60 Neuropsychiatric Medicine C LINICAL P SYCHIATRY N EWS • February 2005 Biologic Rhythms Are and Only Slightly Key in Assessing Helpful to Night Shift Workers BY NICHOLAS MULCAHY prove across successive night shifts—as has Aligning circadian rhythms can maximize Contributing Writer been found in some laboratory studies. Peo- ple are not getting used to things [on the patients’ performance in workplace, on road. P HILADELPHIA — The combination of night shift],” Dr. Schweitzer said. caffeine and evening naps has only modest But some evidence indicated that the caf- BY HEIDI SPLETE back as much as 4 hours of . positive effects on performance and subjec- feine and naps did help somewhat. Senior Writer As a result, naps should be seen as a tive sleepiness of night shift workers, Paula Only the placebo group had a worsening drug-free intervention for sleepiness, Schweitzer, Ph.D., reported at the annual of RT10 from shift start to shift end. Addi- A RLINGTON, VA . — Approximate- and certain conditions make them meeting of the Associated Professional tionally, at shift end, the placebo group’s ly 40 million Americans are affected by more effective. Sleep Societies. RT10 was worse than that of the caf- sleep disorders, and more than 100,000 Silence and darkness are key for qual- In a rare field study of night shift workers, feine/ treatment group. motor vehicle accidents per year are ity naps, as is elevation of the feet, and 39 participants (28 males; mean age 33 years) The study also evaluated PVT lapses, sleep related, the hands and completed a 4-consecutive-night crossover which are unacceptably long delays in PVT Teodor Posto- feet should be study comparing two conditions: an evening reaction time. Again, the nap/caffeine lache, M.D., said comfortably nap prior to the night shift on the first 2 group outperformed the placebo group. at the annual A 1-hour nap has warm. For some nights plus caffeine 300 mg on all 4 nights and PVT lapse frequency increased from shift conference of been shown to pay people, sooth- placebo without napping on all 4 nights. start to end for the placebo group, with no the Academy of back as much as ing music facili- Three times during each night (start of change for the treatment group. But both Organizational 4 hours of sleep tates a nap, ac- shift, midway, and end of shift), partici- the placebo and treatment groups had an in- and Occupation- debt. cording to Dr. pants completed a 15-minute psychomotor crease in lapse frequency across nights 1-4, al Psychiatry. Postolache. vigilance task (PVT) using a handheld PVT which, in effect, was further proof of Dr. An under- DR. POSTOLACHE One caveat, electronic device that measured the sub- Schweitzer’s observation that workers are standing of the however, is a ject’s reaction times to tasks. The study sub- not getting accustomed to night . biologic rhythms that are associated “terrible drop in vigilance” immediate- jects also completed subjective sleepiness Subjective sleepiness as measured by the with disruptive sleep gives psychiatrists ly following a nap, he said. Known as and mood tests three times a night, said Dr. Karolinska Sleepiness Scale also indicated additional perspectives on occupation- sleep inertia, this period lasts an average Schweitzer, associate director of the Sleep some benefit of the caffeine and naps. The al problems. of 15-20 minutes, but can last up to 2 Medicine and Research Center at St. Luke’s placebo group showed increased sleepiness Inadequate sleep, for example, could hours in rare cases. Hospital, St. Louis. at shift end, but the treatment group did trigger a manic episode in a bipolar dis- In fact, studies have shown that hos- RT10, or the reaction time of the slowest not. There was no change in sleepiness rat- order patient, which could lead to a pital residents are prone to making ma- 10% of the PVT responses, worsened across ings across nights 1-4, Dr. Schweitzer said. confrontation at work and the loss of a jor mistakes during the first 15-20 min- nights 1-4 for both the nap/caffeine treat- Actigraph-estimated total sleep time for job, said Dr. Postolache of the Univer- utes after a nap. ment group and the placebo group. daytime sleep did not differ between the sity of Maryland, Baltimore. From an occupational standpoint, “Alertness and performance did not im- two groups. ■ Biologic rhythms are based on the those people who take naps at work movement of the earth and sun. They should be given simple tasks to do are internally generated—they occur in when they first awaken. anticipation of environmental condi- “Those 20 minutes after waking up Modafinil Still Effective for Sleep tions—and circadian rhythms are the bi- should not be a time when someone ologic rhythms based on a 24-hour cy- should be required to make major life or cle, explained Dr. Postolache, who business decisions,” Dr. Postolache said. Apnea After 17 Weeks of