Continuous Positive Airway Pressure Titration Research Articles

Optimal Level of Continuous Positive Airway Pressure: Auto-Adjusting Titration versus Titration with a Predictive Equation

The aims of the present study were twofold. We sought to compare two methods of titrating the level of continuous positive airway pressure (CPAP) - auto-adjusting titration and titration using a predictive equation - with full-night manual titration used as the benchmark. We also investigated the reliability of the two methods in patients with obstructive sleep apnea syndrome (OSAS). Twenty consecutive adult patients with OSAS who had successful, full-night manual and auto-adjusting CPAP titration participated in this study. The titration pressure level was calculated with a previously developed predictive equation based on body mass index and apnea-hypopnea index. The mean titration pressure levels obtained with the manual, auto-adjusting, and predictive equation methods were 9.0 +/- 3.6, 9.4 +/- 3.0, and 8.1 +/- 1.6 cm H2O,respectively. There was a significant difference in the concordance within the range of +/- 2 cm H2O (p = 0.019) between both the auto-adjusting titration and the titration using the predictive equation compared to the full-night manual titration. However, there was no significant difference in the concordance within the range of +/- 1 cm H2O (p > 0.999). When compared to full-night manual titration as the standard method, auto-adjusting titration appears to be more reliable than using a predictive equation for determining the optimal CPAP level in patients with OSAS.

Comparison of manual versus automatic continuous positive airway pressure titration and the development of a predictive equation for therapeutic continuous positive airway pressure in Chinese patients with obstructive sleep apnoea

Whether the therapeutic nasal continuous positive airway pressure (CPAP) derived from manual titration is the same as derived from automatic titration is controversial. The purpose of this study was to compare the therapeutic pressure derived from manual titration with automatic titration. Fifty-one patients with obstructive sleep apnoea (OSA) (mean apnoea/hypopnoea index (AHI) = 50.6 ± 18.6 events/h) who were newly diagnosed after an overnight full polysomnography and who were willing to accept CPAP as a long-term treatment were recruited for the study. Manual titration during full polysomnography monitoring and unattended automatic titration with an automatic CPAP device (REMstar Auto) were performed. A separate cohort study of one hundred patients with OSA (AHI = 54.3 ± 18.9 events/h) was also performed by observing the efficacy of CPAP derived from manual titration. The treatment pressure derived from automatic titration (9.8 ± 2.2 cmH(2)O) was significantly higher than that derived from manual titration (7.3 ± 1.5 cmH(2)O; P < 0.001) in 51 patients. The cohort study of 100 patients showed that AHI was satisfactorily decreased after CPAP treatment using a pressure derived from manual titration (54.3 ± 18.9 events/h before treatment and 3.3 ± 1.7 events/h after treatment; P < 0.001). The results suggest that automatic titration pressure derived from REMstar Auto is usually higher than the pressure derived from manual titration.

Obstructive Sleep Apnea Syndrome : A Descriptive Review at King Hussein Medical Center

Results: About 82% of the overall study group have Obstructive Sleep Apnea Syndrome. The study group was 64 males and 36 females. Obstructive Sleep Apnea Syndrome was present in 82.8% of the male group and 80.6% of the female. In the age group ≤ 50 year, 76.9% of male patients and 57% of female patients had Obstructive Sleep Apnea Syndrome. In the age group above 50 years, 92% of males and 86.2% of female patients were diagnosed to have Obstructive Sleep Apnea Syndrome. About 86.6% of patients with body mass index more than 30 had Obstructive Sleep Apnea Syndrome, 30 patients underwent titration test in this study; 76.7% of patients had successful treatment with continuous positive airway pressure. Conclusions: Obstructive Sleep Apnea Syndrome is more common in men than women in patients less than 50 years, but it seems that obstructive sleep apnea is seen equally in both gender after the age of 50 years. Aging and obesity are the most important risk factors for the development of the syndrome. Based on our results, management with continuous positive airway pressure titration was successful in most of the patients.

