Treatment of chronic primary sleep onset insomnia with Kundalini Yoga: a randomized controlled trial with active sleep hygiene comparison

STUDY OBJECTIVES: Prior studies have suggested a benefit of yoga for alleviating sleep disturbance; however, many studies have had methodological limitations. This trial study aimed to extend that literature by including an active sleep hygiene (SH) comparison. METHODS: Participants aged 25-59 with a primary complaint of sleep onset insomnia lasting at least six months were block randomized to 8-week Kundalini Yoga or SH intervention, both consisting of initial 60-minute instruction and weekly check-ins. Daily sleep diaries and questionnaires were collected at baseline, throughout intervention, and at 6-month follow-up. Data were analyzed using linear mixed models (N=20 in each group). RESULTS: Participant ratings of the interventions did not significantly differ. SH improved several diary and questionnaire outcomes, however, yoga resulted in even greater improvements corresponding to medium-to-large between-group effect sizes. Total sleep time increased progressively across yoga treatment (d=0.95, p=.002), concurrent with increased sleep efficiency (SE; d=1.36, p<.001) and decreased sleep onset latency (SOL; d=-1.16, p<.001), but without changes in pre-sleep arousal (d=-0.30, p=.59). Remission rates were also higher for yoga compared to SH, with ≥80% of yoga participants reporting average SOL<30 minutes and SE>80% at 6-month follow-up. For over 50% of yoga participants, the insomnia severity index decreased by at least 8 points at end of treatment and follow-up. CONCLUSIONS: Yoga, taught in a self-care framework with minimal instructor burden, was associated with self-reported improvements above and beyond an active sleep hygiene comparison, sustained at 6-month follow-up. Follow-up studies are needed to assess actigraphy and polysomnography outcomes, as well as possible mechanisms of change. CLINICAL TRIAL REGISTRATION: Yoga as a Treatment for Insomnia (ClinicalTrials.gov, NCT00033865).