In three pieces this week on my blog Knowledge is Necessity, I happened to use a clinical trial of Invega on patients with schizoaffective disorder as a case study in how randomized, double-blind, placebo controlled studies - the gold-standard in treatment research - all too often tell us nothing.

The exercise got me thinking about schizoaffective, and when I noticed that Marcia Purse had just posted something on the topic here at BipolarConnect, I thought now would be a good time to jump in.

Back in the early twentieth century, the pioneering diagnostician Emil Kraepelin separated out “manic-depression” (bipolar and recurrent depression) from “dementia praecox” (which his followers changed to schizophrenia). In effect, this gave psychiatry its basic navigating system which we still use today. But even back then Kraepelin had second thoughts about making such a decisive distinction.

In 1933, American psychiatrist Jacob Kasanind proposed “schizoaffective psychosis” in the Freudian context as a type of a good prognosis schizophrenia. In 1959, German psychiatrist Kurt Shneider employed the term schizoaffective to fill in the middle ground between Kraepelin’s manic-depression and schizophrenia.

Schizoaffective is probably the most confusing of all the 297 psychiatric disorders listed in the DSM-IV. The DSM-5 work group responsible for coming up with something better actually acknowledged that “the current DSM-IV-TR diagnosis schizoaffective disorder is unreliable,” but failed to do anything to remedy the situation. Is schizoaffective a type of “schizophrenia lite” or “heavy-duty bipolar?” Or do we have both bipolar and schizophrenia co-occurring together?

Or is it some of one and some of the other? Or is it a separate illness in its own right? Perhaps none of the above?

The DSM appears to lean on the side of “schizophrenia lite” combined with a mood disorder. The illness is classified under “Schizophrenia and Other Psychotic Disorders.” Thus, a patient must present with schizophrenia symptoms (such as delusions and disorganized speech) but without six months of continuous disturbance (involving at least one month of being fully symptomatic). But at the same time, the patient is experiencing a full-blown depressive, manic, or mixed episode.

Clear as day, right?

So, what if you experience psychosis (such as delusions) when you are manic or depressed? Schizoaffective, right? Not necessarily. Psychosis occurs across a number of disorders. Thus we have DSM bipolar “with psychotic features” and DSM depression “with psychotic features.”

Meanwhile, we know that a lot of individuals with schizophrenia also experience depression.

Confused? So is your psychiatrist. I can almost guarantee that if you are currently diagnosed with schizoaffective you were first diagnosed with something else. Likewise, a good many of you with a current bipolar diagnosis may have received a schizoaffective diagnosis in your past.