Obstructive Sleep Apnea-hypopnea Patients Research Articles

Diurnal changes of retinal microvascular circulation and RNFL thickness measured by optical coherence tomography angiography in patients with obstructive sleep apnea-hypopnea.

PurposeTo evaluate capillaries perfusion and retinal nerve fiber layer (RNFL) thickness diurnal changes of macular/optic disc regions among participants with or without obstructive sleep apnea-hypopnea (OSA) using spectral-domain optical coherence tomography angiography (OCTA).MethodsIn this study, we enrolled a cohort of 35 participants including 14 patients with mild-to-moderate OSA, 12 patients with severe OSA, and 9 healthy individuals. All participants had Berlin questionnaire filled. At 20:00 and 6:30, right before and after the polysomnography examination, a comprehensive ocular examination was conducted. The systemic and ocular clinical characteristics were collected, and OCTA scans were performed repeatedly. Blood flow and RNFL thickness parameters were then exported using built-in software and analyzed accordingly.ResultsAfter sleep, the overall vessel density (VD) variables, especially macular and choriocapillaris VDs, were relatively comparative and stable. One exception was the RPC vessel density at the inside-disc region with a decreasing trend in the mild-to-moderate group (p=0.023). RNFL changes before and after sleep in the nasal-inferior and peripapillary region were statistically significant (p=0.003; p=0.043) among three groups. And multiple testing correction verified the significant difference in diurnal changes between the mild-to-moderate group and the control group in pairwise comparisons (p=0.006; p=0.02).ConclusionsThe changes of imperceptible blood flow and RNFL thickness overnight around optic disc areas could be observed in OSA patients. Despite physiological fluctuations, aberrant diurnal changes might be useful for identifying a decrease in micro-environmental stability associated with the development of various ocular diseases such as glaucoma. Other VD variables, especially macular and choriocapillaris VDs, are relatively stable in eyes of patients having OSA with different severity.

Phenotyping OSAH patients during wakefulness.

Although currently there are simplified methods to measure the pathophysiological traits that stimulate the occurrence and maintenance of obstructive sleep apnea-hypopnea (OSAH), they remain difficult to implement in routine practice. This pilot study aimed to find a simpler daytime approach to obtain a meaningful, similar pathophysiological phenotypic profile in patients with OSAH. After obtaining diagnostic polygraphy from a group of consecutive patients with OSAH, we performed the dial-down CPAP technique during nocturnal polysomnography and used it as reference method. This allowed assessment of upper airway collapsibility, loop gain (LG), arousal threshold (AT), and upper airway muscle gain (UAG). We compared these results with a daytime protocol based on negative expiratory pressure (NEP) technique for evaluating upper airway collapsibility and UAG, on maximal voluntary apnea for LG, and on clinical predictors for AT. Of 15 patients studied, 13 patients with OSAH accurately completed the two procedures. There were strong (all r2 > 0.75) and significant (all p < 0.001) correlations for each phenotypic trait between the measurements obtained through the reference method and those achieved during wakefulness. It is possible to phenotype patients withOSAH from a pathophysiological point of view while they are awake. Using this approach, cutoff values corresponding to those usually adopted using the reference method can be identified to detect abnormal traits, achieving profiles similar to those obtained through the dial-down CPAP technique.

Effect of continuous positive airway pressure treatment of obstructive sleep apnea-hypopnea in multiple sclerosis: A randomized, double-blind, placebo-controlled trial (SAMS-PAP study)

Objective: The aim of this study was to evaluate the effect of continuous positive airway pressure (CPAP) treatment on the Fatigue Severity Scale (FSS, preplanned primary outcome), another fatigue measure, sleep quality, somnolence, pain, disability, and quality of life in multiple sclerosis (MS) patients with obstructive sleep apnea-hypopnea (OSAH). Methods: In a randomized, double-blind trial (NCT01746342), MS patients with fatigue, poor subjective sleep quality, and OSAH (apnea-hypopnea index of ⩾ 15 events per hour/sleep), but without severe OSAH (apnea-hypopnea index > 30, and 4% oxygen desaturation index > 15 events/hour or severe somnolence), were randomized to fixed CPAP or sham CPAP for 6 months. Outcome assessments were performed at 3 and 6 months. Results: Of 49 randomized patients, 34 completed the protocol. Among completers, FSS did not improve with CPAP compared to sham at 6 months. FSS tended to improve (p = 0.09), and sleepiness (Epworth Sleepiness Scale) improved significantly (p = 0.03) at 3 months with CPAP compared to sham, but there were no other improvements with CPAP at either study evaluation. Conclusion: In non-severe OSAH patients, CPAP did not significantly improve the primary outcome of FSS change at 6 months. In secondary analyses, we found a trend to improved FSS, and a significant reduction in somnolence with CPAP at 3 months.

