1728 – Association between duration of untreated psychosis and progression of brain volume change in schizophrenia - the Northern Finland 1966 Birth Cohort

Abstract

Introduction Long duration of untreated psychosis (DUP) has been associated to brain morphological changes in schizophrenia in cross sectional analyses. It is unclear DUP relates to brain volume change over time. Aims Our aim was to analyze the association between length of DUP and total brain volume change in schizophrenia in a general population based sample. Methods All members of the Northern Finland 1966 Birth Cohort (NFBC1966) known to have had psychotic illness were invited for a field study at the age 34-years (in average 10 year after onset of psychosis) and follow up nine years later at the age 43-years. DUP was assessed from medical records. The total brain volume scan interval change and the DUP information were available for 32 subjects with DSM III R schizophrenia. We analysed the correlation between length of DUP and the mean annual whole brain reduction, adjusted for age of illness onset and sex. Results The mean annual whole brain volume reduction was 0.66%. The reduction was 0.76% among those with shortest DUP, 0.58% among those with median DUP, and 0.63% among those with longest DUP. There was no statistically significant correlation between DUP and annual brain volume change when adjusted for onset age and/or sex. Conclusions We did not find an association between long DUP and brain volume decrease in schizophrenia in 9 years follow up. Although long DUP has been associated with differences in brain volume in cross sectional analyses, the significance of DUP on brain morphology in long term is unclear.