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The Effect of OSA Therapy on Glucose Metabolism: It's All about CPAP Adherence!

The Effect of OSA Therapy on Glucose Metabolism: It's All about CPAP Adherence!

Correlates of Pediatric CPAP Adherence.

Obstructive sleep apnea (OSA) is a common pediatric condition characterized by recurrent partial or complete cessation of airflow during sleep, typically due to inadequate upper airway patency. Continuous positive airway pressure (CPAP) is a therapeutic option that reduces morbidity. Despite efforts to promote use, CPAP adherence is poor in both pediatric and adult populations. We sought to determine whether demographics, insurance status, OSA severity, therapeutic pressure, or comorbid conditions were associated with pediatric CPAP adherence. A retrospective review of adherence download data was performed on all pediatric patients with initiation or adjustment of CPAP treatment over a one-year period with documented in-laboratory CPAP titration. Patients were grouped as CPAP adherent or non-adherent, where adherence was defined as > 70% nightly use and average usage ≥ 4 hours per night. Differences between the groups were analyzed by χ(2) test. Overall, nearly half of participants were CPAP adherent (49%, 69/140). Of the demographic data collected (age, ethnicity, sex, insurance status), only female sex was associated with better adherence (60.9% vs 39.5% of males adherent; odds ratio [OR] = 2.41, 95%CI = 1.20-4.85; p = 0.01). Severity of OSA (diagnostic apnea-hypopnea index [AHI] and degree of hypoxemia), therapeutic pressure, and residual AHI did not impact CPAP adherence (p > 0.05). Patients with developmental delay (DD) were more likely to be adherent with CPAP than those without a DD diagnosis (OR = 2.55, 95%CI = 1.27-5.13; p = 0.007). Female patients with trisomy 21 tended to be more adherent, but this did not reach significance or account for the overall increased adherence associated with female sex. Our study demonstrates that adherence to CPAP therapy is poor but suggests that female sex and developmental delay are associated with better adherence. These findings support efforts to understand the pathophysiology of and to develop adherence-promoting and alternative interventions for pediatric OSA.

Polygraphic respiratory events during sleep in children treated with home continuous positive airway pressure: description and clinical consequences

ObjectiveData are scarce on respiratory events during sleep for children treated at home with continuous positive airway pressure (CPAP). The present study aimed to characterize the respiratory events with CPAP during sleep and to analyze their clinical consequences. Patients/MethodsConsecutive polygraphies (PG) performed on stable children treated with CPAP were analyzed and scored using SomnoNIV Group definitions. For every respiratory event, the presence of a 3% oxygen desaturation and/or an autonomic arousal was systematically searched. Nocturnal gas exchange was assessed using summary data of oximetry and transcutaneous carbon dioxide pressure recordings. ResultsTwenty-nine consecutive polygraphies, performed on 26 children (mean age 7.8 ± 6.2 years, mean CPAP use 10.6 ± 14.4 months), were analyzed. The index of total respiratory events was low (median value 1.4/h, range 0–34). The mean number of different types of respiratory events per PG was 2 ± 1 (range 0–4), with always a predominant event. Partial or total upper airway obstruction without a decrease in ventilatory drive was the most frequent event and was the most frequently associated with an oxygen desaturation (in 30% of the events) and an autonomic arousal (in 55% of the events). Weak correlations were observed between nocturnal oximetry and PG results. ConclusionsThe index of respiratory events during CPAP treatment for stable children is low. As these events may be associated with an oxygen desaturation or an autonomic arousal, and as nocturnal gas exchange cannot predict PG results, a systematic sleep study seems justified for the routine follow-up of children treated with CPAP.

