SHIFT WORK DISORDER - myCME.com

Shift-work disordermoderate caffeine intake has not been specifically assessedamong individuals with SWD.Other pharmacologic options for SWDAdministration of the sleep-mediating hormone melatonincan promote daytime sleep. 60 However, whilesome studies have reported that melatonin is helpfulfor inducing daytime sleep in simulated and real-worldshift-work conditions, 61-64 others have failed to demonstrateany objective or subjective benefit. 65 Single dosesof melatonin taken before the required sleep period insimulated shift-work studies of healthy subjects havebeen shown to decrease sleep latency and increase sleepduration. 62 Melatonin may be most beneficial as part ofa phase-advancing program to support individuals inadjusting to night-shift work rather than as a chronictherapy for SWD. 61,63,64,66Hypnosedatives, or sleep-promoting agents, takenbefore required sleep periods have also been evaluatedin simulated shift-work conditions. Zolpidem, zopiclone,triazolam, and temazepam have all been shownto increase sleep duration during the day and to improvewakefulness during the night shift. 52,67-70 Only zopiclonehas been evaluated among shift workers. 70 In a study of12 healthy male volunteers working 12-hour shifts, a singledose of zopiclone 7.5 mg taken before the requiredsleep period significantly improved sleep at night, butthis improvement did not reach statistical significancewhen the required sleep period was during the day. Nostudies of hypnosedatives have been conducted amongindividuals with SWD. The greater effect of hypnotics onnight-time sleep suggests that they are less efficacious atimproving disturbed sleep when given out of phase withthe usual sleep period.SummaryAlthough few interventions have been studied specificallyamong individuals with SWD, there are a range ofpractical steps that clinicians can offer to relieve its adverseeffects and to reduce a patient’s risk of experiencingthe potentially fatal consequences of this disorder.Appropriate interventions include steps to improvesleep hygiene, and evaluation and appropriate referralfor comorbid conditions, with particular emphasis oncomorbid sleep disorders. Strategies to promote adaptationto the required sleep/wake cycle should also beimplemented. These can include bright light therapy(before or during a night shift), reduction of exposure todaylight on the commute home from work, and/or medicationwith melatonin before a required sleep period,or combinations thereof. 32,34,36,66 These strategies haveproved useful among shift workers in general, and furtherinvestigation of such strategies would be valuableamong those with SWD. Steps to improve shift schedules(eg, the use of clockwise-rotating shifts and avoidingshifts longer than 12 hours), and measures to improveshift-work conditions, such as bright light exposure andappropriately timed naps, may also be helpful.The wakefulness-promoting agents modafinil andarmodafinil are the only interventions with FDA approvalfor use in patients with SWD and have been evaluatedspecifically among individuals with ES associated withSWD. These agents have been proven to reduce ES duringthe work period, with associated benefits in terms ofa reduced incidence of accidents or near misses duringthe commute home. Initiation of wakefulness-promotingtherapy should be considered early in the managementof individuals with SWD.Future research should focus on the potential of interventionsknown to promote wakefulness or sleep specificallyamong individuals with SWD. In the meantime,clinicians caring for individuals with SWD should developindividualized management strategies that incorporateboth nonpharmacologic interventions and pharmacologictherapies, such as a wakefulness-promotingagent before the work period with or without a sleeppromotingagent before the required sleep period. nReferences1. Morgenthaler TI, Lee-Chiong T, Alessi C, et al.Practice parameters for the clinical evaluationand treatment of circadian rhythm sleep disorders.Sleep. 2007;30:1445-1459.2. Sack RL, Auckley D, Auger RR, et al. 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J Clin SleepMed. 2007;3:519-528.9. Dinges DF, Pack F, Williams K, et al. Cumulativesleepiness, mood disturbance, and psychomotorvigilance performance decrements during aweek of sleep restricted to 4–5 hours per night.Sleep. 1997;20:267-277.10. Van Dongen HP, Maislin G, Mullington JM, et al.The cumulative cost of additional wakefulness:S30 January 2010 / Vol 59, No 1 • Supplement to The Journal of Family Practice