The findings of a study in the Journal of Psychiatric Research suggest a relationship between positive psychotic symptoms and depressive symptoms, as well as the existence of a treatment-resistant population with co-occurring psychosis and depression.
Second-generation antipsychotic medications are already used to help patients with treatment-resistant depression, but for those who have an additional psychotic disorder, the heterogeneity of symptoms makes evidence of their efficacy harder to ascertain.
The authors recruited 226 patients admitted to an acute psychiatric ward for psychosis. Patients had a mean age of 34.1 years; 44.2% had not taken an antipsychotic medication, and 54.9% had a diagnosis within schizophrenia spectrum disorders (ClinicalTrials.gov identifier: NCT00932529). Eligible participants were candidates for risperidone, olanzapine, quetiapine, or ziprasidone; clozapine candidates were excluded. Participants met International Statistical Classification criteria for a psychotic disorder and had a score of ≥4 on a relevant Positive and Negative Syndrome Scale item, such as delusions or hallucinations.
To examine experiences with depression among patients with psychosis, the authors used the Calgary Depression Scale for Schizophrenia, a tool developed to distinguish negative subscale psychotic symptoms from depression alone. The most commonly represented psychotic disorders were schizophrenia and delusional disorders; schizophrenia was associated with lower depression scale scores.
The authors followed up at patient discharge (mean 4.1 weeks) or 6 weeks, 3 months, and 6 months, and identified 3 distinct trajectories in their analyses.
A first group of patients had low-level depressive symptoms. These patients tended to be more disorganized, less cooperative, and had a lower psychopathology score overall.
A second group appeared to be early responders — patients who began the trial with considerable depressive symptoms but who saw a steep decline in severity early on. The authors were unable to identify characteristic differences between the early responders and treatment-refractory individuals.
A third group had debilitating, high-level depressive symptoms that appeared treatment resistant; these patients remained severely depressed at 6 months. Most were also receiving antidepressant therapy.
Across all groups, those who saw a greater reduction in positive subscale symptoms saw a greater reduction in depressive symptoms, an association which aligns with the findings of previous research.
Although the study was strengthened by its relevant clinical setting and representative population, the authors noted that the attrition rate was high and pointed out that patients who drop out of studies tend to be more severely depressed. Further research is needed to identify options for this treatment-resistant population.
“The main message from the present paper is to carefully identify the psychotic patients that do not improve from their debilitating depressive symptoms during an acute phase of psychosis,” the researchers wrote. “These patients are candidates for an enhanced treatment plan, for which current evidence is limited.”
Kjelby E, Gjestad R, Sinkeviciute I, et al. Trajectories of depressive symptoms in the acute phase of psychosis: implications for treatment. J Psychiatr Res. 2018;103:219-228.