Long-term Continuous Positive Airway Pressure Therapy Research Articles

Improved depressive symptoms, and emotional regulation and reactivity, in individuals with obstructive sleep apnea after short- and long-term CPAP therapy use

Obstructive Sleep Apnoea (OSA) is associated with high rates of depression; however, if and how treatment of OSA improves depressive symptoms is unclear. To further understand this link we considered the role of emotional regulation – the ability to control and express our emotional responses – thought to be a central component of depression. This study aimed to assess changes in depressive symptoms and emotional responses in individuals with OSA after 4- and 12-months of continuous positive airway pressure (CPAP) treatment. One-hundred and twenty-one OSA participants (50 female, Mage = 51.93; mean AHI = 36.27) were recruited from a tertiary clinical sleep service prior to CPAP initiation, and randomised to either a CPAP group or a 4 month wait-list group. Participants completed the Center for Epidemiological Studies Depression Scale, the Emotional Reactivity Scale and the Difficulties in Emotion Regulation Scale at baseline, and 1-, 2-, and 4-months follow-up. The CPAP group also completed the questionnaires 12-months after CPAP initiation. CPAP use at 1 month and 12 months was 5.1h/night and 4.9h/night, respectively. Significant improvements in depressive symptoms, emotional regulation and reactivity, and subjective sleepiness were observed after 4 months in both groups, however, the within group changes were only significant for those using CPAP. After 12-months of CPAP treatment, these improvements were maintained. There was no association between CPAP treatment adherence and improvements in any outcome. CPAP treatment for 12 months may reduce symptoms of depression and improve emotional regulation in individuals with OSA.

Residual excessive daytime sleepiness in patients with sleep apnea syndrome receiving continuous positive airway pressure in Japan: A single-center study

Excessive daytime sleepiness (EDS) is a symptom of sleep apnea syndrome (SAS). In some patients with SAS who undergo continuous positive airway pressure (CPAP) therapy, EDS persists (residual EDS). However, knowledge of residual EDS in Japan is limited. Therefore, we examined EDS as defined by the Japanese version of the Epworth Sleepiness Scale (a score of ≥11) before and after long-term (≥1 year) CPAP therapy in 490 patients with SAS. Good adherence to CPAP therapy was defined as its use for at least 4 h during 70% of the nights. The prevalence of residual EDS was 9.4%. Residual EDS was negatively associated with good adherence to CPAP therapy. Furthermore, the longer the CPAP therapy duration after initiation, the lower the prevalence of residual EDS. Therefore, the findings on the prevalence of residual EDS and its association with CPAP therapy in Japan are probably similar to those of other countries.

Endothelial dysfunction in obstructive sleep apnea patients

PurposeObstructive sleep apnea syndrome (OSAS) is an independent risk factor for cardiovascular diseases. The aim of the study was to assess the influence of OSAS on endothelial dysfunction and thrombosis biomarkers and to evaluate the effect of treatment with continuous positive airway pressure (CPAP) on biomarker levels.MethodsNT-proBNP, sICAM-1, endothelin-1, von Willebrand factor, D-dimers, and thrombin-antithrombin complex (TAT) were measured in 50 patients diagnosed with moderate-to-severe OSAS. All patients underwent transthoracic echocardiography, and 38 months after the inclusion, 16 CPAP users and 22 non-CPAP users were reassessed.ResultsSleep-related indices of apnea-hypopnea index (AHI) and mean SpO2 were associated with higher sICAM-1 levels (AHI < 30: 7.3 ± 4.7 vs. AHI ≥ 30: 19.5 ± 19.4 mg/ml, p = 0.04; SpO2 ≥ 90%: 11.9 ± 9.3 vs. SpO2 < 90%: 23.6 ± 25.8, p = 0.04). sICAM-1 levels were significantly higher in obese patients, particularly with BMI ≥ 40. Plasma levels of TAT were significantly correlated with the increased right ventricular size (right ventricular diameter ≤ 37 mm: 0.86 ± 0.70 vs. > 37 mm: 1.96 ± 1.20 ng/ml, p = 0.04). Endothelin-1 levels were higher in patients with decreased right ventricular function (right ventricle TDI-derived S′ ≥ 12 cm/s: 11.5 ± 10.9 vs. < 12 cm/s: 26.0 ± 13.2 pg/ml, p = 0.04). An increase in NT-proBNP was related to impaired parameters of the right ventricular contractile function. There were no correlations between long-term CPAP therapy and the levels of biomarkers.ConclusionSevere OSAS influences endothelial damage as manifested by an increase in sICAM-1 levels. Changes in right ventricular structure and function, observed mainly in patients with higher TAT and endothelin-1 levels, are also manifested by an increase in NT-proBNP levels. Long-term CPAP treatment does not seem to influence biomarkers in patients with moderate-to-severe OSAS, which may help to explain the lack of influence of CPAP on cardiovascular risk reduction.