Low Frequency Filtering of Nasal Pressure Channel Causes Loss of Flow Limitation

ABSTRACT.Study objectives: The objective of this clinical vignette is to explore whether changes in low filter settings for respiratory waveforms have a clinically significant effect on patient management of obstructive sleep apnea (OSA). Design: This is a case report. Methods: We collected data from a continuous positive airway pressure (CPAP) titration polysomnogram (PSG) performed in our university based sleep laboratory. We reviewed the flow signal using low frequency filter settings of 0.0. 0.1, 0.3, and 0.5 Hz. Results: We noted that a change in the low frequency filter for respiratory flow caused a change in the appearance of an otherwise flattened waveform indicating flow limitation to no longer appear flat. Conclusion: We noted that indiscriminate use of the low frequency filter for nasal pressure and flow estimate channels may lead to greater difficulty recognizing respiratory flow limitation.

CPAP therapy in patients with idiopathic pulmonary fibrosis and obstructive sleep apnea: does it offer a better quality of life and sleep?

The recent literature shows an increased incidence of obstructive sleep apnea (OSA) in patients with idiopathic pulmonary fibrosis (IPF). On the other hand, there are no published studies related to continuous positive airway pressure (CPAP) treatment in this patient group. Our aim was to assess the effect of CPAP on sleep and overall life quality parameters in IPF patients with OSA and to recognize and overcome possible difficulties in CPAP initiation and acceptance by these patients. Twelve patients (ten males and two females, age 67.1 ± 7.2years) with newly diagnosed IPF and moderate to severe OSA, confirmed by overnight attended polysomnography, were included. Therapy with CPAP was initiated after a formal in-lab CPAP titration study. The patients completed the Epworth Sleepiness Scale (ESS), the Pittsburgh Sleep Quality Index (PSQI), the Functional Outcomes in Sleep Questionnaire (FOSQ), the Fatigue Severity Scale (FSS), the SF-36 quality of life questionnaire, and the Beck Depression Inventory (BDI) at CPAP initiation and after 1, 3, and 6months of effective CPAP therapy. A statistically significant improvement was observed in the FOSQ at 1, 3, and 6months after CPAP initiation (baseline 12.9 ± 2.9 vs. 14.7 ± 2.6 vs. 15.8 ± 2.1 vs. 16.9 ± 1.9, respectively, p = 0.02). Improvement, although not statistically significant, was noted in ESS score (9.2 ± 5.6 vs. 7.6 ± 4.9 vs. 7.5 ± 5.3 vs. 7.7 ± 5.2, p = 0.84), PSQI (10.7 ± 4.4 vs. 10.1 ± 4.3 vs. 9.4 ± 4.7 vs. 8.6 ± 5.2, p = 0.66), FSS (39.5 ± 10.2 vs. 34.8 ± 8.5 vs. 33.6 ± 10.7 vs. 33.4 ± 10.9, p = 0.44), SF-36 (63.2 ± 13.9 vs. 68.9 ± 13.5 vs. 72.1 ± 12.9 vs. 74.4 ± 11.3, p = 0.27), and BDI (12.9 ± 5.5 vs. 10.7 ± 4.3 vs. 9.4 ± 4.8 vs. 9.6 ± 4.5, p = 0.40). Two patients had difficulty complying with CPAP for a variety of reasons (nocturnal cough, claustrophobia, insomnia) and stopped CPAP use after the first month, despite intense follow-up by the CPAP clinic staff. Heated humidification was added for all patients in order to improve the common complaint of disabling nocturnal cough. Effective CPAP treatment in IPF patients with OSA results in a significant improvement in daily living activities based on the FOSQ, namely an OSA-specific follow-up instrument. Improvement was also noted in other questionnaires assessing quality of life, though not to a statistically significant degree, probably because of the multifactorial influences of IPF on physical and mental health. The probability of poor CPAP compliance was high and could only be eliminated with intense follow-up by the CPAP clinic staff.

