Delayed sleep phase syndrome: A placebo-controlled cross-over study on the effects of melatonin administered five hours before the individual dim light melatonin onset

Updates and confounding factors in delayed sleep-wake phase disorder

Delayed sleep-wake phase disorder (DSWPD) is a circadian rhythm sleep disorder characterised by a delay in the main sleep period, with patients experiencing difficulty getting to sleep and waking up at socially appropriate times. This often causes insomnia and compromised sleep, results in impairment to daytime function and is associated with a range of comorbidities. Besides interventions aimed at ameliorating symptoms, there is good evidence supporting successful phase advancement with bright light therapy or melatonin administration. However, no treatment to date addresses the tendency to phase delay, which is a common factor amongst the various contributing causes of DSWPD. Circadian phase markers such as core body temperature and circulating melatonin typically correlate well with sleep timing in healthy patients, but numerous variations exist in DSWPD patients that can make these unpredictable for use in diagnostics. There is also increasing evidence that, on top of problems with the circadian cycle, sleep homeostatic processes actually differ in DSWPD patients compared to controls. This naturally has ramifications for management but also for the current approach to the pathogenesis itself in which DSWPD is considered a purely circadian disorder. This review collates what is known on the causes and treatments of DSWPD, addresses the pitfalls in diagnosis and discusses the implications of current data on modified sleep homeostasis, making clinical recommendations and directing future research.

Melatonin as a Chronobiotic with Sleep-promoting Properties

The use of exogenous melatonin (exo-MEL) as a sleep-promoting drug has been under extensive debate due to the lack of consistency of its described effects. In this study, we conduct a systematic and comprehensive review of the literature on the chronobiotic, sleep-inducing, and overall sleep-promoting properties of exo-MEL. To this aim, we first describe the possible pharmacological mechanisms involved in the sleep-promoting properties and then report the corresponding effects of exo-MEL administration on clinical outcomes in: a) healthy subjects, b) circadian rhythm sleep disorders, c) primary insomnia. Timing of administration and doses of exo-MEL received particular attention in this work. The exo-MEL pharmacological effects are hereby interpreted in view of changes in the physiological properties and rhythmicity of endogenous melatonin. Finally, we discuss some translational implications for the personalized use of exo-MEL in the clinical practice.

A comparison of four methods to estimate dim light melatonin onset: a repeatability and agreement study

Dim light melatonin onset (DLMO) is considered the most reliable circadian phase marker in humans. However, the methods to calculate it are diverse, which limits the comparability between studies. Given the key role of DLMO to diagnose circadian rhythm sleep-wake disorders and determine the optimal timing of chronotherapies, the establishment of clear and validated guidelines on the methodology to assess DLMO is very important. We performed a repeatability study (n = 31) and an agreement study (n = 62) in healthy young adults with hourly blood samples collected under dim light conditions (<8 lux) during a chronobiological protocol. We assessed the repeatability of DLMO with three different methods (fixed threshold, dynamic threshold and hockey stick) across two nights and assessed agreement of each method with the mean visual estimation made by four chronobiologists. Analyses included Bland-Altman diagrams, intraclass correlation coefficients and equivalence tests. The repeatability of the four methods across two nights ranged from good to perfect. The agreement study highlighted that the hockey stick showed equivalent or superior performance (ICC: 0.95, mean difference with visual estimation: 5 min) in healthy subjects compared to the dynamic and fixed thresholds. Thanks to its objective nature, the hockey stick method may provide better estimates than the mean of the visual estimations of several raters. These findings suggest that the hockey stick method provides the most reliable estimate of DLMO within the tested methods and should be considered for use in future studies.

Assessment of dim light melatonin onset based on plasma and saliva samples

Melatonin (MELA) is a nocturnal hormone involved in the regulation of the circadian rhythm. MELA can be detected in plasma and saliva, and its salivary concentration strongly correlates with its plasma concentration. Dim light melatonin onset (DLMO) is considered to be the most accurate objective marker for assessing the circadian phase. The purpose of the study was to establish a method for the determination of MELA in plasma and saliva based on the liquid chromatography with tandem mass spectrometry (LC-MS/MS) and compare DLMO using both plasma and saliva matrices. The validation of the LC-MS/MS methods was performed in accordance with the European Medicines Agency (EMA) guideline. The study was conducted on a group of 21 volunteers, male and females, aged 26-54 years. Plasma and saliva were collected at five time points: between 20:00 and 00:00 hours. The MELA concentration was determined by the LC-MS/MS. The DLMO was considered as the point in time when MELA concentration exceeds 20 pg/mL in plasma and 7 pg/mL in saliva. The correlation coefficient between the plasma and salivary MELA concentration was r = 0.764 (p < .001). The ratio of the plasma/saliva MELA concentrations was 2.87. The mean time of the DLMO in the plasma was 21:30 ± 0:45 hours, and in the saliva was as follows: 21:34 ± 1:00 hours. The correlation between the DLMO, calculated based on the plasma and saliva MELA profiles, was r = 0.679 (p < .05). The determination of salivary MELA concentration using LC-MS/MS allows for the determination of the DLMO. Our method may be applied in clinical practice for the diagnosis and monitoring of circadian rhythm disorders.Abbreviations: CE: Collision Energy; CID: Collision-Induced Dissociation; DL: Desolvation Module; DLMO: Dim Light Melatonin Onset; EFSA: European Food Safety Authority; EMA: European Medicines Agency; ESI: electrospray ionization; HB: heat block; HPLC: high performance liquid chromatography; IS: internal standard; K₃EDTA: ethylenediaminetetraacetic acid tripotassium salt; LC-MS/MS: liquid chromatography with tandem mass spectrometry; LLE: liquid-liquid extraction; LLOQ: lower limit of quantification; MELA: melatonin; MELA-D₄: melatonin-d₄; MRM: multiple reaction monitoring; Q1: quadrupole 1; Q3: quadrupole 3; RE: relative error; RIA: radioimmunoassay; RSD: relative standard deviation; SD: standard deviation; ULOQ: upper limit of quantification.

