Sex differences in verbal memory in schizophrenia patients treated with “typical” neuroleptics

Abstract 

The relationship between sex and verbal learning and memory was investigated in 70 males and 36 females with a diagnosis of schizophrenia. Ninety-seven percent of the sample was receiving typical neuroleptic medication as treatment and had never received atypical medications. Selected scores from the California Verbal Learning Test (CVLT) [Delis, D.C., Kramer, J.H., Kaplin, E., Ober, B., 1987. The California Verbal Learning Test—Research Edition. Psychological Corporation, New York] were dependent variables in a series of hierarchical multiple regression analyses. Predictors comprised demographic, clinical and general cognitive measures. Sex was the most powerful predictor of both cumulative learning (Trial A5 recall) and the absolute number of words recalled after 20 min (Long-Delay Free Recall), accounting for 14% and 16% of score variance, respectively. Chlorpromazine-equivalent dose was negatively related to learning and recall. However, recall savings (Percent Retention) was unrelated to any predictor. This pattern of results parallels sex differences observed in the general population, albeit at a lower overall level of performance and with the suggestion of greater relative deficit in males. Schizophrenia does not eliminate and may even increase the advantage women demonstrate over men in some aspects of verbal memory.

Keywords:  Sex differences, Verbal memory, Antipsychotic medication