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Actigraphy has been used for more than 60 years to objectively measure sleep–wake rhythms. Improved modern devices are increasingly employed to diagnose sleep medicine disorders in the clinical setting. Although less accurate than polysomnography, the chief advantage of actigraphs lies in the cost-effective collection of objective data over prolonged periods of time under everyday conditions. Since the cost of wrist actigraphy is not currently reimbursed, this method has not enjoyed wide acceptance to date. The present article provides an overview of the main clinical applications of actigraphy, including the recommendations of specialist societies.

Nocturnal Continuous Positive Airway Pressure (CPAP) is considered the gold standard treatment for obstructive sleep apnoea (OSA). The CPAP therapy is a long-term treatment but does come with few possible side effects. The adherence to the therapy is frequently suboptimal. In this paper, adherence to therapy was assessed and typical problems were classified. 1078 OSA patients received CPAP therapy after a diagnostic polygraphy (PG) or polysomnography (PSG). Adherence to therapy was followed up three months after treatment induction. The following therapy adherence groups were defined: 1. correctly calibrated CPAP and good adherence, 2. CPAP non-acceptance, after initial use, 3. CPAP intolerance use due to side effects, 4. discontinuation due to lack of motivation/low rates of symptoms. 5. mask intolerance, 6. CPAP failure due to a lack of perceived treatment effect, 7. Change to another non-invasive ventilation method, 8. No control carried out. Out of 1078 OSA patients a therapy control was performed in 830 patients (77 %). Of these, 450 patients (54.2 %) were placed in group 1, 216 patients (26 %) in group 2, 71 patients (8.5 %) in group 3, 35 patients (4.2 %) in group 4, 14 patients (1.7 %) in group 5, 3 patients (0.4 %) in group 6 and 41 patients (4.9 %) in group 7. A mild obstructive index, low CPAP pressure and, as a trend, a low Epworth- Sleepiness score were predictors of CPAP failure. No significant predictors could be shown for adherence to therapy. An effective treatment use of 54 % after 3 months is a suboptimal result. Predictors of CPAP failure were parameters that indicated that the patient was less symptomatic prior to therapy. Despite a large patient cohort, neither anthropometric nor PSG-data provided any significant CPAP adherence predictors. Rather, experiences in the first nights of use could be decisive. CPAP devices offer comfort settings that have to be personalised to patients' needs and wants. A large selection of different mask shapes requires experience and training in patient-centred mask fitting. A three-month follow-up appointment seems too long to discuss therapy problems with the patient in a timely manner. Telemedical options or short-term telephone appointments should be considered. Die nächtliche kontinuierliche positive Überdruckatmung (CPAP) gilt als therapeutischer Goldstandard einer obstruktiven Schlafapnoe (OSA). Die CPAP-Therapie stellt zumeist eine Dauertherapie mit geringen Nebenwirkungen dar. Trotzdem ist die Therapietreue unbefriedigend. In dieser Arbeit wurden die Therapietreue betrachtet und typische Probleme katalogisiert. 1078 OSA-Patienten wurden nach diagnostischer Polygrafie (PG) oder Polysomnografie (PSG) auf eine CPAP-Therapie eingestellt. Die Therapietreue wurde nach 3 Monaten nachverfolgt. Folgende Therapieadhärenz-Gruppen wurden festgelegt: 1. gute CPAP-Einstellung und Nutzung, 2. CPAP-Abbruch nach anfänglicher Nutzung, 3. mangelnde CPAP-Nutzung wegen Nebenwirkungen, 4. Abbruch aufgrund fehlender Motivation/geringem Leidensdruck, 5. Masken-Unverträglichkeit, 6. CPAP-Versagen aufgrund fehlenden Therapieeffekts, 7. Umstellung auf anderes Beatmungsverfahren, 8. keine Kontrolle erfolgt. Von 1078 CPAP-Patienten erschienen 830 Patienten (77 %) zur Therapiekontrolle. Hiervon waren 450 Patienten (54,2 %) in Gruppe 1, 216 Patienten (26 %) in Gruppe 2, 71 Patienten (8,5 %) in Gruppe 3, 35 Patienten (4,2 %) in Gruppe 4, 14 Patienten (1,7 %) in Gruppe 5, 3 Patienten (0,4 %) in Gruppe 6 und 41 Patienten (4,9 %) in Gruppe 7. Ein geringer obstruktiver Ereignisindex, niedriger CPAP-Druck und tendenziell auch ein geringer Epworth-Sleepiness-Score waren Prädiktoren für CPAP-Versagen. Für die Therapietreue konnten keine signifikanten Prädiktoren dargestellt werden. Eine effektive Therapienutzung von 54 % nach 3 Monaten ist ein suboptimales Ergebnis. Prädiktoren für CPAP-Versagen waren Parameter, die vor Therapie auf geringen Leidensdruck der Patienten deuteten. Trotz großer Patientenkohorte konnten keine signifikanten CPAP-Adhärenz-Prädiktoren durch anthropometrische oder PSG-Daten dargestellt werden. Vielmehr könnten Erfahrungen in den ersten Therapietagen ausschlaggebend sein. CPAP-Geräte bieten Komforteinstellungen, die kenntnisgerecht auf den Patienten individualisiert werden müssen. Eine große Auswahl an unterschiedlichen Maskenformen erfordert Erfahrung und Training bei der patientenorientierten Maskenanpassung. Eine 3-monatige Wiedervorstellung erscheint zu lang, um Therapieprobleme zeitnah mit dem Patienten zu besprechen. Telemedizinische Möglichkeiten oder kurzfristige telefonische Beratungsoptionen sollten in Betracht gezogen werden.

