Sex differences in cognition among persons with schizophrenia and healthy first-degree relatives.
Previous research suggests differences between women and men in the clinical features of schizophrenia, but studies examining sex differences in neuropsychological functioning have reached inconsistent results. In the present study, sex differences in cognition and clinical features were investigated in population-based samples of participants with schizophrenia (n=218), their healthy first-degree relatives (n=438) and controls (n=123). Sex differences in illness features were small; nevertheless, women with schizophrenia had less negative symptoms and lived independently more often than men. The schizophrenia group had impairments in all studied neuropsychological domains, and the relatives were impaired in processing speed and set-shifting. In all groups, women performed better than men in processing speed, set-shifting and verbal episodic memory, whereas men outperformed women in visual working memory. The group-by-sex interaction was significant in two variables: women outperformed men in the relatives group in immediate verbal reproduction and in the use of semantic clustering as a learning strategy, while there was no sex difference in the schizophrenia group. In conclusion, sex differences in cognition are mostly similar in schizophrenia to those among controls, despite sex differences in illness features. The preservation of sex differences also in first-degree relatives supports the conclusion.
Department of Mental Health and Substance Abuse Services, National Institute for Health and Welfare, Mannerheimintie 166, 00271 Helsinki, Finland. minna.torniainen@thl.fi
Minna
M
Torniainen
Jaana
J
Suvisaari
Timo
T
Partonen
Anu E
AE
Castaneda
Annamaria
A
Kuha
Jonna
J
Perälä
Samuli
S
Saarni
Jouko
J
Lönnqvist
Annamari
A
Tuulio-Henriksson
D000328:Adult; D000368:Aged; D001288:Attention / Q000502:physiology; D016009:Chi-Square Distribution; D003072:Cognition Disorders / Q000209:etiology* / Q000235:genetics; D005190:Family / Q000523:psychology; D005192:Family Health; D005260:Female; D006801:Humans; D008297:Male; D008568:Memory / Q000502:physiology; D008875:Middle Aged; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D012559:Schizophrenia / Q000150:complications* / Q000235:genetics*; D012727:Sex Characteristics; D014706:Verbal Learning / Q000502:physiology