Adherence to CPAP therapy for sleep apnea in patients aged over 70 years old.

PURPOSE: Adherence to continuous positive airway pressure (CPAP) for obstructive sleep apnea (OSA) syndrome has not been established in patients over 70 years of age, whereas several studies have reported adherence below that age. This trial was designed to address this evidence gap. METHODS: Consecutive senior (> 70 years) patients with OSA, mean respiratory event index (REI) 34/h, body mass index (BMI) 31 kg/m2, and junior (< 50 years) patients (REI 37/h, BMI 31 kg/m2) were included. RESULTS: At year follow-up among 72 senior patients (35 women) and 71 junior patients (17 women), there was no difference in the percentage of patients abandoning CPAP (senior 47% vs. junior 43%) or in CPAP daily use (4:53 ± 2:44 hh:min vs. 4:23 ± 3:00 hh:min). CONCLUSIONS: CPAP adherence in senior patients with OSA was not poorer than that of a younger group of OSA patients. Advanced age should not be an obstacle to CPAP initiation.

Genetic analysis of obstructive sleep apnoea discovers a strong association with cardiometabolic health.

There is currently limited understanding of the genetic aetiology of obstructive sleep apnoea (OSA). We aimed to identify genetic loci associated with OSA risk, and to test if OSA and its comorbidities share a common genetic background.We conducted the first large-scale genome-wide association study of OSA using the FinnGen study (217 955 individuals) with 16 761 OSA patients identified using nationwide health registries.We estimated 0.08 (95% CI 0.06-0.11) heritability and identified five loci associated with OSA (p<5.0×10-8): rs4837016 near GAPVD1 (GTPase activating protein and VPS9 domains 1), rs10928560 near CXCR4 (C-X-C motif chemokine receptor type 4), rs185932673 near CAMK1D (calcium/calmodulin-dependent protein kinase ID) and rs9937053 near FTO (fat mass and obesity-associated protein; a variant previously associated with body mass index (BMI)). In a BMI-adjusted analysis, an association was observed for rs10507084 near RMST/NEDD1 (rhabdomyosarcoma 2 associated transcript/NEDD1 γ-tubulin ring complex targeting factor). We found high genetic correlations between OSA and BMI (rg=0.72 (95% CI 0.62-0.83)), and with comorbidities including hypertension, type 2 diabetes, coronary heart disease, stroke, depression, hypothyroidism, asthma and inflammatory rheumatic disease (rg>0.30). The polygenic risk score for BMI showed 1.98-fold increased OSA risk between the highest and the lowest quintile, and Mendelian randomisation supported a causal relationship between BMI and OSA.Our findings support the causal link between obesity and OSA, and the joint genetic basis between OSA and comorbidities.

Positive airway pressure therapy for obstructive sleep apnea in patients with Osteogenesis imperfecta: a prospective pilot study.

BACKGROUND: Obstructive sleep apnea (OSA) is prevalent in individuals with Osteogenesis imperfecta (OI). To date, no study has investigated treatment of OSA in adult individuals with OI using positive airway pressure (PAP). This observational pilot study examined the adherence of adults with OI to treatment of OSA with PAP therapy, and the evolution of self-experienced sleepiness and depression symptoms before and after treatment. METHODS: We included 20 patients, with a mean age of 51 years, who represented varying severity of OI and displayed an apnea and hypopnea index ≥ 5 /sleeping hour as recorded by an overnight polysomnography. PAP therapy was proposed to all patients. Epworth Sleepiness Scale (ESS) questionnaire to evaluate daytime sleepiness, and a validated self-rating depression questionnaire to identify possible depression, were completed prior to PAP therapy and repeated after a minimum of one year. The datasets supporting the conclusions of this article are included within the article. RESULTS: From the 20 patients, 15 initiated PAP therapy, and two patients later interrupted it. The mean PAP follow-up period was 1230 days. At baseline, an abnormally high ESS score was reported by 29% of the respondents, and an abnormally high number of symptoms suggesting depression by 29%. Follow-up questionnaires were completed by 60% of the patients, of whom 83% were adherent to PAP treatment. ESS score and depression symptoms did not decrease significantly with PAP therapy. CONCLUSIONS: Patients with OI accepted well PAP therapy and remained compliant. Sleepiness and depression persisted unaltered despite good PAP adherence. These unexpectedly poor improvements in symptoms by PAP therapy may be due to subjective depression symptoms and the complexity of factors underlying persisting sleepiness in OI. Further research is needed to confirm this novel finding.

A detection dog for obstructive sleep apnea: could it work in diagnostics?

PURPOSE: We have previously demonstrated that dogs can be trained to distinguish the urine of patients with obstructive sleep apnea (OSA) from that of healthy controls based on olfaction. Encouraged by these promising results, we wanted to investigate if a detection dog could work as a screening tool for OSA. The objective of this study was to prospectively assess the dogs' ability to identify sleep apnea in patients with OSA suspicion. METHODS: Urine samples were collected from 50 patients suspected of having OSA. The urine sample was classified as positive for OSA when the patient had a respiratory event index of 5/h or more. The accuracy of two trained dogs in identifying OSA was tested in a prospective blinded setting. RESULTS: Both of the dogs correctly detected approximately half of the positive and negative samples. There were no statistically significant differences in the dogs' ability to recognize more severe cases of OSA, as compared to milder cases. CONCLUSION: According to our study, dogs cannot be used to screen for OSA in clinical settings, most likely due to the heterogenic nature of OSA.