The differences in plasma/serum ghrelin levels between obstructive sleep apnea-hypopnea patients and controls: A protocol for systematic review and meta-analysis.

Background:The association between obstructive sleep apnea-hypopnea syndrome (OSAHS) and plasma/serum ghrelin levels remains controversial. We performed a meta-analysis to evaluate the difference in plasma/serum ghrelin levels between OSAHS patients and controls.Methods:Database of PubMed, SCI, and Elsevier were searched entirely. Two independents identified eligible studies of ghrelin levels in OSAHS patients. ReviewManager (version 5.3) was adopted for data synthesis.Results:The meta-analysis A pooled the comparison of ghrelin concentrations in OSAHS patients and controls, which included 7 studies and involving 446 participants. The result of the meta-analysis A indicated that plasma/serum ghrelin levels were no significant differences between the OSAHS group and the control group (standard mean difference (SMD) = 0.08, 95% confidence interval (CI) = −0.12 to 0.28, P = .43). As a supplementary, meta-analysis B pooled the comparison of plasma/serum ghrelin levels in OSAHS patients before and after continuous positive airway pressure (CPAP) therapy, which included 155 participants from 4 studies, it revealed that plasma/serum ghrelin levels were no significant differences between before and after CPAP therapy (SMD = 0.12, 95%CI = −0.07 to 0.31, P = .22).Conclusion:The meta-analysis A demonstrated that plasma/serum ghrelin levels were no significant differences between the OSAHS group and the control group. The meta-analysis B showed plasma/serum ghrelin levels have no significant changes after CPAP therapy in OSAHS patients.

Quantitative evaluation of retinal microvascular circulation in patients with obstructive sleep apnea-hypopnea using optical coherence tomography angiography.

To compare capillaries perfusion in macular areas at different layers and peripapillary region in radial peripapillary capillaries (RPC) between healthy subjects and subjects with obstructive sleep apnea-hypopnea (OSA) using spectral-domain optical coherence tomography angiography (OCTA). Totally 16 eyes with mild-to-moderate OSA, 14 eyes with severe OSA and 22 control eyes were enrolled in this study. Every subject filled out the Berlin questionnaire and received a comprehensive ocular and physical examination. The clinical characteristics were collected, OCT and OCTA scans using OCTA RT XR Avanti (AngioVue software, Optovue Inc., Fremont, CA, USA) were performed and analyzed. Compared to the control group, the severe group had significantly higher VD in parafovea and perifoveal regions (p = 0.031; p = 0.029) at the level of deep capillary plexus (DCP), whereas the mild-to-moderate group had a significantly lower VD in the peripapillary region on RPC network in disc areas (p = 0.013). Blood flow changes in macular areas might first appear at the DCP layer in OSA patients. Reduced VD in the peripapillary region at the RPC layer might be associated with OSA and cause subsequent RNFL changes.

Factors Influencing Adherence to Auto-CPAP: An Observational Monocentric Study Comparing Patients With and Without Cardiovascular Diseases.

Introduction: Obstructive sleep apnea/hypopnea (OSAH) affects more than 15% of the general population and increases the occurrence of cardiovascular (CV) and metabolic events. Continuous positive airway pressure (CPAP) treatment is currently the gold standard treatment of OSAH and could prevent the occurrence of such events. However, long-term adherence to CPAP is a problem where a significant rate stop device treatment use. OSAH patients suffering CV disease could be less compliant due to less diurnal symptoms.Methods: We performed a prospective study of 408 non-CV or CV disease patients suffering severe OSAH syndrome and followed them during the first 5 months as well as a mean of 3 years of CPAP treatment use.Results: We demonstrated that in adult OSAH patients that two variables were associated with a low compliance (<5 h/night): age <60 y and lower maximal positive airway pressure level used. There was no significant impact of the presence of CV disease on compliance of 5 months. After 3 years of CPAP, age <60 y as well as diabetes were independent factors of low compliance. There was no significant association between gender, mask types, 90th centile positive airway pressure level, apnea/hypopnea index and short- or long-term compliance in our population.Conclusions: We did not find lower compliance of CPAP in CV OSAH patients. Most of our population (68–73%) demonstrated an optimal night treatment duration at 3 years of follow-up, allowing a reduction of CV occurrence or recurrence. We hypothesize that an early and short education of OSAH as we routinely proposed could allow a significant increase in the optimal observance of CPAP in at-risk populations.