Financial incentive of home continuous positive airway pressure machine use in the inpatient hospital setting

Obstructive sleep apnea (OSA) is increasingly recognized as a significant factor in perioperative and inpatient health. Because of this, hospitalized OSA patients are encouraged to utilize continuous positive airway pressure (CPAP) therapy while inpatients. We investigated the cost difference of patient-owned versus hospital-provided CPAP machine use by admitted adult patients with OSA. Prospective cohort study at a tertiary academic center. All new-patient admissions >18 years of age who were prescribed CPAP while inpatients over a 2-month period were included. Demographic information was collected, and cost analysis was performed. CPAP was used for 162 (1.2%) admissions. Mean patient age was 59 ± 13 years; the majority were white (56.8%) and male (64.2%). Average CPAP utilization was 5.3 ± 5.5 nights. The differential cost per day for patients using hospital-provided CPAP was $416.10 more than for patients using home CPAP machines. This cost included direct costs of an extended respiratory therapy (RT) initial visit, machine rental fee ($27.50), and additional RT evaluation time (mean, 85-145 relative value units). The base initial visit was the same for all patients. Over the 2-month study period, the total cost difference in charges was $195,912; this extrapolates to $1,175,471 yearly. This is the first study to characterize the magnitude of cost savings from utilization of home versus hospital-provided CPAP machines in patients requiring inpatient CPAP machine use. The use of patient-owned CPAP machines may reflect an opportunity to provide cheaper care while maintaining high patient safety and quality care. The actual economic impact to an individual hospital would vary based on the insurance payer mix.

Stage-matched intervention for adherence to CPAP in patients with obstructive sleep apnea: a randomized controlled trial

The objective of the study was to evaluate the effectiveness of stage-matched intervention on adherence to continuous positive airway pressure (CPAP) in patients with obstructive sleep apnea syndrome. One hundred and ten Chinese patients with newly diagnosed obstructive sleep apnea syndrome were enrolled in this study. They were randomly assigned into stage-matched care (SMC) and standard care (SC) groups (55 patients in each group). Patients in the SMC group received stage-matched intervention at different stages of behavior changes, and the SC group received only routine care. The intervention was based on the health action process approach theory and included risk perception, outcome expectancy, and self-efficacy. Questionnaires included the Self-Efficacy Measure for Sleep Apnea, the Epworth Sleepiness Scale (ESS), and the Pittsburgh Sleep Quality Index (PSQI). Data were collected at baseline and 1 and 3 months after home CPAP treatment, and hours of CPAP usage was also recorded at 1 and 3 months of follow-up. At 1 month, CPAP usage was 5.59 ± 0.56 h/night (mean ± SD) vs 5.28 ± 0.67 h/night in the SMC and SC groups, respectively (p = 0.016). At 3 months, CPAP usage was 5.65 ± 0.50 vs 5.26 ± 0.82 h/night in the SMC and SC groups, respectively (p = 0.006). Repeated ANOVA analysis demonstrated that risk perception, outcome expectancy, and self-efficacy in the SMC group were significantly higher than those of the SC group (p < 0.05). Moreover, the time × group interaction was significant for outcome expectancy and self-efficacy, indicating that the groups differed significantly in changes in outcome expectancy and self-efficacy over the three time points. There was a significant difference between the SMC and SC groups in terms of improvement in ESS (p < 0.001) and PSQI (p = 0.013) after 3 months of CPAP treatment. Stage-matched intervention could not only facilitate intention formation and enhance treatment self-efficacy but significantly improve CPAP adherence in OSA patients for the 3-month treatment.

Influence of Marital Status and Employment Status on Long-Term Adherence with Continuous Positive Airway Pressure in Sleep Apnea Patients

