Tuesday, December 04, 2007
Here's the diagnostic secret about dementia: It's all about faking it. It's about faking your way through life until you don't have enough sense of self left to fake it any more.
The standard medical joke about dementia is, if a patient comes to you concerned about memory loss, they don't have a problem with it. As with most medical jokes there is a hard core of truth to this; in dementia, the very nature of the disease process means that patients will not notice that they have a problem. It's their friends and relatives who see it, long before they do. Also, interestingly enough, I feel in nearly every case of dementia that I've seen that there is a strong element of denial to this disease: if a patient senses that he or she is losing their grip on reality they will fight like hell to maintain what they have left, denying that there is a problem. It's like the old cliche, "If you can admit that other people think you might be crazy, you're not crazy." It is also because for some reason the social niceties are preserved until a late stage in the disease. It's possible to meet someone who is properly dressed, polite, and can carry on some sort of light social conversation and not realize that they are moderately demented.
The first real case of advanced Alzheimer's I ever saw was as a medical student: it was in an elderly gentleman who had been admitted for some sort of internal medicine issue. However, the primary MD suspected that dementia was a contributing factor (I can't remember why now) and so my resident did a mini mental status exam, aka MMSE, on the patient in the hospital room.
This was a well-groomed, mild-mannered, well-spoken man - a former college professor - wearing what looked more like a smoking jacket than a bathrobe, some sort of brocade thing. His wife was sitting by his side. It really hit me that something was wrong when my resident picked a pen out of the pocket of his white coat, held it up and asked, "What is this?"
"Well, it's some sort of... object..." the patient confabulated.
He didn't know what a ballpoint pen was. This man, a teacher, could not recognize a pen when he saw one. At the same moment this realization hit me, it hit his wife as well; she started to weep.
Today I had the same sort of oh, shit feeling in my gut. A patient of mine whom I had not seen in over a year came in for a follow up of her COPD (emphysema) and weight loss - she had not been eating well and had lost twenty pounds in the preceding 17 months. (I don't think she has cancer, I think she just isn't eating.) Partway through the visit her watchful daughter raised the issue of memory loss. I didn't have time to do the full MMSE but knew I could interpose a few questions in the course of the exam.
"What year is this?" I asked.
...long, blank pause... OH SHIT I thought, feeling my heart sink. She was able to name the month and season, and the day of the week, but not the date or the year.
Then I asked her to remember three words and repeat them back to me. This is a test for short-term memory. The three words I always use are honesty, tree and chocolate. There is nothing magic about these words; I use them because they are not related to each other (i.e., no two are food items, character traits or plants) and because a neurologist once told me that one of the three words I use should always be something intangible. "If one of the words is something they can't visualize, that's the one they'll forget first if something is wrong," he said. I have no data or study results to know if this is correct, but ever since that day one of the words in my MMSE test has been some sort of intangible personality trait.
At any rate, she was able to repeat the words back to me immediately, but when I returned to the subject a few minutes later she was unable to repeat any of the three words (this after I had explained to her that I would ask her again in a few minutes what the words were).
OOoookay, we have a problem, I thought, realizing that the patient's daughter was weeping just like the other patient's spouse of long ago. Given this patient's weight loss, withdrawal and malnutrition, however, there were any number of other explanations for her symptoms: depression (I think somewhat unlikely, but possible), paradoxical hyperthyroidism, hypothyroidism, diabetes, B12 and/or folate deficiency, subacute syphilis (the most unlikely of all, but we still test for it). I explained all this to the daughter.
The tests are cooking as we speak. I await the results.
Oh, and what do you do for the "worried well" patient who is convinced that they have a memory problem? I once asked a neurologist this and have used her advice ever since.
Give the patient a MMSE exam, show them their perfect results. Reassure them that they do not have dementia. Repeat as needed (and you can throw in a B12 and TSH just for the hell of it).