Premorbid IQ subgroups in first episode non affective psychosis patients: Long-term sex differences in function and neurocognition

Rosa Ayesa-Arriola*, Esther Setién-Suero, Karl David Neergaard, Àuria Albacete Belzunces, Fernando Contreras, Neeltje E.M. van Haren, Benedicto Crespo-Facorro

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

27 Citations (Scopus)


Background: Low IQ has been associated with schizophrenia, even to the point of being posited as a possible causal factor for psychosis. However, individuals with normal and high IQ also develop psychotic illnesses. The aim of this study was to characterize premorbid IQ subgroups at first episode of psychosis (FEP). Methods: The study sample comes from a large epidemiological, 3-year longitudinal, intervention program on psychosis containing individuals living in a catchment area in Spain. Estimated premorbid IQ (epIQ) scores were used to build low (< 90), normal (90–110) and high (> 110) epIQ subgroups in samples of FEP patients (N = 292) and healthy controls (N = 199). The epIQ subgroups were compared in sociodemographic, neuropsychological, clinical and premorbid characteristics. Long-term functional and cognitive outcome, with a focus on sex differences, were also explored. Results: Low-epIQ was more frequently found in FEP patients (28.8%) than in healthy controls (14.6%). Low-epIQ patients were more likely to have worse premorbid adjustment, belong to low socioeconomic status families, have less years of education, and to be single, unemployed, and younger. They presented more severe impairments in processing speed, executive and global cognitive function. Female patients with low-epIQ showed better baseline function and more stable outcome than males. Conclusions: Our results indicate that low premorbid IQ is a morbid manifestation, easily detected in a subgroup of FEP patients that predicts poorer outcome particularly in males. This perspective provides important information for the tailoring of subgroup-specific early intervention programs for psychosis.

Original languageEnglish
Pages (from-to)370-377
Number of pages8
JournalSchizophrenia Research
Publication statusPublished - Jul 2018
Externally publishedYes

Bibliographical note

Funding Information:
This work was supported by the Instituto de Salud Carlos III ( PI14/00639 and PI14/00918 ), Fundación Instituto de Investigación Marqués de Valdecilla ( NCT0235832 and NCT02534363 ) and Spanish Ministry of Education, Culture and Sport ( CAS15/00351 ). No pharmaceutical industry has participated in the study.

Publisher Copyright:
© 2017 Elsevier B.V.


Dive into the research topics of 'Premorbid IQ subgroups in first episode non affective psychosis patients: Long-term sex differences in function and neurocognition'. Together they form a unique fingerprint.

Cite this