Use of Nutraceutical Ingredient Combinations in the Management of Tension-Type Headaches with or without Sleep Disorders

Headache is the most common pain complaint in the pediatric population, with tension type headache (TTH) having a prevalence of 10–15% in children. Up to 70% of pediatric patients with chronic headache also experience sleep disruption, with a likely bidirectional relationship between headache and poor sleep. Treatment options include specific pharmacological approaches as well as non-pharmacological alternatives; nutraceuticals have the advantage of a relative lack of side effects. Exogenous melatonin has been shown to be useful and safe in improving sleep-wake cycles and quality of sleep in children, helping to regulate the circadian rhythm, with a secondary positive impact on headache. Supplementation with other nutraceutical ingredients, such as tryptophan, magnesium, and B vitamins, can have significant additional effects in children with primary headache, with or without sleep disorders. Tryptophan may reduce night awakenings and improve the efficiency of sleep. Primary headache has been related to low amounts of magnesium in serum, and integration with magnesium appears to be effective in reducing headache attacks without adverse effects. There are different observational reports and uncontrolled studies suggesting a possible synergistic effect for these nutraceuticals, but there is now a need for high-quality randomized controlled trials in order to confirm these positive preliminary findings.

The efficacy of combined bright light and melatonin therapies on sleep and circadian outcomes: A systematic review

The aim of this systematic review was to investigate the effects of combined melatonin and bright light therapies on improved sleep and circadian outcomes. We conducted a systematic review that resulted in a total of eight papers meeting criteria. Four papers investigated the effectiveness of combined therapy in inducing a circadian phase shift on healthy participants. Combined therapy outperformed single light and melatonin therapies in phase advancing, but not in delaying, dim light melatonin onset (DLMO). The other four papers investigated the effect of combined therapy on sleep outcomes. Two of them were performed in elderly populations suffering from cognitive decline and two in delayed sleep-wake phase disorder (DSWPD) patients. While combined therapy was more beneficial than single therapy in elderly populations it did not show any benefit in DSWPD patients. The reported adverse effects of melatonin in elderly populations must be carefully considered. Future studies should investigate the separate and combined effect of melatonin and bright light on sleep and circadian outcomes in different target populations.

Melatonin (MEL) and its use in circadian rhythm sleep-wake disorders: Recommendations of the French Medical and Research Sleep Society (SFRMS)

The French society of medical research on sleep (SFRMS) appointed a group of experts to conduct a consensus conference in order to study the indications and prescription status of exogenous melatonin (MEL). Eleven sleep physicians/researchers investigated in subgroups the use of MEL in different domains of healthcare in line with their subspecialties (circadian sleep/wake rhythm disorders, psychiatric disorders, neurological disorders, pediatric and neurodevelopmental disorders). In this article we present a summary of the main conclusions of the expert group on MEL therapy in circadian sleep/wake rhythm disorders such us delayed sleep-wake disorder, non-24-hour sleep wake rhythm disorder and jet lag.

Association between circadian disruption and diseases: A narrative review

Circadian rhythms play an important role in a wide range of human physiology and pathology. Individuals increasingly experience situations such as night-shift work schedules, likely leading to circadian disruption. Recent studies have also demonstrated that patients with other diseases often show symptoms of circadian disruption as manifested by the sleep-wake cycle and other biological rhythms. Circadian disruption often results in changes to the phase, period, and amplitude of the sleep-wake cycle, melatonin rhythm, and core body temperature. Several cardiometabolic, psychiatric, and neurodegenerative diseases are closely related to circadian disruption. Several interventions are also available, including phototherapy, exogenous melatonin, and exercise. The cumulative findings suggest that circadian disruption can increase risk for some cardiometabolic diseases. Circadian disruption also acts as a concomitant symptom of several psychiatric and neurodegenerative diseases. More attention should be paid to evaluating the impact of circadian disruption on these related diseases, as well as the benefits of the mitigation interventions for both circadian disruption and related diseases.

Circadian disruption and human health: A bidirectional relationship

Circadian rhythm disorders have been classically associated with disorders of abnormal timing of the sleep-wake cycle, however circadian dysfunction can play a role in a wide range of pathology, ranging from the increased risk for cardiometabolic disease and malignancy in shift workers, prompting the need for a new field focused on the larger concept of circadian medicine. The relationship between circadian disruption and human health is bidirectional, with changes in circadian amplitude often preceding the classical symptoms of neurodegenerative disorders. As our understanding of the importance of circadian dysfunction in disease grows, we need to develop better clinical techniques for identifying circadian rhythms and also develop circadian based strategies for disease management. Overall this review highlights the need to bring the concept of time to all aspects of medicine, emphasizing circadian medicine as a prime example of both personalized and precision medicine.

Efficacy of melatonin with behavioural sleep-wake scheduling for delayed sleep-wake phase disorder: A double-blind, randomised clinical trial

BACKGROUND

Delayed Sleep-Wake Phase Disorder (DSWPD) is characterised by sleep initiation insomnia when attempting sleep at conventional times and difficulty waking at the required time for daytime commitments. Although there are published therapeutic guidelines for the administration of melatonin for DSWPD, to our knowledge, randomised controlled trials are lacking. This trial tested the efficacy of 0.5 mg melatonin, combined with behavioural sleep-wake scheduling, for improving sleep initiation in clinically diagnosed DSWPD patients with a delayed endogenous melatonin rhythm relative to patient-desired (or -required) bedtime (DBT).