BackgroundLong-term adherence is a major issue in patients receiving home continuous positive airway pressure (CPAP) therapy for obstructive sleep apnea-hypopnea syndrome (OSAHS). In a multicenter prospective cohort (the Institut de Recherche en Santé Respiratoire des Pays de la Loire [IRSR] sleep cohort) of consecutive OSAHS patients in whom CPAP had been prescribed for at least 90 days, we studied the impact on long-term treatment adherence of socioeconomic factors, patients and disease characteristics prior to CPAP initiation.Methods and Principal FindingsAmong 1,141 patients in whom CPAP had been prescribed for an average of 504±251 days (range: 91 to 1035), 674 (59%) were adherent with a mean daily use of CPAP≥4 h (mean: 6.42±1.35 h). Stepwise regression analysis identified 4 independent factors of CPAP adherence including apnea-hypopnea index (AHI) (OR: 1.549, 95%CI 1.163 to 2.062 for AHI≥30 vs. AHI<30; p = 0.003), body mass index (BMI) (OR: 1.786, 95%CI 1.131 to 2.822 for BMI≥25 and <30 kg/m2, p = 0.01; OR: 1.768, 95%CI 1.145–2.731 for BMI≥30 kg/m2, p = 0.01 vs. BMI<25 kg/m2), employment status (OR: 1.414, 95%CI 1.097–1.821 for retired vs. employed; p = 0.007) and marital status (OR: 1.482, 95%CI 1.088–2.019 for married or living as a couple vs. living alone; p = 0.01). Age, gender, Epworth sleepiness scale, depressive syndrome, associated cardiovascular morbidities, educational attainment and occupation category did not influence CPAP adherence.ConclusionsMarital status and employment status are independent factors of CPAP adherence in addition to BMI and disease severity. Patients living alone and/or working patients are at greater risk of non-adherence, whereas adherence is higher in married and retired patients. These findings suggest that the social context of daily life should be taken into account in risk screening for CPAP non-adherence. Future interventional studies targeting at-risk patients should be designed to address social motivating factors and work-related barriers to CPAP adherence.

Telemetric CPAP titration at home in patients with sleep apnea–hypopnea syndrome

Background Home continuous positive airway pressure (CPAP) titration with automatic devices is not possible in a non-negligible percentage of patients with sleep apnea–hypopnea syndrome (SAHS). Objectives To test the feasibility of a novel telemetric system for home CPAP titration. Methods One-night home CPAP titration was carried out on 20 SAHS patients (56 ± 3 years; BMI = 35 ± 2 kg/m 2). A telemetric unit, based on the conventional GPRS mobile phone network and connected to a commercial CPAP device, allowed the hospital technician to monitor flow, pressure and air leaks by remote control and titrate CPAP (elimination of apneas, hypopneas, flow limitation and snoring) in real time. After 1 week, a full hospital polysomnography was performed while the patient was subjected to the value of CPAP that was previously titrated at home via telemetry. Results The home-titrated CPAP systematically improved patients’ breathing: the apnea–hypopnea index and percentage of sleep time with arterial oxygen saturation below 90% were reduced from 58.1 ± 5.1 to 3.8 ± 0.6 events/h and from 19.8 ± 1.1% to 4.4 ± 0.7%, respectively. This CPAP value (9.15 ± 0.47 cmH 2O) was virtually the same as the pressure that optimized breathing during hospital polysomnography (9.20 ± 0.41 cmH 2O; mean difference: 0.02 cmH 2O, limits of agreement: ± 1.00 cmH 2O). Conclusions This pilot study shows that a simple telemetric system, requiring neither a special telemedicine network nor any infrastructure in the patient’s home, made it possible to perform effective remote CPAP titration on SAHS patients.

The Impact of Educational Message Framing on Adherence to Continuous Positive Airway Pressure Therapy

Although of proven health benefit to persons with obstructive sleep apnea (OSA), adherence to continuous positive airway pressure (CPAP) therapy is suboptimal, with patterns of use that are established early and that are not easily altered after the initial experience. In a randomized controlled trial, 70 participants with OSA and cardiovascular disease were assigned to receive either positively or negatively framed education about CPAP. Objective adherence was measured following 30 days of home CPAP therapy. Daytime sleepiness, dispositional optimism, self-efficacy, and depression were also evaluated at baseline and after 30 days. CPAP use was greater in the group receiving negative message framing (p = .015).

