Randomised placebo controlled trial of daytime function after continuous positive airway pressure (CPAP) therapy for the sleep apnoea/hypopnoea syndrome The occurrence of sleep-disordered breathing among middle-aged adults. [Comparison of carbon dioxide rebreathing during application of continuous positive airway pressure with 3 types of nasal mask]. Comparison of therapeutic and subtherapeutic nasal continuous positive airway pressure for obstructive sleep apnoea: a randomised prospective parallel trial Nasal versus full face mask for noninvasive ventilation in chronic respiratory failure Automobile accidents in patients with sleep apnea syndrome. An epidemiological and mechanistic study. A prospective 8 week trial of nasal interfaces vs. a novel oral interface (Oracle) for treatment of obstructive sleep apnea hypopnea syndrome. Randomized placebo-controlled crossover trial of continuous positive airway pressure for mild sleep Apnea/Hypopnea syndrome. Effective compliance during the first 3 months of continuous positive airway pressure. A European prospective study of 121 patients. Oral continuous positive airway pressure for sleep apnea: effectiveness, patient preference, and adherence. A physiologic comparison of nasal and oral positive airway pressure. A randomized crossover efficacy trial of oral CPAP (Oracle) compared with nasal CPAP in the management of obstructive sleep apnea. Prospective study of the association between sleep-disordered breathing and hypertension. Clinical outcomes related to interface type in patients with obstructive sleep apnea/hypopnea syndrome who are using continuous positive airway pressure. CPAP therapy via oronasal mask for obstructive sleep apnea. Comparison of nose and face mask CPAP therapy for sleep apnoea
BACKGROUND Patients with the sleep apnoea/hypopnoea syndrome ( SAHS ) report improved sleepiness , cognitive function , and psychological well being after continuous positive airway pressure ( CPAP ) therapy , and it is for these daytime features that CPAP is usually given . However , few r and omised or controlled studies exist on the effects of CPAP on daytime function . METHODS A prospect i ve , r and omised , single blind , placebo controlled , crossover trial of daytime function after CPAP was conducted in 23 patients with SAHS , all with ⩾15 apnoeas+hypopnoeas/hour and ⩾2 symptoms of SAHS . All patients spent four weeks on CPAP therapy and four weeks on oral placebo treatment , following r and omisation to treatment order . With ethics committee approval , patients were told the placebo tablet might improve upper airway function . Average effective CPAP use was monitored using hidden time clocks . Assessment s of objective and subjective sleepiness , symptoms , cognitive performance , and psychological well being were performed on the last day of each treatment and compared . RESULTS Objective sleepiness measured by sleep onset latency on the multiple sleep latency test improved with CPAP ( mean difference from placebo + 2.4 min , 95 % CI 0.8 to 4.0 ; p<0.001 ) as did subjective sleepiness on the Epworth scale ( mean difference –6 , 95 % CI –3 to –9 ; p = 0.001 ) . Symptom total score also fell with CPAP ( mean difference –1.6 , 95 % CI –2.2 to –1.0 ; p<0.001 ) . No determinants of these changes with active treatment were identified , and no significant enhancements to cognitive function or psychosocial well being were found in this small sample . CONCLUSIONS These findings provide further evidence for clinical ly significant benefits to daytime function  from CPAP BACKGROUND Limited data have suggested that sleep-disordered breathing , a condition of repeated episodes of apnea and hypopnea during sleep , is prevalent among adults . Data from the Wisconsin Sleep Cohort Study , a longitudinal study of the natural history of cardiopulmonary disorders of sleep , were used to estimate the prevalence of undiagnosed sleep-disordered breathing among adults and address its importance to the public health . METHODS A r and om sample of 602 employed men and women 30 to 60 years old were studied by overnight polysomnography to determine the frequency of episodes of apnea and hypopnea per hour of sleep ( the apnea-hypopnea score ) . We measured the age- and sex-specific prevalence of sleep-disordered