METHODS

This randomised, placebo-controlled, double-blind clinical trial was conducted in an Australian outpatient DSWPD population. Following 1-wk baseline, clinically diagnosed DSWPD patients with delayed melatonin rhythm relative to DBT (salivary dim light melatonin onset [DLMO] after or within 30 min before DBT) were randomised to 4-wk treatment with 0.5 mg fast-release melatonin or placebo 1 h before DBT for at least 5 consecutive nights per week. All patients received behavioural sleep-wake scheduling, consisting of bedtime scheduled at DBT. The primary outcome was actigraphic sleep onset time. Secondary outcomes were sleep efficiency in the first third of time in bed (SE T1) on treatment nights, subjective sleep-related daytime impairment (Patient Reported Outcomes Measurement Information System [PROMIS]), PROMIS sleep disturbance, measures of daytime sleepiness, clinician-rated change in illness severity, and DLMO time.

FINDINGS

Between September 13, 2012 and September 1, 2014, 307 participants were registered; 116 were randomised to treatment (intention-to-treat n = 116; n = 62 males; mean age, 29.0 y). Relative to baseline and compared to placebo, sleep onset occurred 34 min earlier (95% confidence interval [CI] -60 to -8) in the melatonin group. SE T1 increased; PROMIS sleep-related impairment, PROMIS sleep disturbance, insomnia severity, and functional disability decreased; and a greater proportion of patients showed more than minimal clinician-rated improvement following melatonin treatment (52.8%) compared to placebo (24.0%) (P < 0.05). The groups did not differ in the number of nights treatment was taken per protocol. Post-treatment DLMO assessed in a subset of patients (n = 43) was not significantly different between groups. Adverse events included light-headedness, daytime sleepiness, and decreased libido, although rates were similar between treatment groups. The clinical benefits or safety of melatonin with long-term treatment were not assessed, and it remains unknown whether the same treatment regime would benefit patients experiencing DSWPD sleep symptomology without a delay in the endogenous melatonin rhythm.

CONCLUSIONS

In this study, melatonin treatment 1 h prior to DBT combined with behavioural sleep-wake scheduling was efficacious for improving objective and subjective measures of sleep disturbances and sleep-related impairments in DSWPD patients with delayed circadian phase relative to DBT. Improvements were achieved largely through the sleep-promoting effects of melatonin, combined with behavioural sleep-wake scheduling.

TRIAL REGISTRATION

This trial was registered with the Australian New Zealand Clinical Trials Registry, ACTRN12612000425897.

Delayed sleep phase syndrome and bipolar disorder: Pathogenesis and available common biomarkers

Circadian rhythm disturbances are common in bipolar affective disorder (BD). Delayed sleep-wake phase syndrome (DSWPD) is the most prevalent circadian rhythm sleep-wake disorder (CRSWDs) and is frequently observed in BD. It is unclear whether DSWPD in BD is an independent process or is a consequence of BD. In this hypothetical review, we discuss the overlap between BD and DSWPD and potential common biomarkers for DSWPD and BD. The review will include a discussion of the genetics of DSWPD and BD. Biomarkers elucidating the pathophysiological processes occurring in these two disorders may offer insight into the etiology and prognosis of both conditions.

Evidence for the efficacy of melatonin in the treatment of primary adult sleep disorders

Melatonin is a physiological hormone involved in sleep timing and is currently used exogenously in the treatment of primary and secondary sleep disorders with empirical evidence of efficacy, but very little evidence from randomised, controlled studies. The aim of this meta-analysis was to assess the evidence base for the therapeutic effects of exogenous melatonin in treating primary sleep disorders. An electronic literature review search of MEDLINE (1950-present) Embase (1980- present), PsycINFO (1987- present), and Scopus (1990- present), along with a hand-searching of key journals was performed in July 2013 and then again in May 2015. This identified all studies that compared the effect of exogenous melatonin and placebo in patients with primary insomnia, delayed sleep phase syndrome, non 24-h sleep wake syndrome in people who are blind, and rapid eye movement-behaviour disorder. Meta-analyses were performed to determine the magnitude of effect in studies of melatonin in improving sleep. A total of 5030 studies were identified; of these citations, 12 were included for review based on the inclusion criteria of being: double or single-blind, randomised and controlled. Results from the meta-analyses showed the most convincing evidence for exogenous melatonin use was in reducing sleep onset latency in primary insomnia (p = 0.002), delayed sleep phase syndrome (p < 0.0001), and regulating the sleep-wake patterns in blind patients compared with placebo. These findings highlight the potential importance of melatonin in treating certain first degree sleep disorders. The development of large-scale, randomised, controlled trials is recommended to provide further evidence for therapeutic use of melatonin in a variety of sleep difficulties.

Ramelteon (TAK-375) Accelerates Reentrainment of Circadian Rhythm after a Phase Advance of the Light-Dark Cycle in Rats

In vivo pharmacological effects of ramelteon (TAK-375), a novel, highly MT1/MT2-selective receptor agonist, were studied in rats to determine ramelteon’s ability to reentrain the circadian rhythm after an abrupt phase advance. Experiments were also conducted to assess the potential cognitive side effects of ramelteon and its potential to become a drug of abuse. After an abrupt 8-h phase shift, ramelteon (0.1 and 1 mg/kg, p.o.) and melatonin (10 mg/kg, p.o.) accelerated reentrainment of running wheel activity rhythm to the new lightdark cycle. Ramelteon (3-30 mg/kg, p.o.) and melatonin (10-100 mg/kg, p.o.) did not affect learning or memory in rats tested by the water maze task and the delayed match to position task, although diazepam and triazolam impaired both of the tasks. Neither ramelteon (3-30 mg/kg, p.o.) nor melatonin (10-100mg/kg, p.o.) demonstrated a rewarding property in the conditioned place-preference test, implying that MT1/MT2 receptor agonists have no abuse potential. In contrast, benzodiazepines and morphine showed rewarding properties in this test. The authors’ results suggest that ramelteon may be useful for treatment of circadian rhythm sleep disorders without adverse effects typically associated with benzodiazepine use, such as learning and memory impairment, and drug dependence.

