Schizoaffective disorder is a less well-known diagnosis than schizophrenia, depression, or bipolar disorder, and it tends to confuse people. It was categorized under schizophrenia in earlier versions of the DSM, but in the current version you have to have a mood episode for a “substantial portion” of the time, as well as having psychotic symptoms outside of a mood episode.
That last bit is important because some people with bipolar disorder have psychotic symptoms during manic periods, and some people with bipolar disorder and some people with major depressive disorder have psychotic symptoms during depression. But (according to the DSM-IV) they don’t have psychotic symptoms outside of mood episodes.
But we don’t know from this what schizoaffective disorder actually is. Is it having both a mood disorder and schizophrenia at the same time? Is it a separate disorder from either? (And what about if your depression isn’t long enough or severe enough to be schizoaffective disorder and you get diagnosed with schizophrenia with comorbid depression? Is that a totally different thing?)
Goodwin and Jamison do a quick review, which I will summarize:
The five major schools of thought are:
- a separate disorder (but it doesn’t run in families, so this seems less likely)
- “an intermediate form on the continuum of psychosis” (I think this means that if you think of disorders as lying along a continuum of psychosis, like you could think of bipolar symptoms as lying along a continuum of severity, schizoaffective is inbetween schizophrenia and bipolar with psychotic symptoms)
- comorbid schizophrenia and depression/bipolar
- more severe bipolar
- less severe variant of schizophrenia
Another school of thought might be that schizoaffective disorder is actually several different things, which is what they tentatively suggest (we’re a little short on actual research to draw strong conclusions):
- People who are primarily manic and less pronouncedly psychotic may have an especially severe form of bipolar disorder (suggested by studies showing that it is more associated with bipolar disorder and has a worse course: Gershon et al, 1982; Coryell et al., 1990).
- People who are predominantly psychotic and have less prominent, exclusively depressive symptoms may have a less severe variant of schizophrenia (suggested by studies showing outcomes or neuropsych profiles similar to schizophrenics: Brockington et al, 1980; Tsuang and Coryell, 1993; Evans et al, 1999).
- People who have about an equal mix are the unlucky bastards who just happened to get both a mood disorder and schizophrenia. (suggested by the epidemiological prevalence of the disorder being a fraction of a percent, about what you’d expect for those two just happening to co-occur: Kendler et al, 1993, 1996).
Again, this is still speculative and we don’t have enough research to confirm (or deny) it. But it’s pretty interesting, no? Maybe we’ll get a bipolar 0.5 to complement I and II? Since all the love’s been going in the other direction, maybe it’s time the crazier among us got a little more attention. And what kind of “less severe” schizophrenia manages to hit you with something akin to major depressive disorder, yet still be less disabling than regular schizophrenia?