breathing in this group using three cutoff points for the apnea-hypopnea score ( > or = 5 , > or = 10 , and > or = 15 ) ; we used logistic regression to investigate risk factors . RESULTS The estimated prevalence of sleep-disordered breathing , defined as an apnea-hypopnea score of 5 or higher , was 9 percent for women and 24 percent for men . We estimated that 2 percent of women and 4 percent of men in the middle-aged work force meet the minimal diagnostic criteria for the sleep apnea syndrome ( an apnea-hypopnea score of 5 or higher and daytime hypersomnolence ) . Male sex and obesity were strongly associated with the presence of sleep-disordered breathing . Habitual snorers , both men and women , tended to have a higher prevalence of apnea-hypopnea scores of 15 or higher . CONCLUSIONS The prevalence of undiagnosed sleep-disordered breathing is high among men and is much higher than previously suspected among women . Undiagnosed sleep-disordered breathing is associated with daytime hypersomnolence A comparison is made between the end-tidal fractional concentration of carbon dioxide ( FETCO2 ) obtained during application of varying levels of continuous positive airway pressure ( CPAP ) with a prototype mask ( from Carburos Metálicos ) and FETCO2 obtained with 2 commonly used nasal masks ( Profile Lite and ComfortClassic from Respironics ) . The nasal FETCO2 was measured on 3 consecutive days in 11 healthy volunteers , 12 patients with severe obstructive sleep apnea-hypopnea syndrome , and 12 hypercapnic patients . A different mask was r and omly assigned on each day and the FETCO2 was measured after 3 minutes of CPAP at 4 , 5 , 6 , 8 , 10 , 15 , and 20 cm H2O . Although in all cases a progressive reduction in FETCO2 was observed with increasing CPAP , the effect was greatest with the prototype mask at all pressures . In the 3 different study groups the pressures obtained with the prototype mask were similar to those generated by the CPAP machine . In conclusion , the lower concentration of nasal CO2 obtained using the prototype mask suggests that it causes less rebreathing BACKGROUND Nasal continuous positive airway pressure ( NCPAP ) is widely used as a treatment for obstructive sleep apnoea . However , to date there are no r and omised controlled trials of this therapy against a well-matched control . We undertook a r and omised prospect i ve parallel trial of therapeutic NCPAP for obstructive sleep apnoea compared with a control group on subtherapeutic NCPAP . METHODS Men with obstructive sleep apnoea , defined as an Epworth sleepiness score of 10 or more and ten or more dips per h of more than 4 % SaO2 caused by obstructive sleep apnoea on overnight sleep study , were r and omly assigned therapeutic NCPAP or subtherapeutic NCPAP ( about 1 cm H2O ) for 1 month . Primary outcomes were subjective sleepiness ( Epworth sleepiness score ) , objective sleepiness ( maintenance of wakefulness test ) , and SF-36 question naire measurements of self-reported functioning and well-being . FINDINGS 107 men entered the study : 53 received subtherapeutic NCPAP and 54 therapeutic NCPAP . Use of NCPAP by the two treatment groups was similar : 5.4 h ( therapeutic ) and 4.6 h ( subtherapeutic ) per night . Subtherapeutic NCPAP did not alter the overnight number of SaO2 dips per h compared with baseline , and thus acted as a control . Therapeutic NCPAP was superior to subtherapeutic NCPAP in all primary outcome measures . The Epworth score was decreased from a median of 15.5 to 7.0 on therapeutic NCPAP , and from 15.0 to 13.0 on subtherapeutic NCPAP ( between treatments , p<0.0001 ) . Mean maintenance-of-wakefulness time increased from 22.5 to 32.9 min on therapeutic NCPAP and , not significantly , from 20.0 to 23.5 min on subtherapeutic NCPAP ( between treatments p<0.005 ) . Effect sizes for SF-36 measures of energy and vitality were 1.68 ( therapeutic ) and 0.97 ( subtherapeutic ) NCPAP ( between treatments p<0.0001 ) . For mental summary score , the corresponding values were 1.02 and 0.4 ( between treatments p=0.002 ) . INTERPRETATION Therapeutic NCPAP reduces excessive daytime sleepiness and improves self-reported health status compared with a subtherapeutic control . Compared with controls , the effects of therapeutic NCPAP are large and confirm