Treatment of Obstructive Sleep Apnea Improves Cardiometabolic Function in Young Obese Women with Polycystic Ovary Syndrome

Women with polycystic ovary syndrome (PCOS) are insulin resistant and have a high risk of early-onset diabetes and cardiovascular disease. Obstructive sleep apnea (OSA) has adverse cardiometabolic consequences and is highly prevalent in women with PCOS. We sought to determine whether continuous positive airway pressure (CPAP) treatment of OSA has beneficial effects on cardiometabolic function in PCOS. Laboratory polysomnography and cardiometabolic measurements including insulin sensitivity and secretion (iv glucose tolerance test); 24-h profiles of plasma catecholamines, cortisol, and leptin; and daytime profiles of blood pressure and cardiac autonomic activity (heart rate variability) were obtained at baseline and again after 8 wk of home CPAP treatment with daily usage monitoring. CPAP treatment modestly improved insulin sensitivity after controlling for body mass index (P = 0.013). The change in insulin sensitivity correlated positively with CPAP use (adjusted P = 0.027) and negatively with body mass index (adjusted P = 0.003). Daytime and nighttime norepinephrine levels were decreased after CPAP (P = 0.002), and the reductions were greater with increased CPAP use (P = 0.03). Epinephrine, cortisol, and leptin levels were not changed significantly. Daytime diastolic blood pressure decreased by an average of 2.3 mm Hg after CPAP (P = 0.035). Cardiac sympathovagal balance was 44% lower (P = 0.007) after CPAP, reflecting a shift toward lower sympathetic activity. In young obese women with PCOS, successful treatment of OSA improves insulin sensitivity, decreases sympathetic output, and reduces diastolic blood pressure. The magnitude of these beneficial effects is modulated by the hours of CPAP use and the degree of obesity.

Postoperative complications in patients with obstructive sleep apnea: a retrospective matched cohort study

Obstructive sleep apnea (OSA) is presumed to be a risk factor for postoperative morbidity and mortality, but the current evidence is incomplete. This retrospective matched cohort study tested the hypothesis that OSA is a risk factor for the development of postoperative complications. Hospital ethics approval was obtained for the conduct of this study. The patients who were selected for the study were >18 yr of age, diagnosed preoperatively with OSA, and scheduled to undergo elective surgery. A cohort of surgical patients without OSA was used as a comparator group based on a one-to-one match. Matching criteria included gender, age difference <5 yr, type of surgery, and a <5 yr difference between two surgery dates. Summary data are presented and conditional logistic regression was used to identify risk factors for postoperative complications. The 240 pairs of study subjects aged 57 +/- 13 yr included 184 (77%) males and 56 (23%) females. The OSA patients had a higher mean body mass index relative to their non-OSA counterparts (35 +/- 9 vs 28 +/- 6 kg . m-2, respectively) and a higher frequency of co-morbidities, including hypertension (48% vs 36%, respectively) and obesity (61% vs 23%, respectively). Also, the incidence of postoperative complications in the OSA patients was significantly greater (44% OSA group vs 28% non-OSA group; P < 0.05). The most commonly observed between-group difference was oxygen desaturation < 90% (17% OSA group vs 8% non-OSA group). The OSA patients who did not use home continuous positive airway pressure (CPAP) devices prior to surgery but required the use of a CPAP device after surgery had the highest rate of complications. Conditional logistic regression was used to diagnose OSA and pre-existing stroke as significant risk factors for developing postoperative complications. The hazard ratio for OSA was 2.0 (1.25-3.19). Patients with diagnosed OSA have an increased incidence of postoperative complications, the most frequent being oxygen desaturation.

