Insomnia in epilepsy is associated with nocturnal seizures and anxiety

Purpose: The purpose of this study was to identify the factors associated with insomnia in patients with epilepsy (PWE) and provide evidence for clinical prevention and treatment.

Methods: PWE who visited our epilepsy clinic from December 2021 to December 2022 were enrolled in our study. All participants completed the Insomnia Severity Index (ISI), Epworth Sleepiness Scale (ESS), Self-rating Anxiety Scale (SAS), and Self-rating Depression Scale (SDS). Based on their ISI scores, they were categorized into two groups: PWE with insomnia (ISI score ≥ 10) and PWE without insomnia (ISI score < 10). Univariate analysis and stepwise logistic regression analysis were conducted to identify the factors associated with insomnia in PWE.

Results: A total of 196 Chinese PWE were recruited in this study(men, 39.8 %). Of these, 39 PWE(19.9 %) had insomnia.The incidence of nocturnal seizures (43.6 %vs19.7 %), depression (46.2 %vs9.6 %), anxiety (59.0 %vs11.5 %), and excessive daytime sleepiness(EDS,28.2 %vs5.7 %) in PWE with insomnia were significantly higher than in those without insomnia(all p＜0.01). Univariate regression analysis showed that seizures greater than or equal to once per month, nocturnal seizures, anxiety, depression, and EDS may associate with insomnia in PWE(all p＜0.05). Stepwise logistic regression analysis demonstrated that nocturnal seizures (OR = 2.611,95 % CI 1.040-6.478, P = 0.038) and anxiety (mild OR = 4.830,95 %CI 1.741-13.186, P = 0.002;moderate OR = 24.239,95 %CI 4.719-183.935, P＜0.001; severe OR = 37.653,95 %CI 4.931-782.741, P = 0.002) were independently associated with insomnia in PWE.

Conclusion: PWE with insomnia are more likely to experience depression and EDS. Nocturnal seizures and anxiety are identified as independent factors associated with insomnia in PWE. Furthermore, Anxiety has a greater impact on insomnia in PWE and the likelihood of insomnia has increased significantly with the aggravation of anxiety levels.