previous uncontrolled clinical observations and the results of controlled trials that used an oral placebo This study was undertaken to determine the efficacy of nasal mask ( NM ) versus full face mask ( FFM ) for the delivery of noninvasive ventilation ( NIV ) in subjects with nocturnal hypoventilation . A total of 16 patients ( 11 males ) were enrolled , all with nocturnal hypoventilation currently treated at home with NIV via pressure preset devices . Subjects underwent full polysomnography on three occasions ; on the first night current therapy on NM was review ed , followed by two experimental studies in r and omised order using either NM or FFM . NIV setting s and oxygen flow rate were the same under both conditions . Notably , 14 of the 16 subjects required the use of a chinstrap to minimise oral leak . Apnoea-hypopnoea indices were within normal limits under both conditions ( 1.7±3.4 NM versus 1.6±2.4 h FFM ) . The type of interface did not significantly affect gas exchange during sleep ( minimum average arterial oxyhaemoglobin saturation total sleep time 93.4±2.1 NM versus 92.8±2.5 % FFM , Delta transcutaneous carbon dioxide nonrapid eye movement sleep to rapid eye movement sleep ( 0.58±0.36 NM versus 0.50±0.40 kPa FFM ) . Sleep efficiency was significantly reduced on the FFM ( 78±9 NM versus 70±14 % FFM ) , although arousal indices were comparable under both conditions ( 15.6±9.8 NM versus 15.8±8.8 h FFM ) . Full face masks appear to be as effective as nasal masks in the delivery of noninvasive ventilation to patients with nocturnal hypoventilation . However , a chinstrap was required to reduce oral leak in the majority of subjects using the nasal mask To investigate the association between sleep apnea syndrome ( SAS ) and automobile accidents , and to evaluate potential underlying mechanisms , we prospect ively recruited 60 consecutive patients with SAS ( apnea-hypopnea index , 58 + /- 3 h-1 ) and 60 healthy control subjects , matched for sex and age . The number of automobile accidents during the past 3 yr was obtained from participants and insurance companies . We quantified the degree of daytime sleepiness ( Epworth scale ) , anxiety and depression ( Beck tests ) , and we assessed the level of vigilance ( PVT 192 ) and driving performance ( Steer-Clear ) . Patients had more accidents than control subjects ( OR : 2.3 ; 95 % CI : 0.97 to 5.33 ) and were more likely to have had more than one accident ( OR : 5.2 ; 95 % CI : 1.07 to 25.29 , p < 0.05 ) . These differences persisted after stratification for km/yr , age , and alcohol consumption . Patients were more somnolent , anxious , and depressed than control subjects ( p < 0.01 ) , and they had a lower level of vigilance and poorer driving performance ( p < 0.01 ) . Yet , we did not find any correlation between the degree of daytime sleepiness , anxiety , depression , the number of respiratory events , nocturnal hypoxemia , level of vigilance , or driving simulator performance and the risk of automobile accidents among SAS patients . In conclusion , patients with SAS have an increased risk of automobile accidents . None of the clinical or physiological markers commonly used to define disease severity appear able to discriminate those patients at higher risk of having an automobile accident OBJECTIVE To compare efficacy , compliance rates , and side effects of a new strapless oral interface , the Oracle , with available nasal masks over 8 weeks of use for the treatment of obstructive sleep apnea hypopnea syndrome ( OSAHS ) . METHODS A total of 38 patients with OSAHS ( respiratory disturbance index ( RDI ) > /=15/h ) were enrolled after the diagnostic polysomnogram for subsequent continuous positive airway pressure ( CPAP ) therapy .  