Course of intelligence deficits in early onset, first episode schizophrenia: a controlled, 5-year longitudinal study

Jens Richardt Moellegaard Jepsen, Birgitte Fagerlund, Anne Katrine Pagsberg, Anne Marie R. Christensen, Rikke W. Hilker, Merete Nordentoft, Erik L. Mortensen

Research output: Contribution to journalJournal articleResearchpeer-review

19 Citations (Scopus)

Abstract

Only few prospective longitudinal studies have assessed the course of intelligence deficits in early onset schizophrenia (EOS), and these have used different age appropriate versions of Wechsler Intelligence Scales and age appropriate norms. The post-psychotic development of intelligence in EOS has predominantly been characterized as relatively stable in these studies. However, comparisons of IQs from different test versions based on the different norms may not permit unequivocal interpretations. The objective of the current study was to compare the development of intelligence in EOS patients (N = 10) from their first psychotic episode to 5 years of post onset with that of healthy controls (N = 35) and patients who at baseline had been diagnosed with other non-affective psychoses (N = 8). The same version of a Wechsler Intelligence Scale was administered at both baseline and follow-up assessments, and the same norms were used to derive IQs at baseline and follow-up. Significantly smaller change in mean full scale intelligence quotient (FSIQ) was found in diagnostically stable EOS patients compared with healthy controls during the follow-up period. However, no statistically significant difference in mean FSIQ change was observed between patients with EOS and patients with other non-affective psychoses, although this result must be interpreted with caution due to the small sample sizes. The results suggest abnormally slow acquisition of new intellectual information and skills in EOS patients during the first 5 years after full clinical presentation.
Original languageEnglish
JournalEuropean Child & Adolescent Psychiatry
Volume19
Issue number4
Pages (from-to)341-351
Number of pages11
ISSN1018-8827
DOIs
Publication statusPublished - 1 Apr 2010

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