The exploratory power of sleep effort,dysfunctional beliefs and arousal for insomnia severity and polysomnography‐determined sleep

Differences between subjective sleep perception and sleep determined by polysomnography (PSG) are prevalent, particularly in patients with primary insomnia, indicating that the two measures are partially independent. To identify individualized treatment strategies, it is important to understand the potentially different mechanisms influencing subjective and PSG‐determined sleep. The aim of this study was to investigate to what extent three major components of insomnia models, i.e. sleep effort, dysfunctional beliefs and attitudes about sleep, and presleep arousal, are associated with subjective insomnia severity and PSG‐ determined sleep. A sample of 47 patients with primary insomnia according to DSM‐IV criteria and 52 good sleeper controls underwent 2 nights of PSG and completed the Glasgow Sleep Effort Scale, the Dysfunctional Beliefs and Attitudes about Sleep Scale, the Pre‐Sleep Arousal Scale and the Insomnia Severity Index. Regression analyses were conducted to investigate the impact of the three predictors on subjective insomnia severity and PSG‐ determined total sleep time. All analyses were adjusted for age, gender, depressive symptoms and group status. The results showed that subjective insomnia severity was associated positively with sleep effort. PSG‐determined total sleep time was associated negatively with somatic presleep arousal and dysfunctional beliefs and attitudes about sleep. This pattern of results provides testable hypotheses for prospective studies on the impact of distinct cognitive and somatic variables on subjective insomnia severity and PSG‐determined total sleep time.     

NREM sleep EEG frequency spectral correlates of sleep complaints in primary insomnia subtypes

STUDY OBJECTIVES: To determine whether the frequency spectrum of the sleep EEG is a physiologic correlate of 1) the degree to which individuals with persistent primary insomnia (PPI) underestimate their sleep time compared with the traditionally scored polysomnogram (PSG) and 2) the sleep complaints in PPI subjects who have relatively long traditionally scored PSG sleep times and relatively greater underestimation of sleep time. DESIGN: We compared EEG frequency spectra from REM and NREM sleep in PPI subjects subtyped as subjective insomnia sufferers (those with relatively long total sleep time and relative underestimation of sleep time compared with PSG), and objective insomnia sufferers (those with relatively short PSG total sleep time) with EEG frequency spectra in normals. We also studied the correlation between these indices and the degree of underestimation of sleep. Further, we determined the degree to which sleep EEG indexes related to sleep complaints. SETTING: Duke University Medical Center Sleep Laboratory. PARTICIPANTS: Normal (N=20), subjective insomnia (N=12), and objective insomnia (N=18) subjects. INTERVENTIONS: N/A MEASUREMENTS AND RESULTS: Lower delta and greater alpha, sigma, and beta NREM EEG activity were found in the patients with subjective insomnia but not those with objective insomnia, compared with the normal subjects. These results were robust to changes in the subtyping criteria. No effects were found for REM spectral indexes. Less delta non- REM EEG activity predicted greater deviation between subjective and PSG estimates of sleep time across all subjects. For the subjective insomnia subjects, diminished low-frequency and elevated higher frequency non- REM EEG activity was associated with their sleep complaints. CONCLUSIONS: NREM EEG frequency spectral indexes appear to be physiologic correlates of sleep complaints in patients with subjective insomnia and may reflect heightened arousal during sleep.     

Comparison of actigraphy with polysomnography and sleep logs in depressed insomniacs