A detection dog for obstructive sleep apnea.

PURPOSE: We sought to assess whether a dog can be trained to distinguish obstructive sleep apnea patients from healthy controls based on the olfactory detection of urine. METHODS: Urine samples were collected from 23 adult male obstructive sleep apnea patients and from 20 voluntary adult male volunteers. Three dogs were trained through reinforced operant conditioning. RESULTS: Two of the three dogs correctly detected two thirds of obstructive sleep apnea patients (p < 0.000194 and p < 0.000003, respectively). CONCLUSIONS: We found that dogs can be trained to distinguish obstructive sleep apnea patients from healthy controls based on the smell of urine. Potentially, dogs could be utilized to identify novel biomarkers or possibly screen for obstructive sleep apnea.

The Effect of mandible advancement splints in mild, moderate, and severe obstructive sleep apnea-the need for sleep registrations during follow up.

OBJECTIVE AND DESIGN: Our aim was to evaluate the effect of mandible advancement splint (MAS) in mild, moderate, and severe obstructive sleep apnea (OSA). We also determined, if and in which OSA-groups the adequate forward movement in MAS could be quantified without sleep registration for different OSA levels. A retrospective study. SETTINGS: The effect of MAS was measured with clinical methods and by sleep registration. PARTICIPANTS: The series consisted of 103 patients, 75 males and 28 females (mean age 52 years) suffering from mild (32 per cent), moderate (32 per cent), or severe (36 per cent) OSA, who were treated with MAS at Helsinki University Hospital, Finland during the years 2011-2012. Seventy per cent of the patients had tried continuous positive airway pressure (CPAP) before MAS. RESULTS: The lower the body mass index (BMI) was the bigger the probability was to get apnea/hypopnea index (AHI) values <5 per hour with MAS (P < 0.01). The total AHI decreased significantly from the baseline with MAS: 23 per hour (range 5-89) to 6 per hour (range 0.3-54), (P < 0.001). The mean oxygen desaturation index (ODI4%) improved significantly from 16 per hour (range 1-76) to 5.3 per hour (range 0.2-49), (P < 0.01), and the minimum oxygen saturation improved significantly from 84 per cent (67-91) to 87 per cent (68-93), (P < 0.01). The reduction of AHI with MAS was significantly bigger in patients with a previous CPAP experience (73 per cent) than those who did not tried CPAP therapy. The positive correlation was found between the decrease in AHI and the increase of the protrusion in MAS. CONCLUSION: Both sleep recordings and subjective indicators demonstrated that MAS therapy was successful in OSA based on ESS, total AHI, ODI4%, and minimum oxygen saturation values. It seems useful to increase the protrusion at its maximal clinical tolerance. An experienced dentist could make therapeutically decision concerning the follow up of MAS efficacy regardless of the result of sleep study. We suggest that MAS is a valuable treatment alternative for CPAP. However, the previous use of CPAP with MAS as well as lower baseline BMI seem to have a positive correlation with the success of MAS therapy.

Rates of initial acceptance of PAP masks and outcomes of mask switching.

PURPOSE: Recently, we noticed a considerable development in alleviating problems related to positive airway pressure (PAP) masks. In this study, we report on the initial PAP mask acceptance rates and the effects of mask switching on mask-related symptoms. METHODS: We prospectively collected all cases of mask switching in our sleep unit for a period of 14 months. At the time of the study, we used ResMed™ CPAP devices and masks. Mask switching was defined as replacing a mask used for at least 1 day with another type of mask. Changing to a different size but keeping the same type of mask did not count as mask switching. Switching outcomes were considered failed if the initial problem persisted or reappeared during the year that followed switching. RESULTS: Our patient pool was 2768. We recorded 343 cases of mask switching among 267 patients. Of the 566 patients who began new PAP therapy, 108 (39 women) had switched masks, yielding an initial mask acceptance rate of 81 %. The reason for switching was poor-fit/uncomfortable mask in 39 %, leak-related in 30 %, outdated model in 25 %, and nasal stuffiness in 6 % of cases; mask switching resolved these problems in 61 %. Mask switching occurred significantly (p = 0.037) more often in women and in new PAP users. The odds ratio for abandoning PAP therapy within 1 year after mask switching was 7.2 times higher (interval 4.7-11.1) than not switching masks. CONCLUSION: The initial PAP mask acceptance rate was high. Patients who switched their masks are at greater risk for abandoning PAP therapy.

Long-term CPAP treatment improves asthma control in patients with asthma and obstructive sleep apnoea.