Wearing blue light-blocking glasses in the evening advances circadian rhythms in the patients with delayed sleep phase disorder: An open-label trial

It has been recently discovered that blue wavelengths form the portion of the visible electromagnetic spectrum that most potently regulates circadian rhythm. We investigated the effect of blue light-blocking glasses in subjects with delayed sleep phase disorder (DSPD). This open-label trial was conducted over 4 consecutive weeks. The DSPD patients were instructed to wear blue light-blocking amber glasses from 21:00 p.m. to bedtime, every evening for 2 weeks. To ascertain the outcome of this intervention, we measured dim light melatonin onset (DLMO) and actigraphic sleep data at baseline and after the treatment. Nine consecutive DSPD patients participated in this study. Most subjects could complete the treatment with the exception of one patient who hoped for changing to drug therapy before the treatment was completed. The patients who used amber lens showed an advance of 78 min in DLMO value, although the change was not statistically significant (p = 0.145). Nevertheless, the sleep onset time measured by actigraph was advanced by 132 min after the treatment (p = 0.034). These data suggest that wearing amber lenses may be an effective and safe intervention for the patients with DSPD. These findings also warrant replication in a larger patient cohort with controlled observations.

Melatonin rhythms in renal transplant recipients with sleep-wake disturbances

We assessed salivary melatonin levels in renal transplant (RTx) recipients who participated in a randomised, multicentre wait-list controlled trial on the effect of bright light therapy on their sleep and circadian rhythms. A large proportion of RTx recipients in our cohort had unexpectedly low melatonin values, which precluded calculation of the dim-light melatonin onset (DLMO) as a circadian marker. Thus, the aim of this post hoc analysis was to describe the melatonin profile of home-dwelling RTx recipients diagnosed with sleep-wake disturbances (SWDs). The participants were characterised by means of sleep questionnaires, validated psychometric instruments [Pittsburgh sleep quality Index (PSQI), Epworth sleepiness scale (ESS), Morningness-Eveningness Questionnaire (MEQ) and Depression, Anxiety and Stress Scale (DASS)] in addition to melatonin assay in saliva. Data were analysed with descriptive statistics and group comparisons made with appropriate post hoc tests. RTx recipients [n = 29 (aged 54.83 ± 13.73, transplanted 10.62 ± 6.84 years ago)] were retrospectively grouped into two groups: RTx recipients whose dim light melatonin onset (DLMO) could be calculated (n = 11) and those whose DLMO could not be calculated (n = 18). RTx recipients having a measurable DLMO had a number of differences from those without DLMO: they were younger [46.4 ± 14.9 compared to 60.0 ± 10.3 (p = .007)], had higher haemoglobin values [135.36 ± 12.01 versus 122.82 ± 11.56 (p = .01)], less anxiety [4 (0;8) versus 12 (6.5;14) (p = .021)] and a better overall sense of coherence [SOC Score: 71.09 ± 12.78 versus 56.28 ± 15.48 (p = 0.013)]. These results suggest that RTx recipients whose DLMO could be calculated have less health impairments, underlying the relevance of a stable circadian system.

Circadian Rhythm Sleep-Wake Disorders

The circadian system regulates the timing and expression of nearly all biological processes, most notably, the sleep-wake cycle, and disruption of this system can result in adverse effects on both physical and mental health. The circadian rhythm sleep-wake disorders (CRSWDs) consist of 5 disorders that are due primarily to pathology of the circadian clock or to a misalignment of the timing of the endogenous circadian rhythm with the environment. This article outlines the nature of these disorders, the association of many of these disorders with psychiatric illness, and available treatment options.

60 YEARS OF NEUROENDOCRINOLOGY: Regulation of mammalian neuroendocrine physiology and rhythms by melatonin

The isolation of melatonin was first reported in 1958. Since the demonstration that pineal melatonin synthesis reflects both daily and seasonal time, melatonin has become a key element of chronobiology research. In mammals, pineal melatonin is essential for transducing day-length information into seasonal physiological responses. Due to its lipophilic nature, melatonin is able to cross the placenta and is believed to regulate multiple aspects of perinatal physiology. The endogenous daily melatonin rhythm is also likely to play a role in the maintenance of synchrony between circadian clocks throughout the adult body. Pharmacological doses of melatonin are effective in resetting circadian rhythms if taken at an appropriate time of day, and can acutely regulate factors such as body temperature and alertness, especially when taken during the day. Despite the extensive literature on melatonin physiology, some key questions remain unanswered. In particular, the amplitude of melatonin rhythms has been recently associated with diseases such as type 2 diabetes mellitus but understanding of the physiological significance of melatonin rhythm amplitude remains poorly understood.

Telling biological time from a blood sample: current capabilities and future potential

Circadian rhythms, near-24 h oscillations that reflect homeostatic control by an internal timing system rather than the influence of external factors, are an important and sometimes underappreciated aspect of human physiology and biochemistry. Over the past few decades, the pineal gland hormone melatonin has been established both as a robust marker of circadian phase in plasma or saliva and as a chronobiotic drug administered to reset the timing of the circadian oscillator. Recent work by our own and other laboratories has sought to systematically investigate whole categories of molecular components in blood samples in a hypothesis-free fashion by employing metabolomic methodologies to study low molecular weight compounds and transcriptomic methodologies to study gene expression in white blood cells, respectively. A number of components have been pinpointed that show a rhythmic circadian variation or are affected by imposed factors such as sleep deprivation. Although melatonin, a robust and reliable circadian phase marker, will be a hard act to follow, these lines of research suggest numerous potential leads for useful new markers of biological timing.

Current role of melatonin in pediatric neurology: clinical recommendations

BACKGROUND/PURPOSE

Melatonin, an indoleamine secreted by the pineal gland, plays a key role in regulating circadian rhythm. It has chronobiotic, antioxidant, anti-inflammatory and free radical scavenging properties.

METHODS

A conference in Rome in 2014 aimed to establish consensus on the roles of melatonin in children and on treatment guidelines.

