Abstract
BACKGROUND: Night shift work and poor sleep quality are gradually becoming more prevalent in modern society. Nevertheless, there have been limited studies assessing the association between night shift work, sleep behaviors, and risk of epilepsy. The aim of our study was to ascertain whether a positive association exists between night shift work, sleep quality, sleep behaviors, and risk of epilepsy. METHODS: Our study included a total of over 270,000 individuals with or without epilepsy from the UK Biobank, followed up over a period of 13.5 years. Information on current night shift work and major sleep behaviors was also obtained. We used Cox proportional hazard models to assess the association between night shift work, sleep quality, sleep behaviors, and the risk of epilepsy after adjusting for multiple variables. RESULTS: Night shift work was positively associated with a higher risk of epilepsy (P for trend = 0.059). There was a gradual increase in epilepsy risk from 'never/rarely' to 'usual/permanent' night shifts, with 'usual/permanent' night shifts work presenting the highest risk [hazard ratio (HR) 1.29, 95% confidence interval (CI) 1.01-1.65). Additionally, there was a significant association between sleep quality and risk of epilepsy (P < 0.001). Among the five major sleep behaviors, sleep duration (< 7 or > 8 h/day), frequent insomnia, and daytime sleepiness were significantly associated with a higher risk of epilepsy (HR 1.19, 95% CI 1.11-1.28; HR 1.19, 95% CI 1.09-1.30; HR 1.46, 95% CI 1.24-1.72, respectively). Furthermore, sleep duration exhibited a 'U-shaped' association with epilepsy risk. Nevertheless, no significant association was found between sleep chronotype and snoring and the risk of incident epilepsy (HR 1.04, 95% CI 0.96-1.12; HR 0.96, 95% CI 0.89-1.04). CONCLUSIONS: 'Usual/permanent' night shifts and poor sleep quality were positively associated with a greater risk of incident epilepsy. Major sleep behaviors, including unhealthy sleep duration (< 7 or > 8 h/day), frequent insomnia, and daytime sleepiness, also tended to increase the risk of epilepsy.