Continuous positive airway pressure titration in infants with severe upper airway obstruction or bronchopulmonary dysplasia

aIntroductionNoninvasive continuous positive airway pressure (CPAP) is recognized as an effective treatment for severe airway obstruction in young children. The aim of the present study was to compare a clinical setting with a physiological setting of noninvasive CPAP in infants with nocturnal alveolar hypoventilation due to severe upper airway obstruction (UAO) or bronchopulmonary dysplasia (BPD).MethodsThe breathing pattern and respiratory muscle output of all consecutive infants due to start CPAP in our noninvasive ventilation unit were retrospectively analysed. CPAP set on clinical noninvasive parameters (clinical CPAP) was compared to CPAP set on the normalization or the maximal reduction of the oesophageal pressure (Poes) and transdiaphragmatic pressure (Pdi) swings (physiological CPAP). Expiratory gastric pressure (Pgas) swing was measured.ResultsThe data of 12 infants (mean age 10 ± 8 mo) with UAO (n = 7) or BPD (n = 5) were gathered. The mean clinical CPAP (8 ± 2 cmH2O) was associated with a significant decrease in Poes and Pdi swings. Indeed, Poes swing decreased from 31 ± 15 cmH2O during spontaneous breathing to 21 ± 10 cmH2O during CPAP (P < 0.05). The mean physiological CPAP level was 2 ± 2 cmH2O higher than the mean clinical CPAP level and was associated with a significantly greater improvement in all indices of respiratory effort (Poes swing 11 ± 5 cm H2O; P < 0.05 compared to clinical CPAP). Expiratory abdominal activity was present during the clinical CPAP and decreased during physiological CPAP.ConclusionsA physiological setting of noninvasive CPAP, based on the recording of Poes and Pgas, is superior to a clinical setting, based on clinical noninvasive parameters. Expiratory abdominal activity was present during spontaneous breathing and decreased in the physiological CPAP setting.

Motivational Measurements Predict No Show Rates for Titration Studies and Use of Alternative Therapies

Motivational Measurements Predict No Show Rates for Titration Studies and Use of Alternative Therapies Background: Overall adherence in health care is suboptimal, including adherence to continuous positive airway pressure (CPAP) for obstructive sleep apnea (OSA). One of the leading strategies to improve patient acceptance and adherence to change is motivational interviewing (MI). We hypothesize that motivational measurements will predict patients’ show rate for CPAP titration studies and use of alternative therapies. Methods: Adult patients rated their perceived importance of CPAP therapy and their confidence of success with therapy on a 1-10 Likert-type scale prior to their diagnostic polysomnogram (PSG). Demographic data, referral clinic, body mass index (BMI), Epworth Sleepiness Scale (ESS), treatment, and apnea hypopnea index (AHI) were collected. We classified patients into either Group 1, defined by those who reported both high importance of CPAP and high confidence of success with therapy (scores of 8 or higher for both), or Group 2 as those that rated lower importance or confidence (score <8 on at least one measure). Statistical analysis utilized unpaired t-tests and Fisher’s exact tests with a significant p value of 0.05.

Clinical and polysomnographic characteristics and response to continuous positive airway pressure therapy in obstructive sleep apnea patients with nightmares