Effects of continuous positive airway pressure on plasma fibrinogen levels in obstructive sleep apnea patients: a systemic review and meta-analysis.

Objective: Fibrinogen has been implicated to play a role in the pathophysiology of obstructive sleep apnea (OSA). Many studies have evaluated the effect of continuous positive airway pressure (CPAP) on plasma fibrinogen levels in OSA patients. However, results from different reports were not consistent. To assess the effect of CPAP treatment on plasma fibrinogen levels of patients with OSA, a meta-analysis was performed.Methods: A systematic search of Pubmed, Embase, Cochrane, Wanfang Database and Chinese National Knowledge Infrastructure was performed. Data were extracted, and then weighted mean difference (WMD) and 95% confidence intervals (CIs) were calculated using a random-effects model.Results: Twenty-two studies involving 859 patients were included in this meta-analysis. Combined data showed that plasma fibrinogen concentrations decreased after CPAP therapy (WMD = −0.38 g/l, 95% CI [−0.54 to −0.22 g/l], P<0.001). In the subgroup analyses by therapy duration, plasma fibrinogen concentrations declined significantly in the long-term (≥1 month) CPAP therapy subgroup (WMD = −0.33 g/l, 95% CI [−0.49 to −0.16 g/l], P<0.001) but not in the short-term (<1 month) CPAP therapy subgroup (WMD = −0.84 g/l, 95% CI [−1.70 to 0.03 g/l], P=0.058). Moreover, in patients with long-term CPAP therapy duration, plasma fibrinogen levels decreased with good CPAP compliance (≥4 h/night) (WMD = −0.37 g/l, 95% CI [−0.55 to −0.19 g/l], P<0.001) but not with poor CPAP compliance (<4 h/night) (WMD = 0.12 g/l, 95% CI [−0.09 to 0.33 g/l], P=0.247).Conclusion: Long-term CPAP treatment with good compliance can reduce the plasma fibrinogen levels in patients with OSA.

Mood, sleepiness, and weight gain after three years on CPAP therapy for sleep apnoea

ABSTRACT Background: The prevalence of obstructive sleep apnoea syndrome (OSAS) keeps on rising. Daytime sleepiness resulting from fragmented sleep is the prime symptom, and obesity the major risk factor for OSAS. Quality of life with OSAS is often affected by depressive symptoms and anxiety. Nasal continuous positive airway pressure (CPAP) therapy reduces daytime sleepiness, but the results on the effect on mood, physical activity, and weight are controversial especially on long-term therapy. Purpose of this study was to evaluate these factors and predictors of weight gain during long-term CPAP therapy. Methods: Consecutive patients (n = 223), referred to sleep study with suspected OSAS, were enrolled. Patients underwent a cardiorespiratory polygraphy at baseline and a battery of questionnaires was completed, both at baseline, and after three years of follow-up. Total of 149 (67%; M 65, F 84) patients completed the follow-up. Of the 149 patients, 76 (51.0%; M 32, F 44) used CPAP. Results: In this study, depressive symptoms, anxiety, and sleepiness were alleviated during CPAP therapy. However, therapy did not have an influence on cravings of different food categories, or exercise habits and exercise duration. From the various factors studied, solely higher adherence to CPAP therapy was associated with weight gain. Conclusions: This research provides further evidence that long-term CPAP therapy in patients with OSAS not only decreases sleepiness and improves sleep quality but could also alleviate depressive symptoms and anxiety. In addition, our study reinforces that CPAP therapy alone is not sufficient for weight management in patients with OSAS. Regardless of comprehensive battery of questionnaires, we were unable to establish markers predicting weight gain during therapy. We advise on life-style counselling and weight management program to all patients with obesity on CPAP therapy.