RESULTS AND CONCLUSION

The best evidence for efficacy is in sleep onset insomnia and delayed sleep phase syndrome. It is most effective when administered 3-5 h before physiological dim light melatonin onset. There is no evidence that extended-release melatonin confers advantage over immediate release. Many children with developmental disorders, such as autism spectrum disorder, attention-deficit/hyperactivity disorder and intellectual disability have sleep disturbance and can benefit from melatonin treatment. Melatonin decreases sleep onset latency and increases total sleep time but does not decrease night awakenings. Decreased CYP 1A2 activity, genetically determined or from concomitant medication, can slow metabolism, with loss of variation in melatonin level and loss of effect. Decreasing the dose can remedy this. Animal work and limited human data suggest that melatonin does not exacerbate seizures and might decrease them. Melatonin has been used successfully in treating headache. Animal work has confirmed a neuroprotective effect of melatonin, suggesting a role in minimising neuronal damage from birth asphyxia; results from human studies are awaited. Melatonin can also be of value in the performance of sleep EEGs and as sedation for brainstem auditory evoked potential assessments. No serious adverse effects of melatonin in humans have been identified.

Long-term effects of melatonin on quality of life and sleep in haemodialysis patients (Melody study): a randomized controlled trial

AIM

The disturbed circadian rhythm in haemodialysis patients results in perturbed sleep. Short term melatonin supplementation has alleviated these sleep problems. Our aim was to investigate the effects of long-term melatonin supplementation on quality of life and sleep.

METHODS

In this randomized double-blind placebo-controlled trial haemodialysis patients suffering from subjective sleep problems received melatonin 3 mg day(-1) vs. placebo during 12 months. The primary endpoint quality of life parameter 'vitality' was measured with Medical Outcomes Study Short Form-36. Secondary outcomes were improvement of three sleep parameters measured by actigraphy and nighttime salivary melatonin concentrations.

RESULTS

Sixty-seven patients were randomized. Forty-two patients completed the trial. With melatonin, no beneficial effect on vitality was seen. Other quality of life parameters showed both advantageous and disadvantageous effects of melatonin. Considering sleep, at 3 months sleep efficiency and actual sleep time had improved with melatonin compared with placebo on haemodialysis days (difference 7.6%, 95% CI 0.77, 14.4 and 49 min, 95% CI 2.1, 95.9, respectively). At 12 months none of the sleep parameters differed significantly from placebo. Melatonin salivary concentrations at 6 months had significantly increased in the melatonin group compared with the placebo group.

CONCLUSIONS

The high drop-out rate limits the strength of our conclusions. However, although a previous study reported beneficial short term effects of melatonin on sleep in haemodialysis patients, in this long-term study the positive effects disappeared during follow up (6-12 months). Also the quality of life parameter, vitality, did not improve. Efforts should be made to elucidate the mechanism responsible for the loss of effect with chronic use.

Why the dim light melatonin onset (DLMO) should be measured before treatment of patients with circadian rhythm sleep disorders

Treatment of circadian rhythm sleep disorders (CRSD) may include light therapy, chronotherapy and melatonin. Exogenous melatonin is increasingly being used in patients with insomnia or CRSD. Although pharmacopoeias and the European food safety authority (EFSA) recommend administering melatonin 1-2 h before desired bedtime, several studies have shown that melatonin is not always effective if administered according to that recommendation. Crucial for optimal treatment of CRSD, melatonin and other treatments should be administered at a time related to individual circadian timing (typically assessed using the dim light melatonin onset (DLMO)). If not administered according to the individual patient's circadian timing, melatonin and other treatments may not only be ineffective, they may even result in contrary effects. Endogenous melatonin levels can be measured reliably in saliva collected at the patient's home. A clinically reliably DLMO can be calculated using a fixed threshold. Diary and polysomnographic sleep-onset time do not reliably predict DLMO or circadian timing in patients with CRSD. Knowing the patient's individual circadian timing by assessing DLMO can improve diagnosis and treatment of CRSD with melatonin as well as other therapies such as light or chronotherapy, and optimizing treatment timing will shorten the time required to achieve results.

A randomized controlled trial with bright light and melatonin for the treatment of delayed sleep phase disorder: effects on subjective and objective sleepiness and cognitive function

Delayed sleep phase disorder (DSPD) is a circadian rhythm sleep disorder. Patients with DSPD have problems initiating sleep if they go to bed at a conventional time, and they often have problems waking at desired times. If they rise early in the morning, they usually experience severe sleepiness during morning hours. In the present study, we investigated the short- and long-term effects on measures of subjective and objective sleepiness and cognitive function of bright light and melatonin treatment alongside gradually advanced rise times in adolescents and young adults. Four treatment conditions were used in the short-term intervention (2 weeks): dim light (placebo) + placebo capsule, bright light + placebo capsule, dim light (placebo) + melatonin capsule, and bright light + melatonin capsule. This was followed by a long-term intervention (3 months) including 2 conditions: no treatment and combined bright light + melatonin treatment. Effects of treatment on sleepiness and fatigue were the primary outcome measures, and effects on cognitive function were secondary outcome measures. On a gradual advancement of the rise time schedule, all treatment conditions (bright light, melatonin, combination, and placebo) were almost equally effective in improving subjective daytime sleepiness, fatigue, and cognitive function in the 2-week study. The 2-week intervention showed no effect on objective sleepiness. Long-term treatment increased some of the positive effects seen after 2 weeks. The combined bright light and melatonin treatment improved subjective daytime sleepiness, fatigue, and cognitive function in the 3-month study. The no-treatment group returned to baseline values on most variables. In conclusion, a gradual advancement of rise times seems to produce positive effects on subjective sleepiness, fatigue, and cognitive performance during short-term treatment of patients with DSPD. However, the benefits from gradually advanced rise times seem to wear off, suggesting that the continuation of bright light and melatonin treatment is beneficial to maintain positive effects over time.

