Exploring the relationship between work performance and nonrestorative sleep among daytime workers with and without insomnia symptoms.

Objective: Insomnia and nonrestorative sleep are associated with presenteeism, which is an indicator of work performance and a predictor of absenteeism. However, the mechanisms by which insomnia symptoms and nonrestorative sleep are associated with presenteeism remain unclear.

Methods: This study included 1093 daytime workers categorized into four groups: the combination group, defined as having both insomnia symptoms and nonrestorative sleep; the nonrestorative sleep group, defined as having only nonrestorative sleep; the insomnia group, defined as having only insomnia symptoms; and the healthy group, defined as having no sleep complaints. They completed self-report questionnaires on insomnia symptoms, nonrestorative sleep, and presenteeism.

Results: The marginal effects of logistic regression analysis estimated that the probability of presenteeism in the combination group was higher by 42, 29, and 28 % compared with the healthy, insomnia, and nonrestorative sleep groups, respectively. The probability of presenteeism was 15 % higher in the nonrestorative sleep group and 13 % higher in the insomnia group than in the healthy group. Network analysis determined that a bad mood upon waking-up, lack of readiness to start the day upon waking-up, low mental alertness upon waking-up, daytime dysfunction, low well-being, and poor sleep quality were associated with presenteeism in the combination group. A feeling of tiredness upon waking-up was associated with presenteeism in the nonrestorative sleep group. Grouchiness upon waking-up was associated with presenteeism in the insomnia group.

Conclusion: When addressing presenteeism, the feeling of restfulness upon waking-up and during daytime activities should be considered, rather than just nocturnal sleep.