Excessive daytime sleepiness in obstructive sleep apnea patients after home CPAP treatment: A long-term outcome study

Previous studies have been inconclusive about the improvement in excessive daytime sleepiness (EDS) after continuous positive airway pressure (CPAP) treatment. One hundred and thirty-one obstructive sleep apnea patients, who were on regular home CPAP treatment, were investigated with an overnight polysomnography and daytime multiple sleep latency test (MSLT). Their Epworth Sleepiness Scale (ESS) scores and mean sleep latencies (MSL) before and after treatment were compared. With a mean duration of CPAP treatment for 3.4 ± 2.4 years, improvement in both ESS (12.8 to 9.95) and MSLT (7.32 to 8.92 min) were found (P < 0.001). Residual EDS was found in 38.5% (20 out of 52) and 66.2% (51 out of 77) of subjects, measured by ESS (≥14) and MSL (≤8 min), respectively. Higher body mass index was found in those subjects with persistently shortened post-CPAP MSL of ≤8 min. Our findings suggested that EDS was a reversible symptom in some but not all OSAS patients. Whilst residual EDS could partly be accounted for by underlying obesity, the persistence of a shortened MSLT and sleep-onset REM period could be the result of underlying genetic factors and/or scarring effect due to hypoxic related neuronal damages.

Carbon Dioxide–Induced Narcosis due to Dry Ice Exposure in a Patient With Sleep Apnea

Letters3 March 2009Carbon Dioxide–Induced Narcosis due to Dry Ice Exposure in a Patient With Sleep ApneaJerrold B. Leikin, MD, Joseph F. Mitton, MD, and Thomas Freedom, MDJerrold B. Leikin, MDFrom Glenbrook Hospital, Glenview, IL 60026.Search for more papers by this author, Joseph F. Mitton, MDFrom Glenbrook Hospital, Glenview, IL 60026.Search for more papers by this author, and Thomas Freedom, MDFrom Glenbrook Hospital, Glenview, IL 60026.Search for more papers by this authorAuthor, Article, and Disclosure Informationhttps://doi.org/10.7326/0003-4819-150-5-200903030-00024 SectionsAboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinkedInRedditEmail Background: Dry ice is solid carbon dioxide. In enclosed spaces, evaporated carbon dioxide can displace oxygen to produce asphyxia.Objective: To report a case of carbon dioxide–induced asphyxia after exposure to 500 lb of dry ice in an enclosed minivan.Case Report: A 70-year-old, obese, nonsmoking male with a history of type 2 diabetes mellitus, hypertension, and obstructive sleep apnea for 3 years (treated with home continuous positive airway pressure) presented to an emergency department after being found unconscious in his minivan. He was revived with oxygen. The patient said that before losing consciousness he was “hyperventilating” but could not ...

Use of critical care resources after laparoscopic gastric bypass: effect on respiratory complications

Background Before 2005, all subjects undergoing laparoscopic gastric bypass with a body mass index >50 kg/m 2, age >40 years, and documented obstructive sleep apnea (OSA) were admitted to the intensive care unit (ICU) in our institution. Starting in January 2005, only patients with a body mass index >60 kg/m 2 and severe OSA were admitted. This study assessed the incidence of respiratory complications in patients undergoing laparoscopic gastric bypass before and after implementation of the new ICU admission criteria. Methods The records of the laparoscopic gastric bypass patients who had undergone laparoscopic gastric bypass from January 2004 to December 2005 were reviewed regarding demographic data (age, sex, body mass index, American Society of Anesthesiologists classification); OSA; use of home continuous positive airway pressure; length of stay in postanesthesia care unit, ICU, and hospital; postoperative ventilation and hypoxemia (oxygen saturation <90%), and unplanned ICU admission. Results A total of 250 charts were analyzed (122 from 2004 and 128 from 2005). The demographic data were comparable between the 2 groups. Although OSA was more frequent in the 2004 than in the 2005 cohort ( P = .02), the incidence of OSA requiring home continuous positive airway pressure was comparable ( P = .47). The length of hospital stay was greater in 2004 than in 2005 ( P = .003). More patients were admitted to the ICU in 2004 ( P <.001). All unplanned ICU admissions were because of surgical anastomotic/staple line leaks (7 patients in 2004 versus 0 in 2005; P = .006). Overall, the incidence of postoperative respiratory complications was low (6% in 2004 and 4% in 2005) and comparable in both groups. Conclusion Limiting ICU admission after laparoscopic gastric bypass to patients with a body mass index >60 kg/m 2 and severe OSA did not increase the overall incidence of postoperative respiratory complications or hospital stay.