Actigraphy is increasingly used in the assessment and treatment of various clinical conditions, being a convenient and cost‐effective method of capturing bodily movements over long periods of time. This study examined the use of actigraphy in the measurement of sleep of patients with depression and insomnia. Fifty‐four patients diagnosed with a current major depressive episode and chronic insomnia underwent a baseline overnight study with concurrent actigraphic and polysomnography (PSG) monitoring, as well as subjective sleep diaries. Agreement between PSG, actigraphy and sleep diary measurements was evaluated using two‐tailed t‐tests, Pearson’s correlations and the Bland–Altman concordance technique. The only significant difference found between actigraphy and PSG was in latency to persistent sleep, in which actigraphy underestimated sleep latency relative to PSG (P < 0.05). There were moderate positive correlations between actigraphy and PSG for all variables. In contrast, significant differences were observed between sleep diaries and PSG for all sleep variables. Bland–Altman concordance diagrams also demonstrated that, while bias was limited between PSG and the other two measurement types, there were somewhat broad 95% limits of agreement for all sleep variables with both sleep diaries and actigraphy. In summary, actigraphic measurements of sleep more closely approximated those of PSG than did sleep diaries in this sample of depressed insomniacs.     

主诉失眠的门诊就诊者主客观评估的睡眠质量与生命质量

目的:失眠者的主观睡眠感与实际睡眠情况常有不一致的现象,本研究通过探讨以失眠为主诉的门诊就诊者睡眠质量的主观、客观评估指标与生命质量的相关性,为临床制定失眠的整体治疗方案提供参考依据。方法:连续收集64例以失眠为主诉的接受多导睡眠图(PSG)检查的门诊患者的资料,用匹兹堡睡眠质量指数(PSQI)评估主观睡眠质量,SF-36健康调查量表评估生命质量,用贝克抑郁问卷(BDI)、贝克焦虑问卷(BAI)评估情绪状态。以17例正常人的PSG数据作为客观睡眠质量的基础对照。结果:本组失眠就诊者90%主观评价睡眠质量差,其PSG指标中与正常对照相比睡眠潜伏期延长、清醒次数增加、睡眠效率降低、快动眼睡眠潜伏期延长(均P<0.05)。失眠就诊者PSQI总分与SF-36生理健康总分呈负相关(r=-0.25,P<0.05),但以BDI、BAI分作为控制变量进行偏相关分析显示,PSQI总分及各因子分与SF-36生理健康和心理健康总分相关性无统计学意义;PSG主要指标与SF-36生理健康和心理健康总分相关性无统计学意义。结论:本研究显示失眠者主观感受的睡眠质量更可能与生命质量相关,但与失眠相关的抑郁、焦虑情绪可能起到主要作用,这提示失眠治疗中应重视改善患者的主观睡眠质量,以及识别和处理情绪问题。     

Actigraphy in studies on insomnia: Worth the effort?

In the past decades, actigraphy has emerged as a promising, cost-effective, and easy-to-use tool for ambulatory sleep recording. Polysomnography (PSG) validation studies showed that actigraphic sleep estimates fare relatively well in healthy sleepers. Additionally, round-the-clock actigraphy recording has been used to study circadian rhythms in various populations. To this date, however, there is little evidence that the diagnosis, monitoring, or treatment of insomnia can significantly benefit from actigraphy recordings. Using a case–control design, we therefore critically examined whether mean or within-subject variability of actigraphy sleep estimates or circadian patterns add to the understanding of sleep complaints in insomnia. We acquired actigraphy recordings and sleep diaries of 37 controls and 167 patients with varying degrees of insomnia severity for up to 9 consecutive days in their home environment. Additionally, the participants spent one night in the laboratory, where actigraphy was recorded alongside PSG to check whether sleep, in principle, is well estimated. Despite moderate to strong agreement between actigraphy and PSG sleep scoring in the laboratory, ambulatory actigraphic estimates of average sleep and circadian rhythm variables failed to successfully differentiate patients with insomnia from controls in the home environment. Only total sleep time differed between the groups. Additionally, within-subject variability of sleep efficiency and wake after sleep onset was higher in patients. Insomnia research may therefore benefit from shifting attention from average sleep variables to day-to-day variability or from the development of non-motor home-assessed indicators of sleep quality.     