Exercise tolerance in obstructive sleep apnea-hypopnea (OSAH), before and after CPAP treatment: Effects of autonomic dysfunction improvement

BackgroundObstructive sleep apnea hypopnea (OSAH) is associated with decreased exercise tolerance and autonomic abnormalities and represents a risk for cardiovascular diseases. The aim of the study was to evaluate the effects of CPAP on cardiovascular autonomic abnormalities and exercise performance in patients with OSAH without changes in lifestyle and body weight during treatment. MethodsTwelve overweight subjects with OSAH underwent anthropometric measures, autonomic cardiovascular and incremental symptom-limited cardio-respiratory exercise tests before and after two months of treatment with CPAP. ResultsLower frequency component of power spectrum of heart rate variability (59.5±24.2 msec2 vs 43.2±25.9 msec2; p<0.05) and improvements of maximal workload (99.3±13.5 vs 108.3±16.8%pred.; p<0.05) and peak oxygen consumption (95.3±7.6 vs 105.5±7.9%pred.; p<0.05) were observed in these patients after CPAP, being their BMI unchanged. ConclusionsCPAP-induced decrease of sympathetic hyperactivity is associated with better tolerance to the effort in OSAH patients that did not change their BMI and lifestyle, suggesting that OSAH limits per se the exercise capacity.

Analysis of the dynamic changes in the soft palate and uvula in obstructive sleep apnea-hypopnea using ultrafast magnetic resonance imaging

Apnea and the respiratory cycle are dynamic processes in obstructive sleep apnea-hypopnea (OSAH), which occur only during sleep. Our study aimed to observe the dynamic changes in the soft palate and the uvula during wakefulness and sleep using ultrafast magnetic resonance imaging (UMRI) to provide reference data for the pathogenesis and treatment of OSAH. The dynamic changes in the soft palate and uvular tip of 15 male patients (average age: 50.43 ± 9.82 years) with OSAH were evaluated using UMRI of the upper airway while asleep and awake after 1 night of sleep deprivation. A series of midline sagittal images of the upper airway were obtained. The distance from the center of the soft palate to the x-axis (an extended line from the anterior nasal spine to the posterior nasal spine), from the uvular tip to the x-axis, from the center of the soft palate to the y-axis (a perpendicular line from the center of the pituitary to the x-axis), and from the uvular tip to the y-axis (designated as PX, UX, PY, and UY, respectively) were measured during sleep and wakefulness. The minimum PX, PY, UX, and UY were shorter during sleep than during wakefulness, whereas the maxima were longer during sleep (P < 0.01), the differences between the maximum and minimum PX, PY, UX, and UY were larger during sleep (P < 0.01). The upward, downward, forward, and backward ranges of movement of the soft palate and the uvular tip were larger during sleep in OSAH patients. This increased compliance may trigger each airway obstructive event.

Clinical and polysomnographic differences between OSAH patients with/without excessive daytime sleepiness

The purpose of this study is to describe the clinical and polysomnographic differences found in patients diagnosed with obstructive sleep apnea-hypopnea (OSAH), with or without excessive daytime sleepiness (EDS) measured by the Epworth Sleepiness Scale (ESS). A physical examination, ESS, and polysomnography were applied to all the participants, considering an ESS score of >10 to indicate EDS and an ESS score of ≥ 16 to indicate severe EDS. Univariate (chi-squared or Student's t test) and multivariate (multiple logistic regression) analysis approaches were used. A value of p < .05 was considered statistically significant. The study covered 151 OSAH patients, including 129 (85 %) male patients, 66 (44 %) with EDS and 23 (21 %) with severe EDS. In the univariate analysis of demographic and polysomnographic variables, a comparison between patients without and with EDS showed that the latter had a larger neck circumference, maximum O2 desaturation, and increased sleep time at <90 % O2 saturation, with significant statistical differences. In the multivariate analysis, this statistical significance disappears. A comparison between patients without EDS and with severe EDS did not reveal differences in demographic or polysomnographic variables. Patients with OSAH and ESD showed more hypoxemia, but we did not find significant differences between OSAH patients with or without EDS.