Medication of comorbidities in females with sleep-disordered breathing during long-term CPAP therapy.

Treating sleep disordered breathing (SDB) with nasal continuous positive airway pressure (CPAP) may reduce mortality, but the studies on the effect on medication use are few. Women tend to have more mild sleep apnoea and partial airway obstruction and are therefore expected to have less co-morbidity. The purpose of this study was to evaluate the effect of CPAP therapy on medication use in women as overall medication, and in different subcategories of diseases, and to evaluate the impact of nocturnal airway obstruction type as partial or complete. From the database of the Department of Pulmonary Diseases in Turku University Hospital from 1994 to 1998, 601 consecutive females with SDB were enrolled, and the type of SDB was evaluated. All were offered CPAP therapy. The medication use measured as defined daily doses (DDD) in overall medication and in nine subcategories were collected three years before and three years after CPAP initiation. In final analyses, 182 women were included. In CPAP users (n=66), comorbidities were more frequent and DDDs higher overall, in asthma, in chronic obstructive pulmonary disease, and in severe mental disorders, both before and after CPAP initiation. The medication use was similar regardless of the type of SDB. The change in medication use was similar as in controls. CPAP therapy did not decrease medication use in three-year follow-up. However, possibly continuous rise in medication use was prevented, as the change in medication use was similar in controls. Complete and partial obstruction had similar effects.

Dental side effects of long-term obstructive sleep apnea therapy: a 10-year follow-up study.

Patients with obstructive sleep apnea (OSA) are usually treated with either mandibular advancement device (MAD) or continuous positive airway pressure (CPAP) therapy. The objective of this study is to evaluate changes in dental occlusion associated with long-term MAD and CPAP therapy. Data from 14 OSA patients using MAD and 17 OSA patients using CPAP therapy were evaluated at baseline, 2-year and 10-year follow-up. Changes in dental occlusion were analyzed from dental plaster casts with a digital sliding caliper. At 2-year follow-up, MAD therapy resulted in significant dental changes when compared with baseline values. In MAD therapy, overjet and overbite decreased with 1.1 ± 1.8mm and 1.1 ± 1.2mm respectively. With CPAP therapy overjet and overbite decreased significantly with 0.2 ± 0.5mm and 0.3 ± 0.5mm, respectively. Both groups also showed significant changes in molar occlusion. After a 10-year follow-up, significant and more pronounced changes were seen in overjet and overbite. In MAD therapy, overjet and overbite decreased with 3.5 ± 1.5mm and 2.9 ± 1.5mm respectively when compared with baseline values. In CPAP therapy, overjet and overbite decreased with 0.7 ± 1.5mm and 0.8 ± 1.4mm respectively when compared with baseline values. This study demonstrates that MAD and CPAP therapy result in significant changes in dental occlusion. These changes appear progressive and more pronounced with MAD compared to CPAP therapy. Long-term OSA treatment results in significant dental side effects that may progress over time. Informed consent is fundamental before starting MAD treatment and individualized long-term follow-up is of eminent importance.

Predictors of long-term adherence to continuous positive airway pressure in patients with obstructive sleep apnea and cardiovascular disease.