Excessive daytime sleepiness is a common symptom in obese patients with obstructive sleep apnea. We investigated predisposing factors of excessive daytime sleepiness by comparing obese non-sleepy with sleepy patients with obstructive sleep apnea. Excessive daytime sleepiness was determined by the Epworth Sleepiness Scale in 43 patients (34 men and 9 women) with obstructive sleep apnea (apnea-hypopnea index ≥ 15 events per hr) and obesity (body mass index ≥ 30 kg m-2 ). Two subgroups were formed with (Epworth Sleepiness Scale ≥ 11) and without (Epworth Sleepiness Scale

Healthy sleep, positive general affect, and the ability to regulate emotional experiences are fundamental for well-being. In contrast, various mental disorders are associated with altered rapid eye movement (REM) sleep, negative affect, and diminished emotion regulation abilities. However, the neural processes mediating the relationship between these different phenomena are still not fully understood. In the present study of 42 healthy volunteers, we investigated the effects of selective REM sleep suppression (REMS) on general affect, as well as on feelings of social exclusion, cognitive reappraisal (CRA) of emotions, and their neural underpinnings. Using functional magnetic resonance imaging we show that, on the morning following sleep suppression, REMS increases general negative affect, enhances amygdala responses and alters its functional connectivity with anterior cingulate cortex during passively experienced experimental social exclusion. However, we did not find effects of REMS on subjective emotional ratings in response to social exclusion, their regulation using CRA, nor on functional amygdala connectivity while participants employed CRA. Our study supports the notion that REM sleep is important for affective processes, but emphasizes the need for future research to systematically investigate how REMS impacts different domains of affective experience and their neural correlates, in both healthy and (sub-)clinical populations.

Objective Recent studies have suggested that patients with obstructive sleep apnea (OSA) might be affected by olfactory impairment. However, more evidence is needed on the effect that OSA has on the chemical senses (olfaction and gustatory) of these patients, and whether continuous positive airway pressure (CPAP) treatment might help to reverse possible impairment. Methods A prospective study was conducted with 44 OSA patients (17 female and 27 male, mean age 54 ± 9.9 years) who were diagnosed via polysomnography and eligible for CPAP treatment. Orthonasal olfactory and gustatory function was measured with the extended Sniffin' Sticks test battery and "taste strips," respectively, before and after CPAP treatment. Results Baseline olfaction was decreased in OSA patients and after CPAP therapy olfactory scores (odor threshold-discrimination-identification score [TDI]: baseline 29.4 ± 4.11 after CPAP 32.3 ± 4.82; p = 0.001; odor threshold [THR]: baseline 5.28 ± 1.69 after CPAP 6.78 ± 2.61; p = 0.000; odor identification [ID]: baseline 12.9 ± 1.95 after CPAP 13.6 ± 1.33; p = 0.013) improved significantly. In contrast, neither baseline taste function in OSA patients nor gustatory function after treatment seemed to be affected. Conclusion Orthonasal olfactory function in patients with OSA improves under CPAP therapy; however, gustatory function is not impaired in OSA patients.

