I can't remember when I first decided that the psychiatric classifications I'd learned in medical school had outlived their usefulness. It was probably a gradual process, but by 2005 I wrote to a colleague "DSM IV was great in its day, but new knowledge is breaking down the simplistic classifications of the 1960s and 1970s. Schizophrenia, autism, etc -- bah, humbug. Those labels are better than nothing, but humans tend to confuse labels with reality …".
After a bit of a hiatus the end came quickly, first with a frontal attack by the director of the National Institutes of Mental Health, then, amazingly, a NYT editorial. I mean, really, an editorial?
It's been one heck of a ride over the past 8 years. This rebellion must have been brewing for much longer in the research community, but I've been following this area pretty closely and it was cool to see it grow from nowhere to become a consensus. (I may be a crank, but I'm not crazy. I know my posts had no effect on this transformation.)
Okay, science has won. So now what ….
Well, for now, we keep on using our legacy classifications -- either DSM IV or V, they're equally valid and equally invalid. Terms like "autism" , "schizophrenia", "depression", OCD, ADHD, and "bipolar disorder" will remain guides to initial pharmaceutical therapy. Even more importantly, they will be the basis of reimbursement, regulation, disability support, and legal process for years (decades?) to come.
At the same time researchers will be using new terms to group people who seem to share common biology, including genetic programs and common protein expression. Those groups will cross traditional boundaries like childhood schizophrenia and autism; they will include some atypical minds that may be highly functional or advantageous in certain environments -- but that share traits with persons who live with disability.
From new classifications will come better prognosis, better guides to treatment, and better outcomes. Our best guide to what lies ahead is to look back to the early 20th century, when people like William Osler and his colleagues rewrote the medical textbooks. In those days terms like "dropsy" were used to describe patients with heart failure, renal failure, lymphatic obstruction and venous valve failure. Four very different biological processes were assigned the same label and similar treatments. Reclassifying those patients was a first step towards scientific medicine.
Psychiatry, powered by the neuroscience renaissance of the past thirty years, is now taking the same journey.
 Aspergers', traditionally considered an autism variant, was dropped in the revised classification of disorders called DSM V. I understand the logic, but I actually think Aspergers was a relatively useful label. Ironic that we lost that one first.
Update 5/18/13 - my favorite psychiatrist blogger summed up our past and future worlds in two short posts: