Neurocognitive impairment in deficit and non-deficit schizophrenia: a meta-analysis


BORA İ. E., Akdede B. B., ALPTEKİN K.

PSYCHOLOGICAL MEDICINE, no.14, pp.2401-2413, 2017 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Review
  • Publication Date: 2017
  • Doi Number: 10.1017/s0033291717000952
  • Journal Name: PSYCHOLOGICAL MEDICINE
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Social Sciences Citation Index (SSCI), Scopus
  • Page Numbers: pp.2401-2413
  • Keywords: Cognition, deficit syndrome, schizophrenia, COGNITIVE IMPAIRMENT, NEGATIVE SYMPTOMS, NONDEFICIT FORMS, NEUROPSYCHOLOGICAL IMPAIRMENTS, NEUROIMAGING EVIDENCE, PSYCHOTIC DISORDERS, BIPOLAR DISORDER, SUBTYPE, IDENTIFICATION, MIND
  • Dokuz Eylül University Affiliated: Yes

Abstract

Background. Most studies suggested that patients with deficit schizophrenia have more severe impairment compared with patients with non-deficit schizophrenia. However, it is not clear whether deficit and non-deficit schizophrenia are associated with differential neurocognitive profiles. Methods. The aim of this meta-analytic review was to compare cognitive performances of deficit and non-deficit patients with each other and with healthy controls. In the current meta-analysis, differences in cognitive abilities between 897 deficit and 1636 non-deficit patients with schizophrenia were examined. Cognitive performances of 899 healthy controls were also compared with 350 patients with deficit and 592 non-deficit schizophrenia. Results. Both deficit (d = 1.04-1.53) and non-deficit (d = 0.68-1.19) schizophrenia were associated with significant deficits in all cognitive domains. Deficit patients underperformed non-deficit patients in all cognitive domains (d = 0.24-0.84) and individual tasks (d = 0.39-0.93). The relationship between deficit syndrome and impairment in olfaction, social cognition, verbal fluency, and speed-based cognitive tasks were relatively stronger. Conclusions. Our findings suggest that there is consistent evidence for a significant relationship between deficit syndrome and more severe cognitive impairment in schizophrenia.