Objective A new and unique methodology was developed to evaluate the association between periodic limb movements (PLMs) and nocturnal blood pressure (BP) excursions in patients with restless legs syndrome (RLS). Methods All data were collected at baseline of the ENCORE (Effects of Neupro on Cardiovascular Observations in Patients with Restless Legs Syndrome) study, a placebo-controlled polysomnographic study of rotigotine in patients with idiopathic RLS. Continuous beat-by-beat BP and heart rate assessments were performed during a full night of polysomnography. All BP elevations occurring with and without PLMs were systematically identified and analyzed. Results Patients ( n = 89) had a mean total of 508.9 ± 405.7 PLMs, 788.4 ± 261.9 systolic BP elevations, and 349.7 ± 242.9 diastolic BP elevations during the night. Higher time-adjusted frequencies of systolic BP elevations [mean difference (95% confidence interval, CI): 543.0 (487.2, I); p 0.0001] and diastolic BP elevations (205.8 (169.3, I); p 0.0001) were observed with PLMs than without PLMs. A peak in the frequency of PLM onset coincided with BP elevation onset. Conclusion Our methodology allowed the first evaluation of the total number of nocturnal PLM-associated BP elevations occurring in patients with RLS. Our data clearly indicate an interdependence between BP elevations and PLMs, and they have clinical relevance as BP variability is a potential cardiovascular risk factor.

Obstructive sleep apnea (OSA) is a clinically significant condition associated with an increase in cardiovascular risk, daytime sleepiness and in risk of accidents. Diagnosis usually relies on a detailed anamnesis and an ambulatory nocturnal polygraphy. Suspecting the presence of OSA or a persisting unclear daytime sleepiness in need of treatment further polysomnographic diagnosis should be performed in a specialized sleep center. Cardiorespiratory polysomnography is the diagnostic gold standard in differentiating sleep-related breathing and movement disorders.

Background The results of previous studies investigating the association between atrial fibrillation (AF) and central sleep apnea (CSA) in patients with left ventricular (LV) systolic dysfunction are contradictory. Methods We prospectively enrolled 267 patients in this cross-sectional study with LV ejection fractions ≤50%, who were screened for sleep disordered breathing using cardiorespiratory polysomnography after patients with predominantly obstructive sleep apnea or insufficient sleep studies had been excluded. Results AF at study entry was found in 70 of 267 patients (26%). CSA with an apnea/hypopnea index (AHI) ≥15/hour was present in 116 patients (43%) and 67 patients (25%) had severe CSA with an AHI > 30/hour. Univariate analysis revealed a significant association between AF and severe CSA, age, male gender, arterial hypertension, left atrial diameter, brain natriuretic peptide, chronic kidney disease, New York Heart Association class, digitalis, and the lack of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers. Multivariate analysis revealed a significant association between AF and severe CSA (odds ratio [OR]: 5.21; 95% confidence interval [CI]: 1.67–16.27, P = 0.01), age (OR: 1.22 per 5-year increase; 95% CI: 1.05–1.40, P = 0.01), left atrial diameter (OR 1.61 per 5-mm increase; 95% CI: 1.22–2.01, P < 0.01), and digitalis (OR: 2.7; 95% CI: 1.26–5.79, P = 0.01). Conclusions AF is associated with severe CSA but not with moderate CSA in addition to age, use of digitalis, and left atrial size in patients with LV systolic dysfunction. Future studies evaluating the potential benefit of adaptive servo-ventilation therapy to prevent AF or to decrease the AF burden in heart failure patients should therefore focus on patients with severe central sleep apnea.

Obstructive sleep apnea (OSA) is a clinically significant condition associated with an increase in cardiovascular risk, daytime sleepiness and in risk of accidents. Diagnosis usually relies on a detailed anamnesis and an ambulatory nocturnal polygraphy. Suspecting the presence of OSA or a persisting unclear daytime sleepiness in need of treatment further polysomnographic diagnosis should be performed in a specialized sleep center. Cardiorespiratory polysomnography is the diagnostic gold standard in differentiating sleep-related breathing and movement disorders.

