Pharmacological Interventions for Sleepiness and Sleep Disturbances Caused by Shift Work

Abstract

BACKGROUND: Shift work results in sleep-wake disturbances, which cause sleepiness during night shifts and reduce sleep length and quality in daytime sleep after the night shift. In its serious form it is also called shift work sleep disorder. Various pharmacological products are used to ameliorate symptoms of sleepiness or poor sleep length and quality. OBJECTIVES: To evaluate the effects of pharmacological interventions to reduce sleepiness or to improve alertness at work and decrease sleep disturbances whilst off work, or both, in workers undertaking shift work. METHODS: Search methods: We searched CENTRAL, MEDLINE, EMBASE, PubMed and PsycINFO up to 20 September 2013 and ClinicalTrials.gov up to July 2013. We also screened reference lists of included trials and relevant reviews. Selection criteria: We included all eligible randomised controlled trials (RCTs), including cross-over RCTs, of pharmacological products among workers who were engaged in shift work (including night shifts) in their present jobs and who may or may not have had sleep problems. Primary outcomes were sleep length and sleep quality while off work, alertness and sleepiness, or fatigue at work. Data collection and analysis: Two authors independently selected studies, extracted data and assessed risk of bias in included trials. We performed meta-analyses where appropriate. MAIN RESULTS: We included 15 randomised placebo-controlled trials with 718 participants. Nine trials evaluated the effect of melatonin and two the effect of hypnotics for improving sleep problems. One trial assessed the effect of modafinil, two of armodafinil and one examined caffeine plus naps to decrease sleepiness or to increase alertness. Melatonin (1 to 10 mg) after the night shift may increase sleep length during daytime sleep (mean difference, MD, 24 minutes, 95% confidence interval, CI, 9.8 to 38.9; seven trials, 263 participants, low quality evidence) and night-time sleep (MD 17 minutes, 95% CI 3.71 to 30.22; three trials, 234 participants, low quality evidence) compared to placebo. We did not find a dose-response effect. Melatonin may lead to similar sleep latency times as placebo (MD 0.37minutes, 95% CI-1.55 to 2.29; five trials, 74 participants, low quality evidence). Hypnotic medication, zopiclone, did not result in significantly longer daytime sleep length compared to placebo in one low quality trial and we could not use the data from the study on lormetazepam. Armodafinil taken before the night shift probably reduces sleepiness by one point on the Karolinska Sleepiness Scale (KSS) (MD-0.99, 95% CI-1.32 to-0.67; range 1 to 10; two trials, 572 participants, moderate quality evidence) and increases alertness by 50 ms in a simple reaction time test (MD-50.0, 95% CI-85.5 to-15.5) at three months' follow-up in shift work sleep disorder patients. Modafinil probably has similar effects on sleepiness (KSS) (MD-0.90, 95% CI-1.45 to-0.35; one trial, 183 participants , moderate quality evidence) and alertness in the psychomotor vigilance test in the same patient group. P...

Health consequences of shift work and insufficient sleep

“…131 132 A repeated finding is that people with the long PER3 polymorphism (PER3 −/5 ) have a morning preference, and night workers with this polymorphism are more fatigued and tend to have earlier circadian phases, indicating a lack of adaptation to night work. 72 132 the effect of caffeine and other alertness enhancing drugs (such as modafinil) in mitigating sleepiness during night shifts, 135 a systematic review on studies of simulated shift work showed that caffeine might be an effective intervention for improving alertness in shift workers. 112 The benefits of forward rotating shift systems for sleep were also found in an earlier systematic review, whereas insufficient evidence existed to support that long (≥12 h) shifts and timing of shifts influenced duration and quality of sleep.…”

“…134 A systematic review published in 2014 (based on 15 randomised, placebo controlled trials) found low quality evidence for melatonin being a countermeasure against sleep problems after a night shift. 135 No conclusions could be drawn about the effectiveness of hypnotics against sleep problems in relation to night work, as too few studies were identified. 135 Although only weak evidence exists for Box 2 | Organisational and individual countermeasures* Mitigation of the health and safety risks associated with shift work involves: • Shift schedules should minimise insufficient sleep and circadian disruption and be characterised by forward and rapid rotation, have a minimum of 11 hours of recovery time between shifts, and avoid long weekly working hours (<60 hours) and work shifts (<10 hours) • Offer shift workers a high degree of individual working time control and regulate excessive working hours (including overtime and double work) • Regularly screen (and offer treatment) for clinical sleep disorders among shift workers • Educate shift workers on individual strategies that can mitigate acute sleep and fatigue problems and protect long term health: -Knowledge on sleep hygiene; how to prioritise sleep and recovery before, during, and after work periods; and napping before and during night shifts -Knowledge of how to use caffeine and bright light exposure at night to promote adaptation and performance -A healthy lifestyle for shift workers includes a healthy diet, limited night time eating, physical activity, and avoidance of smoking and excessive alcohol intake *The guidelines for countermeasures are mainly based on narrative reviews shift and night work.…”

The impact of meal timing on performance, sleepiness, gastric upset, and hunger during simulated night shift

“…There are currently more than 1.5 million shift workers in Australia1 ) and 29% of workers in the United States, do not work regular daytime shifts, with numbers likely to rise with increasing demand by companies to extend working hours2 ) . Shift workers are often required to work throughout the night, for consecutive nights, when circadian processes typically promote sleep3 ) .…”

Optimising sleep for night shifts

“…Doses of 4 mg/kg taken eight hours before intended sleep do not appear to disrupt subsequent sleep 20. There is moderate quality evidence that other stimulant medications such as armodafinil and modafinil are effective, with three randomised controlled trials, including a total of 755 shift workers, finding that these drugs reduced sleepiness during the night shift, compared with placebo 9. However, both drugs have been associated with severe skin reactions, and their long term consequences have not been well established.…”