Effect of Esketamine on Cognitive Behavioral Therapy for Insomnia Adherence in Patients with Comorbid Insomnia and Depression

This retrospective cohort study in China (n=184; exposure group 92, control group 92) examined the effect of esketamine on adherence to cognitive behavioural therapy for insomnia (CBT-I) in patients with comorbid insomnia and depression. The study compared an exposure group and a control group, although no active intervention was administered in either group, consistent with the observational design. The primary outcome was adherence to behavioural strategies, with assessment of whether esketamine exposure was associated with better engagement in CBT-I. Secondary outcomes included bedtime variability, wake-up time variability, CBT-I completion rate, Insomnia Severity Index scores, response and remission rates, Hospital Anxiety and Depression Scale scores, and equivalent benzodiazepine dose. The trial included adults aged 18 to 75 years and was sponsored by Shanghai Fourth People’s Hospital. As a retrospective study, the protocol did not specify a treatment phase or prospective dosing schedule, and outcome timepoints were not detailed in the source record.