After r and omization , therapeutic pressures during a titration study were determined for 21 patients in the oral group and 17 patients in the nasal group . Comparisons for nasal and oral interfaces were made for baseline patient characteristics , average hours of CPAP use , side effects from therapy , and among question naires evaluating patients ' subjective responses to therapy at months 1 and 2 . RESULTS No significant difference was observed in the average hours of CPAP use between the oral ( 4.5+/-2.1 ; 5.5+/-2.6 ) and nasal groups ( 4.0+/-2.6 ; 4.8+/-2.5 ) for either month 1 or 2 ( P>0.05 ) . The dropout rates were similar for both groups after 8 weeks of therapy . However , patients in the nasal group had higher occurrences of side effects such as nasal congestion , dryness , and air leaks , whereas patients in the oral group experienced more oral dryness and gum pain . CONCLUSION Oral delivery of CPAP with the Oracle is an effective and suitable alternative for patients with OSAHS The minimal disease severity at which patients with the sleep apnea/hypopnea syndrome ( SAHS ) gain benefit from treatment is not well characterized , although a pilot study of continuous positive airway pressure ( CPAP ) therapy showed daytime improvements in patients with 5 to 15 apneas + hypopneas per hour slept ( AHI ) . We have thus performed a second , larger , r and omized , placebo- controlled study in a prospect i ve series of 34 patients ( 13 female ) with mild SAHS ( AHI 5 to 15 ) and daytime sleepiness . Patients spent 4 wk on CPAP treatment and 4 wk on an oral placebo , with r and omization of treatment order , and daytime assessment s on the last day of each treatment . Effective  CPAP  use averaged 2.8 + /- 2.1 h ( mean + /- SD ) per night . Compared with placebo , CPAP improved symptom score ( p < 0.01 ) , subjective ( Epworth ; p < 0.01 ) but not objective ( maintenance of wakefulness test ; p > 0.2 ) sleepiness , performances on 2 of 7 cognitive tasks ( p < 0.02 ) , depression score ( p < 0.01 ) , and five subscales of the SF-36 health/functional status question naire ( p < /= 0.03 ) . Fourteen of 34 patients preferred CPAP . In 14 patients with AHI in the range 5 to 10 , symptoms , cognitive function , psychological well-being and quality of life were improved . These results confirm benefits for daytime function after CPAP treatment for mild SAHS , but highlight unacceptability of CPAP in many such patients Effective compliance ( time spent at the effective pressure ) with nasal CPAP in obstructive sleep apnea has been reported to be poor . The aim of our study was to evaluate effective compliance in a large European multicenter study . One hundred twenty-one consecutive newly treated patients ( initial apnea-hypopnea index [ AHI ] = 62.0 + /- 29 . 5/h , AHI under CPAP = 6.4 + /- 8.1/h , CPAP pressure = 8.7 + /- 2.6 cm H(2)O , BMI = 33.1 + /- 6.8 kg/m(2 ) ) were r and omly allocated to a group with ( MC(+ ) ) ( n = 58 ) or without ( MC(- ) ) ( n = 63 ) a control unit measuring effective compliance at 1 , 2 , and 3 mo , which was compared with the built-in time counter data . MC(+ ) data were 94 + /- 10 , 98 + /- 5 , and 96 + /- 9 % of counter data at 1 , 2 , and 3 mo , respectively . Using criteria of regular use already reported in the literature ( at least 4 h of nCPAP per day of use and nCPAP administered more than 70 % of the days ) we found 77 , 82 , and 79 % compliant patients at 1 , 2 , and 3 mo , respectively , 79 % of the patients meeting these criteria each month . Although there were no pulmonary functions or polysomnographic differences between the two subgroups , the compliant patients did report a greater improvement in minor symptoms . We found a close correlation between effective use of CPAP and the machine run time . The main result of our study was a higher effective compliance than previously reported , approximately 80 % of the patients being regular users versus 46 % in a previously published study . This may result from different technical and medical follow-up BACKGROUND 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 . METHODS 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 . RESULTS 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 . CONCLUSIONS 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 can not rely exclusively on the nasal airway for CPAP therapy STUDY OBJECTIVES The effectiveness of nasal continuous positive airway pressure ( CPAP ) in treating obstructive sleep apnea ( OSA ) is based on raising the intramural pressure above a critical collapsing pressure of the oropharyngeal airway . It is currently unclear whether CPAP delivered orally is also capable of raising pressure in the oropharynx above the critical collapse pressure . DESIGN We tested a novel oral CPAP device to determine whether the pressure-flow relationships are similar to nasal CPAP and whether the device alters these relationships . Patients were selected based on having moderately severe apnea and were r and omized to nasal CPAP , nasal CPAP with oral device , or oral CPAP .  