Feasibility and preliminary efficacy of online-delivered paradoxical intention therapy among adults with insomnia symptoms and high sleep effort

The aim of this study was to determine the feasibility and preliminary efficacy of online-delivered paradoxical intention therapy (PI) among adults with insomnia symptoms and high sleep effort. A two-arm randomised controlled trial was conducted. Twenty-six adults (18-54 years) were randomly allocated to receive either PI (n= 13) or sleep hygiene instructions (n= 13). PI sessions were delivered via the Internet across two hour-long sessions over two weeks whereas sleep hygiene instructions sessions were one-off. Participants completed 5 consecutive days of wrist actigraphy and sleep diary, the Glasgow Sleep Effort Scale (GSES), Pittsburgh Sleep Quality Index (PSQI) and Patient Health Questionnaire (PHQ-9) at baseline, post-intervention (2 weeks) and follow-up (1 month). Thirtyfive adults of the 46 recruited (76%) presented with insomnia symptoms and high sleep effort. The randomised participants who persisted with the study (n= 24) showed good adherence (85%-100%) throughout the intervention and follow-up periods. Significant reductions were observed on the GSES indicating the role of PI in reducing sleep effort. Findings also show that PI significantly improved self-reported sleep parameters (sleep onset latency, wake after sleep onset, sleep efficiency), and sleep quality measured by PSQI, yielding moderate to large effect sizes. Preliminary findings indicate that PI is a feasible, standalone psychological intervention for insomnia symptoms that can be administered successfully via the Internet. Future trials are needed to address the sustained efficacy of online PI on both objective and self-reported sleep quality, sleep effort and depression outcomes.