Poor adherence to continuous positive airway pressure (CPAP) commonly affects therapeutic response in obstructive sleep apnea (OSA). We aimed to determine predictors of adherence to CPAP among participants of the Sleep Apnea and cardioVascular Endpoints (SAVE) trial. SAVE was an international, randomized, open trial of CPAP plus usual care versus usual care (UC) alone in participants (45-75 years) with co-occurring moderate-to-severe OSA (≥12 episodes/h of ≥4% oxygen desaturation) and established cardiovascular (CV) disease. Baseline sociodemographic, health and lifestyle factors, OSA symptoms, and 1-month change in daytime sleepiness, as well as CPAP side effects and adherence (during sham screening, titration week, and in the first month), were entered in univariate linear regression analyses to identify predictors of CPAP adherence at 24 months. Variables with p <0.2 were assessed for inclusion in a multivariate linear mixed model with country, age, and sex included a priori and site as a random effect. Significant univariate predictors of adherence at 24 months in 1,121 participants included: early adherence measures, improvement in daytime sleepiness at 1 month, fixed CPAP pressure, some measures of OSA severity, cardiovascular disease history, breathing pauses, and very loud snoring. While observed adherence varied between countries, adherence during sham screening, initial titration, and the first month of treatment retained independent predictive value in the multivariate model along with fixed CPAP pressure and very loud snoring. Early CPAP adherence had the greatest predictive value for identifying those at highest risk of non-adherence to long-term CPAP therapy. SAVE is registered with clinicaltrials.gov (NCT00738179).

Gender-specific change in leptin concentrations during long-term CPAP therapy

PurposeNasal continuous positive airway pressure (CPAP) alleviates sleepiness in patients with obstructive sleep apnoea syndrome (OSAS), but part of OSAS patients keep gaining weight. Leptin and insulin-like growth factor-1 (IGF-1) interact with energy balance, and CPAP therapy has been suggested to influence these endocrine factors. We hypothesised that leptin would decrease during long-term CPAP therapy, and weight gain would associate with OSAS severity, lower CPAP adherence, lower IGF-1, and leptin concentrations.MethodsConsecutive patients (n = 223) referred to sleep study with suspected OSAS were enrolled. Patients underwent cardiorespiratory polygraphy at baseline. Questionnaires were completed, and blood samples were drawn both at baseline and after 3 years. A total of 149 (67%; M 65, F 84) patients completed the follow-up. Plasma samples were available from 114 patients, 109 of which with CPAP adherence data (49 CPAP users, 60 non-users).ResultsAt baseline, the CPAP users were more obese and had more severe OSAS than the non-users. Leptin concentrations did not differ. After follow-up, leptin concentrations were higher in CPAP users (30.2 ng/ml vs. 16.8 ng/ml; p = 0.001). In regression analysis, increase in leptin concentrations was independent of age, baseline body mass index (BMI), or the change in BMI. Leptin concentrations increased among females (− 8.9 vs. 12.7 ng/ml; p < 0.001); whereas in men, CPAP did not have an effect, if not opposed the natural decrease in leptin observed in men not using CPAP. Change in IGF-1 levels did not differ.ConclusionsOur results suggest increase in leptin concentrations during long-term CPAP therapy among females.

Implications of continuous positive airway pressure on heart rate variability in patients with obstructive sleep apnea: Does gender matter?

This study was designed to determine the effectiveness of continuous positive airway pressure (CPAP) treatment on the improvement of heart rate variability (HRV) and whether gender plays a role in HRV in patients with mode-rate to severe obstructive sleep apnea syndrome (OSAS). Consecutive patients with recently diagnosed moderate to severe OSAS underwent continuous synchronized electrocardiographic monitoring and were prospectively considered for inclusion in the study. HRV was analyzed before starting CPAP therapy and 1 year thereafter. The effects of CPAP on HRV were evaluated in men and women separately to ascertain whether there are gender differences in the clinical manifestations of OSAS and whether female HRV responses to CPAP are similar to those of men. A total of 18 patients (10 men, median age: 56 years) were included in the study. There were no significant differences in the baseline clinical characteristics of the male and female patients. After 1 year of CPAP treatment, heart rate decreased (p<0.05) and time domain parameters increased (p<0.05) in both men and women. None of the frequency domain parameters changed in women (p<0.05), whereas the high frequency power measured increased (p<0.05) and the ratio of low frequency to high frequency decreased (p<0.05) in men after 1 year of CPAP treatment. The increase in HRV after 1 year of CPAP therapy was significantly higher in men than in women (p<0.05). CPAP therapy reduced enhanced cardiac sympathetic nerve activity in patients with OSAS assessed according to HRV. The beneficial effect of long-term CPAP therapy on HRV was more pronounced in men.