Restorative functions of sleep are of special interest for sleep medicine. For the assessment of these restorative functions, various parameters are taken into account, among which sleep duration and sleep quality play the most important roles. Both terms are essential for sleep perception, expressing the subjective satisfaction of the individual with the time spent asleep. In recent decades, sleep medicine and sleep research have developed methods for the assessment of both objective and subjective dimensions of sleep. Among subjective methods, taking of the medical history focusing on the patient's sleep is important. Standardized and validated questionnaires play a supportive role. Objective methods are, for example, estimation of the sleep-wake cycle by means of actigraphy and polygraphy. Especially in multimorbid patients, polysomnography is still the gold standard method for diagnostics. An important approach during recent years is shifting from bothering overnight examinations into less disturbing procedures for patients that include performing ambulatory, outpatient examinations in the patients' home rather than inpatient surveillance within sleep centers.

The Sleep Disturbance Index (SDI) is a novel index based on polysomnography describing sleep quality in a single score. It was developed and tested with young subjects in the context of research on the effects of noise on sleep. In this study, it is applied in a clinical setting for the first time. A total of 79 patients with suspected sleep apnea received diagnostic polysomnography and the SDI was calculated for these patients. SDI scores in this clinical sample were higher than those of normal young sleepers. They were normally distributed and showed a rather close relationship (r = 0.47) to the Apnea-Hypopnea Indices as measures of disease severity. Patients with more breathing disorders tend to have a higher SDI indicating more impaired sleep. An explorative comparison of SDI scores of this clinical group with SDI scores obtained in noise exposition studies showed higher SDI scores for the patient group. The SDI seems a promising approach to describe sleep in a single score and facilitate comparisons of the effects of, e. g. environmental and medical factors affecting sleep.

Objective: This double-blind, placebo-controlled, interventional trial was conducted to investigate the effects of rotigotine patch on periodic limb movement (PLM)–associated nocturnal systolic blood pressure (SBP) elevations. Methods: Patients with moderate to severe restless legs syndrome (RLS) were randomized to rotigotine (optimal dose [1–3 mg/24 h]) or placebo. Continuous beat-to-beat blood pressure (BP) assessments were performed during polysomnography at baseline and at the end of 4-week maintenance. Primary outcome was change in number of PLM-associated SBP elevations (defined as slope of linear regression ≥2.5 mm Hg/beat-to-beat interval over 5 consecutive heartbeats [≥10 mm Hg]). Additional outcomes were total SBP elevations, PLM-associated and total diastolic BP (DBP) elevations, periodic limb movements index (PLMI), and PLM in sleep arousal index (PLMSAI). Results: Of 81 randomized patients, 66 (37 rotigotine, 29 placebo) were included in efficacy assessments. PLM-associated SBP elevations were significantly reduced with rotigotine vs placebo (least squares mean treatment difference [95% confidence interval (CI)] −160.34 [−213.23 to −107.45]; p < 0.0001). Rotigotine-treated patients also had greater reduction vs placebo in total SBP elevations (−161.13 [−264.47 to −57.79]; p = 0.0028), PLM-associated elevations (−88.45 [−126.12 to −50.78]; p < 0.0001), and total DBP elevations (−93.81 [−168.45 to −19.16]; p = 0.0146), PLMI (−32.77 [−44.73 to −20.80]; p < 0.0001), and PLMSAI (−7.10 [−11.93 to −2.26]; p = 0.0047). Adverse events included nausea (rotigotine 23%; placebo 8%), headache (18% each), nasopharyngitis (18%; 8%), and fatigue (13%; 15%). Conclusions: Further investigation is required to determine whether reductions in nocturnal BP elevations observed with rotigotine might modify cardiovascular risk. Classification of evidence: This study provides Class I evidence that for patients with moderate to severe RLS, rotigotine at optimal dose (1–3 mg/24 h) reduced PLM-associated nocturnal SBP elevations.

