طیف به هم ابتلایی وسیع با کارکرد اجرایی بهتر در یک نمونه بیماران بستری افراد مبتلا به اسکیزوفرنی در ارتباط است

Background Individuals with schizophrenia exhibit cognitive deficits but whether these deficits are exacerbated by broad spectrum psychiatric comorbidity (i.e., comorbidity that is inclusive of disorders from different diagnostic categories) is unclear. A broad spectrum approach to psychiatric comorbidity is an ecologically valid way to capture the diagnostic heterogeneity inherent in psychiatric presentations. Objective This study compared the attention, working memory, processing speed, and executive functioning of individuals with schizophrenia only relative to individuals with schizophrenia and broad spectrum psychiatric comorbidity. Method Archival patient neuropsychological test data was obtained for a sample of patients with schizophrenia only (n = 30) and a sample of patients with schizophrenia and psychiatric comorbidity (n = 33). Relevant tests were used to form composite indices for the cognitive domains of attention, working memory, speed of processing, and executive functioning. Results Unexpectedly, individuals with schizophrenia and psychiatric comorbidity had significantly better executive functioning than individuals with schizophrenia only. There were no other significant differences. Conclusions A broad spectrum approach to psychiatric comorbidity can help to account for differences in the executive functioning of individuals with schizophrenia. In clinical settings, individuals with schizophrenia and psychiatric comorbidity may benefit from intervention strategies that capitalise on their relatively higher executive functioning.

Cognitive deficits are an important part of the presentation of schizophrenia and have been shown across cognitive domains to be between 0.5 and 2 standard deviations below that of healthy individuals [1,2]. Schizophrenia also commonly occurs with other psychiatric disorders such as mood, anxiety, and substance-related disorders [3,4]. An important line of research has examined whether comorbid psychiatric disorders pose an additional cognitive burden on the cognitive functioning of individuals with schizophrenia. From a theoretical perspective, transdiagnostic models of psychopathology have highlighted common maladaptive cognitive processes across psychiatric disorders that interfere with normal cognitive functioning (e.g., attentional biases, automatic thoughts, ruminative thinking; [5]). Thus, these models suggest that the cognitive deficits of schizophrenia may be exacerbated by the presence of comorbid psychiatric disorders. (See Fig. 1.) (See Table 1 and Table 2.) Full-size image (93 K)