SETTING Johns Hopkins University , The Johns Hopkins Asthma and Allergy Center , Baltimore , MD . PATIENTS Five men and two women with OSA were studied . INTERVENTIONS Individual pressure-flow curves were constructed during the application of nasal or oral CPAP . RESULTS We found the following : ( 1 ) a similar effective pressure eliminated inspiratory flow limitation for the nasal or oral CPAP ; ( 2 ) as pressure in the nose or mouth was lowered below the effective pressure , a linear pressure-flow curve was obtained and a critical closing pressure was described ; ( 3 ) similar mean ( + /- SD ) critical pressures of -0.3 + /- 5.3 , 1.7 + /- 4.0 , and 0.5 + /- 2.8 cm H(2)O , respectively , occurred for nasal CPAP , nasal CPAP with the oral device in place , and oral CPAP conditions ( p > 0.1 ) ; and ( 4 ) the comparable mean values for upstream resistance were 27.8 + /- 19 , 19.1 + /- 8.3 , and 26.5 + /- 26.7 cm H(2)O/L/s , respectively , for the above three conditions ( p > 0.1 ) . CONCLUSIONS We concluded that comparable upper airway pressure-flow relationships were obtained during oral and nasal breathing . Moreover , effective treatment pressure is obtained when constant pressure is applied through either the nasal or oral route STUDY OBJECTIVES To determine the therapeutic efficacy and viability of a novel oral interface for continuous positive airway pressure ( CPAP ) compared with conventional nasal interfaces . DESIGN A r and omized single-blind crossover study . SETTING Hospital-based sleep laboratory . PATIENTS OR PARTICIPANTS 21 CPAP-naïve patients with obstructive sleep apnea ( baseline apnea-hypopnea index , 85 + /- 36 ) INTERVENTIONS : Nasal CPAP and oral CPAP MEASUREMENTS AND RESULTS : Patients were each treated for two 4-week periods using nasal CPAP and oral CPAP . The CPAP titrations were undertaken at the start of each treatment arm . Outcome measures were recorded at baseline and at the end of each treatment arm . These included polysomnography variables , CPAP compliance , subjective sleepiness , obstructive sleep apnea symptom ratings , and adverse effects . There were no significant differences between oral and nasal interfaces for the on-CPAP frequency of apneas and hypopneas ( mean difference , nasal-oral [ 95%CI ] = -4.6[-10.1 - 1.0]/h ; P = 0.06 ) or arousals ( -3.0 [-7.8 - 1.8]/h ; P = 0.23 ) . There were also no statistically significant differences between interfaces for scores on the Epworth Sleepiness Scale ( -0.7 [ -3.1 - 1.7 ] ; P = 0.20 ) , obstructive sleep apnea symptoms ( -7.7 [ -17.7 - 2.4 ] ; P = 0.052 ) , CPAP compliance ( 0.3 [ -0.5 - 1.1 ] h/night ; P = 0.50 ) , CPAP pressure ( 0.05 [ -0.66 - 0.76 ] cmH20 ; P = 0.73 ) , CPAP side effects scores ( -2.0 [ -5.3 - 1.4 ] ; P = 0.23 ) , or mask preference ( P = 0.407 ) . In addition , both nasal and oral interfaces significantly improved polysomnographic variables , Epworth Sleepiness Scale scores , obstructive sleep apnea symptoms , and CPAP compliance from baseline ( all P < 0.05 ) . CONCLUSIONS This preliminary study indicates that oral CPAP has similar efficacy to traditionally applied nasal CPAP in treating obstructive sleep apnea .  Additional large studies are required to determine the range of clinical situations where oral CPAP is indicated BACKGROUND Sleep-disordered breathing is prevalent in the general population and has been linked to chronically elevated blood pressure in cross-sectional epidemiologic studies . We performed a prospect i ve , population -based study of the association between objective ly measured sleep-disordered breathing and hypertension ( defined as a laboratory-measured blood pressure of at least 140/90 mm Hg or the use of antihypertensive medications ) . METHODS We analyzed data on sleep-disordered breathing , blood pressure , habitus , and health history at base line and after four years of follow-up in 709 participants of the Wisconsin Sleep Cohort Study ( and after eight years of follow-up in the case of 184 of these participants ) . Participants were assessed overnight by 