Improved Sleep Efficiency Research Articles

Sleep in patients with large pleural effusion: impact of thoracentesis

This study aimed to evaluate the sleep quality and impact of thoracentesis on sleep in patients with a large pleural effusion. Patients with large unilateral pleural effusion were evaluated by the Pittsburgh Sleep Quality Index (PSQI) questionnaire and dyspnea Borg scale. Full polysomnography (PSG) was performed on the night before and 36h after thoracentesis. We studied 19 patients, 11 males and 8 females, age 55 ± 18years and body mass index of 26 ± 5kg/m(2). The baseline sleep quality was poor (PSQI = 9.1 ± 3.5). Thoracentesis removed 1.624 ± 796mL of pleural fluid and resulted in a significant decrease in dyspnea Borg scale (2.3 ± 2.1 vs. 0.8 ± 0.9, p < 0.001). The PSG before and after thoracentesis showed no significant change in apnea-hypopnea index and sleep time with oxygen saturation <90%. There was a significant improvement in sleep efficiency (76% vs. 81%, p = 0.006), decrease percent sleep stage 1 (16% vs. 14%, p = 0.002), and a trend improvement in total sleep time (344 ± 92 vs. 380 ± 69min, p = 0.056) and percentage of rapid eye movement sleep (15% vs. 20%, p = 0.053). No significant changes occurred in six patients that performed two consecutive PSG before thoracentesis. The improvement in sleep quality was not associated with the volume of pleural fluid withdrawn or changes in dyspnea. Patients with large pleural effusion have poor subjective and objective sleep quality that improves after thoracentesis.

Wake up to insomnia: future approaches to the management of insomnia

Wake up to insomnia: future approaches to the management of insomnia

Clinical Relevance of Disturbances of Sleep and Vigilance in Major Depressive Disorder

The primary objective of this article is to provide a concise review of the clinical relevance of sleep and vigilance in major depressive disorder. PubMed was reviewed (1990-2009) and English-language articles were identified using the key words sleep and depression and sleep and antidepressants. Secondary searches included articles cited in sources identified by the primary search. The narrative review provides brief descriptions of the normal physiology of sleep and changes associated with depression, as well as the impact of various treatments on these processes. Although it has long been known that sleep disturbances are an important characteristic of depression, relatively few studies have been conducted with the newer-generation antidepressants. Neither of the most widely used classes of antidepressants, the selective serotonin reuptake inhibitors and the serotonin-norepinephrine reuptake inhibitors, have particularly beneficial effects on sleep and, among the medications that reliably improve sleep efficiency, including mirtazapine and the tricyclic antidepressants, problems with daytime sedation can offset therapeutic benefit. Despite relatively widespread use, trazodone has not been demonstrated to be an effective and safe hypnotic in patients taking other antidepressants. For many patients, ongoing concomitant treatment with benzodiazepines and related drugs is the preferred option, again without convincing empirical support of longer-term efficacy. Among newer and investigational antidepressants, agomelatine shows promise with respect to both overall safety and effects on insomnia, although possible negative effects on liver function warrant further study. Sleep disturbances are a significant aspect of depressive syndromes, and relief of insomnia remains an important unmet need in antidepressant therapeutics. Development of a well-tolerated antidepressant medication that rapidly improves sleep maintenance without daytime sedation is a priority for drug development.

Mind-body interventions for the treatment of insomnia: a review

As insomnia is highly prevalent, and side effects of medication are well-known, mind-body interventions are increasingly being sought. The objective of this study is to present a narrative review regarding the effects of mind-body interventions for the treatment of insomnia. A PubMed search was conducted including only randomized, controlled trials in which the main objective was to treat insomnia. Twelve studies were selected. In three of the studies, objective parameters (polysomnography) were analyzed. Mind-body interventions were able to improve sleep efficiency and total sleep time. Most can ameliorate sleep quality; some can reduce the use of hypnotic drugs in those who are dependent on these drugs. According to the studies we selected, self-reported sleep was improved by all mind-body treatments, among them yoga, relaxation, Tai Chi Chih and music. Cognitive behavioral therapy seems to be the most effective mind-body intervention. Cognitive behavioral therapy was the only intervention that showed better results than medication. However, considering that only five of the twelve studies chosen reached a score of 3 in the Jadad scale, new studies with a higher methodological quality have to be conducted especially in mind-body interventions that belong to the complementary or alternative medicine field.