Sleep Disordered Breathing after Stroke: Clinical Profile of Patients with Obstructive- as Opposed to Central-Sleep Apnea

Aim: In order to define the clinical and instrumental profile of patients with Obstructive Sleep Apnea/Hypopnea (OSAH) and to compare them with that of cases with Central Sleep Apnea/Hypopnea (CSAH), a series of stable strokes were studied. Methods: Thirty four patients were submitted to both clinical and polisomnographyc study (PSG) after 4 months of stroke. A Sleep Disordered Breathing (SDB) was diagnosed in all cases with an AHI>5. Patients were classified as affected by predominantly OSAH (pOSAH), predominantly CSAH (pCSAH), or normal patients. Comparisons were made among the groups and correlation analyses were done in each group. Significance was set at p<0.005. Results: Thirty-four ischemic strokes were enrolled (55% embolic, 6% large artery, 32% lacunar, 9% with undetermined cause). The 76% of them had a SDB ( pOSAH=61%; pCSAH=39%). Nearly the 47% of cases had an obstruction of the upper airways alone or combined with an increase in pharyngeal tissue. No significant differences were found between pOSAH and pCSAH. In pOSAH cases, 8 cases (50%) had an obstruction of the upper airways; in 4 of them it was combined with an increase in pharyngeal tissue; the time interval from stroke to PSG (Δ t), was inversely related to both TST (p 0.017) and TSP (p 0.039); the NIH-SS at entry was directly related to the number of arousals /h of sleep (p 0.044); the more severe AHI the higher is ODI (p 0.000). In the pCSAH group, 4 cases (40%) had an obstruction of the upper airways combined with an increase in pharyngeal tissue; two of these 4 cases had also a BMI>30. In CSAH, Δt was inversely related to SE Index (p 0.021), and directly related to both the number of arrhythmias/h sleep (p 0.016) and ODI (p 0.033). No correlations were found between the number of arrhythmias/h sleep and causes of stroke both in pOSAH and in pCSAH groups. Conclusions: Our data suggest a direct effect of stroke on the peripheral breathing system with subsequent alteration of loop gain and CSAH phenotype, at least in a subgroup of cases. To confirm this hypothesis multicenter clinical sleep studied are needed.

Effects of CPAP on systemic hypertension in OSAH: A monocentric, observational, cohort study

Obstructive sleep apnea-hypopnea (OSAH) is a risk factor for development of systemic arterial hypertension (SAH) and can worse the control of established SAH. We investigated the effects of long-term continuous positive airway pressure (CPAP) treatment in controlling and preventing SAH in a large cohort of subjects referred for sleep study for suspected OSAH. In 495 subjects of whom 422 with OSAH and 73 without OSAH, the clinical history was obtained, arterial blood pressure was measured and the current anti-hypertensive drugs was recorded at diagnosis and/or at CPAP start. Subjects were interviewed after a follow-up period of (mean ± SD) 3.4 ± 2.2 yr (range 1-8 yr) and divided in patients with moderate-to-severe OSAH (n = 125) who referred to use CPAP regularly for at least 4 h every night (group 1), with moderate-to-severe OSAH (n = 70) who refused or abandoned the CPAP treatment after few weeks (group 2), with mild OSAH (n = 227) with no CPAP indication (group 3) and simple snorers or normals (n = 73) (group 4). For each group clinical status, BMI, and changes in SAH therapy and occurrence of SAH were assessed at the follow-up. At the follow-up, a higher risk of increasing treatment for SAH was found for group 2 and group 3 versus group 1 (OR = 5, 95%CI 1-20, p < 0.01 and OR = 3, 95%CI 1-10, p < 0.05), respectively. The occurrence of SAH was lower (p < 0.001) in the group 1 (1.9%), vs group 2 (35.9%), 3 (21.1%) and 4 (18.6%). In moderate-to-severe OSAH patients, long-term CPAP treatment significantly reduces the development of SAH and, in those with SAH at baseline, the need of anti-hypertensive drugs.