18-channel polysomnography for sleep-disordered breathing , as defined by the apnea-hypopnea index ( the number of episodes of apnea and hypopnea per hour of sleep ) . The odds ratios for the presence of hypertension at the four-year follow-up study according to the apnea-hypopnea index at base line were estimated after adjustment for base-line hypertension status , body-mass index , neck and waist circumference , age , sex , and weekly use of alcohol and cigarettes . RESULTS Relative to the reference category of an apnea-hypopnea index of 0 events per hour at base line , the odds ratios for the presence of hypertension at follow-up were 1.42 ( 95 percent confidence interval , 1.13 to 1.78 ) with an apnea-hypopnea index of 0.1 to 4.9 events per hour at base line as compared with none , 2.03 ( 95 percent confidence interval , 1.29 to 3.17 ) with an apnea-hypopnea index of 5.0 to 14.9 events per hour , and 2.89 ( 95 percent confidence interval , 1.46 to 5.64 ) with an apnea-hypopnea index of 15.0 or more events per hour . CONCLUSIONS We found a dose-response association between sleep-disordered breathing at base line and the presence of hypertension four years later that was independent of known confounding factors . The findings suggest that sleep-disordered breathing is likely to be a risk factor for hypertension and consequent cardiovascular morbidity in the general population STUDY OBJECTIVES To evaluate the effect of interface on objective compliance , patient satisfaction , adverse effects , quality of life , and residual sleep-disordered breathing in patients with obstructive sleep apnea/hypopnea syndrome ( OSAHS ) using  continuous positive airway pressure ( CPAP ) . DESIGN R and omized , cross-over . SETTING Two suburban community-based hospital sleep laboratories . PATIENTS Data were collected on 39 patients with OSAHS ( mean age , 48.7 years ) , in whom CPAP was a novel treatment . INTERVENTIONS Interventions were nasal pillows ( Breeze ; Mallinckrodt Corporation ; Minneapolis , MN ) and nasal mask ( Contour ; Respironics ; Murrysville , PA ) . MEASUREMENTS AND RESULTS Outcomes assessed at the completion of each 3-week treatment period were objective compliance , adverse effects , and satisfaction with CPAP ( CPAP question naire ) , daytime sleepiness ( Epworth sleepiness scale [ ESS ] ) , quality of life ( Functional Outcomes of Sleep Question naire [ FOSQ ] ) , sleep diary , and residual sleep-disordered breathing ( apnea-hypopnea index [ AHI ] ) . Patients were r and omly assigned to use the nasal pillows or the nasal mask following laboratory titration and initiated on CPAP ( pressure range , 5 to 14 cm H(2)O ) . The percentage of days utilized favored the nasal pillows ( 94.1 % vs 85.7 % ; p = 0.02 ) , but minutes of use per night did not differ ( nasal pillows , 223 min ; nasal mask , 288 min ) . ESS scores were lower and the FOSQ total scores were higher following CPAP treatment ( p < 0.001 ) , but no differential treatment effects were noted . Fewer adverse effects , less trouble getting to sleep and staying asleep , and less air leak were reported with nasal pillows ( p < 0.04 ) . The mean + /- SD pretreatment AHI ( 47.1 + /- 35.1/h ) was significantly lower following treatment with CPAP for both types of interface ( nasal pillows , 10.2 + /- 9.8/h ; nasal mask , 7.0 + /- 7.7/h ; p < 0.001 ) . CONCLUSIONS Nasal pillows are a well-tolerated and effective interface for OSAHS patients receiving CPAP at < or = 14 cm H(2)O. Use of nasal pillows was associated with fewer adverse effects and better sleep quality during the first 3 weeks of CPAP therapy . Further investigation is needed to determine whether interface type affects long-term CPAP use STUDY OBJECTIVE To determine the effectiveness of oronasal masks for positive pressure therapy in alleviating  obstructive sleep apnea ( OSA ) .  METHODS AND PROCEDURES Polysomnographic records of all 245 patients with OSA who underwent therapeutic trials of either continuous positive airway pressure ( CPAP ) or bilevel positive airway pressure between January 1991 and December 1992 were review ed . Thirty patients who had been prescribed positive pressure therapy employing an oronasal mask were identified . Two patients known to be successfully treated with CPAP via oronasal mask underwent repeat polysomnography .  