To assess the characteristics of obstructive sleep apnea (OSA) patients with nightmares and the effects of continuous positive airway pressure (CPAP) therapy on nightmares. Consecutive patients referred with a clinical suspicion of OSA underwent attended overnight sleep studies. OSA and nightmares were diagnosed according to the American Academy of Sleep Medicine (AASM) criteria, and CPAP titration was performed in accordance with the AASM guidelines. A follow-up visit was performed 3months later, and the patients with nightmares were divided into two groups: group 1 used CPAP with good compliance, whereas group 2 refused CPAP treatment and did not use other alternative treatments for OSA. The study included 99 patients who had been diagnosed with OSA with nightmares. Their mean age was 47.2±11.2years, and they had a mean apnea-hypopnea index (AHI) of 36.5±34.3/h. Also included were 124 patients with OSA without nightmares. The mean age of these patients was 45.4±13.9years, and they had a mean AHI of 40.2±35/h. The patients with nightmares had a significantly higher AHI during rapid eye movement sleep (REM) compared with the patients without nightmares (51.7±28.1 vs 39.8±31.9/h). Logistic regression analysis revealed that the REM-AHI and interrupted sleep at night were independent predictors of nightmares in the OSA patients. Nightmares disappeared in 91% of the patients who used CPAP compared with 36% of patients who refused to use CPAP (p<0.001). Nightmares in OSA patients are associated with a higher REM-AHI. CPAP therapy results in a significant improvement in nightmare occurrence.

Cervical Osteophytes

Uncertain etiology of cervical osteophytes, in particular emerging in geriatric population, is a rare skeletal system disease. Often, the cases are asymptomatic and may lead to symptoms such as dysphagia, cough, dyspnea, and dysphonia. We present a patient who had anterior osteophytes causing symptoms of severe obstructive sleep apnea (OSA), and literature on etiology of OSA has been reviewed. A 57-year-old male patient with complaints of snoring and cessation of breathing during sleep was referred to the ear nose throat clinic. Cervical radiograph and computed tomography showed the osteophytes in the anterior of the vertebral corpus at the level C1-2. In addition, bridging osteophyte was observed between C6 and C7 vertebrae. The patient's neck circumference was 41 cm, body mass index was 29 kg/m2, Epworth Sleepiness Scale score was 11, and apnea hypopnea index was 62. Surgery was recommended, but the patient refused. Continuous positive airway pressure titration was applied with 12.6 cm H2O pressure; apnea control was attained with an AHI of 2.7. One of the rare causes of OSA, a case of cervical vertebral osteophyte, was presented, and we would like to draw attention to the importance of ear nose throat examination in the diagnosis of OSA.

Humidification during CPAP titration: an unresolved issue

AbbreviationsAHI Apnea–hypopnea indexCPAP Continuous positive airway pressureHH Heated humidifierOSA Obstructive sleep apneaDear Editor,Thereisstillacontroversyovertheroleandpositiveeffectsofheated humidifier (HH) on nasopharyngeal symptoms andobjective measures during continuous positive airway pres-sure(CPAP)titration[1,2].WereadwithinterestthearticlebyYu et al. [3] who analyzed the effects of HH during CPAPtitration in subjects with and without nasopharyngeal symp-toms. The investigators randomly assigned 52 patients withobstructive sleep apnea (OSA) during CPAP titration underpolysomnographic monitoring into HH and non-HH groups.The authorsassessedsymptomatology (nasalcavity, pharynx,and nasopharynx) before and after CPAP titration, and evalu-ated leak, AHI reduction, and optimal CPAP pressure level inthe two groups. They concluded that HH does not improveany of the objective measures during CPAP titration and didnot recommend the use of HH during CPAP titration. Webelieve that the conclusion is overstated based on the pre-sented data. The results cannot be generalized to all OSApatients undergoing CPAP titration. The need for humidifica-tion during positive airway pressure therapy through a nonin-vasive route is influenced by several factors such as air leaks,interface, room temperature, temperature of inhaled gas, air-flow, and pressure used [4].External humidification will have no added benefits inpatients who can maintain adequate physiological levels ofhumidity. As the pressure needed to overcome the obstruc-tive respiratory events in the studied group was relativelylow, it seems that the studied subjects were able to maintainadequate airway humidity without HH. The conclusions ofthe study of Yu et al. [3] cannot be generalized to OSApatients who require high positive airway pressure to over-come airway obstruction. Another important issue to con-sider when assessing the need for humidification is thepresence of mouth breathing and mouth leaks. Mouthbreathing may generate unidirectional nasal air flow andresults in significant increase in nasal airway resistanceand hence mouth leaks [5]. The nasal mucosa has a consid-erable ability for heating and humidifying inspired air; how-ever, it can be overwhelmed at high flow rates with CPAPand when there is unidirectional flow caused by mouthleaks. The potential effects of mouth breathing were notevaluated in the paper of Yu et al. [3].Therefore, we think that the role of humidificationduring CPAP titration cannot be discarded. Humidifica-tion may be beneficial in selected OSA patients duringCPAP titration such as patients with mouth breathingand patients requiring high positive airway pressure toeliminate airway obstruction. Future studies should as-sess the role of humidification during CPAP titration inpatients with mouth breathing and patients requiringhigh positive airway pressure.