Objective: To assess the efficacy and safety of the dopamine agonist cabergoline in the treatment of patients with idiopathic restless legs syndrome (CATOR study). Methods: Patients with moderate to severe restless legs syndrome (RLS) were randomly assigned to cabergoline (single evening dose: 2 mg) or placebo and treated for 5 weeks in a double-blind, multicenter polysomnography (PSG) trial. The primary efficacy measures were the periodic leg movements during sleep arousal index (PLMS-AI) and sleep efficiency. These and further PSG variables were monitored by centrally evaluated PSG. Severity of RLS was assessed using the International RLS Study Group Severity Scale (IRLS), the RLS-6 scales, the Sleep Questionnaire Form A (SF-A; quality of sleep), and the Quality of Life for RLS questionnaire. Results: Forty-three patients were treated and 40 patients were evaluated with PSG (age 56 ± 10 years, 73% women). Cabergoline was superior to placebo in terms of the PLMS-AI (−17.7 ± 16.4 vs −4.5 ± 20.0 placebo; p = 0.0024), sleep efficiency (+6.2 ± 13.9% vs +3.3 ± 11.7%; p = 0.0443), PLMS index ( p = 0.0014), PLM index ( p = 0.0012), and total sleep time ( p = 0.0443). Improvements in IRLS total score (−23.7 ± 11.2 vs −7.9 ± 11.0 placebo; p = 0.0002), RLS-6 severity scales during the night ( p = 0.0010) and during the day ( p = 0.0018), Clinical Global Impressions severity item ( p = 0.0003), sleep quality ( p = 0.0180), SF-A sleep quality ( p = 0.0371), and QoL-RLS ( p = 0.0247) were larger in patients treated with cabergoline compared with the placebo group. Adverse events were only mild and well-known side effects of dopamine agonists. Conclusion: Single-evening cabergoline is an efficacious and well-tolerated short-term therapy for sensorimotor symptoms of restless legs syndrome and associated sleep disturbances.

The term ‘sleep attack’ is used in patients with Parkinson's disease (PD) to designate a sudden onset of sleep (SOS) without any prior sleepiness. Clinically, sleep attacks can be distinguished from unintended sleep episodes, i.e. SOS with prior sleepiness. This study aimed to assess the prevalence of SOS and to identify its predictors in patients with sleep-disordered breathing (SDB). A total of 114 consecutive patients with the clinical suspicion of obstructive sleep apnoea syndrome (OSAS) and a respiratory disturbance index (RDI) of >5/h were examined using a questionnaire and polysomnography (PSG). Altogether 57.7% reported SOS, with 5.2% of the total population describing exclusively sleep attacks. SOS was observed in both patients with obstructive sleep apnoea-hypopnoea (OSAH) or increased upper airway resistance (UAR). Increased scores on the Epworth Sleepiness Scale (ESS) were the best predictor of SOS. Logistic regression showed a possible association of SOS with a low PLMS index, while no definite effect was observed for other PSG parameters. Our data show that SDB is frequently associated with SOS. Future studies should address in more detail whether SDB patients with sleep attacks pose an increased accident risk.

Six patients with Parkinson's disease (PD) reporting unusually fast or sudden onset of sleep under the addition of dopamine agonists to a previous levodopa-containing therapy were examined using a sleep–wake diary, the Epworth sleepiness scale (ESS), polysomnography, multiple sleep latency tests (MSLT), a standardized vigilance test, and driving simulation. In all patients, ESS scores were increased and polysomnography showed disruption of the sleep pattern, a tendency towards poor sleep efficiency, and reduced proportions of slow- wave and rapid eye movement sleep. Pathological results in the MSLT or the vigilance test were obtained in five cases. For evaluation of driving performance, the standard deviation from the mean lane position during driving simulation was calculated. Three of five patients had clearly increased mean SDLP values. With respect to the measurement of daytime sleepiness (ESS, MSLT, vigilance test, and driving simulation), each patient had pathological results in at least two of these examinations. However, only a limited transfer of the routine vigilance assessment to driving performance was possible. In summary, this pilot study indicates that unusually fast or sudden onset of sleep in PD patients is a phenomenon of daytime sleepiness. © 2002 Movement Disorder Society.