The initial portion of the study was a diagnostic evaluation during which the patients were untreated . During the second portion of the study , both patients used CPAP via an oronasal mask while wearing a mouthpiece design ed to maintain oral patency . RESULTS The 30 patients with OSA who were identified in this study had significant amelioration of OSA while receiving positive pressure therapy via oronasal mask compared with the baseline , diagnostic polysomnogram ( apnea index : 55.3 + /- 36.9 - ->1.6 + /- 3.7 , p < 0.001 ; hypopnea index : 21.2 + /- 20 - ->2.7 + /- 4.9 , p < 0.001 ; nadir of SaO2 : 72.5 + /- 13.9 - ->87.1 + /- 4.3 , p < 0.001 , mean + /- SD ) . Improvement of OSA did not depend on maintenance of a closed mouth , as evidence d by elimination of sleep-disordered breathing in the two patients receiving positive pressure via oronasal mask while wearing a mouthpiece to keep the mouth open . CONCLUSION Oronasal masks are a viable alternative interface for alleviating OSA with positive pressure therapy in those patients who are unwilling or unable to tolerate conventional nasal interfaces . Although there were no adverse consequences associated with the use of oronasal masks in our patients , appropriate safety pre caution s should be taken to minimize the possibility of aspiration of gastric contents and avoid untoward sequelae due to positive pressure device failure BACKGROUND Many patients with sleep apnoea/hypopnoea syndrome ( SAHS ) find nasal continuous positive airway pressure ( CPAP ) treatment unsatisfactory due to side effects related to mouth air leakage . A study was performed to compare side effects with face mask and nose mask CPAP therapy in patients with SAHS , with and without uvulopalatopharyngoplasty ( U3P ) . METHODS Twenty newly diagnosed patients with SAHS took part in a r and omised double limb trial of face or nose mask CPAP therapy ( four weeks per limb ) in which CPAP compliance in terms of machine run time was measured and patients answered a symptom question naire on side effects result ing from the mask . Ten patients with SAHS with U3P ( SAHS/U3P ) who were already regular users of nasal CPAP were also given a four week trial of face mask CPAP to compare compliance and symptoms . Ten patients with SAHS were matched with the 10 SAHS/U3P patients for body mass index , age , apnoea/hypopnoea index , and CPAP pressure . Long term compliance was estimated one year after the mask comparison studies . RESULTS For patients with SAHS  nightly compliance was higher with a nose mask ( mean ( SE ) 5.3 ( 0.4 ) hours/night CPAP ) than with a face mask ( 4.3 ( 0.5 ) hours/night CPAP ) , p = 0.01 ( mean difference 1.0 hour/night , 95 % CI 1.8 to 0.3 ) . Nose masks were rated more comfortable by 19 of 20 patients ( p<0.001 ) despite more mouth leak related symptoms . For SAHS/U3P patients compliance was marginally higher with nose masks ( 5.1 ( 0.7 ) hours/night CPAP ) than with face masks ( 4.0 ( 0.8 ) hours/night CPAP ) , p = 0.07 ( mean difference 1.1 hour/night , 95 % CI 2.1 to 0.1 ) . Nose masks were rated more comfortable by seven of 10 patients . There were no significant differences in side effect scores with face and nose masks . At one year nine of 10 SAHS patients and nine of 10 SAHS/U3P patients were still using CPAP . Compliance was 5.4 ( 0.6 ) hours/night for the SAHS patients and 3.5 ( 0.4 ) hours/night for the SAHS/U3P patients , p = 0.02 ( mean difference 1.9 hour/night , 95 % CI 3.6 to 0.3 ) . CONCLUSIONS Compliance is greater with nose mask CPAP than with face mask CPAP because the overall comfort is better and compensates for increased symptoms associated with mouth leakage . Improved face mask design is needed
BACKGROUND Continuous positive airway pressure ( CPAP ) is the mainstay of therapy for moderate to severe obstructive sleep apnoea ( OSA ) .
However , compliance with CPAP has been less than ideal .
There are many different CPAP interfaces now available for the treatment of OSA .
The type of CPAP delivery interface is likely to influence a patient 's acceptance of CPAP therapy and long term compliance .
OBJECTIVES This review aims to compare the efficacy of the various CPAP delivery interfaces available for the treatment of obstructive sleep apnoea .