Long-term Effect of Continuous Positive Air Pressure Therapy on Intraocular Pressure in Patients with Primary Open-angle Glaucoma with Obstructive Sleep Apnea.

ABSTRACTPurposePrevalence of glaucoma is higher in obstructive sleep apnea (OSA) patients. The gold standard technique to treat OSA is continuous positive airway pressure (CPAP) therapy. The influence of long-term CPAP therapy on intraocular pressure (IOP), blood pressure, ocular perfusion pressure (OPP), and glaucoma progression in primary open-angle glaucoma (POAG) patients was evaluated.DesignProspective study.Materials and methodsIn this study, we enrolled 12 eyes from six POAG patients aged >35 years, with newly diagnosed OSA and with indication for CPAP therapy. The CPAP was performed for 12 months. We monitored the IOP every 3 months. Visual field was determined at baseline and 12 months.ResultsThe mean IOP after CPAP therapy for 12 months was significantly higher than the mean baseline IOP (average IOP 3 months before CPAP therapy) (19.08 ± 3.47 vs 17.83 ± 2.88 mm Hg; p = 0.006). The IOP rising rate was 0.69 ± 0.47/years (p = 0.138) before CPAP therapy and increased to 1.13 ± 0.47/years (p = 0.016) after CPAP therapy. The OPP after 12 months of CPAP was significantly lower than the baseline (42.21 ± 5.29 vs 45.24 ± 7.09 mm Hg; p = 0.06). Results showed that the pattern standard deviation (PSD) value of 24-2 short wavelength automated perimetry (SWAP) visual field was reduced from 5.34 ± 3.92 to 4.77 ± 3.73 (p = 0.025). Antiglaucoma medication was administered to a patient due to increased IOP without glaucoma progression evidence.ConclusionThe POAG and OSA patients demonstrated significant IOP rising after CPAP therapy but did not show progression of glaucomatous damage. Mean deviation (MD), PSD, and visual field index (VFI) were not significantly different after CPAP therapy.PrécisProspective study of POAG and OSA patients demonstrated significant IOP rising after CPAP therapy for a year. The study did not show progression of glaucomatous damage.How to cite this articleHirunpatravong P, Kasemsup T, Ayudhya WN, et al. Long-term Effect of Continuous Positive Air Pressure Therapy on Intraocular Pressure in Patients with Primary Open-angle Glaucoma with Obstructive Sleep Apnea. J Curr Glaucoma Pract 2019;13(3):94–98.

CPAP therapy improves erectile function in patients with severe obstructive sleep apnea

ObjectivesErectile dysfunction (ED) is highly prevalent in obstructive sleep apnea (OSA), however, the effect of continuous positive airway pressure (CPAP) therapy on erectile function has not yet been thoroughly investigated in these patients. MethodsNinety-four men with severe OSA (ie, with an apnea-hypopnea-index ≥ 30/h of sleep) were prospectively evaluated for the presence and severity of ED before and after 6–12 months of CPAP therapy. The abbreviated version of the International Index of Erectile Function, (the IIEF-5) was used to rate erectile function. Furthermore, all study participants responded to standard questionnaires of daytime sleepiness (Epworth Sleepiness Scale), quality of life (WHO Wellbeing 5 questionnaire) and depression (Major Depression Inventory). ResultsED as defined by an IIEF-5 score of ≤21 was present in 64 patients (68.1%). CPAP treatment significantly improved erectile function in those patients suffering from moderate and severe ED. Additionally, a trend for a correlation between the improvement of erectile function under CPAP and the hours of its use was observed. Finally, this effect was associated with larger improvements of quality of life in affected patients. ConclusionsED is very frequent in men with severe OSA and can at least partly be reversed by long-term CPAP therapy in most seriously affected patients. The beneficial effect on erectile function may depend on CPAP compliance and is accompanied by improvements of quality of life. Randomized controlled trials are needed to confirm these findings.