A randomized controlled trial with bright light and melatonin for delayed sleep phase disorder: effects on subjective and objective sleep

Delayed sleep phase disorder (DSPD) is assumed to be common amongst adolescents, with potentially severe consequences in terms of school attendance and daytime functioning. The most common treatment approaches for DSPD are based on the administration of bright light and/or exogenous melatonin with or without adjunct behavioural instructions. Much is generally known about the chronobiological effects of light and melatonin. However, placebo-controlled treatment studies for DSPD are scarce, in particular in adolescents and young adults, and no standardized guidelines exist regarding treatment. The aim of the present study was, therefore, to investigate the short- and long-term effects on sleep of a DSPD treatment protocol involving administration of timed bright light and melatonin alongside gradual advancement of rise time in adolescents and young adults with DSPD in a randomized controlled trial and an open label follow-up study. A total of 40 adolescents and young adults (age range 16-25 years) diagnosed with DSPD were recruited to participate in the study. The participants were randomized to receive treatment for two weeks in one of four treatment conditions: dim light and placebo capsules, bright light and placebo capsules, dim light and melatonin capsules or bright light and melatonin capsules. In a follow-up study, participants were re-randomized to either receive treatment with the combination of bright light and melatonin or no treatment in an open label trial for approximately three months. Light and capsules were administered alongside gradual advancement of rise times. The main end points were sleep as assessed by sleep diaries and actigraphy recordings and circadian phase as assessed by salivary dim light melatonin onset (DLMO). During the two-week intervention, the timing of sleep and DLMO was advanced in all treatment conditions as seen by about 1 h advance of bed time, 2 h advance of rise time and 2 h advance of DLMO in all four groups. Sleep duration was reduced with approximately 1 h. At three-month follow-up, only the treatment group had maintained an advanced sleep phase. Sleep duration had returned to baseline levels in both groups. In conclusion, gradual advancement of rise time produced a phase advance during the two-week intervention, irrespective of treatment condition. Termination of treatment caused relapse into delayed sleep times, whereas long-term treatment with bright light and melatonin (three months) allowed maintenance of the advanced sleep phase.

Meta-analysis: melatonin for the treatment of primary sleep disorders

STUDY OBJECTIVES

To investigate the efficacy of melatonin compared to placebo in improving sleep parameters in patients with primary sleep disorders.

DESIGN

PubMed was searched for randomized, placebo-controlled trials examining the effects of melatonin for the treatment of primary sleep disorders. Primary outcomes examined were improvement in sleep latency, sleep quality and total sleep time. Meta-regression was performed to examine the influence of dose and duration of melatonin on reported efficacy.

PARTICIPANTS

Adults and children diagnosed with primary sleep disorders.

INTERVENTIONS

Melatonin compared to placebo.

RESULTS

Nineteen studies involving 1683 subjects were included in this meta-analysis. Melatonin demonstrated significant efficacy in reducing sleep latency (weighted mean difference (WMD) = 7.06 minutes [95% CI 4.37 to 9.75], Z = 5.15, p<0.001) and increasing total sleep time (WMD = 8.25 minutes [95% CI 1.74 to 14.75], Z = 2.48, p = 0.013). Trials with longer duration and using higher doses of melatonin demonstrated greater effects on decreasing sleep latency and increasing total sleep time. Overall sleep quality was significantly improved in subjects taking melatonin (standardized mean difference = 0.22 [95% CI: 0.12 to 0.32], Z = 4.52, p<0.001) compared to placebo. No significant effects of trial duration and melatonin dose were observed on sleep quality.

CONCLUSION

This meta-analysis demonstrates that melatonin decreases sleep onset latency, increases total sleep time and improves overall sleep quality. The effects of melatonin on sleep are modest but do not appear to dissipate with continued melatonin use. Although the absolute benefit of melatonin compared to placebo is smaller than other pharmacological treatments for insomnia, melatonin may have a role in the treatment of insomnia given its relatively benign side-effect profile compared to these agents.

Circadian rhythm sleep disorders

There have been remarkable advances in our understanding of the molecular, cellular, and physiologic mechanisms underlying the regulation of circadian rhythms, and of the impact of circadian dysfunction on health and disease. This information has transformed our understanding of the effect of circadian rhythm sleep disorders (CRSD) on health, performance, and safety. CRSDs are caused by alterations of the central circadian timekeeping system, or a misalignment of the endogenous circadian rhythm and the external environment. This article reviews circadian biology and discusses the pathophysiology, clinical features, diagnosis, and treatment of the most commonly encountered CRSDs in clinical practice.

Manipulating the sleep-wake cycle and circadian rhythms to improve clinical management of major depression

BACKGROUND

Clinical psychiatry has always been limited by the lack of objective tests to substantiate diagnoses and a lack of specific treatments that target underlying pathophysiology. One area in which these twin failures has been most frustrating is major depression. Due to very considerable progress in the basic and clinical neurosciences of sleep-wake cycles and underlying circadian systems this situation is now rapidly changing.

DISCUSSION

The development of specific behavioral or pharmacological strategies that target these basic regulatory systems is driving renewed clinical interest. Here, we explore the extent to which objective tests of sleep-wake cycles and circadian function - namely, those that measure timing or synchrony of circadian-dependent physiology as well as daytime activity and nighttime sleep patterns - can be used to identify a sub-class of patients with major depression who have disturbed circadian profiles.

SUMMARY

Once this unique pathophysiology is characterized, a highly personalized treatment plan can be proposed and monitored. New treatments will now be designed and old treatments re-evaluated on the basis of their effects on objective measures of sleep-wake cycles, circadian rhythms and related metabolic systems.

Melatonin in the afternoons of a gradually advancing sleep schedule enhances the circadian rhythm phase advance

RATIONALE

We test methods to advance (shift earlier) circadian rhythms without producing misalignment between rhythms and sleep. We previously tested (1) a gradually advancing sleep/dark schedule plus morning bright light and afternoon/evening melatonin and (2) the same sleep schedule with only morning bright light. Now we report on the same sleep schedule with only afternoon/evening melatonin.

OBJECTIVES

This study aims to examine phase advances, sleepiness, and performance in response to melatonin compared to placebo.