Remission of severe restless legs syndrome and periodic limb movements in sleep after bilateral excision of multiple foot neuromas: a case report

IntroductionRestless legs syndrome is a sensorimotor neurological disorder characterized by an urge to move the legs in response to uncomfortable leg sensations. While asleep, 70 to 90 percent of patients with restless legs syndrome have periodic limb movements in sleep. Frequent periodic limb movements in sleep and related brain arousals as documented by polysomnography are associated with poorer quality of sleep and daytime fatigue. Restless legs syndrome in middle age is sometimes associated with neuropathic foot dysesthesias. The causes of restless legs syndrome and periodic limb movements in sleep are unknown, but the sensorimotor symptoms are hypothesized to originate in the central nervous system. We have previously determined that bilateral forefoot digital nerve impingement masses (neuromas) may be a cause of both neuropathic foot dysesthesias and the leg restlessness of restless legs syndrome. To the best of our knowledge, this case is the first report of bilateral foot neuromas as a cause of periodic limb movements in sleep.Case presentationA 42-year-old Caucasian woman with severe restless legs syndrome and periodic limb movements in sleep and bilateral neuropathic foot dysesthesias was diagnosed as having neuromas in the second, third, and fourth metatarsal head interspaces of both feet. The third interspace neuromas represented regrowth (or 'stump') neuromas that had developed since bilateral third interspace neuroma excision five years earlier. Because intensive conservative treatments including repeated neuroma injections and various restless legs syndrome medications had failed, radical surgery was recommended. All six neuromas were excised. Leg restlessness, foot dysesthesias and subjective sleep quality improved immediately. Assessment after 18 days showed an 84 to 100 percent reduction of visual analog scale scores for specific dysesthesias and marked reductions of pre-operative scores of the Pittsburgh sleep quality index, fatigue severity scale, and the international restless legs syndrome rating scale (36 to 4). Polysomnography six weeks post-operatively showed improved sleep efficiency, a marked increase in rapid eye movement sleep, and marked reductions in hourly rates of both periodic limb movements in sleep with arousal (135.3 to 3.3) and spontaneous arousals (17.3 to 0).ConclusionThe immediate and near complete remission of symptoms, the histopathology of the excised tissues, and the marked improvement in polysomnographic parameters documented six weeks after surgery together indicate that this patient's severe restless legs syndrome and periodic limb movements in sleep was of peripheral nerve (foot neuroma) origin. Further study of foot neuromas as a source of periodic limb movements in sleep and as a cause of sleep dysfunction in patients with or without concomitant restless legs syndrome, is warranted.

Napping, Nighttime Sleep, and Cardiovascular Risk Factors in Mid-Life Adults

To evaluate the relations between sleep characteristics and cardiovascular risk factors and napping behavior, and to assess whether daytime napping leads to subsequent better or worse sleep. The sample consisted of 224 (African American, Caucasian, and Asian) middle-aged men and women. Sleep measures included nine nights of actigraphy and sleep diaries, sleep questionnaires, and one night of polysomnography to measure sleep disordered breathing. More frequent napping was associated with shorter nighttime sleep duration averaged across the nine nights of actigraphy (especially among African Americans), more daytime sleepiness, more pain and fatigue by diary, and increased body mass index and waist circumference. Shorter nighttime sleep duration was associated with taking a nap during the next day and taking a nap was associated with less efficient sleep the next night. Napping in middle-aged men and women is associated with overall less nighttime sleep in African Americans and lower sleep efficiency as measured by actigraphy, and increased BMI and central adiposity. These findings point to the importance of measuring of napping in understanding associations of sleep with cardiovascular risk.