Author response to “Humidification during CPAP titration: an unresolved issue”

We read the letter from Antonio et al. They think humidification may be beneficial in selected obstructive sleep apnea patients during continuous positive airway pressure (CPAP) titration such as patients with mouth breathing and patients requiring high positive airway pressure to eliminate airway obstruction. The role of humidification during CPAP titration cannot be discarded. Our study is not to discard the role of humidification. Our results just showed that routine use of humidification during CPAP titration did not yield significant benefits regardless of initial nasal symptoms or diseases. Therefore, we emphasize that the routine humidification may be not necessary, but it does not mean that humidification is useless for specific patents. We hope the readers do not misunderstand this point. Antonio et al. point out a very important and interesting issue in this part. We agree that humidification may be beneficial in patients with mouth breathing and patients needing high CPAP pressure to maintain airway. But there are no clinical parameters that can early find out which patients are mouth breathers or those who required high CPAP pressure. Otherwise, there is no clear definition about mouth breathing and what level of pressure can be classified as high CPAP pressure. The severity of mouth breathing may be variable and which degree of mouth breathing will interrupt the normal humidity level is not known. In our points of view, the best way to evaluate this issue is to monitor mouth leak and CPAP flow together with humidification level in real time. Further study is needed to clarify this point, but there are some technical problems that should be overcome.

Unmasking of Periodic Limb Movements With the Resolution of Obstructive Sleep Apnea During Continuous Positive Airway Pressure Application

Periodic limb movements (PLMs) and obstructive sleep apnea (OSA) may present as overlapping conditions. This study investigated the occurrence of PLM during continuous positive airway pressure (CPAP) titration, with the hypothesis that the presence of PLM during CPAP represented "unmasking" of a coexisting sleep disorder. A total of 78 polysomnographic recordings in 39 OSA subjects with an hourly PLM index ≥5 during CPAP application were evaluated. Application of CPAP significantly improved sleep architecture without change in the PLM index when compared with baseline. The PLM indices and PLM arousal indices were linearly correlated during both nights (r = 0.553, P < 0.01; r = 0.548, P < 0.01, respectively). Eleven subjects with low PLM indices at baseline had greater changes in the PLM index as compared with the sample remainder (P = 0.004). Sixteen subjects with significantly lower PLM indices at baseline required optimal CPAP levels higher than the sample average of 8.2 cm H2O (P = 0.032). These subjects also showed significantly higher median apnea-hypopnea index (AHI) at baseline than the sample remainder (74.4 events per hour [range: 24.2-124.4 events per hour] vs. 22.7 events per hour [range: 8.6-77.4 events per hour], respectively, P < 0.001). These findings suggest that PLM seen during CPAP titration may be related to a concurrent sleep disorder because of "unmasking" in patients with treated OSA.

