Refresh. Restriction For Reorganising Sleep Habit: A randomised controlled trial of simplified sleep restriction for primary insomnia in the primary care setting

Abstract

Rationale: Insomnia is a common health problem for patients in primary care. A literature review conducted by the author concluded that cognitive behavioural therapy for insomnia (CBT-I) is effective but its use has been limited by the time and expense required for delivery. Sleep restriction, or restricting the time in bed, is one component of CBT-I, which could be delivered as a brief intervention during primary care consultations. A systematic review of sleep restriction as a stand-alone treatment for insomnia showed some benefit, but concluded that more evidence was required. Objective: To assess the effectiveness of simplified sleep restriction to improve sleep in primary insomnia. Design, Setting, and Participants: A randomised controlled trial involving adult patients with persistent primary insomnia recruited from general practice clinics in Auckland, New Zealand between 2009 and 2012. Intervention: Intervention patients received 20 minutes of sleep hygiene advice and “simplified sleep restriction” instructions at an initial visit with a general practitioner and 14 minutes of advice and a “sleep self-adjustment algorithm” at two weeks. Control patients received sleep hygiene advice alone at both visits. Main outcomes: The primary outcomes were change in sleep quality at six months as measured by the Pittsburgh Sleep Quality Index (PSQI), the Insomnia Severity Index (ISI), and sleep efficiency. Proportion reaching a pre-defined “treatment response” was calculated using PSQI and sleep efficiency. Secondary outcomes included sleepiness, fatigue, sleep-onset latency, wakefulness after sleep onset, total sleep time, depression and anxiety. Potential adverse events (excessive sleepiness, accidents, hospitalisations, physiological parameters) were monitored. Results: Ninety-seven patients were recruited and 94 (97%) completed the study. Simplified sleep restriction led to significantly improved PSQI scores (6.2 vs 8.4, p < 0.001), ISI scores (8.6 vs 11.1, p = 0.001); sleep efficiency (difference between mean changes 2.2%, p = 0.006) and sleep onset latency (difference between mean changes -6.1 minutes, p = 0.04) as measured by actigraphy; and a reduction in fatigue (difference between mean changes -2.3 units, p = 0.04) compared with control. Simplified sleep restriction also produced higher rates of “treatment response” (67% [28/42] vs 41% [20/49]), with an adjusted odds ratio of 2.7 (95% CI, 1.1 to 6.5; p = 0.03). There were no significant differences in other outcomes or adverse effects. Conclusions and Relevance: Simplified sleep restriction is a practical, effective intervention for chronic insomnia in adults suitable for the primary care setting.