Sleeping Together: A Pilot Study of the Effects of Shared Sleeping on Adherence to CPAP Treatment in Obstructive Sleep Apnea

To examine the sleep of married couples, recorded together in the laboratory before and after the husband is treated with continuous positive airway pressure (CPAP) to control his obstructive sleep apnea (OSA). The purpose was to investigate how these data relate to shared sleeping when he is on CPAP and his adherence to this treatment. Following a split-night diagnosis of OSA with CPAP titration, 10 married men slept for 2 additional nights with their non-apneic wife while both were recorded. The first night included a standard baseline 12-channel clinical polysomnogram without treatment. Following 2 weeks of home CPAP, the couple returned for a second polysomnography night with the husband on CPAP. Both partners completed Epworth Sleepiness Scales and Sleep Apnea Quality of Life Interviews each lab night. During the intervening 2 weeks, sleep logs were completed daily noting if CPAP was used, the presence of snoring, and where and how well they slept. Adherence data from machine downloads were obtained after an average of 4.6 months. The husbands' baseline sleep differed significantly from their wives on 6 of 7 sleep variables related to OSA and on Epworth Sleepiness Scale scores. Their sleep did not differ the second night, except for his lower percentage of slow wave sleep. Adherence to CPAP was unrelated to OSA severity but positively related to the number of nights the couple slept together during the 2 weeks of home CPAP. The frequency of sleeping together was negatively related to the wives' arousal frequency on laboratory nights. Although CPAP controls a husband's sleep-related OSA symptoms, his treatment adherence is strongly related to his wife sharing the bed. Addressing the wife's sensitivity to arousals when bed sharing may improve the husband's treatment adherence.

Comparison of CPAP Titration at Home or the Sleep Laboratory in the Sleep Apnea Hypopnea Syndrome

Continuous positive airway pressure (CPAP) for the treatment of obstructive sleep apnea hypopnea syndrome (OSAHS) is conventionally started after in-laboratory overnight titration. This use of sleep laboratory space is both costly and limits access for diagnostic studies. This study aimed to evaluate whether automated CPAP titration in the home produced patient outcomes equal to those following laboratory-based automated CPAP titration. The main outcomes were Epworth Sleepiness Scale score, objective daytime sleepiness (Oxford SLEep Resistance test or OSLER test), and CPAP use; we also performed quality-of-life questionnaires: Functional Outcomes of Sleep Questionnaire and SF-36. Prospective, randomized, single-blind, parallel-group, controlled trial Regional sleep center and patients' homes. Two hundred CPAP-naïve patients with OSAHS requiring CPAP treatment. One hundred patients were randomly assigned to a standard 1-night in-hospital CPAP titration and 100 to 3 nights' home CPAP titration and then issued with fixed pressure CPAP. Data were analyzed on an intention-to-treat basis. The patient groups did not differ at baseline. The CPAP pressures defined at titration (mean+/- SEM: 10.6+/-0.2, 10.4+/-0.2 cm H20, p = .19), number of mask leaks, and initial acceptance rates were similar in the sleep-laboratory and home-titrated groups. At 3-month follow-up, there was no significant difference in CPAP use (mean+/-SEM: 4.39+/-0.25, 4.38+/-0.25 h/night; p > .9), Epworth Sleepiness Scale score (9.5+/-0.5, 8.5+/-0.5, p = .14), OSLER, Functional Outcomes of Sleep Questionnaire, or SF-36 between the sleep-laboratory and home-titrated groups. Home-based automated CPAP titration is as effective as automatic in-laboratory titrations in initiating treatment for OSAHS.