Continuous positive airway pressure delivered by oronasal mask may not be effective for obstructive sleep apnoea: Figure 1–

To the Editors: Continuous positive airway pressure (CPAP) is considered the gold standard treatment for patients with moderate to severe obstructive sleep apnoea (OSA). The treatment of OSA with CPAP was first conceptualised using a nasal-only interface because the pressure delivered through the nose would be transmitted to the back of the upper airway and would push the palate anteriorly [1]. Since the first description, the CPAP industry has developed a large number of different interfaces in order to improve patient comfort and adherence to treatment. Patients with OSA frequently present nasal obstruction and oronasal interfaces may be used to deliver CPAP. Nasal and oronasal masks are often used interchangeably and the choice of CPAP delivery interface for OSA therapy remains largely based on clinical experience. However, patients with OSA on oronasal mask are less adherent to CPAP for reasons that are not completely understood [2]. One recent randomised trial [3] and a preliminary report [4] suggest that the effectiveness of CPAP for treating OSA is variable when delivered by an oronasal interface. We describe a well-documented patient in whom CPAP was not effective when an oronasal mask was used due to the posterior displacement of the tongue. A 69-yr-old Japanese–Brazilian, body mass index 26.1 kg·m−2, presented to the outpatient sleep clinic complaining of typical symptoms suggestive of OSA, including loud snoring, witnessed apnoeas and excessive daytime sleepiness. The patient had a positive medical history of systemic hypertension and diabetes mellitus. A standard overnight polysomnography (Alice 5; Philips Respironics, Murrysville, PA, USA) confirmed severe OSA, with apnoea-hypopnoea index (AHI) 76 events per h and lowest oxygen saturation 58%. An in-laboratory manual CPAP titration study was performed with an oronasal mask because of reported oral breathing during sleep. CPAP was …

Effectiveness of Treatment Apnea-Hypopnea Index: A Mathematical Estimate of the True Apnea-Hypopnea Index in the Home Setting

To present a new measurement instrument, the Effectiveness of Treatment Apnea-Hypopnea Index (ET-AHI), which the authors developed to determine an estimate of the therapeutic control of obstructive sleep apnea (OSA). The authors retrospectively evaluated a cohort of patients with OSA who initially attempted to use continuous positive airway pressure (CPAP) therapy and subsequently underwent maxillomandibular advancement (MMA) surgery. The ET-AHI calculations were performed to estimate the level of CPAP adherence that would be necessary to achieve equivalence with the MMA surgical result and to reach effective AHIs of 5 and 15. The sample was composed of 37 adult patients (mean age, 44.2 ± 9.0 yr; 73% men) with moderate to severe OSA (baseline AHI, 56.3 ± 22.6). CPAP therapy was highly efficacious (CPAP titration AHI, 4.3 ± 5.9), but no patient could adequately adhere to treatment. MMA produced a significant decrease in OSA (AHI after MMA, 11.6 ± 7.4). The ET-AHI calculations predicted that an 86% adherence rate with CPAP would be necessary to achieve equivalence with MMA, whereas adherence rates of 99% and 79% may be required to achieve effective AHIs of 5 and 15, respectively. The ET-AHI has the potential to significantly affect the care of patients with OSA because it may provide the treating clinician with a valuable tool to estimate the control of OSA for any therapeutic intervention. How closely the ET-AHI predicts the true effective AHI in the home setting requires further validation.

REM behavior disorder in myotonic dystrophy type 2

A 63-year-old woman with myotonic dystrophy type 2[1][1] and obstructive sleep apnea by polysomnography, not on medications traditionally known to cause REM behavior disorder (RBD), had dream-enacting behavior (DEB). Overnight continuous positive airway pressure titration captured an episode of DEB

