Speaking at the American Psychiatric Association meeting in Hawaii, Ehret said she and others conducted a retrospective study in which they examined a large sample of hospitalized patients at Hartford Hospital’s Institute of Living who were diagnosed with schizophrenia (n=1519).
"We wanted to determine the proportion for whom antidepressants were prescribed and whether there were any demographic or clinical variables that distinguished these patients from others with schizophrenia," she explained.
The sample involved consecutive inpatient admissions for adults aged 18 to 64 who were discharged over a 9-year period (February of 2000 to June of 2009). Researchers recorded patient demographics, co-diagnoses and psychotropics prescribed.
Of the patients discharged with a schizophrenia diagnosis, 31% were receiving an antidepressant.
"But we eliminated trazodone and the tricyclics, because preliminary analyses showed they were prescribed as sedatives at dosages subtherapeutic for depression," she noted.
After eliminating those antidepressant categories, 28% of the patients were receiving antidepressants— primarily selective serotonin reuptake inhibitors, she said.
Of the patients with schizophrenia who also received antidepressants, 6.8% had a co-diagnosis of depression. An additional 4.9% had a co-diagnosis of anxiety disorder, and another 8.5% had a co-diagnosis of personality disorder.
Regression analyses also revealed that patients receiving antidepressants were more likely to be Latino, less likely to be black, and more likely to be receiving atypical rather than typical antipsychotics.
There was no association with age, gender, hospital length of stay, or readmission within 1 year.
These findings, Ehret said, may be very relevant to recent reports about antidepressant add-on use for negative symptoms. She indicated that 3 meta-analyses have demonstrated that the combination of antipsychotics and antidepressants may be effective in treating negative symptoms of schizophrenia.
The study findings may also be helpful in determining DSM-5 distinctions between schizophrenia, schizoaffective disorder and psychotic mood disorders. In patients with schizoaffective disorder, she said, 49% were prescribed adjunctive antidepressants.