失眠症患者的多导睡眠图改变及应对措施

目的 探讨失眠症患者的多导睡眠图(PSG)改变及应对措施。方法 对29例失眠症患者和22例正常人进行整夜多导睡眠图(PSG)描记并比较,同时对失眠患者指导实施应对措施。结果 失眠症患者有睡眠潜伏期(SL)显著延长,睡眠效率(SE)明显降低,觉醒次数(AT)增多,实际睡眠时间(TST)减少,自我评估与实际睡眠时间相差较大。结论 失眠症患者应采取应对措施,改变睡眠结构,提高睡眠质量。     

Wrist actigraphy in insomnia.

To assess the use of actigraphy in evaluating insomnia, 36 patients with a serious complaint of insomnia slept 3 nights each in the laboratory, where the usual polysomnograms (PSGs) were obtained as well as actigraphic assessments of their sleep. Patients also wore actigraphs for 7 days at home, were extensively interviewed and filled out psychometric tests. Based on all this information, the patients were then diagnosed according to the International Classification of Sleep Disorders. Averaged over the 3 nights for each insomniac, the mean discrepancy between actigram and PSG was 49 minutes per night. In three-fourths of the cases, actigram and PSG agreed to within 1 hour on the total amount of sleep per night. Discrepancies, however, were not random: In patients with psychophysiologic insomnia and in insomnia associated with psychiatric disease, the actigram typically overestimated sleep when compared with the PSG. In patients with sleep-state misperception, the actigram was either quite accurate or it underestimated sleep when compared with the PSG. Comparing laboratory with home sleep, one-third of all insomniacs slept better in the laboratory and two-thirds slept better at home. In addition, night-by-night variability was higher at home than in the laboratory. Based on our study, we now recommend actigraphy as an additional tool in the clinical evaluation of insomnia, but we believe that in complex cases it should be combined with 1 PSG night in the sleep disorders center.     

Psychophysiological insomnia: the behavioural model and a neurocognitive perspective

A number of paradoxes are apparent in the assessment and treatment of psychophysiological insomnia and sleep state misperception. Three of these paradoxes exist as discrepancies between polysomnographic (PSG) measures and the subjective impressions regarding sleep quality and quantity. The remaining incongruity exists largely within the objective domain. In the case of subjective–objective discrepancies, patients with insomnia: (1) frequently identify themselves as having been awake when awakened from PSG defined sleep; (2) tend to overestimate sleep latency and underestimate total sleep time as compared with PSG measures; (3) appear to derive more benefit from pharmacotherapy that can be explained by objective gains. The remaining paradox pertains to the observation that hypnotic medications, by and large, do not normalize sleep architecture or produce a more ‘sleep-like’ EEG. In this paper, we review possible explanations for these various paradoxes, introduce a new perspective and suggest possible research avenues. The model introduced is based on the observation that beta and/or gamma activity (which have been found to be associated with cognitive processes) is enhanced in insomnia at or around sleep onset. We propose that this kind of high frequency EEG activity may interfere with the normal establishment of sleep onset-related mesograde amnesia. As a result, the patient with insomnia maintains a level of information and/or memory processing that blurs the phenomenological distinction between sleep and wakefulness and influences retrospective judgments about sleep initiation and duration.     

Daytime testing after laboratory or home-based polysomnography: comparisons of middle-aged insomnia sufferers and normal sleepers

Many studies have shown only modest differences between insomnia sufferers and matched, non-complaining normal controls in regard to their levels of daytime sleepiness and diurnal performances. The current study was conducted to determine whether such daytime comparisons might be affected by the setting (home vs. sleep lab) in which study participants sleep on the nights before such testing. The study used a counter-balanced, matched-group design in which participants underwent three consecutive nocturnal polysomnographs (PSG) conducted either in the sleep lab or in their homes prior to undergoing daytime multiple sleep latency test (MSLT) and computer-administered performance testing. The study participants were 35 (18 women and 17 men) middle-aged (40-59 years) non-complaining normal sleepers and 33 middle-aged insomnia sufferers (17 women and 16 men) who met structured interview criteria for persistent primary insomnia. Use of a hierarchical linear statistical model showed only insomnia sufferers who underwent nocturnal home PSG were more alert on the MSLT than were normal sleepers who underwent lab PSG. However, these insomnia sufferers showed a greater propensity toward attention lapses on selected reaction time tests than did either of the two normal control groups (i.e. either those who slept in the lab or those who slept at home). The results suggest the nocturnal sleep setting (home vs. lab) may affect subsequent MSLT and performance test comparisons of insomnia sufferers and normal sleepers.     