Impact of long-term continuous positive airway pressure on liver fat in male obstructive sleep apnea patients with fatty liver

Obstructive sleep apnea (OSA) is an established factor in the pathogenesis and exacerbation of fatty liver disease. However, randomized controlled trials have failed to demonstrate decreases in liver fat content in OSA patients by continuous positive airway pressure (CPAP) performed for several months. The aim of this study is to investigate the impact of long-term CPAP therapy on liver fat content in OSA patients with fatty liver. Liver fat content in 61 male OSA patients was evaluated by computed tomography performed because of abdominal obesity before and after CPAP initiation. At baseline, there were 25 participants with fatty liver. Their apnea–hypopnea index and percent sleep time with oxygen saturation < 90% were greater than those in the 36 participants who did not have fatty liver (52.3 vs. 41.8/h and 30.4 vs. 14.8%, respectively). The average therapy duration was 31 months. In the analysis of the entire participant group, liver fat content did not change after CPAP therapy. In those without fatty liver, liver fat content increased accompanied by increases in BMI, whereas in the participants with fatty liver, liver fat content decreased despite stable BMI, abdominal fat distribution, and insulin resistance. In male OSA patients with abdominal obesity, decreases in liver fat content were observed after long-term CPAP therapy only when fatty liver was present at baseline. This implies that there are some conditions, such as OSA-related hypoxemia and others, which may exacerbate fatty liver and that fatty liver may improve with CPAP therapy.

Measurement of exhaled nitric oxide concentration in patients with obstructive sleep apnea: A meta-analysis.

Exhaled nitric oxide (eNO) has been proposed as a noninvasive measure of airway inflammation. However, its value in patients with obstructive sleep apnea (OSA) is still controversial. The authors aim to assess the difference in eNO levels between patients with OSA and controls by a meta-analysis. A systematic search was performed in the PubMed, EMBASE, the Cochrane Library, and MEDLINE databases to collect relevant studies published from 1996 to 2016. Eligible studies that reported eNO levels in patients with OSA were included. STATA (version 12.0) was used for data analysis. Two hundred eighty-four studies were reviewed for inclusion, with 16 studies pooled for analysis (16 studies for fractional exhaled nitric oxide [FENO], 5 for alveolar nitric oxide [CANO], and 4 for the maximum airway wall flux of nitric oxide [J'awNO]). The FENO levels were significantly higher in patients with OSA compared with that in the control groups (6.32 ppb, 95% confidence interval [CI] 4.46-8.33, P < 0.001). Furthermore, FENO was significantly increased (4.00 ppb, 95% CI 1.74-6.27, P = 0.001) after overnight sleep in patients with OSA, but not in healthy controls. Additionally, long-term continuous positive airway pressure (CPAP) therapy reduced FENO levels (-5.82 ppb, 95% CI -9.6 to -2.01, P < 0.001). However, the CANO (-0.01 ppb, 95% CI -1.66 to 1.64, P = 0.989) and J'awNO levels (220.32 pl/s, 95% CI -49.31 to 489.94, P = 0.109) were not significantly different between the OSA groups and non-OSA groups. The results of the meta-analysis suggest that OSA is significantly associated with airway inflammation and elevated FENO levels can be modified by long-term CPAP therapy. J'awNO and CANO levels were not significantly different between the OSA groups and control groups.

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.

