're still where science often finds itself: With some answers but no certainty.
Wow. No wonder you are a bit confused. You can well imagine how other mortals react to conflicting diagnoses!! Even with AD, you are still leagues ahead of the rest of us, and we thank you for lighting our paths.ReplyDelete
My husband, Jerry, also has AD. He is completing 40 years of medical practice and training residents. His most important test is the history. His mentor, Dr. Edgar Hull, said that if he could not give a diagnosis after taking the complete history, then it was time to repeat the history.
We have a very dear friend who is a psychiatrist. His wife became alarmed when he ran a red light, and she had him tested. The test said that he had AD. She promptly sold their house, moved David into assisted living (or tried to) and she got his medical license and his driver's license taken away.
Dr. David went back to the neurologist for a repeat test and the neurologist admitted that he had made a mistake in his first reading. He had given them another patient's test results.
A mistake like that ruined Dr. David's reputation, it ruined his marriage and strained relationships with his many children and their stepmother.
Dr. Jerry did not bother to take the tests because he knew that they were inconclusive. Why spend the money, the time and take a needy person's place in the doctor's waiting room and to what end? Jerry KNEW what was going on and he had a very close and personal relationship with our internist, who had been one of Jerry's mentees. (Is that a word?)
He had been aware of his condition for the past five years and he knew that six of his relatives who lived a long life, had AD.
We coped with this in the only way I know.....be open with our friends and family. I have always been too open in the past, and tried to be more introverted. HA! I was born talking! I quit my many musical jobs as accompanist and church organist to stay at home with Jerry. We both are passionate about opera, reading, and television for the first time in our life.
Nevertheless, I was SO grateful to find this blog because it has been my guiding light. We have known David since 1987 when I bought his book, Healing the Wounds. Jerry's nurse called Jerry "Dr. Hilfiker" because their personalities are very similar.
Because I am so scattered, I suspect that this letter is not as concise and on point as it should be. I had a teacher at Tulane who offered to teach me how to communicate better, but somehow, at my age (75)I just keep rolling along.
Thank you one and all. I read the blog first thing in the morning and last thing at night. I am deeply grateful.
I am Gerrygirl, and my husband is Jerryboy!
In medical school (1974)I also heard that 90% of making a diagnosis is the medical history. I assume that -- even with all the modern technology -- that's still true. We'll see: certainly my history is most consistent with AD regardless of the tests.ReplyDelete
The neurologist David's story is truly awful. Fortunately there won't be any such repercussions with me, regardless of the ultimate diagnosis.
you should be pleased that your pet scans and your glucose metabolism tests are negative at this stage since there may be hope that what you have is not alzheimers disease. we both know in medicine that tests sometimes may not be positive early on although from what ive read you should have some amyloid plague formation at your stage.
my mci is much earlier than yours and when i have my amyloid pet scan i expect it to be positive if not then i will feel some relief but know that it might show positive later.
i would enjoy the moment for now.
i enjoy your blog.
Absolutely, I SHOULD be pleased. From any external point of view, this should point to the possibility that I don't have AD. As another reader commented in regard to her own similar situation, "I feel so uprooted" from the conception of self that I've had for now over a year. Of course, that's just another opportunity to get closer to the Buddhist practice of recognizing non-self and non-attachment. So, yes, I should be pleased, but, at a feeling level, I'm not ... yet.Delete
First, thank you so much for this blog. I've been following your journey here, though silently until now.ReplyDelete
My partner's diagnoses have morphed considerably over the years -- from viral encephalitis to OCD to schizophrenia to possible vascular dementia -- and it now seems to have settled on primary progressive MS that acts like traumatic brain injury. Her MS likely had its onset 30+ years ago but had gone untreated, due in part to her anosognosia and also to her MS having been ruled out in favor of encephalitis. Most of the damage is in her prefrontal cortex.
Reaching this latest diagnosis took an LP and consultations with a cognitive neurologist and MS specialist in addition to our regular neurologist. Two years ago my partner underwent three days of neuropsych testing, with scores ranging from the second percentile to perfect. She also has one copy of the APOE e4 variant.
As shattering as a diagnosis is, there is a certain comfort that comes with being able to produce a label -- for educating and sharing with others, finding "in-group" support, and exploring treatment options. From my caregiving perspective, I know what it's like to face and adjust to one diagnosis, only to have to readjust to another. That readjustment, in addition to the disorder itself, has been especially hard on my partner because she has a very low tolerance for uncertainty. But even such readjustment is to a (presumably) known condition.
I understand a bit what it's like to be in diagnosis limbo. For me, one of the blessings of your blog lies in your transcendence of the nomenclature, your focus on basic human experience, and your sense of grace. I am very grateful for your approach and wish you well.
While I agree that 90% of diagnoses is history, not always. Because people are funny medical creatures. My 19 year old granddaughter in nursing school came down with pneumonia--4 times. It went away on ABT, came back when it ended. Because the ABT helped, they continued. until the day they air flighted her to the big city to an infection nurse, because she was really close to death. People diagnosing by lung sounds, wheezes, crackles, etc and an Exray showing diffused dark areas, think Pneumonia. Unless it is histoplasmosis. She finally got the right treatment, then the meds caused her to go crazy with C Diff. Poor girl had to drop out of nursing school in March, and now they say she won't get to go back until she pays off her student loans. We're hoping to prove a medical situation that they will let her continue. She's already an EMT like her Mom. But now she thinks flight nurse would be great. If she doesn't have any lung damage from the histo. So diagnoses don't always work. Usually they do. Take care.ReplyDelete
You say you're due to have the 4-6 hour neuropsychological exam at the end of the month, August I presume. I'm confused that you were diagnosed with Alzheimer's a year ago and they didn't give you the test yet? I thought the neuro exam was one of the first test that they give a person.ReplyDelete
There are a number of different cognitive tests that are ordinarily used to diagnose impairment. I have had several of these, all of which have been positive. This particular set of tests that I will have at the end of the month, however, is far more thorough and is, I think, primarily used for research purposes (as in my case) or in cases when more information about the nature of the impairment is needed.Delete