Does REM sleep contribute to subjective wake time in primary insomnia? A comparison of polysomnographic and subjective sleep in 100 patients

Primary insomnia (PI) is characterized by low subjective sleep quality which cannot always be verified using polysomnography (PSG). To shed light on this discrepancy, subjective estimates of sleep and PSG variables were compared in patients with PI and good sleeper controls (GSC). 100 patients with PI (age: 42.57 +/- 12.50 years, medication free for at least 14 days) and 100 GSC (41.12 +/- 13.99 years) with a sex distribution of 46 men and 54 women in each group were included. Both PSG and questionnaire variables showed clear impairments of sleep quality in PI compared with GSC. The arousal index within total sleep time was increased, which was mainly because of a strong increase within rapid eye movement (REM) sleep. Subjectively, more PI than GSC subjects estimated wake times longer than obtained from PSG. Linear modeling analysis of subjective wake time in terms of PSG parameters revealed that in addition to PSG defined wake time, REM sleep time contributed significantly to subjective wake time. This REM sleep contribution was larger for PI than for GSC subjects. The findings suggest that REM sleep-related processes might contribute to subjectively disturbed sleep and the perception of waking time in patients with PI.     

Polysomnographic assessment of DIMS: empirical evaluation of its diagnostic value

This investigation examined the diagnostic value of polysomnography (PSG) for evaluating disorders of initiating and maintaining sleep (DIMS). The sample consisted of 100 outpatients who presented to the Duke Sleep Disorders Center with a complaint of chronic insomnia. All patients were given comprehensive medical, psychiatric, behavioral, and ambulatory PSG evaluations. Sleep disorder diagnoses were assigned using the criteria of the Association of Sleep Disorders Centers. Overall, PSG yielded important diagnostic information in 65% of the sample: 34% were given a primary sleep disorder diagnosis that was heavily dependent on PSG data [periodic movements of sleep (PMS) = 25%, apnea = 3%, and subjective insomnia = 6%]; 15% were given a secondary diagnosis of one of these three disorders; and PSG ruled out suspected PMS in 9% and sleep apnea in 7% of the sample. Patients greater than 40 years of age had a significantly higher rate of positive PSG findings than younger patients. Using only the clinical exam, two experienced sleep clinicians were able to predict only 14 of 25 PMS cases and one of three cases of sleep apnea. Based on these data, we suggest using PSG routinely with older insomniacs and with younger patients who fail initial treatment.     

Low-dose sublingual zolpidem tartrate is associated with dose-related improvement in sleep onset and duration in insomnia characterized by middle-of-the-night (MOTN) awakenings