The results of previous studies investigating the association between atrial fibrillation (AF) and central sleep apnea (CSA) in patients with left ventricular (LV) systolic dysfunction are contradictory.We prospectively enrolled 267 patients in this cross-sectional study with LV ejection fractions ≤50%, who were screened for sleep disordered breathing using cardiorespiratory polysomnography after patients with predominantly obstructive sleep apnea or insufficient sleep studies had been excluded.AF at study entry was found in 70 of 267 patients (26%). CSA with an apnea/hypopnea index (AHI) ≥15/hour was present in 116 patients (43%) and 67 patients (25%) had severe CSA with an AHI30/hour. Univariate analysis revealed a significant association between AF and severe CSA, age, male gender, arterial hypertension, left atrial diameter, brain natriuretic peptide, chronic kidney disease, New York Heart Association class, digitalis, and the lack of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers. Multivariate analysis revealed a significant association between AF and severe CSA (odds ratio [OR]: 5.21; 95% confidence interval [CI]: 1.67-16.27, P = 0.01), age (OR: 1.22 per 5-year increase; 95% CI: 1.05-1.40, P = 0.01), left atrial diameter (OR 1.61 per 5-mm increase; 95% CI: 1.22-2.01, P0.01), and digitalis (OR: 2.7; 95% CI: 1.26-5.79, P = 0.01).AF is associated with severe CSA but not with moderate CSA in addition to age, use of digitalis, and left atrial size in patients with LV systolic dysfunction. Future studies evaluating the potential benefit of adaptive servo-ventilation therapy to prevent AF or to decrease the AF burden in heart failure patients should therefore focus on patients with severe central sleep apnea.

We sought to determine prevalence and predictors of excessive daytime sleepiness in patients with severe obesity with a body mass index (BMI) > 35 kg/m2 and obstructive sleep apnea (OSA) with an apnea-hypopnea index > 15/h. The study population consisted of 245 obese OSA patients with a BMI > 35 kg/m2, who were retrospectively recruited from 3256 consecutive patients who underwent polysomnography at our sleep laboratory between 2006 and 2009. Baseline clinical characteristics and polysomnography results of these 245 patients were compared between patients with and without excessive daytime sleepiness, which was diagnosed in the presence of an Epworth Sleepiness Scale score (ESS) ≥ 11. A total of 123 of 245 study patients (50.2 %) had an ESS ≥ 11. Patients with an ESS ≥ 11 were younger and less often unemployed or retired compared with patients with an ESS

Sleep disturbances after general surgery have been described. In this study, we assessed rapid eye movement (REM) sleep in patients undergoing knee replacement surgery using a regional anesthetic technique.Ambulatory polysomnography (PSG) was performed on 3 nights: the night before surgery (PSG1), the first night after surgery (PSG2), and the fifth postoperative night (PSG3). Postoperative analgesia was maintained with peripheral nerve catheters for the first 3 days and with oral opioids thereafter. In addition, nonsteroidal antiinflammatory drugs were administered. Postoperative pain was monitored using a visual analog scale.PSG was performed in 12 patients, 6 men and 6 women, with a mean age of 61 (±12) years. REM sleep was reduced from PSG1 (median 16.4%) to PSG2 (median 6.3%; P = 0.02). The Hodges-Lehmann estimate for the median reduction is -7.8% (95% confidence interval -14.8% to -0.7%). During PSG3, significantly more REM sleep was detected (median 15.4%) compared with PSG2 (P = 0.01). The Hodges-Lehmann estimate for this median increase is 10.0% (95% confidence interval 1.7%-25.3%).Postoperative reduction of REM sleep also occurs after surgery and regional anesthesia.

Sleepiness whilst driving constitutes a road safety risk. Sleep-related breathing disorders are the most frequent medical cause of daytime sleepiness, and untreated patients with this condition have been shown to be at a higher risk of having accidents while driving. This study addressed the question of the extent to which treatment of sleep-disordered breathing by nasal continuous positive airway pressure (nCPAP) is related to changes in patient's accident risk. Seventy eight male patients requiring treatment of sleep-related breathing disorders with nCPAP were enrolled in the study. The protocol included a questionnaire dealing with alertness-related problems while driving, an 80 min vigilance test, and the Multiple Sleep Latency Test. These baseline evaluations were repeated after 1 year of treatment with nCPAP. Fifty nine patients completed the study. The accident rate was significantly decreased from 0.8 per 100,000 km (untreated) to 0.15 per 100,000 km with nCPAP treatment. Variables that were considered to be likely to increase accident risk (sleeping spells, fatigue, vigilance test reaction time, daytime sleep latency) also improved with treatment. We conclude that treatment of sleep-disordered breathing by nasal continuous positive airway pressure is related to reduction in patient motor vehicle accident rates, probably due to the reversal of excessive daytime sleepiness.