METHODS

Twelve adults (five female individuals) aged 20-45 years (mean ± SD = 28.3 ± 7.3 years) completed this within-subjects placebo-controlled counterbalanced study. The participants slept on fixed 8-h sleep schedules for nine days. Then, sleep/dark was advanced by 1 h/day for three consecutive days of treatment. The participants took 3 mg of melatonin or placebo 11 h before baseline sleep midpoint (the optimal time to produce phase advances) on the first treatment day and 1 h earlier on each subsequent day. We measured the dim light melatonin onset before and after treatment. The participants rated subjective symptoms throughout the study. They completed the Psychomotor Vigilance Task and rated sleepiness from 1 h before pill ingestion until bedtime on each treatment day.

RESULTS

Melatonin produced significantly larger advances (1.3 ± 0.7 h) compared to placebo (0.7 ± 0.7 h); however, in the hours between melatonin ingestion and bed, melatonin caused sleepiness and performance decrements.

CONCLUSIONS

Adding afternoon/evening melatonin to the gradually advancing sleep schedule increased the phase advance, but given the side effects, like sleepiness, it is better to use morning bright light and perhaps a lower dose of melatonin.

Melatonin treatment effects on adolescent students' sleep timing and sleepiness in a placebo-controlled crossover study

During the last few decades, the incidence of sleep-onset insomnia, due to delay of circadian phase, has increased substantially among adolescents all over the world. We wanted to investigate whether a small dose of melatonin given daily, administered in the afternoon, could advance the sleep timing in teenagers. Twenty-one students, aged 14-19 yrs, with sleep-onset difficulties during school weeks were recruited. The study was a randomized, double blind, placebo (PL)-controlled crossover trial, lasting 5 wks. During the first 6 d in wks 2 and 4, the students received either PL or melatonin (1 mg) capsules between 16:30 and 18:00 h. During the first 6 d of wk 5, all students received melatonin. Wks 1 and 3 were capsule-free. In the last evening of each week and the following morning, the students produced saliva samples at home for later melatonin analysis. The samples were produced the same time each week, as late as possible in the evening and as early as possible in the morning. Both the student and one parent received automatic mobile text messages 15 min before saliva sampling times and capsule intake at agreed times. Diaries with registration of presumed sleep, subjective sleepiness during the day (Karolinska Sleepiness Scale, KSS) and times for capsule intake and saliva samplings were completed each day. Primary analysis over 5 wks gave significant results for melatonin, sleep and KSS. Post hoc analysis showed that reported sleep-onset times were advanced after melatonin school weeks compared with PL school weeks (p < .005) and that sleep length was longer (p < .05). After the last melatonin school week, the students fell asleep 68 min earlier and slept 62 min longer each night compared with the baseline week. Morning melatonin values in saliva diminished compared with PL (p < .001) and evening values increased (p < .001), indicating a possible sleep phase advance. Compared with PL school weeks, the students reported less wake up (p < .05), less school daytime sleepiness (p < .05) and increased evening sleepiness (p < .005) during melatonin weeks. We conclude that a small dose of melatonin given daily, administered in the afternoon, could advance the sleep timing and make the students more alert during school days even if they continued their often irregular sleep habits during weekends.

The role of melatonin in patients with chronic kidney disease undergoing haemodialysis

Patients with chronic kidney disease including those undergoing haemodialysis have deranged sleep-wake pattern. In large part this is due to an abnormal circadian cycle of melatonin, a hormone secreted by the pineal gland in the evening and induces sleep. Subjects undergoing automated peritoneal dialysis or nocturnal haemodialysis have better sleep profile compared to those on daytime dialysis. Studies have shown that exogenous melatonin improves sleep-wake cycle in daytime haemodialysis patients. However, large randomised controlled trials are needed in order to establish its role in this patient population.

Wrist actigraphy

To record sleep, actigraph devices are worn on the wrist and record movements that can be used to estimate sleep parameters with specialized algorithms in computer software programs. With the recent establishment of a Current Procedural Terminology code for wrist actigraphy, this technology is being used increasingly in clinical settings as actigraphy has the advantage of providing objective information on sleep habits in the patient's natural sleep environment. Actigraphy has been well validated for the estimation of nighttime sleep parameters across age groups, but the validity of the estimation of sleep-onset latency and daytime sleeping is limited. Clinical guidelines and research suggest that wrist actigraphy is particularly useful in the documentation of sleep patterns prior to a multiple sleep latency test, in the evaluation of circadian rhythm sleep disorders, to evaluate treatment outcomes, and as an adjunct to home monitoring of sleep-disordered breathing. Actigraphy has also been well studied in the evaluation of sleep in the context of depression and dementia. Although actigraphy should not be viewed as a substitute for clinical interviews, sleep diaries, or overnight polysomnography when indicated, it can provide useful information about sleep in the natural sleep environment and/or when extended monitoring is clinically indicated.

Circadian rhythm sleep disorders

This article begins with a review of the major central nervous system functional systems that allow for optimal alertness during the waking day, and the rapid initiation and good maintenance of sleep at night. Subsequent sections discuss each of the 6 primary circadian rhythm sleep disorders. Attention is paid to known or suspected pathophysiology, diagnostic criteria and assessment methodology, and treatment options. The article concludes with a discussion of challenges that must be met to improve the recognition and treatment of these quite impactful sleep disorders.

The use of exogenous melatonin in delayed sleep phase disorder: a meta-analysis

STUDY OBJECTIVES

To perform a meta-analysis of the efficacy and safety of exogenous melatonin in advancing sleep-wake rhythm in patients with delayed sleep phase disorder.

DESIGN

Meta analysis of papers indexed for PubMed, Embase, and the abstracts of sleep and chronobiologic societies (1990-2009).

PATIENTS

Individuals with delayed sleep phase disorder.

INTERVENTIONS

Administration of melatonin.