Comparison of CPAP adherence in two European sleep centres

There is a lack of comparative data on long-term adherence to continuous positive airway pressure (CPAP) therapy in different countries. This study compared data on long-term subjective and objective adherence to CPAP therapy from two sleep research centres, one in Berlin, Germany, the other in Tampere, Finland. The objective was to compare adherence to CPAP therapy in order to identify predictors of good CPAP adherence. Retrospective data from obstructive sleep apnoea(OSA)-patients already undergoing CPAP therapy at sleep centres in Berlin and Tampere were collected. Data included subjective adherence (questionnaire), objective adherence (device data), patient demographics and clinical data. Potential selection bias of patients was carefully checked in both centres. After manual titration, there were significant differences in adherence between patients treated in Berlin (mean 6.14 ± 0.23 h/night) vs. Tampere (mean 4.24 ± 0.24 h/night; p < 0.001). Adherence to CPAP therapy was significantly better in patients with manual titration compared to automatic titration (p < 0.002). Patients tended to overestimate subjective adherence to CPAP. Hypertension has a significant influence on adherence. This study reports significant differences in long-term CPAP therapy adherence between two sleep research centres in different countries for the first time. The differences might result from different management of adverse effects, as well as from variation in the prevalence of comorbid hypertension, titration methods and other patient care procedures.

Protective Effect of Long-Term CPAP Therapy on Cognitive Performance in Elderly Patients with Severe OSA: The PROOF Study.

Obstructive sleep apnea syndrome (OSA) leads to a deterioration in cognitive functions, with regard to memory and executive functions. However, few studies have investigated the impact of treatment on these cognitive functions in elderly subjects. The study was conducted in a large cohort of subjects aged 65 years or older (the PROOF cohort). Subjects were not diagnosed or treated for OSA. Subjects underwent a polygraphic recording. Cognitive performance was assessed in all OSA subjects at baseline and 10 years later, whether or not they were receiving continuous positive airway pressure (CPAP) therapy. A group of 126 patients were analyzed. Only 26% of them were treated, with therapy initiated at the discretion of the primary care physician. Among treated subjects, self-reported compliance with therapy was good (> 6 h/night on average), and 66% of them reported an improvement in their quality of life. Patients receiving CPAP treatment had a higher apneahypopnea index (p = 0.006), a higher oxygen desaturation index (p < 0.001), and experienced more pronounced daytime repercussions (p = 0.004). These patients showed a statistically significant improvement in mental agility (similarities test; p < 0.0001) and memory performance (Grober and Buschke delayed free recall; p = 0.02). CPAP treatment is associated with the maintenance of memory performance over time.

The Prevalence and Natural History of Complex Sleep Apnea

Central sleep apnea (CSA) may occasionally occur in patients with obstructive sleep apnea during titration with a continuous positive airway pressure (CPAP) device. To determine the prevalence and the natural history of CPAP-emergent CSA. This is a retrospective study of 1286 patients with a diagnosis of OSAwho underwent titration with a positive airway device during a 1-year period. Patients were seen in consultation and underwent full-night attended polysomnography followed by full-night attended CPAP titration. Four weeks after CPAP therapy, patients returned to the clinic for follow-up, and objective adherence to CPAP was recorded. In patients who had CSA on CPAP, a second full-night attended CPAP titration was recommended. Eighty-four of the 1286 patients developed a central apnea index (CAI) of 5 or greater per hour while on CPAP. The incidence of CSA varied from 3% to 10% monthly, with an overall incidence of 6.5%. Forty-two of the 84 patients returned for a second CPAP titration. In 33 patients, CSA was eliminated. In each of the remaining 9 patients, the CAI remained at 5 or greater per hour, with an average of 13 per hour. These patients characteristically had the most severe OSA, and 5 had a CAI of 5 or more per hour at baseline. Two of the 9 patients were on opioids In this large retrospective study of 1286 patients with a diagnosis of OSA, 6.5% had CPAP-emergent or persistent CSA. However, CPAP-emergent CSA was generally transitory and was eliminated within 8 weeks after CPAP therapy. The prevalence of CPAP-persistent CSA was about 1.5%. Severity of OSA, a CAI of 5 or greater per hour, and use of opioids were potential risk factors.