We performed a double-blind single-dose placebo/hypnotics crossover study randomized within groups to test the potential problems that a group of normal subjects, including subjects who snore, may face using hypnotic medications. Two benzodiazepine hypnotics--triazolam, 0.25 mg, and flunitrazepam, 2 mg tablets--were considered. Subjects were monitored with nocturnal polysomnography, including esophageal pressure (Pes) monitoring as a measure of respiratory efforts, and were given daytime performance tests. Results were analyzed for the total nocturnal sleep period and also by thirds of the night in consideration of the different half-lives of the studied drugs. Three specific respiratory variables were evaluated: mean breathing frequency for selected unit of time, "Delta Pes" (esophageal pressure at peak end-expiration minus Pes at peak end-inspiration) expressed in cm H2O, and the ratio of Delta Pes/Delta TI (inspiratory time), taken as an index of respiratory drive calculated for each respiratory cycle. There was no significant increase in either the respiratory disturbance index or the oxygen desaturation index (number of drops in arterial oxygen saturation of 4% or more per hour of sleep, as measured by pulse oximetry). There was a significant increase in mean breathing frequency with flunitrazepam compared with placebo, as well as a significantly larger percentage of time during sleep with Delta Pes above 10 cm H2O (taken as a cutoff point for normal respiratory effort) with both triazolam and flunitrazepam compared with placebo. These respiratory changes, even if significant, were minor but may become a liability in association with specific abnormalities.

Male patients with arterial hypertension and obstructive sleep-related breathing disorders (mean age 50 y, Body Mass Index (BMI) 32.4 kg m-2, Respiratory Disturbance Index (RDI) 47.2 and systolic/diastolic blood pressure (SBD/DBD) 162/103 mmHg) were examined before and after 8 days of treatment with the long-acting angiotensin-converting-enzyme (ACE) inhibitor cilazapril 2.5 mg vs. placebo in a double-blind design with parallel groups. Cardiorespiratory polysomnography was carried out at night; during daytime wakefulness patients submitted to examinations of physical and mental exertion. Cilazapril reduced the mean pressure during the entire examination period (day and night) by 9.55 (SD +/- 7.13) mmHg, compared to 4.57 (SD +/- 7.20) mmHg for placebo (P < 0.006), independently from systematic changes of heart rate (x = -3.3 and -3.5 bpm, respectively). During REM sleep, mean arterial pressure was significantly reduced by 8.63 (SD +/- 10.1) mmHg, compared to a reduction on placebo of 3.17 (SD 9.6) mmHg (P = 0.023). Under psychometric strain, the mean arterial pressure was reduced by 15.31 (SD +/- 8.7) mmHg with cilazapril; under placebo medication by 6.19 (SD +/- 7.3) mmHg (P < 0.0001). Heart rate was not significantly changed.

Complex sleep apnoea (CompSA) may be observed following continuous positive airway pressure (CPAP) treatment. In a prospective study, 675 obstructive sleep apnoea patients (mean age 55.9 yrs; 13.9% female) participated. Full-night polysomnography was performed at diagnosis, during the first night with stable CPAP and after 3 months of CPAP. 12.2% (82 out of 675 patients) had initial CompSA. 28 of those were lost to follow-up. Only 14 out of the remaining 54 patients continued to satisfy criteria for CompSA at follow-up. 16 out of 382 patients not initially diagnosed with CompSA exhibited novel CompSA after 3 months. 30 (6.9%) out of 436 patients had follow-up CompSA. Individuals with CompSA were 5 yrs older and 40% had coronary artery disease. At diagnosis, they had similar sleep quality but more central and mixed apnoeas. On the first CPAP night and at follow-up, sleep quality was impaired (more wakefulness after sleep onset) for patients with CompSA. Sleepiness was improved with CPAP, and was similar for patients with or without CompSA at diagnosis and follow-up. CompSA is not stable over time and is mainly observed in predisposed patients on nights with impaired sleep quality. It remains unclear to what extent sleep impairment is cause or effect of CompSA.