Using a generic measure of quality of life in patients with obstructive sleep apnea

To evaluate the utility of a Multicultural Quality of Life Index (MQLI) in patients with Obstructive Sleep Apnea-Hypopnea (OSAH). Physical examination, MQLI and the Epworth Sleepiness Scale (ESS) were applied to participants. In addition, a polysomnography or a respiratory polygraphy was carried out. A total of 221 patients participated, 186 (84%) males, mean age 48.8 ± 11.8 years. The MQLI scores 7were .73 ± 1.45 and the ESS 9.9 ± 5.2. A total of 188 (85%) patients had OSAH: 40 (21%) mild, 43 (23%) moderate, and 105 (56%) severe. The average time to answer the MQLI was 3.5 min. Cronbach's alpha index was 0.930. MQLI score in patients with and without OSAH was 7.73 versus 7.75 (p = 0.949); and by severity: non-OSAH 7.75, mild 8.04, moderate 8.14, and severe 7.44 (p = 0.023). There was a slight correlation between MQLI score and Apnea-Hypopnea Index in total population, but it disappeared when we analyzed by severity. MQLI and ESS correlation was R = -0.3256 (p < 0.0001). The MQLI has limitations in identifying quality of life (QOL) alterations and a poor correlation with severity in OSAH patients. The MQLI quantifies QOL in a general way. We recommend supplementing the QOL evaluation with disease-specific instruments.

Short- and long-term effects of CPAP on upper airway anatomy and collapsibility in OSAH

In obstructive sleep apnea hypopnea (OSAH) patients, an increase of upper airway (UA) collapsibility has been described together with a reduced UA caliber due to inflammation, edema, and fat accumulation in pharyngeal walls. CPAP is the main treatment of OSAH and acts mechanically by increasing pressure inside UA. The aim of this study was to assess the short- and long-term effects of CPAP on UA caliber and collapsibility in severe OSAH patients. Ten obese patients (nine male, age 55+/- 9 yr, BMI 35.1 +/- 6.1, Epworth sleepiness scale 12.3 +/- 3.6 point, AHI 58.8 +/- 27.1) had measurements of oropharingeal junction area (OPJ), mean pharyngeal area (APmean), maximal pharyngeal area (APmax) by acoustic pharyngometry and determination of expired volume in the first 0.5 s after the application at the mouth of -5 cmH(2)O negative expiratory pressure (V,NEP(0.5)) during wakefulness in the supine position under basal conditions (baseline) and after 1 week and 6 months of CPAP treatment. OPJ was 0.74 +/- 0.28 cm(2) at baseline, 0.90 +/- 0.24 cm(2) after 1 week and 1.05 +/- 0.31 cm(2) after 6 months (1 week and 6 months vs baseline p < 0.05). APmax was 2.28 +/- 0.74 cm(2) at baseline, 2.79 +/- 0.90 cm(2) after 1 week and 2.94 +/- 0.33 cm(2) after 6 months (1 week and 6 months vs baseline p < 0.05). APmean was 1.43 +/- 0.46 cm(2) at baseline, 1.82 +/- 0.45 cm(2) after 1 week and 1.94 +/- 0.35 cm(2) after 6 months (1 week vs baseline p < 0.01; 6 months vs baseline; p < 0.05). V,NEP(0.5) was 290 +/- 73 mL at baseline, 291 +/- 65 mL after 1 week and 338 +/- 67 mL after 6 months (6 months vs baseline p < 0.05; 1 week vs 6 months p < 0.01). Our data suggest that CPAP treatment might be effective in OSAH patients not only by causing a mechanical splint of UA but also by inducing an improvement on anatomical (early) and functional (later on) aspects of UA that can be observed during wakefulness.

Cost‐Effectiveness of Continuous Positive Airway Pressure Therapy in Patients with Obstructive Sleep Apnea‐Hypopnea in British Columbia