Paediatric home ventilatory support: The Auckland experience

To examine the trend over time, describe the disease categories treated, intervention success and outcomes of the children treated at home with continuous positive airway pressure (CPAP), non-invasive ventilation (NIV) and ventilation via tracheostomy (invasive ventilatory support, IVS) by the Respiratory Service at the Starship Children's Hospital in Auckland. A retrospective review was undertaken of the Respiratory Service records from November 1991 to February 2004. Home CPAP, NIV or IVS was initiated in 160 children (89 boys, median age 6 years) in the study period. Sixty-nine (46 boys) remain on support and are still actively managed by the Starship Respiratory Service, of whom 46% live outside the Greater Auckland Region. Despite 42% of children being less than 5 years of age at initiation of therapy, institution of support failed in only 11%. The majority received treatment by non-invasive mask interface (68% (n = 108) CPAP, 29% (n = 47) NIV), with only 3% (n = 5) supported via tracheostomy. The numbers and complexity of support rose over the 12 years. Respiratory support was discontinued in 57% of cases, after a median of 12.5 months (range 3-52 months); in two-thirds, support was no longer required due to an improvement in the medical condition. The most common indication for support in current patients is respiratory parenchymal or airway disease followed by neuromuscular disease. Obesity is not a common indication. This review documents the increasing trend in children receiving respiratory support at home. Future planning and resources are needed to address this growing need.

Continuous Positive Airway Pressure (CPAP) Changes in Bariatric Surgery Patients Undergoing Rapid Weight Loss

Obstructive sleep apnea (OSA) is a common condition in morbidly obese patients, with the reported prevalence ranging from 12-78%. There is increasing recognition of the need to diagnose and treat/manage OSA both preoperatively and postoperatively. Nasal CPAP is the preferred treatment of OSA; however, weight loss is associated with a reduction in required pressures. We evaluated the CPAP pressure requirements in a group of patients undergoing rapid weight loss following Roux-en-Y gastric bypass. 15 patients who had been diagnosed with OSA before surgery were retrospectively evaluated. All patients had demonstrated compliance on home CPAP therapy, were minimally 3 months post-surgery and had follow-up reports that their CPAP was less effective. We obtained data on age, sex, weight, BMI, and apnea/hypopnea index (AHI). Optimal CPAP pressure was obtained initially through attended in-laboratory complex polysomnography. Follow-up CPAP pressure was obtained using an auto-titrating PAP device at home. These data were used to evaluate the pressure changes that accompanied weight loss. This group of patients had lost an average of 44.5 +/- 19.4 kg. Four patients had achieved their goal weight. Their starting CPAP pressures averaged 11 +/- 3.0 cm H2O, with a range of 7-18 cm H2O. Follow-up CPAP pressures averaged 9 +/- 2.7 cm H2O, with a range of 4-12 cm H2O, representing an overall reduction of 18%. The subgroup of patients who had achieved goal weight had a pressure reduction of 22% (9 +/- 2.0 to 7 +/- 1.0 cm H2O). CPAP pressure requirements change considerably in bariatric surgery patients undergoing rapid weight loss. Auto-titrating PAP devices have promise for facilitating the management of CPAP therapy during this time. Consideration should also be given to the use of autotitrating PAP units as the treatment of choice in these patients.

Sleep Structure Correlates of Continuous Positive Airway Pressure Variations During Application of an Autotitrating Continuous Positive Airway Pressure Machine in Patients With Obstructive Sleep Apnea Syndrome

