Schizoaffective disorder: A challenging diagnosis

Clinical symptoms

The signs and symptoms of SAD include those typically seen in schizophrenia and the mood disorders. Thus, the patient may exhibit elated mood and/or grandiosity, or severe depression, combined with mood-incongruent psychotic features such as paranoid delusions. The symptoms may present together or in an alternating fashion, and psychotic symptoms may be mood-congruent or mood-incongruent. Mr. C’s case illustrates some of the symptoms of the disorder.

Brain imaging

Significant changes have been reported to occur in the brain structure and function in persons with SAD. Neuroimaging studies using voxel-based morphometry have shown significant reductions in gray matter volume in several areas of the brain, including the medial prefrontal cortex, insula, Rolandic operculum, parts of the temporal lobe, and the hippocampus.^32-35 Amann et al³² found that patients with SAD and schizophrenia had widespread and overlapping areas of significant volume reduction, but patients with bipolar disorder did not. These studies suggest that at least from a neuroimaging standpoint, SAD is more closely related to schizophrenia than bipolar disorder, and could represent a variant of schizophrenia.

Treatment of SAD

The pharmacotherapy of SAD is mostly empirical because of the lack of randomized controlled trials. Clinicians have traditionally prescribed an antipsychotic agent along with either a mood stabilizer (eg, lithium, valproate) or an antidepressant, depending on the patient’s SAD subtype. Jäger et al³⁶ reviewed 33 treatment studies published up to 2007 that employed widely accepted diagnostic criteria and reported results for SAD patients. They concluded that mood stabilizers and antipsychotics appeared to be effective, but that it was not possible to provide treatment guidelines.

Since that exhaustive review, aripiprazole was compared with placebo in 2 separate trials that include patients with schizophrenia and patients with SAD.³⁷ In a pooled sub-analysis of SAD, aripiprazole was found to be more effective on some but not all measures, suggesting efficacy. Based on 2 randomized controlled trials, the FDA approved the use of paliperidone, an SGA, as monotherapy in the acute treatment of SAD and in combination with mood stabilizers and/or antidepressants.^38,39 It is likely that other SGAs are also effective.

Patients with SAD will require maintenance treatment for ongoing symptom control. Medication that is effective for treatment of an acute episode should be considered for maintenance treatment. Both the extended-release and long-acting injectable (LAI) formulations of paliperidone have been shown to be efficacious in the maintenance treatment of patients with SAD.⁴⁰ The LAI form of paliperidone significantly delayed psychotic, depressive, and manic relapses, improved clinical rating scale scores, and increased medication adherence.^41,42 In an open-label study, olanzapine LAI was effective in long-term maintenance treatment, although approximately 40% of patients experienced significant weight gain.⁴³ One concern with olanzapine is the possible occurrence of a post-injection delirium/sedation syndrome. For that reason, patients receiving olanzapine must be monitored for at least 3 hours post-injection. The paliperidone LAI does not require monitoring after injection.

Continue to: There is a single clinical trial...