The following is a summary of “Sex difference in association between tardive dyskinesia and cognitive deficits in patients with chronic schizophrenia,” published in the March 2023 issue of Schizophrenia Research by Zhang et al. 

Tardive Dyskinesia (TD) is a side effect due to long-term usage of antipsychotic medicines associated with cognitive impairment. Many studies also found sex differences in cognitive impairment in patients with schizophrenia. In contrast, there’s been no report of sex differences in cognitive performance in schizophrenia patients with TD.

For this study, 496 inpatients with schizophrenia and 362 individuals without the disorder were included. The assessment of the patients’ psychopathological symptoms was done through the Positive and Negative Syndrome Scale (PANSS), while the severity of TD was evaluated using the Abnormal Involuntary Movement Scale (AIMS). In addition, cognitive function was measured in 313 of the inpatients and 310 of the healthy controls using the Repeatable Battery for Assessment of Neuropsychological Status (RBANS).

The cognitive performance of patients with schizophrenia was inferior to that of healthy controls in all domains (p < 0.001 for all). Patients with TD had higher scores in PANSS total, PANSS negative symptom subscale, and AIMS scores compared to patients without TD (all p < 0.001), while their scores in RBANS total, visuospatial/constructional, and attention subscales were significantly lower (all p < 0.05). The study also found that male patients with TD had lower visuospatial/constructional and attention indices compared to those without TD (both p < 0.05), but this effect was not observed in female patients. Furthermore, only male patients showed a negative correlation between their visuospatial/constructional and attention indices and total AIMS scores (p < 0.05).

The findings of our study indicate that there could be variations in cognitive decline between males and females with schizophrenia and co-occurring TD, implying that being female might offer some defense against TD-induced cognitive impairment in schizophrenia patients.