To evaluate the relationship between sleep structure and continuous positive airway pressure (CPAP) delivered by an automatic CPAP (auto-CPAP) machine in patients with obstructive sleep apnea syndrome (OSAS). Nocturnal polysomnography was performed during CPAP administration by an auto-CPAP machine (Autoset Clinical 1; ResMed; Sydney, Australia). Sleep-disorders center in a research institute. Fifteen subjects with newly diagnosed OSAS deserving home CPAP treatment. During the night, in most cases, the lowest CPAP level was recorded during a prolonged nonrapid eye movement (NREM) sleep period uninterrupted by arousals, whereas the highest level during wake-sleep transitions or NREM sleep fragmented by arousals. In four subjects, rapid eye movement sleep was always associated with increasing CPAP. Sleep efficiency was negatively correlated with CPAP variability, evaluated as the SD of the mean nocturnal CPAP level averaged epoch by epoch (r = 0.63, p < 0.02). Eighty-eight percent of rapid CPAP augmentations (increases by at least 2 cm H(2)O in less-than-or-equal 2 min) were observed during sleep-wake transitions or after arousals/awakenings (Ar/Aw); 63% of such Ar/Aw were not preceded by any detectable respiratory abnormality. CPAP levels and variations during auto-CPAP application may be mainly related to sleep continuity and efficiency. The recording of a highly variable pressure during auto-CPAP administration in an unattended environment must raise the question whether the patient's sleep quality was acceptable. A poor sleep quality during an autotitration night could lead to an undesirable overestimation of the CPAP level needed for use with fixed-level CPAP machines.

Continuous positive airway pressure for sleep apnoea/hypopnoea syndrome: usefulness of a 2 week trial to identify factors associated with long term use

BACKGROUNDThe sleep apnoea/hypopnoea syndrome (SAHS) is common and treatment with continuous positive airway pressure (CPAP) is effective. However, not all patients can cope with the demands of using mask positive pressure. Compliance can be improved with an intensive educational programme and patient support, but this is not practical in most centres given the large numbers of patients coming forward for treatment. Several studies have evaluated correlations between various parameters at diagnosis in order to anticipate patients' behaviour and to avoid the social and health implications of undertreated SAHS. We have evaluated the use of additional data derived during a 2 week home CPAP trial to identify factors associated with longer term use of CPAP and compliance.METHODSFollowing a diagnostic study, 209 patients were offered a CPAP machine for a 2 week home trial. After completing the trial, patients were reassessed and scored their overall satisfaction with CPAP treatment on a five point scale ranging from “much worse” to “much better” and an Epworth score relating to the loan period. Machine run time was recorded from the integral clock. These data were added to those available at diagnosis to construct models indicative of continuing CPAP and average nightly use at 1 year.RESULTS209 patients were offered the 2 week loan at least a year before June 1999 (90.9% men, mean (SD) age 51.0 (10.6) years, body mass index (BMI) 34.6 (7.7) kg/m2, Epworth score 15 (IQR 11–18), apnoea/hypopnoea index (AHI) 38.1 (22.9) events/h). 153 patients (73.2%) opted to continue CPAP and 56 declined. One year later data were available for 187 patients; 128 (68.5% on an intention to treat analysis) continued to use the machine with a mean use of 5.0 (2.4) hours/night. A logistic regression model indicated that mean CPAP use during the loan period and the overall satisfaction score accurately defined continuing CPAP and “satisfactory” CPAP use at 1 year. For patients with low machine use and no symptomatic improvement during the loan period, the addition of baseline AHI, baseline Epworth score, and the Epworth score at the end of the loan to the equation identifying factors associated with “satisfactory” CPAP use (mean &gt;2 hours/night) improved the value of the model.CONCLUSIONData derived from a 2 week CPAP trial are useful in identifying patients who will comply with CPAP treatment to 1 year. It can be used to identify patients with significant symptomatic disease who will struggle with CPAP and may benefit from additional education and support. High mean hourly use and a high degree of overall satisfaction during the loan period identified patients likely to use CPAP and be compliant with it at 1 year.

Continuous positive airway pressure for sleep apnoea/hypopnoea syndrome: usefulness of a 2 week trial to identify factors associated with long term use

BACKGROUNDThe sleep apnoea/hypopnoea syndrome (SAHS) is common and treatment with continuous positive airway pressure (CPAP) is effective. However, not all patients can cope with the demands of using mask positive...