Objective: The aim of the present study was to identify the relationship between duration of untreated psychosis (DUP), premorbid functioning, and cognitive dysfunction and the outcome of first-episode schizophrenia.
Method: Thirty-four neuroleptic-naïve patients who consulted hospitals in Tokyo and who were treated by psychiatrists for the first time were evaluated with regard to DUP, premorbid functioning, psychiatric symptoms, and global functioning. The neuropsychological test battery consisted of the Letter Cancellation Test, Trail-Making Test, Digit Span and Verbal Fluency Test. One year later, 24 of the subjects were reassessed for psychiatric symptoms, global functioning, and social functioning, and the relationships between DUP, premorbid functioning, and cognitive performance and the outcome was investigated.
Results: Short DUP, good premorbid functioning, and good Letter Cancellation Test, Digit Span and Verbal Fluency Test scores were significantly associated with good outcome.
Conclusions: The present results in a Japanese sample are consistent with previous international evidence that delay of initial treatment, premorbid functioning, and cognitive deficits are associated with outcome. A major limitation of the present study was the small size of the subject group. But because the subjects were relatively homogeneous and not influenced by psychoactive substances, the results reflect the essence of the disorder.