Impact of the novel antidepressant agomelatine on disturbed sleep–wake cycles in depressed patients

Disturbance of sleep-wake cycles is common in major depressive disorder (MDD), usually as insomnia, but also as hypersomnia or reduced daytime alertness. Agomelatine, an MT(1) and MT(2) receptor agonist and 5-HT(2C) receptor antagonist, represents a novel approach in MDD, with proven antidepressant efficacy and a positive impact on the sleep-wake cycle. We review the effects of agomelatine 25/50 mg/day on objective and subjective measures of the sleep-wake cycle in MDD. Agomelatine improved all aspects of the sleep-wake cycle from as early as 1 week in randomized trials versus selective serotonin reuptake inhibitors and venlafaxine, particularly getting off to sleep and quality of sleep, with an improvement in daytime alertness. Agomelatine's effect on sleep architecture in MDD has been measured by polysomnography (PSG). There were significant improvements in sleep efficiency, slow-wave sleep (SWS), and the distribution of delta activity throughout the night, but no change in amount or latency of rapid eye movement (REM) sleep. Furthermore, the slow-wave sleep was resynchronized to the first sleep cycle of the night. Agomelatine, a novel antidepressant, improves disturbed sleep-wake cycles in MDD. The improvement of both nighttime sleep and daytime functioning with agomelatine are promising features of this antidepressant regarding the management of MDD.

Effects of Mindful Yoga on Sleep in Pregnant Women: A Pilot Study

The purpose of this experimental pilot study was to measure the effects of a mindfulness-based yoga intervention on sleep in pregnant women. Fifteen healthy, nulliparous women in their second or third trimesters with singleton pregnancies attended weekly mindfulness meditation and prenatal Hatha yoga classes in the community for 7 weeks. Sleep variables, as estimated by 72 hr of continuous wrist actigraphy and the General Sleep Disturbance Scale (GSDS), were recorded at baseline (Time 1) and postintervention (Time 2). Control data were obtained by evaluating sleep in the third-trimester group at Time 1. Due to small sample size, data were analyzed using parametric and nonparametric statistics. Women who began the intervention in the second trimester had significantly fewer awakenings, less wake time during the night, and less perceived sleep disturbance at Time 2 than at baseline. Those who began during the third trimester had poorer sleep over time in spite of the intervention. Women who began the intervention in their second trimester had less awake time at Time 2 compared to third-trimester controls at Time 1. Mindful yoga shows promise for women in their second trimester of pregnancy to diminish total number of awakenings at night and improve sleep efficiency and merits further exploration. Results from this pilot study provide the data to estimate sample size and design and implement powered and more controlled studies in the future.

The Effects of Music Relaxation on Sleep Quality and Emotional Measures in People Living with Schizophrenia

The aim of the present study was to examine the effects of music relaxation on insomnia and emotional measures in people living with schizophrenia. Twenty-four people living with schizophrenia participated in the study. The study involved a 7-day running-in no-treatment period, followed by a 7-day experimental period. Treatment consisted of music relaxation played at bedtime. During each of these periods, participants' sleep was continuously monitored with a wrist actigraph, and participants completed a wide spectrum of questionnaires. Results showed an improvement in sleep latency and sleep efficiency after the music relaxation was played. Likewise, music relaxation was shown to improve participants' total psychopathology score (PANSS) as well as their level of depression. Moreover, a significant correlation was found between reduction in level of situational anxiety and improvement in sleep efficiency. The findings suggest the beneficial effect of music relaxation as a treatment both for insomnia and for emotional measures in people living with schizophrenia.

Melatonin improves sleep and reduces nitrite in the exhaled breath condensate in cystic fibrosis – a randomized, double‐blind placebo‐controlled study