Obstructive sleep apnea-hypopnea (OSAH) is a common disorder characterized by recurrent collapse of the upper airway during sleep. Patients experience a reduced quality of life and an increased risk of motor vehicle crashes (MVCs). Continuous positive airway pressure (CPAP), which is the first-line therapy for OSAH, improves sleepiness, vigilance and quality of life. To assess the cost-effectiveness of CPAP therapy versus no treatment for OSAH patients who are drivers. A Markov decision analytical model with a five-year time horizon was used. The study population consisted of male and female patients, between 30 and 59 years of age, who were newly diagnosed with moderate to severe OSAH. The model evaluated the cost-effectiveness of CPAP therapy in reducing rates of MVCs and improving quality of life. Utility values were obtained from previously published studies. Rates of MVCs under the CPAP and no CPAP scenarios were calculated from Insurance Corporation of British Columbia data and a systematic review of published studies. MVCs, equipment and physician costs were obtained from the British Columbia Medical Association, published cost-of-illness studies and the price lists of established vendors of CPAP equipment in British Columbia. Findings were examined from the perspectives of a third-party payer and society. From the third-party payer perspective, CPAP therapy was more effective but more costly than no CPAP (incremental cost-effectiveness ratio [ICER] of $3,626 per quality-adjusted life year). From the societal perspective, the ICER was similar ($2,979 per quality-adjusted life year). The ICER was most dependent on preference elicitation method used to obtain utility values, varying almost sixfold under alternative assumptions from the base-case analysis. After considering costs and impact on quality of life, as well as the risk of MVCs in individuals with OSAH, CPAP therapy for OSAH patients is a highly efficient use of health care resources. Provincial governments who do not provide funding for CPAP therapy should reconsider.

Upper airway dynamics during negative expiratory pressure in apneic and non-apneic awake snorers

BackgroundThe ability of negative expiratory pressure (NEP) technique to differentiate between awake snorers with and without obstructive sleep apnea-hypopnea (OSAH) was investigated.MethodsForty-eight subjects with sleep disordered breathing (SDB) and 7 healthy subjects, as non-snorer controls, underwent the NEP application of -5 and -7 cmH2O in the seated and supine position during wakefulness, after performing a sleep study. The upper airway collapsibility was assessed by computing the volume exhaled during the first 0.5 sec. (V,NEP0.5) and 1 sec. (V,NEP1) following the NEP start.ResultsPatients with severe (AHI ≥ 30) (n = 19) and mild-to-moderate (AHI <30 and >5) (n = 15) OSAH had lower V,NEP0.5 (340 ± 88 ml) as compared to snorers (AHI ≤ 5) (n = 14) (427 ± 101 ml; p < 0.01) and controls (n = 7) (492 ± 69 ml; p < 0.001) in the supine position with NEP -5 cmH2O. Less significant differences among the different groups were observed for V,NEP0.5 in the seated position with NEP -5 cmH2O and in both positions with NEP -7 cmH2O (only OSAH patients vs controls, p < 0.001). Similar results were obtained for V,NEP1 in either position by using both NEP -5 cmH2O and -7 cmH2O. In spite of this, a substantial overlapping of V,NEP0.5 and V,NEP1 between snorers and OSAH patients did not allow to identify a reliable diagnostic cut-off level. An inverse correlation with AHI was found for V,NEP0.5 in the supine position with NEP -5 cmH2O (rs = -0.46, p < 0.05) in severe OSAH patients.ConclusionThe awake OSAH patients exhibit values of V,NEP0.5 and V,NEP1 lesser than those of awake snorers. The NEP technique, however, appears to have a limited usefulness as clinical tool for routine screening of the OSAH patients during wakefulness.

A randomized trial of auto-titrating CPAP and fixed CPAP in the treatment of obstructive sleep Apnea–Hypopnea

Background: Continuous positive airway pressure (CPAP) remains the treatment of choice for obstructive sleep apnea–hypopnea (OSAH). Auto-titrating CPAP (APAP) devices automatically adjust pressure and may improve treatment compliance compared to fixed CPAP (F-CPAP). Methods: Randomized, prospective, single-blind, crossover trial to compare efficacy, side effects, compliance, patient satisfaction and preference between APAP and F-CPAP therapy in patients with moderate to severe OSAH. There were two treatment periods of 4 weeks each (APAP and F-CPAP), separated by a 2-week washout period. Results: Ten CPAP-naı̈ve OSAH patients (9 males) completed the study. They had Mean ± sd age of 44.9±9.7 years; body mass index of 35.9±12.9 kg/m 2 and apnea/hypopnea index (AHI) of 47.2±35.6. Both forms of therapy were equally effective in improving the symptoms and in reducing the AHI. Both forms of therapy were associated with frequent side effects and had similar patient compliance. At the end of the study, more patients (6–1) preferred F-CPAP to A-CPAP therapy. Conclusion: A-PAP was as effective as F-CPAP in the treatment of OSAH but was not associated with fewer side effects, better compliance, better satisfaction or increased patient preference.