Contribution of dysfunctional sleep-related cognitions on insomnia severity: a network perspective.

STUDY OBJECTIVES: Various models of insomnia stress the role of cognitive components, such as dysfunctional sleep-related beliefs, in maintenance and exacerbation of insomnia. This study aimed to employ network analysis to identify the particular beliefs that are central and have strong associations with insomnia severity. In addition, we aimed to employ a relative importance network to map out predictive pathways between types of dysfunctional beliefs and insomnia severity.

METHODS: This study was a retrospective study, with data collected from 219 patients suffering from insomnia. Patients' responses to Dysfunctional Beliefs about Sleep scale-16 (DBAS-16) and Insomnia Severity Index (ISI) were collected. All network analyses were performed using R Studio to produce three networks: 1) DBAS-16 network; 2) DBAS-16 and ISI network; 3) relative importance network containing DBAS-16 subscales and ISI.

RESULTS: Beliefs reflecting overestimation of negative consequences of sleep (e.g. 'insomnia is ruining life'), loss of ability (e.g. 'worry about losing abilities to sleep'), and unpredictability (e.g. 'can't predict sleep quality') were identified as most central and strongly associated with insomnia severity. Worry/helplessness about insomnia had the largest predictive value on insomnia severity, and also acted as a mediator between other subscales and insomnia severity.

CONCLUSIONS: The results of our study suggest that overestimation of negative consequences, loss of ability, and unpredictability are key beliefs that exacerbate and maintain insomnia, thus supporting existing cognitive models of insomnia.