Cystic fibrosis (CF) is a chronic progressive disorder characterized by repeated episodes of respiratory infection. Impaired sleep is common in CF leading to reduced quality of life. Melatonin, a secretory product of the pineal gland, has an important function in the synchronization of circadian rhythms, including the sleep-wake cycle, and has been shown to possess significant anti-oxidant properties. To evaluate the effects of exogenous melatonin on sleep and inflammation and oxidative stress markers in CF, a randomized double-blind, placebo-controlled study initially involving 20 patients with CF was conducted. One individual failed to conclude the study. All subjects were clinically stable when studied and without recent infectious exacerbation or hospitalization in the last 30 days. Groups were randomized for placebo (n = 10; mean age 12.1 +/- 6.0) or 3 mg melatonin (n = 9; mean age 16.6 +/- 8.26) for 21 days. Actigraphy was performed for 6 days before the start of medication and in the third week (days 14-20) of treatment. Isoprostane and nitrite levels were determined in exhaled breath condensate (EBC) at baseline (day 0) and after treatment (day 21). Melatonin improved sleep efficiency (P = 0.01) and tended to improve sleep latency (P = 0.08). Melatonin reduced EBC nitrite (P = 0.01) but not isoprostane. In summary, melatonin administration reduces nitrite levels in EBC and improves sleep measures in clinically stable CF patients. The failure of melatonin to reduce isoprostane levels may have been a result of the low dose of melatonin used as a treatment.

Tolerance of Chronic 90-Minute Time-In-Bed Restriction in Older Long Sleepers

To examine the influence of chronic time-in-bed (TIB) restriction on selected health-related outcome variables in older long sleepers. Randomized, controlled trial. Home-based. Forty-two older adults (aged 50-70 y) who reported sleeping at least 8.5 hours. Following extensive screening, participants were assessed for 10 weeks. During a two-week baseline, participants followed their usual sleep-wake habits. Participants were then randomized to one of two eight-week treatments: (1) TIB restriction, in which participants were asked to follow a fixed sleep schedule with a TIB of 90 minutes less than recorded during baseline or (2) a control treatment, which involved following a fixed sleep schedule (consistent with average baseline) but no TIB restriction. Continuous wrist actigraphic sleep estimation indicated that TIB restriction elicited significant reductions in TIB and total sleep time compared with the control treatment and significant (albeit modest) improvements in sleep efficiency and sleep latency. However, compared with the control treatment, TIB restriction elicited no significant change in depression, sleepiness, health-related quality of life, or neurobehavioral performance. Moreover, follow-up assessments for one year indicated that, after completing the experiment, the participants assigned to TIB restriction continued to restrict their TIB (at their own initiative) by an average of approximately one hour. The results suggest good tolerance of chronic moderate TIB restriction, without detrimental effects, among older long sleepers.

Electroacupuncture for primary insomnia: a randomized controlled trial.

To evaluate the short-term efficacy and safety of electroacupuncture for the treatment of primary insomnia. Randomized, single-blind, placebo-controlled, parallel-group. A university-based sleep clinic. Community sample of 60 Chinese adult volunteers who report having insomnia 3 or more nights per week, whose symptoms meet the DSM-IV criteria for primary insomnia for at least 3 months, and who have an Insomnia Severity Index total score of at least 15. Participants were screened with polysomnography and the Structured Clinical Interview for the DSM-IV prior to randomization. Electroacupuncture at Yintang (EX-HN3), Baihui (GV20), bilateral ear Shenmen, Sishencong (EX-HN1), and Anmian (EX) 3 times per week for 3 weeks or placebo acupuncture using Streitberger needles at the same points. Self-reported questionnaires, 1-week sleep diaries, and 3-day actigraphy were collected at baseline and 1 week after treatment. The Insomnia Severity Index was used as the primary outcome measure. Both groups showed significant improvement compared with the pretreatment baseline. One-way analysis of covariance adjusted for baseline scores showed that there were significantly greater improvements in sleep efficiency by sleep diary and actigraphy in the electroacupuncture group. However, no significant between-group differences were observed in the Insomnia Severity Index and other outcome measures. The proportions of subjects having less than 30 minutes of wake after sleep onset and a sleep efficiency of at least 85% at the posttreatment visit were significantly higher in the electroacupuncture group. All adverse events were mild in severity. We found a slight advantage of electroacupuncture over placebo acupuncture in the short-term treatment of primary insomnia. Because of some limitations of the current study, further studies are necessary to verify the effectiveness of acupuncture for insomnia.

