The results might ease fears about overtreating people who have warning signs of psychosis but not a full-blown disease, but the study findings were not conclusive because the number of participants was too small.
"This shows it's quite safe and reasonably effective to offer supportive psychosocial care to these patients," Dr. Patrick McGorry, an author of the study, told Reuters Health. There is "no evidence to suggest that antipsychotic medications are needed in first-line" treatment, he said.
The clinical trial included 115 clients of a Melbourne, Australia, clinic for young people deemed to be at "ultra-high risk" for a psychotic disorder such as schizophrenia.
The study was open to individuals between the ages of 14 and 30 who met at least one of three criteria: having low-level psychotic symptoms, having had previous brief episodes of psychotic symptoms that went away on their own or having a close relative with a psychotic disorder along with low mental functioning during the past year.
The study compared three regimens: talk therapy focused on reducing depression symptoms and stress while building coping skills plus a low dose of the antipsychotic risperidone, or talk therapy plus a placebo pill or therapy emphasizing social and emotional support plus a placebo.
The goal was to see how many participants in each group progressed to full-blown psychosis.
After a year, there was no notable difference between the groups, however about 37 percent of the participants dropped out during the study. McGorry said if the trial had included more people, significant differences between the groups might have emerged.
The study appears online in the Journal of Clinical Psychiatry.
Researchers have been working to identify people at risk of developing psychotic disorders. "The importance of detecting early signs and symptoms of a serious mental illness is not controversial," said Dr. Matcheri Keshavan, a professor of psychiatry at Harvard Medical School. "But the best way of treating or preventing it remains controversial."
McGorry, a professor at the Centre for Youth Mental Health at The University of Melbourne, said that only about 36 percent of high-risk individuals will likely progress to psychosis within three years. So many health professionals worry about the prospect of treating everyone at risk with drugs, which come with side effects.
Another concern is that individuals will carry the label of mental illness unnecessarily.
McGorry said that the "vast majority" of the at-risk young adults in the study, most of them university-age, met the requirement for some kind of mental illness. That's why all the participants received some level of care, even if it was just basic emotional and social support and coping skills.
The rates of progression to full-blown psychosis - which ranged from about 10 percent to about 22 percent - were lower in all three groups than in previous studies.
It's not clear why, but McGorry said it's possible that more participants will develop psychosis after the end of the 12-month study period. Many of the study participants were also taking antidepressants, which may have eased psychotic symptoms.
As with many trials, most participants showed poor adherence to the medications used, which may have influenced the results, the authors note.
McGorry was also an author of a 2010 study that found fish oil supplements might prevent psychosis in the same type of at-risk individuals. That research continues, he said.
Going forward, "what is needed is some way of finding predictive biomarkers that can tell who might be at the highest risk," said Keshavan. "We need to understand their brains."
McGorry and some of his co-authors have served as consultants or received research funding from pharmaceutical companies. One of them, Janssen-Cilag, which developed risperidone, partially funded the study.
SOURCE: http://bit.ly/XdZLx2 Journal of Clinical Psychiatry, online November 27, 2012.