MEASUREMENTS AND RESULTS

A meta-analysis of data of randomized controlled trials involving individuals with delayed sleep phase disorder that were published in English, compared melatonin with placebo, and reported 1 or more of the following: endogenous melatonin onset, clock hour of sleep onset, wake-up time, sleep-onset latency, and total sleep time. The 5 trials including 91 adults and 4 trials including 226 children showed that melatonin treatment advanced mean endogenous melatonin onset by 1.18 hours (95% confidence interval [CI]: 0.89-1.48 h) and clock hour of sleep onset by 0.67 hours (95% CI: 0.45-0.89 h). Melatonin decreased sleep-onset latency by 23.27 minutes (95% CI: 4.83 -41.72 min). The wake-up time and total sleep time did not change significantly.

CONCLUSIONS

Melatonin is effective in advancing sleep-wake rhythm and endogenous melatonin rhythm in delayed sleep phase disorder.

Therapeutics for Circadian Rhythm Sleep Disorders

The sleep-wake cycle is regulated by the interaction of endogenous circadian and homeostatic processes. The circadian system provides timing information for most physiological rhythms, including the sleep and wake cycle. In addition, the central circadian clock located in the suprachiasmatic nucleus of the hypothalamus has been shown to promote alertness during the day. Circadian rhythm sleep disorders arise when there is a misalignment between the timing of the endogenous circadian rhythms and the external environment or when there is dysfunction of the circadian clock or its entrainment pathways. The primary synchronizing agents of the circadian system are light and melatonin. Light is the strongest entraining agent of circadian rhythms and timed exposure to bright light is often used in the treatment of circadian rhythm sleep disorders. In addition, timed administration of melatonin, either alone or in combination with light therapy has been shown to be useful in the treatment of the following circadian rhythm sleep disorders: delayed sleep phase, advanced sleep phase, free-running, irregular sleep wake, jet lag and shift work.

Chronobiology and insomnia: pathophysiology and treatment of circadian rhythm sleep disorders

This review summarizes current knowledge of sleep disorders with a chronobiological basis, including: delayed sleep phase syndrome, advanced sleep phase syndrome, non24 h sleep-wake syndrome and irregular sleep-wake pattern disorder. These circadian rhythm sleep disorders are characterized by a misalignment between the timing of the sleep period with respect to the day-night cycle and as a consequence of patients attempting to maintain 'normal' social hours, reduced sleep quality. In addition to the specific circadian rhythm sleep disorders, this review will also examine current drug (e.g., hypnotics and melatonin) and nondrug (e.g., bright light therapy and chronotherapy) treatments, the overlap with psychophysiological insomnia and future directions.

Melatonin decreases daytime challenging behaviour in persons with intellectual disability and chronic insomnia

BACKGROUND

Persons with intellectual disability (ID) and sleep problems exhibit more daytime challenging behaviours than persons with ID without sleep problems. Several anecdotal reports suggest that melatonin is not only effective in the treatment of insomnia, but also decreases daytime challenging behaviour. However, the effect of melatonin treatment on daytime challenging behaviour in persons with ID has not been investigated in a randomised controlled trial.

METHOD

We investigated the effects of melatonin on challenging behaviour using data from two randomised controlled trials on the efficacy of melatonin on sleep problems in 49 persons (25 men, 24 women; mean age 18.2 years, SD = 17.1) with ID and chronic insomnia. Participants received either melatonin 5 mg (<6 years 2.5 mg) or placebo during 4 weeks. Daytime challenging behaviour was measured by the Storend Gedragsschaal voor Zwakzinnigen - Maladaptive Behaviour Scale for the Mentally Retarded (SGZ; Kraijer & Kema, 1994) at baseline week and the end of the fourth treatment week. Salivary dim light melatonin onset (DLMO) was measured at baseline and the last day of the fourth treatment week. Sleep logs were used to gather information on sleep parameters.

RESULTS

Melatonin treatment significantly reduced SGZ scores, sleep latency, and number and duration of night wakes, and treatment increased total sleep time and advanced DLMO. However, after 4 weeks of treatment, change in SGZ scores did not significantly correlate with change in sleep parameters, nor with change in DLMO. Relatively strong correlations were found between change in SGZ scores, change in DLMO and number of night wakes.

CONCLUSIONS

Melatonin treatment in persons with ID and chronic insomnia decreases daytime challenging behaviour, probably by improving sleep maintenance or by improving circadian melatonin rhythmicity.

What keeps us awake? The role of clocks and hourglasses, light, and melatonin

What is it that keeps us awake? Our assumption is that we consciously control our daily activities including sleep-wake behavior, as indicated by our need to make use of an alarm clock to wake up in the morning in order to be at work on time. However, when we travel across multiple time zones or do shift work, we realize that our intentionally planned timings to rest and to remain active can interfere with an intrinsic regulation of sleep/wake cycles. This regulation is driven by a small region in the anterior hypothalamus of the brain, termed as the "circadian clock". This clock spontaneously synchronizes with the environmental light-dark cycle, thus enabling all organisms to adapt to and anticipate environmental changes. As a result, the circadian clock actively gates sleep and wakefulness to occur in synchrony with the light-dark cycles. Indeed, our internal clock is our best morning alarm clock, since it shuts off melatonin production and boosts cortisol secretion and heart rate 2-3h prior awakening from Morpheus arms. The main reason most of us still use artificial alarm clocks is that we habitually carry on a sleep depth and/or the sleep-wake timing is not ideally matched with our social/work schedule. This in turn can lead hourglass processes, as indexed by accumulated homeostatic sleep need over time, to strongly oppose the clock. To add to the complexity of our sleep and wakefulness behavior, light levels as well as exogenous melatonin can impinge on the clock, by means of their so-called zeitgeber (synchronizer) role or by acutely promoting sleep or wakefulness. Here we attempt to bring a holistic view on how light, melatonin, and the brain circuitry underlying circadian and homeostatic processes can modulate sleep and in particular alertness, by actively promoting awakening/arousal and sleep at certain times during the 24-h day.