Improvement of Idiopathic Central Sleep Apnea with Zolpidem

We hypothesized that the non-benzodiazepine hypnotic zolpidem would improve idiopathic central sleep apnea (ICSA) by enhancing sleep stability, resulting in fewer arousals, which in turn would lessen oscillation in arterial CO2 and produce a decrease in central apnea/hypopnea events. Zolpidem might also decrease ventilatory control responsiveness during arousals, thereby reducing hyperpnea, hypocapnia, and subsequent apneas. This was a case series in which all patients with ICSA seen in the Henry Ford Sleep Disorders Clinic from January 1, 2004, to December 31, 2006, were offered zolpidem, as well as other therapeutic options of acetazolamide, continuous positive airway pressure (CPAP), bilevel pressure support, or assist control ventilatory support. Those 20 patients who chose zolpidem were prescribed 10 mg at bedtime. After a therapeutic trial averaging 9 weeks, a follow-up polysomnogram showed that the overall apnea/hypopnea index (AHI) and central AHI (CAHI) decreased, 30.0 +/- 18.1 (SD) to 13.5 +/- 13.3 (p = 0.001), and 26.0 +/- 17.2 to 7.1 +/- 11.8 (p < 0.001), respectively, without an overall change in obstructive AHI or arterial oxygen saturation. The total number of arousals per hour decreased with zolpidem use, 24.0 +/- 11.6 to 15.1 +/- 7.7 (p < 0.001), leading to a significant improvement in sleep efficiency. There was a positive correlation between the decrease in CAHI and the arousal index. Consistent with the hypnotic effect of zolpidem, sleep latency decreased, stage 1 sleep percentage decreased, and stage 2 percentage increased (all significant), without changes in stage 3-4 or REM sleep. Excessive daytime sleepiness, measured by the Epworth Sleepiness Scale (ESS) decreased from 13 +/- 5 to 8 +/- 5 (p < 0.001). Three patients experienced a significant increase in obstructive events. In an open-label trial, ICSA patients studied experienced a decrease in central apnea/hypopneas with zolpidem. They also had improved sleep continuity and decreased subjective daytime sleepiness, without a worsening of oxygenation or obstructive events in the majority of patients. However, in the absence of a randomized, controlled trial, zolpidem cannot be recommended for treatment of ICSA at this time.

Effects of Nocturnal Hemodialysis on Melatonin Rhythm and Sleep-Wake Behavior: An Uncontrolled Trial

End-stage renal disease and its treatment are associated with sleep disturbances such as deterioration of the circadian sleep-wake pattern. Melatonin rhythm, which has an important role in this pattern, is disturbed. The nocturnal melatonin surge is absent in this population. Whether nocturnal in-center hemodialysis changes melatonin and sleep-wake rhythms is unknown. A nonrandomized uncontrolled trial. Patients served as their own controls. Thirteen daytime hemodialysis patients (median age, 58 years; 5 women) from our hospital receiving conventional daytime hemodialysis 3 times weekly for 3 to 4 hours each session. Six months of treatment with nocturnal in-center dialysis 4 nights/wk with 8-hour sessions. At baseline, while still on conventional hemodialysis therapy, polysomnography was performed, sleep questionnaires were filled out, and melatonin concentration in saliva was obtained. After 6 months of in-center nocturnal hemodialysis, all measurements were repeated. After 6 months of in-center nocturnal hemodialysis, polysomnography showed significant improvements in sleep efficiency (P = 0.05) and stage 3/4 sleep (P = 0.03) in comparison to t = 0. Trends in improvement of rapid-eye-movement sleep, awake time, and oxygen saturation were seen after 6 months of in-center nocturnal hemodialysis therapy. Sleep questionnaires showed a trend in improved sleep quality and daytime function. Patients were less exhausted during the daytime. The nocturnal melatonin surge was partially restored. Small sample size and a nonrandomized uncontrolled study design. Patients after 6 months of in-center nocturnal hemodialysis had significant improvements in subjective and objective sleep parameters and partially restored nocturnal melatonin rhythm.