Feasibility of Continuous Positive Airway Pressure by Primary Care Paramedics

Introduction. Continuous positive airway pressure (CPAP) has been used effectively in the prehospital environment for a wide range of respiratory emergencies. The feasibility of CPAP when used by primary care paramedics (PCPs) has not been established. Objective. We sought to study the feasibility of prehospital CPAP when used by paramedics trained to the primary care paramedic (PCP) level compared with those trained to the advanced care paramedic (ACP) level. Our hypothesis was that the feasibility of CPAP use by paramedics trained to the PCP level is similar to that of paramedics trained to the ACP level. Methods. We conducted an observational study of 302 consecutive cases of CPAP use over one year beginning June 25, 2009. We defined compliant use as 100% adherence to the provincial CPAP medical directive. The criteria for compliance included specifics of patient presentation, vital signs, and appropriate documentation by the paramedic, as well as proper use, titration, and discontinuation of CPAP equipment according to protocol. Data were abstracted from ambulance call reports. Results. Using the criteria set out for compliant CPAP use, the highest level of compliance among the ACPs and the PCPs was 98.6% and 98.9%, respectively, for documenting indication for CPAP use. The lowest level of compliance among the ACPs was 84.4% for titration of CPAP during treatment, and the lowest level of compliance among the PCPs was 90% for adherence to criteria for CPAP application according to patients’ vital signs. Overall, the criteria for compliant use of CPAP were met for 76.8% (232/302) of the call reports examined. The rate of compliant use of CPAP was 75.9% (161/212) for ACP calls and 78.9% (71/90) for PCP calls. The difference between rates of compliant use for ACP calls versus PCP calls was not statistically significant (χ2 [1 df] = 0.31, p = 0.66). Conclusions. This study found no significant difference in the compliant use of prehospital CPAP between paramedics trained to the PCP level and those trained to the ACP level. This study suggests that CPAP use by PCP-level paramedics may be feasible. Further study is required to determine whether compliance translates to safe use of prehospital CPAP by PCP-level paramedics.

A Multisite Randomized Trial of Portable Sleep Studies and Positive Airway Pressure Autotitration Versus Laboratory-Based Polysomnography for the Diagnosis and Treatment of Obstructive Sleep Apnea: The HomePAP Study

To test the utility of an integrated clinical pathway for obstructive sleep apnea (OSA) diagnosis and continuous positive airway pressure (CPAP) treatment using portable monitoring devices. Randomized, open-label, parallel group, unblinded, multicenter clinical trial comparing home-based, unattended portable monitoring for diagnosis and autotitrating CPAP (autoPAP) compared with in-laboratory polysomnography (PSG) and CPAP titration. Seven American Academy of Sleep Medicine (AASM) accredited sleep centers. Consecutive new referrals, age 18 yr or older with high probability of moderate to severe OSA (apnea-hypopnea index [AHI] ≥ 15) identified by clinical algorithm and Epworth Sleepiness Scale (ESS) score ≥ 12. Home-based level 3 testing followed by 1 wk of autoPAP with a fixed pressure CPAP prescription based on the 90% pressure from autotitration of PAP therapy (autoPAP) device (HOME) compared with attended, in-laboratory studies (LAB). CPAP acceptance, time to treatment, adherence at 1 and 3 mo; changes in ESS, and functional outcomes. Of 373 participants, approximately one-half in each study arm remained eligible (AHI ≥ 15) to continue in the study. At 3 mo, PAP usage (nightly time at pressure) was 1 hr greater: 4.7 ± 2.1 hr (HOME) compared with 3.7 ± 2.4 hr (LAB). Adherence (percentage of night used ≥ 4 hr) was 12.6% higher: 62.8 ± 29.2% compared with 49.4 ± 36.1% in the HOME versus LAB. Acceptance of PAP therapy, titration pressures, effective titrations, time to treatment, and ESS score change did not differ between arms. A home-based strategy for diagnosis and treatment compared with in-laboratory PSG was not inferior in terms of acceptance, adherence, time to treatment, and functional improvements. http://www.ClinicalTrials.gov; Identifier: NCT: 00642486.

