Kim Sohyeong, Cho Eulah, Choi Hayun, Chung Seockhoon
University of Ulsan College of Medicine, Ulsan, Republic of Korea.
Department of Psychiatry, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
Psychiatry Investig. 2024 Sep;21(9):971-978. doi: 10.30773/pi.2024.0043. Epub 2024 Aug 8.
This study investigated whether the discrepancy between desired time in bed and desired total sleep time (DBST) index could be a meaningful indicator for assessing insomnia severity in a clinical sample of patients with insomnia. Furthermore, we sought to identify the mediators of the association between DBST and insomnia severity in individuals with insomnia.
We collected the medical records of 127 patients with insomnia. Each participant's DBST index was calculated using sleep indices, including time and duration variables. Psychological symptoms were investigated using the Insomnia Severity Index (ISI), Patients Health Questionnaire-9 items (PHQ-9), Generalized Anxiety Disorder-7, Dysfunctional Beliefs and Attitudes about Sleep-16 items (DBAS-16), and Epworth Sleepiness Scale.
The DBST index was significantly correlated with the ISI (r=0.20, p<0.05), desired total sleep time (r=-0.52, p<0.001), and desired time in bed (r=0.32, p<0.01). Linear regression analysis revealed that insomnia severity was associated with age (β=-0.18, p=0.018), DBST (β=0.23, p=0.003), PHQ-9 (β=0.23, p=0.031), and DBAS-16 (β=0.42, p<0.001). The DBST directly influenced insomnia severity, although indirect effects of mediators were not significant.
The DBST index directly influenced insomnia severity regardless of the mediating effects of psychological factors among a clinical sample of patients with insomnia. This finding implies that the DBST index can be a simple measure of insomnia severity, even among patients with insomnia.
本研究调查了期望卧床时间与期望总睡眠时间之间的差异（DBST）指数是否可作为评估失眠症临床样本中失眠严重程度的有意义指标。此外，我们试图确定失眠症患者中DBST与失眠严重程度之间关联的中介因素。
我们收集了127例失眠症患者的病历。使用包括时间和时长变量在内的睡眠指数计算每位参与者的DBST指数。使用失眠严重程度指数（ISI）、患者健康问卷9项（PHQ - 9）、广泛性焦虑障碍7项、睡眠功能失调信念与态度16项（DBAS - 16）和爱泼沃斯嗜睡量表调查心理症状。
DBST指数与ISI显著相关（r = 0.20，p < 0.05）、期望总睡眠时间（r = -0.52，p < 0.001）和期望卧床时间（r = 0.32，p < 0.01）。线性回归分析显示，失眠严重程度与年龄（β = -0.18，p = 0.018）、DBST（β = 0.23，p = 0.003）、PHQ - 9（β = 0.23，p = 0.031）和DBAS - 16（β = 0.42，p < 0.001）相关。DBST直接影响失眠严重程度，尽管中介因素的间接影响不显著。
在失眠症临床样本中，无论心理因素的中介作用如何，DBST指数都直接影响失眠严重程度。这一发现意味着DBST指数可作为一种简单的失眠严重程度测量指标，即使在失眠症患者中也是如此。