Self-help therapy for insomnia: A meta-analysis

Insomnia is a prevalent problem which often leads to a reduced quality of life and diminished work productivity. Only a minority of patients are treated with effective non-pharmacological therapies. A self-help intervention might offer an inexpensive and more accessible alternative to face-to-face treatment. We conducted a meta-analysis of randomized controlled studies examining the effects of self-help interventions for insomnia, identified through extensive searches of bibliographical databases. We examined the effects of self-help on different sleep outcomes, in comparison with both waiting lists controls and face-to-face treatments. Ten studies with a total of 1000 subjects were included. The intervention did improve sleep efficiency (d=0.42; p<0.05), sleep onset latency (d=0.29; p<0.05), wake after sleep onset (d=0.44; p<0.05) and sleep quality (d=0.33; p<0.05) but not total sleep time (d=0.02; p>0.05). The sleep improvements were maintained over the longer term. Symptoms of anxiety and depression also decreased after self-help (d=0.28; p<0.05 and d=0.51; p<0.05, respectively). Although based on a very limited number of studies, the face-to-face treatments did not show statistically significant superiority to the self-help treatments. The effect sizes associated with self-help treatments might be overestimated due to publication bias. The effects of self-help treatments are small to moderate. Nevertheless, they might constitute a useful addition to existing treatment options especially when integrated in a stepped care approach.

CONTINUOUS POSITIVE AIRWAY PRESSURE COMPLIANCE AND ZALEPLON

PURPOSE: Continuous positive airway pressure (CPAP) is very effective in eliminating the obstructive breathing events in patients with obstructive sleep apnea syndrome, but CPAP compliance only ranges between 29 –89%. Heated humidity, intensive education, and close follow-up have shown limited success in improving compliance. Improved sleep efficiency during the initial CPAP titration is reported to correlate with improved compliance. We hypothesized that CPAP compliance would improve by administering zaleplon, a short-acting hypnotic, to improve sleep efficiency during CPAP titration.

Eszopiclone Improves Overnight Polysomnography and Continuous Positive Airway Pressure Titration: A Prospective, Randomized, Placebo-Controlled Trial

To assess whether premedication with eszopiclone would improve sleep duration and continuity during polysomnography, thereby improving the quality of diagnostic and CPAP titration studies. Prospective, double-blinded, placebo-controlled trial Academic, multidisciplinary sleep center. 226 adult subjects undergoing polysomnography for suspected sleep disordered breathing; 113 received eszopiclone and 113 received placebo. Subjects received eszopiclone 3 mg or matching placebo before polysomnography. We compared sleep latency, efficiency, total sleep time, and apnea-hypopnea index between these groups. We also compared rates of inadequate studies, defined as insufficient sleep time (< 120 min or sleep efficiency < or = 70%) or incomplete CPAP titrations (> or = 5 events/h on the highest CPAP or complete intolerance). Eszopiclone premedication significantly improved a number of measured variables. Eszopiclone reduced sleep latency (21.7 +/- 27.1 vs. 32.6 +/- 38.2 min, P = 0.014), improved sleep efficiency (87.6% +/- 10.8% vs. 78.1% +/- 15.6%, P < 0.001), reduced wake after sleep onset (39.2 +/- 31.9 vs. 64.5 +/- 45.4 min, P <0.001) and prolonged sleep time (346.5 +/- 53.1 vs. 312.2 +/- 64.2 min, P < 0.001). Sleep efficiencies < or = 70% were more common with placebo than medication (21.2% vs. 7.1%, P = 0.004). Eszopiclone facilitated improved CPAP titrations with fewer residual events (5.7 +/- 10.3 vs. 11.9 +/- 19.6, P = 0.02) and fewer incomplete titrations (31.1% vs. 48.0%, P = 0.04). Poor quality studies (46.0% vs. 26.5%, P = 0.004) were more common with placebo than with eszopiclone. There was a trend for more non-usable studies with placebo (7.1% vs. 2.7%, P = 0.22). Side effects were uncommon and did not differ between groups. Pretreatment with eszopiclone improves the quality of polysomnography and CPAP titration and decreases the need to repeat studies. Given the ever-growing demand for polysomnography and the need to improve efficiency, the routine use of nonbenzodiazepines as premedication for polysomnography should be considered.

