BERLIN – The redefinition of schizoaffective disorder unveiled in the DSM-5 leaves much to be desired, experts opined at the annual congress of the European College of Neuropsychopharmacology

“We all thought we had the solution for making new criteria for schizoaffective disorder,” recalled Dr. Jim van Os, who served on the DSM-5 committee charged with reexamining the disorder. “But in the end, nothing much changed.”

Indeed, despite the lofty ambitions he and many of his fellow DSM-5 committee members held for thoroughly overhauling the criteria for what he called “this enigmatic combination of affective and psychotic dysregulation,” the difference between the DSM-IV and DSM-5 boiled down to small potatoes: Whereas the DSM-IV stated that the diagnosis of schizoaffective disorder required that the mood episode must be present for “a substantial duration of the illness,” the DSM-5 requires that the mood episode be present for “the majority” of the illness.

“The change was made to improve the reliability and stability of the diagnosis,” explained Dr. van Os, professor of psychiatric epidemiology at Maastricht (the Netherlands) University.

He was an advocate on the committee for introducing a dimensional approach to the diagnosis of schizoaffective disorder, one that would incorporate consideration of clustering of symptoms across a continuum.

“This would have been the best solution to the conundrum of the ‘fuzzy set’ problem of mental disorders. It would have been a great way of recognizing the continuity of all mental phenomena seen in mental disorders. However, it did not happen, unfortunately.”

The psychiatrist noted that committee members debated “for many hours” how best to overhaul the criteria for schizoaffective disorder in the DSM-5 before deciding to scale back their scope.

“We realized that any measure of precision in the criteria we tried to introduce for the admixture of affective dysregulation and psychosis is spurious. We really haven’t got the tools yet to make valid distinctions. That’s why we said in DSM-5 that the clinician can make the diagnosis using clinical intuition that the majority of time in the illness there is affective dysregulation. So, not spurious precision, but clinical intuition. I don’t know if that’s a good decision, but that’s what we did,” Dr. van Os said.

At the same symposium on schizoaffective disorder held during the ECNP congress, Dr. Heinz Grunze declared: “I would have welcomed as a development in DSM-5, as we’ve seen with some other disorders, basically abolishing schizoaffective disorder on its own and assigning it either to bipolar disorder with psychotic features specified or to schizophrenia with a strong affective specifier. I think that would be better suited to characterizing these patients.”

“Clearly, schizoaffective disorder has quite a polymorphic course. It’s definitely not one illness; it’s several illnesses which we put together in this random category,” added Dr. Grunze, professor of clinical psychiatry at University of Newcastle (England).

His own view is that the disorder belongs under the umbrella of bipolar disorder. A recent Spanish functional magnetic resonance brain imaging study demonstrated that schizoaffective disorder exhibits features that more closely resemble those of bipolar disorder than schizophrenia, including the finding that patients in clinical remission show failure of deactivation in the medial frontal gyrus, compared with healthy controls, Dr. Grunze noted.

“I personally can’t see a difference between a schizoaffective acute episode, manic type, and a psychotic manic episode. So my personal opinion is that schizoaffective disorder belongs under the heading of bipolar disorder. That’s obviously different from the opinion of those conducting treatment trials and the pharmaceutical industry, where schizoaffective disorder is never a subgroup in bipolar disorder trials, but a subgroup in schizophrenia trials,” Dr. Grunze said.

One audience member rose to state that while all this wrangling over how best to subclassify these patients is interesting, why not take a pragmatic approach and simply treat them symptomatically?

“Well, I think that’s what everyone in this room who’s a clinician is doing,” Dr. Grunze replied. “Because even if we assume that the diagnosis itself might be unstable, I think the greatest variance in patients switching around between bipolar, schizophrenia, and schizoaffective comes from the different doctors seeing them, each having a different understanding of schizoaffective disorder. I see a lot of patients who are classified as schizoaffective disorder because they have what I would have considered just as mood-congruent psychotic symptoms while manic. So I absolutely agree with you that this is more of an academic discussion, really, because at the moment we don’t have any consequences for treatment. We don’t have good evidence about how to treat these patients; we just extrapolate from whatever we think their symptoms come closest to.”

He reported receiving research grants from the National Institute for Health Research and the U.K. Medical Research Council, as well as more than a half-dozen pharmaceutical companies.

Dr. van Os reported having no financial conflicts.

bjancin@frontlinemedcom.com

Redefined schizoaffective disorder in DSM-5 seen as problematic