No Association Between Insomnia Severity, and Discrepancy Between Desired Time in Bed and Desired Total Sleep Time Among Shift-Working Nursing Professionals

Background and Objective This study aimed to explore whether the discrepancy between a patient’s desired time in bed and desired total sleep time (DBST index) can be used as a tool to assess the insomnia severity of shift-working nursing professionals.Methods Two studies were conducted during two different times among two groups of shiftworking nursing professionals working in COVID-19 inpatient wards (study I), or nurses who witnessed patient death during the previous 2 years (study II), using a single voluntary survey. The survey was completed by a total of 366 participants: 226 in the first study, and 140 in the second. Participants’ age, sex, marital status, and past psychiatric history were collected. In addition to questions regarding the DBST index, the Glasgow Sleep Effort Scale (GSES), Dysfunctional Beliefs about Sleep-2 items (DBS-2), and the Insomnia Severity Index (ISI) were assessed.Results In both studies, the DBST index did not reflect insomnia severity, preoccupation with sleep, or dysfunctional beliefs about sleep in the linear regression analysis. In addition, ISI was expected by GSES (β = 0.67 in study I, β = 0.62 in study II, all p < 0.001) and DBS-2 (β = 0.16 in study II, p = 0.020), but not by the DBST index.Conclusions It was observed that the DBST index was not significantly associated with insomnia severity, preoccupation with sleep, or dysfunctional beliefs about sleep in two studies done among shift working-nursing professionals.