Purpose: The aim of this study was to examine psychological factors in insomnia and the association between psychological mechanisms and nighttime and daytime symptoms.
Methods: A cross-sectional examination in the general population was used. The study sample consisted of 1890 participants from the general population. The participants completed a survey on nighttime and daytime symptoms, health outcomes, and psychological factors.
Results: Relative to poor and normal sleepers, the insomnia group had higher scores on worry, beliefs, physiologic arousal, monitoring/attentional bias, and safety behaviors than the other two groups, and the poor sleepers exhibited a similar pattern relative to the normal sleepers. High total wake time was associated with more worry, physiologic arousal, and safety behaviors (26.3% variance), low sleep restoration with more worry, unhelpful beliefs, and monitoring/attentional bias (28.2% variance), and low sleep quality with higher scores on all the psychological mechanisms (35.8% variance). Elevated daytime symptoms were related to more unhelpful beliefs and monitoring/attentional bias (44.3% variance).
Conclusion: The findings indicate that psychological factors are linked to nighttime and daytime symptomatology in insomnia.