Analysis of the correlation between the degree of sleepiness and the therapeutic effect in patients with insomnia disorder treated with digital cognitive behavioral therapy.

Introduction: Some patients experience increased daytime sleepiness during early dCBT‑I, which may affect function and adherence. This study aimed to investigate daytime sleepiness during dCBT‑I, explore its influencing factors, and evaluate its predictive value for treatment efficacy. Methods: A retrospective analysis was conducted on 2271 insomnia patients treated at the sleep clinic of Hangzhou Seventh People's Hospital from November 2016 to January 2024. Daytime sleepiness and sleep quality were assessed using the Epworth Sleepiness Scale (ESS) and Pittsburgh Sleep Quality Index (PSQI). Results: ESS scores significantly increased at week 2, 4, and 6, peaking at week 2. Sex, medication use, snoring, and baseline ESS were significant influencing factors. Patients with early increased sleepiness showed greater PSQI reduction rates at subsequent follow‑ups. Univariate and multivariable linear regression confirmed that week 2 ESS exacerbation independently predicted higher PSQI reduction at weeks 4, 8, 12, and 16 (all p < 0.05). Discussion: Transient increased daytime sleepiness often occurs in the early stage of dCBT‑I, which is related to multiple factors and can serve as a predictor of subsequent treatment efficacy.