Study objectives Breath-to-breath variability is not purely random but is, instead, characterized by correlations on short- and long-term scales. Short-term correlations might reflect intact metabolic-control mechanisms. To investigate whether the higher variability of breathing during rapid eye movement (REM) compared to non-REM (NREM) sleep is of random or nonrandom nature--reflecting an altered respiratory control--short-term and long-term correlations of respiratory drive and timing were determined. Design A full-night polysomnogram with a pneumotachograph attached to a full-face mask was performed. For each breath during NREM and REM sleep, respiratory components were analyzed based on the quantitative airflow. Setting Data collection took place in the sleep laboratory. Participants Twenty-nine healthy subjects (age, 25.8 +/- 3.1 years). Measurements and results Long-term correlations are practically absent in respiratory timing and drive components during NREM sleep, whereas they are present during REM sleep. Short-term correlations are present in respiratory drive, tidal volume, and minute ventilation during both NREM and REM sleep. In all timing components, additional short-term correlations are absent. Conclusion We conclude that from NREM to REM sleep, short-term regulation of respiratory drive remains strongly metabolically controlled and clearly different from the short-term regulation of the rhythm-generating function. Regulation of respiratory timing and drive during REM sleep is characterized by additional long-term correlations. We speculate that this is the result of cortical influences during phasic REM sleep. Thus, the variability of breathing during REM sleep contains a nonrandom component, such that breathing components remain dependent upon each other even with large time lags between components.

CSF hypocretin-1 levels at 6 pm did not significantly differ between patients with restless legs syndrome (RLS) and control subjects as measured by direct radioimmunoassay and after acid extraction. The authors did not observe significant differences between early onset and late onset RLS. Hypocretin-1 levels did not correlate with RLS severity or polysomnographic measures. These results contrast with previous findings reporting significantly increased CSF hypocretin-1 in the late evening and mostly in early onset RLS.

Six patients with Parkinson's disease (PD) reporting unusually fast or sudden onset of sleep under the addition of dopamine agonists to a previous levodopa-containing therapy were examined using a sleep-wake diary, the Epworth sleepiness scale (ESS), polysomnography, multiple sleep latency tests (MSLT), a standardized vigilance test, and driving simulation. In all patients, ESS scores were increased and polysomnography showed disruption of the sleep pattern, a tendency towards poor sleep efficiency, and reduced proportions of slow- wave and rapid eye movement sleep. Pathological results in the MSLT or the vigilance test were obtained in five cases. For evaluation of driving performance, the standard deviation from the mean lane position during driving simulation was calculated. Three of five patients had clearly increased mean SDLP values. With respect to the measurement of daytime sleepiness (ESS, MSLT, vigilance test, and driving simulation), each patient had pathological results in at least two of these examinations. However, only a limited transfer of the routine vigilance assessment to driving performance was possible. In summary, this pilot study indicates that unusually fast or sudden onset of sleep in PD patients is a phenomenon of daytime sleepiness.

To develop improved methods for objective assessment of daytime vigilance. This is important in the diagnosis and therapy control of sleep disorders associated with excessive daytime sleepiness (EDS).Twenty-one patients with EDS due to obstructive sleep apnea were recorded during a daytime 90 min reaction time (RT) test in a monotonous situation. Two EEG, two EOG and a submental EMG channel were recorded simultaneously. The recordings were divided into short, stationary segments of variable length (0.5-2 s) and classified into 7 stages using our previously described system, which includes additional stages for drowsiness.The duration of RT was linearly correlated to the vigilance state (P0.05). The appearance of slow eye movements (SEM) was more consistently related to performance impairment than EEG changes.Our system can provide a better tracking of vigilance changes than the standardized sleep stage scoring. A 1-2 h test is useful in the assessment of the performance of a subject suffering from EDS. We found that SEMs indicate more sensitive and consistent EDS-related performance impairment than changes in EEG activity.