A Continuous Positive Airway Pressure Trial as a Novel Approach to the Diagnosis of the Obstructive Sleep Apnea Syndrome

Treatment of obstructive sleep apnea syndrome (OSA) is often delayed because polysomnography, the recommended standard diagnostic test, is not readily available. We evaluated whether the diagnosis of sleep apnea could be inferred from the response to a treatment trial with nasal continuous positive airway pressure (CPAP). Study on diagnostic accuracy. Sleep-disorders clinic of a university hospital. Seventy-six sleepy snorers consecutively referred for sleep apnea evaluation. CPAP treatment trial over 2 weeks as an initial diagnostic test in comparison with polysomnography, and treatment success over > or = 4 months. The main outcome was diagnostic accuracy of the CPAP trial. The trial result was positive if the patient had used CPAP for > 2 h per night and wished to continue therapy. This suggested sleep apnea. The trial was evaluated in terms of predicting an obstructive apnea/hypopnea index (AHI) > 10/h during polysomnography performed for validation, and in terms of identifying sleep apnea patients treated successfully over > or = 4 months. Forty-four of 76 patients (58%) had sleep apnea as confirmed by an AHI > 10/h. The CPAP trial predicted sleep apnea with a sensitivity of 80%, a specificity of 97%, and positive and negative predictive values of 97% and 78%, respectively. In 35 of 76 sleep apnea patients (46%) with positive CPAP trial results, polysomnography could have been avoided. These patients were prescribed long-term CPAP therapy. After 4 months, 33 of 35 patients (94%) still used CPAP, and their symptoms remained improved. These patients were identified by the CPAP trial with positive and negative predictive values of 92% and 100%, respectively. In a selected population, a CPAP trial may help to diagnose OSA, to identify patients who benefit from CPAP, and to reduce the need for polysomnography.

Oral Continuous Positive Airway Pressure for Sleep Apnea: Effectiveness, Patient Preference, and Adherence

Nasal continuous positive airway pressure (CPAP) is the most definitive medical therapy for obstructive sleep apnea (OSA). Many patients have difficulty tolerating nasal CPAP due to nasal airway problems, mouth leak, and general discomfort from the mask and headgear. These limitations may be overcome by an oral mask (Oracle; Fisher & Paykel Healthcare; Languna Hills, CA) that does not require headgear. We performed a study to compare the Oracle mask to conventional nasal and oronasal masks in the effectiveness of CPAP delivery and patient satisfaction and adherence. Ninety-eight, consecutive CPAP-naïve patients with OSA diagnosed by overnight polysomnography (apnea-hypopnea index [AHI] > 5) were referred for CPAP therapy. All patients were presented with a variety of CPAP masks, including nasal, oronasal, and Oracle, and reasons for mask choice were documented. After 3 weeks of acclimatization to the mask of their choice, patients had a CPAP titration sleep study to determine their optimal CPAP level. Further follow-up was obtained 2 months and 6 months later with a subjective patient assessment of CPAP use and efficacy, mask comfort, and upper airway dryness. Patients were predominantly male (70%), middle aged (50.6 +/- 11.7 years), and moderately obese (body mass index, 32.5 +/- 9.0) with severe OSA (AHI, 40.6 +/- 25.8/h) [mean +/- SD]. Patients were classified into three groups based on their choice of mask: nasal (66%), Oracle (27%), and oronasal (7%). Baseline characteristics did not differ significantly between groups. Optimal CPAP was not significantly different between mask groups (nasal, 7.7 +/- 2.1 cm H(2)O; Oracle, 8.0 +/- 2.0 cm H(2)O; oronasal, 9.7 +/- 3.2 cm H(2)O; p = 0.267). Subjective ratings of adherence, efficacy, and mask comfort were also similar between groups. However, the Oracle group had more complaints of upper airway dryness and "rain-out." The oronasal group had a disproportionately greater number of dropouts from CPAP therapy than the Oracle group (57% vs 19%, p = 0.046). Nine patients changed from the Oracle mask to a nasal mask during the study, whereas no patients changed from their nasal or oronasal masks. The Oracle mask is an efficacious interface for long-term CPAP therapy in patients with OSA. The main limitations of the mask are upper airway dryness and rain-out associated with heated humidification, which may be improved by further technical modifications. Oracle may be more acceptable than oronasal masks for patients who cannot rely exclusively on the nasal airway for CPAP therapy.