Therapy specializes in consulting with travelers and athletes about aligning circadian Light boxes BY NICHOLAS MULCAHY worth score is indicative of improved wake- rhythms to maximize physical and men- Available in various forms and sizes, Contributing Writer fulness, and reduction of 4 points is consid- tal performance on arrival. they help travelers shift their biologic ered a response to treatment. No statistical dif- “One of the major roles of the cir- rhythms to function at their best. Light P HILADELPHIA — Modafinil in patients ference was found between the Epworth cadian system is to consolidate periods boxes also may ease the discomfort of with obstructive and excessive scores before and after conventional treat- of wakefulness and sleep,” as opposed shift workers who are changing from a daytime sleepiness despite positive airway ment, but the change after modafinil treat- to sleeping and waking several times night shift to a day shift. pressure therapy was effective in improving ment was significant, Dr. Moralejo said. during the day, he said. As people be- wakefulness for at least 17 weeks in a small The improvement in Epworth Sleepiness come sleepier, the circadian system study presented at the annual meeting of Scale score was similar whether patients sends signals to maintain alertness. It is secreted in the dark, promotes the Associated Professional Sleep Societies. were on modafinil for more than or less The circadian system raises the sleepiness, and has been used to mea- Previous studies of the wakefulness drug than 12 weeks. The average duration of threshold for sleep in the evening, sure circadian rhythms. An onset of and (OSA) had been treatment was 17 weeks (range 1-40). when sleepiness is at a maximum, and melatonin secretion occurs in the limited to 12 weeks, Juan Moralejo, M.D., On univariate analysis, factors associated lowers that threshold in the early evening, followed by a rapid rise and reported. with response to modafinil were higher Ep- morning hours. then a plateau during the night. “In our study population, modafinil was worth Sleepiness Scale score at diagnosis, However, biologic rhythms vary with The duration of melatonin secre- more likely to be effective in the elderly and higher Epworth score while on conven- the individual, and laboratory research tion lengthens when the nights are those with high Epworth Sleepiness Scale tional therapy, and male gender, said Dr. has shown that individual biologic long and shrinks when nights are short, scores at the time of diagnosis” of daytime Moralejo, who has no affiliation with rhythms impact cognitive performance. he said. sleepiness, said Dr. Moralejo, a pulmonary Cephalon, maker of Provigil. But on mul- Psychiatrists—especially occupational Evidence for melatonin as a fellow at Graduate Hospital, tivariate analysis, a high Epworth score at di- psychiatrists—should keep this in mind. agent is weak, but some evidence sup- Philadelphia. agnosis of OSA and increasing age corre- Some people are “short sleepers” ports its use to reduce . A The study sample consisted of 22 pa- lated best with response to modafinil. whose cognition does not improve if Cochrane Review (Cochrane Database tients (13 males and 9 females), mean age The average dosage of modafinil was they sleep more than 7 or 8 hours, Syst. Rev. 2002;2:CD001520) suggested 53.9 years. Of the 18 patients receiving 227.3 mg once daily (range 100-800). No sig- while others are “long sleepers” who that melatonin can relieve jet lag in peo- “conventional treatment,” 9 were using con- nificant side effects were documented. truly need 10 hours of sleep to function ple with a history of jet lag who are fly- tinuous positive airway pressure, 8 were us- Epworth Sleepiness Scale scores at the di- at their best, Dr. Postolache said. Strate- ing east (CLINICAL PSYCHIATRY NEWS, ing bilevel positive airway pressure, and 1 agnosis of OSA and after treatment with gies that are aimed at helping sleep-dis- October 2004, p. 63). was using a dental device. At the time of the conventional modalities were obtained from turbed patients get in tune with their bi- Side effects of melatonin include survey, four patients were not using any the patients’ records. A telephone survey ologic rhythms include taking naps and drowsiness, decreased , GI conventional treatment for OSA. was conducted and included questions about using light boxes and melatonin. symptoms, and possible antigonadal The mean Epworth Sleepiness Scale score patients’ demographics, modafinil treat- steroid effects, and it should be used was 15.9 at diagnosis, 13.6 after treatment with ment, and type of ongoing conventional Naps on an as-needed basis, Dr. Postolache conventional modalities, and 8.9 after treat- treatment for OSA as well as patient com- A 1-hour nap has been shown to pay noted. ■ ment with modafinil (Provigil). A lower Ep- pliance with this treatment. ■