Lack of Association Between Duration of Untreated Illness and Severity of Cognitive and Structural Brain Deficits at the First Episode of Schizophrenia

Untreated Initial Psychosis: Relation to Cognitive Deficits and Brain Morphology in First-Episode Schizophrenia

“…If such pathogenic processes are also present around the onset of clinical symptoms, it appears that untreated psychosis is not a contributing factor. On the basis of our findings as well as those of other investigators (19,20,22,36), the pattern of mostly small correlation coefficients and the paucity of significant differences between patients with long and short duration of untreated initial psychosis do not support the frequently expressed belief that long periods of untreated psychosis have a pronounced impact on neurocognitive functioning or on brain morphology in schizophrenia.…”

“…However, studies that have specifically examined the relationship between duration of untreated initial psychosis and outcome have had more mixed findings (4) and call into question the plausibility of toxicity from untreated psychosis. Although there are presently still more publications in the literature reporting on the association between long duration of untreated initial psychosis and poor outcome (7)(8)(9)(10)(11)(12)(13)(14)(15)(16), an increasing number of studies published during the past 3 years have failed to find this association (17)(18)(19)(20)(21)(22).…”

“…Hoff et al (19) reported that Spearman's rank order correlations between duration of untreated initial psychosis and measures of the lateral ventricles, cerebral hemisphere, and temporal lobe ranged from 0.03 to 0.15. None of these correlations was statistically significant in their sample of 50 first-episode schizophrenia patients.…”

“…Some studies have found long duration of untreated initial psychosis to be associated with poorer outcome (7-16), while others have not (17)(18)(19)(20)(21)(22). The reasons for these conflicting findings may be related to differences in sampling, power, and statistical methods (4,45) as well as in the reliability and validity of measuring the duration of untreated initial psychosis (46).…”

First-episode schizophrenia: review of cognitive deficits and cognitive remediation

“…But Norman et al (2001) and Hoff et al (2000) found no relationship between duration of untreated psychosis and performance on any component of neuropsychological functioning, suggesting that there is no support for the toxic effect of duration of psychosis on cognitive functioning. However, these findings cannot be generalised because they have not included results from long-term follow-up.…”