STUDY OBJECTIVES: To evaluate the efficacy and safety of low-dose, sublingual zolpidem tartrate when taken during a scheduled middle-of-the-night (MOTN) awakening in subjects with insomnia characterized by difficulty returning to sleep following MOTN awakenings. DESIGN: Randomized, double-blind, placebo-controlled, 3-way crossover study. METHODS: Each treatment period consisted of 2 consecutive nights of dosing separated by a washout of 5 to 12 days. Subjects were awakened 4 h after lights out, dosed with sublingual zolpidem tartrate (3.5 mg or 1.75 mg) or placebo, kept awake for 30 min, and then returned to bed for an additional 4 h. Sleep parameters were assessed by polysomnography (PSG) and post-sleep questionnaires. SETTING: Five sleep laboratories. PARTICIPANTS: Adults (24 males, 58 females, mean age 45.9 y) with a diagnosis of DSM-IV primary insomnia and a history of prolonged MOTN awakenings. Baseline difficulties with MOTN awakenings were confirmed by a 10-day screening sleep diary and PSG screening. RESULTS: Low-dose sublingual zolpidem tartrate demonstrated significant dose-related decreases in latency to persistent sleep and total sleep time (P < 0.001) compared to placebo after MOTN dosing. All subject reports paralleled PSG observations. Neither dose showed next-morning impairment on the DSST or ratings of sleepiness. The 3.5-mg dose produced improvements in reports of sleep quality (P < 0.001), ability to function, and level of refreshed sleep (P < 0.05 for both dosages) compared to placebo. Sublingual zolpidem tartrate lozenges were generally safe and well tolerated. CONCLUSIONS: Low-dose sublingual zolpidem tartrate may be suitable for treatment of patients who have difficulty resuming sleep after MOTN awakenings.     

Stress exposure,psychological distress,and physiological stress activation in midlife women with insomnia

OBJECTIVE: The objective of this study was to describe perceived and polysomnograhic (PSG) sleep patterns and determine whether stress exposure, psychological distress, and physiological stress activation differed among midlife women with psychophysiologic-type (PP-type) or subjective only-type (SO-type) insomnia or no insomnia. METHODS: Women had their sleep monitored, collected urine samples, and completed questionnaires in a week-long field study, and 53 women met criteria for insomnia types or no insomnia based on reported sleep quality and PSG sleep efficiency. RESULTS: As expected, women with PP-type insomnia were found to have the lowest sleep efficiency, took longer to fall asleep, had more wakefulness after sleep onset, and had more fragmented sleep. Perceptions of stress exposure, either for major or minor events, did not differ among groups. Despite there being no differences in perceived stress exposure, women with both types of insomnia scored higher on psychological distress (SCL-90R), especially on the somatization subscale, than women with no insomnia. Of the physiological stress activation indicators tested, a morning-to-evening difference in urinary cortisol statistically differed across the groups (p <.005). Women in the PP-type insomnia group had the highest levels of urinary cortisol in an early morning urine sample. CONCLUSIONS: These data provide support for the hypothesis that, in midlife women, cognitive or emotional arousal with chronic stress neuroendocrine activation underlies chronic insomnia, particularly the PP-type.     

Sleep perception and the multiple sleep latency test in patients with primary insomnia

The purpose of this study was to examine the relationship between overnight sleep perception and the daytime multiple sleep latency test (MSLT) among individuals who were primary insomnia patients (PIPs) or good sleeper controls (GSCs). We collected overnight sleep data via polysomnography (PSG), subjective sleep data via a morning questionnaire (self‐evaluated) and MSLT data via four 20‐min naps over 8 h. Subjects included 122 PIPs and 48 GSCs. Sleep perception was calculated as subjective sleep time/objective sleep time × 100%. PIPs showed a significant difference (P < 0.001) between sleep time, as determined by PSG (387.8 ± 100 min) and self‐report (226.3 ± 160 min), but no difference was obtained for GSCs (440.6 ± 53 versus 435.4 ± 65 min). The means for sleep perception were 56.4 ± 38.8% for the PIPs and 99.3 ± 13.6% for the GSCs (P < 0.001). In the PIPs group, weak but statistically significant negative correlations (r: ?0.20 to ?0.25) were found for MSLT versus sleep perception and versus self‐ and PSG‐evaluated sleep time. Compared to PIPs with low scores on the MSLT, those with high scores had less sleep perception (%), less self‐ and PSG‐evaluated sleep time and greater sleep misperception time. GSCs did not show significant correlations between MSLT and sleep measures or differences in comparisons between individuals with high and low scores on the MSLT. These results add novel data to the literature by suggesting that 24‐h hyperarousal potentially plays a key role in the pathophysiological issues of insomnia.     

Do patients with sleep maintenance insomnia have a problem with sleep maintenance?

