Purpose: Insomnia is a major public health concern that often occurs in patients with schizophrenia, complicating the treatment and prognosis of patients. This study aimed to investigate the prevalence of insomnia and its relationship with cognitive function in Chinese patients with chronic schizophrenia.
Methods: We recruited patients with schizophrenia and collected their clinical and demographic data. Insomnia data were collected through a self-reported questionnaire consisting of three questions. The positive and negative syndrome scale (PANSS) was used to measure psychopathological symptoms, while the repeatable battery for the assessment of neuropsychological status (RBANS) was used to measure cognitive performance.
Results: Of 957 Chinese patients with chronic schizophrenia 20.2% reported having insomnia (193/957). Male patients (107/630, 17.0%) had a lower rate of insomnia than female patients (86/327, 26.3%) (x2 = 11.60, p = 0.001). Patients with insomnia exhibited significantly higher PANSS total score and positive symptom, negative symptom, and general psychopathology scores, but significantly lower RBANS total score, language, attention and delayed memory scores compared to patients without insomnia (all p < 0.05). Logistic regression analysis showed that female sex, high PANSS total score and the use of diazepam were independently associated with insomnia (all p < 0.05).
Conclusions: Insomnia is relatively common in Chinese patients with chronic schizophrenia. Some demographic data and clinical symptoms are associated with insomnia. Patients with schizophrenia and insomnia perform poorly on cognition tests suggesting that insomnia and cognitive function are closely related in patients with schizophrenia.
Keywords: Clinical symptom; Cognitive performance; Insomnia; Schizophrenia.
© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.