The Separation of Depression and Bipolar in the New DSM-5
The Diagnostic and Statistical Manual of Mental Disorders (the DSM) is frequently called psychiatry’s “bible.” I, however, would not pen it that way. I would suggest that the DSM is simply a guideline for the diagnosis of mental illness. It lists the criteria one has to have in order to be diagnosed with a mental illness.
And, as the name of this post suggests, the DSM is releasing its fifth major version – the DSM-5 – in just a couple of weeks.
Now, the DSM-5 has been controversial from the get-go and I have said that much of this controversy is overstated, but some of the changes do have fundamental nosological implications. In other words, some of the changes in the DSM-5 can change how people fundamentally think of certain mental illnesses.
The DSM-5 Cuts the Chord between Depression and Bipolar
And one of the changes in the DSM-5 is the separation of major depression and bipolar disorder into their own chapters. No longer is there a chapter called “Mood Disorders” with both disorder types listed (Can we still call them mood disorders?). Now they each represent a separate category.
This may seem like a small change, and I’m not going to have a fit over it, but I will say that I think it was the wrong move.
Depression and Bipolar Disorder – Separate but Equal
You see, it is my belief that bipolar disorder is not so much separate from major depression as much as the two are at either ends of a spectrum, like so:
Because it’s clear to me that bipolar disorder doesn’t just come in three flavours: bipolar I, bipolar II and cyclothymia, it also comes in a myriad of textures in between. I think it’s entirely possible to be diagnosed with depression with just a soupçon of bipolar disorder thrown in there for colour.
Indeed, the fact that we have multiple versions of bipolar disorder, each “less manic” than the next, suggests that depression is the outstanding feature of all and the mania is the variable. So we all have depression but some of us have these other odd moods too – to varying degrees.
So it makes all the sense in the world to group these disorders together. But, as I said, they are no longer grouped.
The Problem with a Depression / Bipolar Dichotomy
What I’m saying is that the idea of a depression / bipolar dichotomy is false and this matters because of the implications to treatment. If depression really were completely separate from bipolar disorder then why would anyone with depression have a beneficial reaction to anything other than antidepressant medication? (And this is often the case. Many people with depression are on effective medications other than antidepressants.) And should anything but antidepressants be tried on just a straight major depressive population?
Now, I suppose when it comes down to it, it’s a philosophical difference because I highly doubt it will change prescribing practices one bit. Nevertheless, I think forgetting that bipolar and depression are on ends of a spectrum does a disservice to patients and to research where this concept could be critical to our understanding of affective disorders in general.
And moreover, it has never been made clear to me what the advantage of the separation is. If we admit that patients do not fit nicely into boxes (and we do admit that, that is why there is a diagnosis of “not otherwise specified”) then why are we just creating higher walls on said boxes? It’s silly. I don’t get it. And I don’t think it reflect the reality of patients, doctors or treatments at all.