Do patients with primary insomnia differ from good sleepers with respect to the number or duration of awakenings or to the stages from which awakenings occur? To address this question, polysomnography (PSG) records were evaluated in 10 good sleepers (GS) and 10 primary insomnia patients (PI). PSG records were evaluated for occurrence and duration of awakenings and for the stage immediately preceding each awakening. PIs woke more frequently and for longer durations than did GSs. PIs' awakenings tended to occur from Stages 1 or 2; GSs' occurred from epochs scored as movement times. The data from this study represent the first attempt to characterize the stages from which awakenings occur in sleep maintenance insomnia.     

Insomnia and sleep misperception

Sleep misperception is often observed in insomnia individuals (INS). The extent of misperception varies between different types of INS. The following paper comprised sections which will be aimed at studying the sleep EEG and compares it to subjective reports of sleep in individuals suffering from either psychophysiological insomnia or paradoxical insomnia and good sleeper controls. The EEG can be studied without any intervention (thus using the raw data) via either PSG or fine quantitative EEG analyses (power spectral analysis [PSA]), identifying EEG patterns as in the case of cyclic alternating patterns (CAPs) or by decorticating the EEG while scoring the different transient or phasic events (K-Complexes or sleep spindles). One can also act on the on-going EEG by delivering stimuli so to study their impact on cortical measures as in the case of event-related potential studies (ERPs). From the paucity of studies available using these different techniques, a general conclusion can be reached: sleep misperception is not an easy phenomenon to quantify and its clinical value is not well recognized. Still, while none of the techniques or EEG measures defined in the paper is available and/or recommended to diagnose insomnia, ERPs might be the most indicated technique to study hyperarousal and sleep quality in different types of INS. More research shall also be dedicated to EEG patterns and transient phasic events as these EEG scoring techniques can offer a unique insight of sleep misperception.     

Relation between ambulatory actigraphy and laboratory polysomnography in insomnia practice and research

Actigraphy is increasingly used in practice and research studies because of its relative low cost and decreased subject burden. How multiple nights of at‐home actigraphy compare to one independent night of in‐laboratory polysomnography (PSG) has not been examined in people with insomnia. Using event markers (MARK) to set time in bed (TIB) compared to automatic program analysis (AUTO) has not been systematically evaluated. Subjects (n = 30) meeting DSM‐5 criteria for insomnia and in‐laboratory PSG sleep efficiency (SE) of <85% were studied. Subjects were free of psychiatric, sleep or circadian disorders, other chronic conditions and medications that effect sleep. Subjects had an in‐laboratory PSG, then were sent home for 7 nights with Philips Actiwatch Spectrum Plus. Data were analysed using Philips Actiware version 6. Using the mean of seven nights, TIB, total sleep time (TST), SE, sleep‐onset latency (SOL) and wake after sleep onset (WASO) were examined. Compared to PSG, AUTO showed longer TIB and TST and less WASO. MARK only differed from PSG with decreased WASO. Differences between the PSG night and the following night at home were found, with better sleep on the first night home. Actigraphy in people with insomnia over seven nights is a valid indicator of sleep compared to an independent in‐laboratory PSG. Event markers increased the validity of actigraphy, showing no difference in TIB, TST, SE and SOL. AUTO was representative of SE and SOL. Increased SE and TST without increased TIB suggests possible compensatory sleep the first at night home after in‐laboratory PSG.     

Do Patients With Sleep Maintenance Insomnia Have a Problem With Sleep Maintenance?

Do patients with primary insomnia differ from good sleepers with respect to the number or duration of awakenings or to the stages from which awakenings occur? To address this question, polysomnography (PSG) records were evaluated in 10 good sleepers (GS) and 10 primary insomnia patients (PI). PSG records were evaluated for occurrence and duration of awakenings and for the stage immediately preceding each awakening. PIs woke more frequently and for longer durations than did GSs. PIs' awakenings tended to occur from Stages 1 or 2; GSs' occurred from epochs scored as movement times. The data from this study represent the first attempt to characterize the stages from which awakenings occur in sleep maintenance insomnia.     

