Thursday, July 31, 2014

The Depression/Dementia Conundrum

Medical science, or more properly,  the medical specialty of neurology/psychiatry, has its own version of, "Which came first, the chicken or the egg?"  Of course, neurologists and psychiatrists really don't deal with chickens, do they?  They do deal with people in various stages of physical and/or mental health. The riddle part comes into the equation when you ask the question, "Does depression cause dementia or is it dementia that causes depression?"

It's a riddle that has long been testing the creativity of researchers to tease out which may come first or do they come together?  Who said there has to be a cause-and-effect relationship here?  I don't think anyone did, but it seems like many people are thinking one must be the cause of the other. Well, it really doesn't work that way because Mother Nature is always outdoing us in her creativity.

A new study has recently come out from a prestigious research facility and they were looking at this very question in a study with an average age of 77 for the participants.  The number of people in the study was not small and this is important, too.  Over 1700 people participated and this would make the results pretty interesting to anyone who is looking at any research work.

This particular study, as many studies in the Alzheimer's area, evaluated patients over time and at each session they looked at whether or not there were symptoms of depression and they also did a series of tests to evaluate the subject's ability to think and to use their memory.  The study actually went on for eight years and this is also significant because it provides us with baseline information and allows us to make some interesting observations.  In other words, were there declines in persons who were depressed?  Or, on the other hand, was there increasing depression in persons who had a degree of dementia?

The study was actually brought to my attention by someone I had interviewed for a book I did a few years ago and he is always a wonderful source of things that make me think and remember certain things that have happened in my professional life.  I say my professional life because, when I see anything that mentions dementia, I am immediately brought back to a time when I worked in a national protocol on Alzheimer's disease.  It wasn't that long ago, yet it was ages ago in terms of what has happened in neurobiology since then even though we still don't have a truly workable medication or treatment for Alzheimer's.  We know a lot, but we don't know enough.

One of the things I vividly recall during that time was the incredible assumption on the part of so many people in major research centers all over the country that anyone who had Alzheimer's needn't be treated for depression.  I found this totally mind blowing.  How could you not treat someone for depression when the very fact that they were losing the person that they were was causing them such mental pain?  It was tantamount to doing surgery without anesthesia in my mind.  And BTW, some people actually used to think that anyone with schizophrenia couldn't feel pain and didn't need anesthesia for some surgical procedures. Yes, truly. Totally absurd and totally without any basis in medicine, psychiatry or psychology.  I brought the topic up whenever it was appropriate, but it was always brushed aside at that time.

A brief review on depression might be helpful here.   I'm sure you are well aware of depression and how it usually manifests itself, but you may not be aware of how depression can affect scores on memory scales in research.  This sounds terribly parochial but it didn't seem to occur to the researchers that the scores they were trying to gather might be depressed scales as a result of the patient's depression.  How can you get a valid score on memory from someone who is depressed because you know that depression can cause problems in attention and concentration?  So what is it? Are you truly testing memory or are you absolutely allowing yourself to remain blind to the fact that depression is entering into this in a very important way?  I leave it to you in your sagacity to figure this one out.

Back to the researchers of this latest matchup of depression and dementia.  Tantalizingly, there appeared to be some sort of relationship between the two since 18 percent of the people in the study developed dementia.  The researchers must have been beside themselves and jumping up and down when they saw that one.  As it happened, 680 people died during the study.  And 582 of them had agreed to brain autopsies which showed that there were scores showing high levels of depression prior to the onset of dementia.  But, and here's the rub, they also found that as people became more demented they became less depressed.  If that didn't throw them for a loop, I don't know what would. I'm sure it has caused them to begin to formulate new studies to explore this possible connection in a number of different ways.

Brain biology is pretty fascinating and it doesn't have to be something to dismiss as boring or too difficult for you to understand.  Please, understand that I am not putting you down, I am just laying a bit of groundwork here.  When someone becomes demented there seems to be a release, in some ways, that puzzles us because I have seen Alzheimer's patients who had very poor scores on their tests but who had great ability to maintain a sense of humor.  Depressed people are generally not laughing an awful lot, if at all.  I can only suppose that the lack of ability to function in certain areas of the brain which control our actions and judgment, may be at the root of this mirth.  No, I am not a neurobiologist and this is just an idea that came to me.  I stand corrected if I am totally wrong on this one or anything else.

If I were looking at some of this interesting question, I might wonder if a lack of depression meant there was a sufficient quantity of specific brain chemicals (a.k.a. neurotransmitters) that fought off the formation of the deadly plaques and tangles that form in the brain of Alzheimer's patients, in particular.  Could laughter and a positive outlook really be a "medication" that we should be dosing ourselves with on a daily basis?  Researchers constantly look for the reasons people are depressed, specifically those that are involved in our biology, but perhaps we need to turn the equation around. We need to look at happiness, not just in terms of brain hormones or blood substances, but as something currently beyond our understanding as a "treatment" for dementia. Who knows, it may, once again, boil down to goosing the immune system that protects us.

One of the things that I also vividly remember about the Alzheimer's patients that I saw in various parts of the country was that some of them had an extraordinary ability to make all of us laugh and to enjoy laughing.  True, there were some people who expressed their dementia as anger, but many of them were able to turn something mundane into something mirthful.  I'm thinking right now of several women who did just that.  For them, it wasn't just a means to laugh a bit, but actually a way of getting out of their testing that day.  The examiner would ask a question and they would receive an amusing question back and this would go on for maybe half an hour.  I understood then, as I do now, that the laughter helped with the pain. Who wants to be an accomplished architect who can't rememer where she lives?

Has the question of which came first, depression or dementia, been answered by this longitudinal study with its large sample?  No, it hasn't but it's another effort to solve yet another question in medicine.  And let's not forget that this particular area of research will have an increasingly important effect on all of us as our nation ages rapidly.  We need tests, we need treatments, and we need medications as well as lifestyle changes to help all of us maintain a happy, healthy and long life.

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