A proposed 24 h lighting scheme for older adults

Alzheimer's disease (AD) patients exhibit random patterns of rest and activity rather than the consolidated sleep/wake cycle found in normal, older people. Light treatment has been shown to improve rest and activity rhythms and sleep efficiency of AD patients, presumably through consolidation of their circadian rhythms. The circadian system is maximally sensitive to short-wavelength radiation. Two independent studies summarised here show that 30 lux at the cornea of blue light (λ max = 470 nm) from light emitting diodes (LEDs) for 2 h in the early evening improved sleep efficiency of older adults, including those with AD compared to exposure to the same dose of red light. Because compliance to blue light treatment may be difficult for adults with AD, we conceived of a lighting scheme that might be more practical and as effective. White light dosages of different spectra and amounts for night and for day, based on a computational model for human circadian phototransduction, might be more readily accepted by seniors and by their caregivers. Implications for an improved visual environment and for better sleep efficiency of older adults are discussed.

Effect of Surgical Weight Loss on Sleep Architecture in Adolescents with Severe Obesity

Sleep duration and sleep fragmentation have been proposed to play a role in the development and progression of obesity-associated morbidity. Weight loss results in resolution of obesity-associated morbidity. Our aim was to determine the effect of weight loss on sleep architecture in adolescents with severe obesity. Retrospective analysis of polysomnograhic data from all adolescents who underwent overnight sleep study before and after weight loss surgery was performed. Polysomnographic variables of sleep architecture after weight loss were compared to baseline by paired Student's t test (normally distributed data) or Wilcoxon test (variables not meeting normality criteria). The mean (+/-SEM) age of 19 subjects meeting inclusion criteria was 16.5 +/- 0.35 years, mean body mass index was 60.3 +/- 2.11 kg/m2, and 66% were female. Obstructive sleep apnea was present in 14 subjects (74%). The average interval between the baseline and repeat polysomnograms was 0.91 +/- 0.16 years, and average weight loss was 66.4 +/- 8.8 kg. Surgical weight loss resulted in increased sleep efficiency (80.2% vs 73.1%, p = 0.01), reduced time in stage 1 sleep (3.0% vs 6.0%, p = 0.02), and reduced arousal index (7.6 +/- 0.6/h vs 11.3 +/- 1.2, p = 0.01). Our data demonstrate a marked improvement in sleep efficiency and sleep fragmentation with surgical weight loss. Given the emerging evidence that surgical weight loss results in resolution of obesity-associated psychosocial, metabolic, and cardiovascular morbidity, these results suggest that correction of sleep fragmentation could be an important but as yet underappreciated factor influencing changes in these other major comorbidities of obesity.

Therapeutic potential of melatonin agonists

Melatonin, a hormone secreted by the pineal gland, has been successfully employed to improve sleep in both normal patients and insomniacs, and for the treatment of circadian rhythm sleep disorders. Melatonergic MT1 and MT2 receptors exist in high concentrations in the suprachiasmatic nucleus of the hypothalamus and have been shown to be instrumental for the sleep-promoting and circadian rhythm-regulating effects of melatonin. A lack of consistency among reports on the therapeutic efficacy of melatonin has been attributed to differences in melatonin’s bioavailability and the short half-life of the hormone. In view of the need for longer acting melatonergic agonists that improve sleep efficiency without causing drug abuse or dependency, ramelteon (Rozerem™, Takeda) was developed. Ramelteon, which acts via MT1/MT2 melatonergic agonism, has been found clinically effective for improving total sleep time and sleep efficiency in insomniacs. Agomelatine (Valdoxan™, Servier) is another MT1/MT2 melatonergic agonist that also displays antagonist activity at 5-HT2C serotonin receptors. Agomelatine has been found effective in treating depression and sleep disorders in patients with major depressive disorder. A slow-release preparation of melatonin (Circadin™, Neurim) has been shown to be effective in treating sleep disorders in the elderly population.