Determinants of continuous positive airway pressure adherence in a sleep clinic cohort of South Florida Hispanic veterans

There are little existing data on continuous positive airway pressure (CPAP) adherence in US Hispanic veterans with obstructive sleep apnea (OSA). Our aim was to describe determinants of 1-month adherence in a sleep clinic cohort of South Florida Hispanic veterans. Hispanic veterans referred to the Miami VA sleep clinic were recruited and completed questionnaires about sleep apnea risk, sleep quality, insomnia symptoms, sleepiness, depression/anxiety, acculturation, personality traits, and cognitions about OSA and CPAP. Individuals at risk for OSA were scheduled for baseline polysomnography (PSG), followed by in-lab CPAP titration or a trial of auto-CPAP. Participants with OSA accepting CPAP therapy were asked to return after 7 and 30days of treatment for adherence verification and to repeat questionnaires. One hundred twenty-four participants (94% men) were enrolled with 114 completing overnight PSG. Eighty-six out of 95 participants (91%) with sleep apnea syndrome or moderate to severe OSA accepted CPAP treatment. Fifty-nine participants completed both follow-up visits with a mean CPAP use at 30days of 3.6 ± 2.0h. The only independent predictor of 7-day mean daily CPAP use was the baseline Insomnia Severity Index while the best predictor of 30-day mean daily CPAP use was the 7-day mean daily use. Our study suggests that South Florida Hispanic veterans with OSA evaluated in a sleep clinic show poor CPAP adherence. Insomnia and poor early use predicted poor adherence overall. Larger prospective studies with other race-ethnic groups are needed to determine the role of ethnicity and race in CPAP adherence among US veterans with OSA.

Change in frequency of periodic limb movements during sleep with usage of continuous positive airway pressure in obstructive sleep apnea syndrome

Periodic limb movements during sleep (PLMS) sometimes newly appear on the night of continuous positive airway pressure (CPAP) titration in patients with obstructive sleep apnea syndrome (OSAS). To ascertain the incidence and causative factors of this phenomenon, we investigated differences in its prevalence and the factors associated with newly appeared and persistent PLMS on CPAP titration night. We retrospectively analyzed polysomnographic data of 997 consecutive OSAS outpatients who had undergone overnight CPAP titration. On the basis of changes in periodic limb movements index (PLMI) values (cut off level≥15/h) from baseline polysomnography (BPSG) to CPAP titration PSG, patients were assigned to one of four groups: persistent, CPAP-emergent, CPAP-disappeared, and non-PLMS. The rate of patients was 6.7% in the persistent group, 8.0% in the CPAP-emergent group, 4.0% in the CPAP-disappearance group, and 81.2% in the non-PLMS group. Multivariate logistic regression analysis revealed that a higher apnea–hypopnea index (AHI) on BPSG and ≥47years of age appeared to be associated with the CPAP-emergent group. The results suggest that elderly patients with higher AHI at BPSG may present with CPAP-emergent PLMS.

Rapid eye movement and slow‐wave sleep rebound after one night of continuous positive airway pressure for obstructive sleep apnoea

Rebound of slow-wave sleep (SWS) and rapid eye movement (REM) sleep is observed in patients who are on continuous positive airway pressure (CPAP) therapy for obstructive sleep apnoea (OSA); but, neither have been objectively defined. The pressure titration study often represents the first recovery sleep period for patients with OSA. Our aim was to objectively define and identify predictors of SWS and REM sleep rebound following CPAP titration. Paired diagnostic polysomnography and pressure titration studies from 335 patients were reviewed. The mean apnoea-hypopnoea index was 40.7 ± 26.1, and minimum oxygen saturation was 76 ± 14.4%. Comparing eight incremental thresholds, a rebound of 20% in REM sleep and a 40% increase in SWS allowed the best separation of prediction models. A 20% rebound in REM sleep was predicted by REM sleep %, non-REM arousal index (ArI) and total sleep time during diagnostic polysomnography, and male gender (R(2) = 35.3%). A 40% rebound in SWS was predicted by SWS %, total ArI and REM sleep % during diagnostic polysomnography, and body mass index (R(2) = 45.4%). A 40% rebound in SWS, but only a 20% rebound in REM sleep on the pressure titration study, is predicted by abnormal sleep architecture and sleep fragmentation prior to the commencement of treatment.