Subjective versus objective evaluation of hypnotic efficacy: experience with zolpidem.

There is little published literature on the correlation between subjective and objective efficacy of hypnotics. We wanted to determine whether there was a correlation between the patient's subjective evaluation of the efficacy of the hypnotic with the polysomnographic (PSG) findings. We studied 16 patients with chronic insomnia (sleep latency, greater than or equal to 30 minutes; total sleep time, greater than 240 but less than 420 minutes) for 11 nights who took placebos on nights 1 and 2, zolpidem (imidazopyridine) on nights 3-9 and placebo on nights 10 and 11. Patients completed a questionnaire each morning following PSG, which evaluated subjective sleep quality, sleep latency and total sleep time. These data were compared to PSG findings to answer specific questions about sleep latency reduction, efficacy of the hypnotic after a week's use, sleep quality after discontinuing the drug, and any correlation between subjective and objective measures. PSG findings indicated a shortened sleep latency, increased total sleep time, decreased total wake time and increased sleep efficiency when patients ingested zolpidem 30 minutes before bedtime. We found that after 7 nights (nights 3-9) the drug was still effective in reducing sleep latency and increasing total sleep time. Upon withdrawal (nights 10 and 11) sleep returned to baseline (nights 1 and 2). Subjectively, the patients confirmed those findings on the questionnaire, as well as a subjective reduction in the number of awakenings and, interestingly, a subjective increase in the time spent awake after sleep. Many of the objective variables we examined correlated highly with the subjective variables. While on zolpidem, subjects believed and were objectively shown to have a decreased sleep latency, increased total sleep time and decreased time awake before persistent sleep, although they tended to overestimate sleep latency and time spent awake before persistent sleep and underestimated total sleep time. Although the correlation between objective and subjective measures was high for the group, in individual patients there was an impressive difference between the two, and the highest coefficient of variation between a subjective and objective measures was 0.453. No correlations were found with subjective measures of refreshing quality of sleep, decrease in number of awakenings, how sleepy patients felt in the morning or their ability to concentrate in the morning. Thus, we believe the PSG remains the keystone in the evaluation of hypnotic efficacy.     

Nonpharmacologic treatment of chronic insomnia. An American Academy of Sleep Medicine review

This paper reviews the evidence regarding the efficacy of nonpharmacological treatments for primary chronic insomnia. It is based on a review of 48 clinical trials and two meta-analyses conducted by a task force appointed by the American Academy of Sleep Medicine to develop practice parameters on non-drug therapies for the clinical management of insomnia. The findings indicate that nonpharmacological therapies produce reliable and durable changes in several sleep parameters of chronic insomnia sufferers. The data indicate that between 70% and 80% of patients treated with nonpharmacological interventions benefit from treatment. For the typical patient with persistent primary insomnia, treatment is likely to reduce the main target symptoms of sleep onset latency and/or wake time after sleep onset below or near the 30-min criterion initially used to define insomnia severity. Sleep duration is also increased by a modest 30 minutes and sleep quality and patient's satisfaction with sleep patterns are significantly enhanced. Sleep improvements achieved with these behavioral interventions are sustained for at least 6 months after treatment completion. However, there is no clear evidence that improved sleep leads to meaningful changes in daytime well-being or performance. Three treatments meet the American Psychological Association (APA) criteria for empirically-supported psychological treatments for insomnia: Stimulus control, progressive muscle relaxation, and paradoxical intention; and three additional treatments meet APA criteria for probably efficacious treatments: Sleep restriction, biofeedback, and multifaceted cognitive-behavior therapy. Additional outcome research is needed to examine the effectiveness of treatment when it is implemented in clinical settings (primary care, family practice), by non-sleep specialists, and with insomnia patients presenting medical or psychiatric comorbidity.