Comparison of basic neurocognitive violations in patients with residual schizophrenia with and without history of ischemic stroke
Authors: Darii V. , Safonov D. 
Published: September 2023

Relevance. The cognitive symptoms associated with schizophrenia have been a subject of controversy and are often viewed through a dualistic lens. According to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), these cognitive symptoms can be further elucidated within specific neurocognitive domains.

Many of the symptoms of schizophrenia manifest behaviorally and can be challenging to differentiate from the consequences of organic brain impairment, especially when these symptoms involve the frontal and temporal cortex or have a diffuse presentation.

Aim – to evaluate neurocognitive deficit in patients with residual schizophrenia with history of ischemic stroke.

Materials and methods. A comprehensive study was conducted involving 100 patients diagnosed with recurrent schizophrenia (ICD-10: F20.5) at the Communal Non-Profit Enterprise "Regional Clinical Institution for the Provision of Psychiatric Care". We selected 59 patients: 32 patients with residual schizophrenia without history of stroke (Group 1, G1) and 27 patients with residual schizophrenia with history of stroke (Group 2, G2). Neuropsychological testing was used to evaluate neurocognitive violations. Due to massive distortions that brought to testing results by schizophrenia negative symptoms, only general evaluation was made to reflect critical or non-critical to no violations in separate functions. Statistical method of chi-square test was used to compare results in groups. 

Study results. To compare neurocognitive violations in G1 and G2 we performed neuropsychological testing in basic neurocognitive domains. G2 patients, diagnosed with both schizophrenia and a stroke, generally exhibit heightened cognitive impairments compared to G1 patients with only schizophrenia. Notably, deficits in Sustained Attention, Divided Attention, Processing Speed, Working Memory, Mental Flexibility, immediate memory, implicit learning, and both expressive and receptive language are more pronounced in G2 patients. However, for functions like Selective Attention, Planning, Decision-Making, recent and very-long-term memory, and interpersonal understanding, the added influence of a stroke in G2 doesn't drastically differentiate them from G1. In essence, while schizophrenia inherently poses cognitive challenges, the co-occurrence of a stroke amplifies certain deficits but not others. This data suggests a complex interplay between schizophrenia and stroke in influencing cognitive function.

Conclusions. The coexistence of schizophrenia and a history of stroke in G2 patients frequently exacerbates certain cognitive impairments when compared to those diagnosed solely with schizophrenia. This underlines the compounded cognitive challenges faced by patients with comorbid conditions. However, for some cognitive domains, the severity of impairments is primarily governed by schizophrenia, irrespective of the presence of an additional stroke history. This comprehensive analysis underscores the complex interplay of multiple conditions on cognitive function and emphasizes the importance of individualized care and intervention strategies tailored to the specific cognitive challenges faced by each patient group.