PURPOSE: Both asthma and obstructive sleep apnoea cause sleep disturbance, daytime sleepiness and diminished quality of life. Continuous positive airway pressure (CPAP) is efficient in reducing symptoms related to sleep apnoea. Here we report the impact of long-term use of CPAP on asthma symptoms. METHODS: A survey questionnaire was distributed to all of our obstructive sleep apnoea patients with CPAP therapy in 2013. We used the Finnish version of the Asthma Control Test™ (ACT) and a visual analogue scale (0 = no symptoms, 100 = severe asthma symptoms). Asthma was defined as self-reported physician-diagnosed disease and a special reimbursement for asthma medication by the Social Insurance Institution. RESULTS: We sent 2577 questionnaires and received 1586 answers (61 %). One hundred ninety-seven patients were asthmatics with a prevalence of asthma among CPAP users of 13 %. We studied 152 patients (58 females) whose CPAP therapy was initiated after starting asthma medication. Their mean (SD) age was 62 (10) years, duration of CPAP 5.7 (4.7) years and their CPAP daily use was 6.3 (2.4) h. Self-reported asthma severity decreased significantly from 48.3 (29.6) to 33.1 (27.4) (p < 0.001), and ACT score increased significantly from 15.35 (5.3) to 19.8 (4.6) (p < 0.001) without a significant change in the body mass index (BMI). The percentage of patients using rescue medication daily reduced from 36 to 8 % with CPAP (P < 0.001). CONCLUSIONS: We noticed a significant decrease in asthma symptoms with long-term use of CPAP in patients with both asthma and obstructive sleep apnoea.

Oral appliance in sleep apnea treatment: respiratory and clinical effects and long-term adherence.

PURPOSE: There is an increasing tendency to use oral appliance (OA) as an alternative treatment for sleep apnea. Here we report the long-term adherence and clinical effects of OA therapy. METHODS: All sleep apnea patients treated at the Department of Dentistry between the years 2006 and 2013 (n = 1208) were reviewed. A questionnaire about OA adherence, asthma symptoms (Asthma Control Test™, ACT), and general health was sent to all patients who continued OA therapy after the 1-month follow-up visit (n = 811). OA was adjusted to obtain at least 70 % of the maximal protrusion of the mandible. RESULTS: The response rate was 37.4 % (99 women, 204 men). The mean ± SD age and BMI were 58.7 ± 10.3 years and 27.3 ± 4.0 kg/m(2), respectively. During the mean follow-up period of 3.3 years, there was no significant variation in BMI. Forty-one patients abandoned OA therapy yielding an adherence rate of 86 %. Ninety-seven percent of patients used OA ≥4 h/day, and the mean daily use was 7.2 ± 1.1 h. The ACT score improved with OA use from 16.0 ± 5.9 to 20.1 ± 3.8 (p = 0.004), indicating better asthma control. The apnea and hypopnea index decreased significantly from 27 ± 19 at baseline to 10 ± 10 with OA therapy (p = 0.001). CONCLUSIONS: After a 1-month trial period, the long-term adherence to oral appliance was good. OA therapy decreased apneas and hypopneas significantly, and its long-term use was associated with an improvement in respiratory and asthma symptoms.

Electro-oculography-based detection of sleep-wake in sleep apnea patients.

INTRODUCTION: Recently, we have developed a simple method that uses two electro-oculography (EOG) electrodes for the automatic scoring of sleep-wake in normal subjects. In this study, we investigated the usefulness of this method on 284 consecutive patients referred for a suspicion of sleep apnea who underwent a polysomnography (PSG). METHOD: We applied the AASM 2007 scoring rules. A simple automatic sleep-wake classification algorithm based on 18-45 Hz beta power was applied to the calculated bipolar EOG channel and was compared to standard polysomnography. Epoch by epoch agreement was evaluated. RESULT: Eighteen patients were excluded due to poor EOG quality. One hundred fifty-eight males and 108 females were studied, their mean age was 48 (range 17-89) years, apnea-hypopnea index 13 (range 0-96) /h, BMI 29 (range 17-52) kg/m(2), and sleep efficiency 78 (range 0-98) %. The mean agreement in sleep-wake states between EOG and PSG was 85% and the Cohen's kappa was 0.56. Overall epoch-by-epoch agreement was 85%, and the Cohen's kappa was 0.57 with positive predictive value of 91% and negative predictive value of 65%. CONCLUSIONS: The EOG method can be applied to patients referred for suspicion of sleep apnea to indicate the sleep-wake state.

Willingness score obtained after a short CPAP trial predicts CPAP use at 1 year.

PURPOSE: To predict continuous positive airway pressure (CPAP) adherence at 1 year. METHODS: We followed consecutive OSA patients scheduled for CPAP initiation for 1 year. Patients completed a self-efficacy questionnaire (5 = low, 25 = high score) before CPAP initiation. After CPAP initiation, we enquired about patients' satisfaction in CPAP trial and their eagerness and willingness to continue CPAP therapy (0 = unsatisfied, uneager, or refused CPAP; 100 = satisfied, eager, or willing to continue CPAP treatment). RESULTS: Of the 580 patients we followed, 377 continued CPAP therapy beyond 1 year. A low willingness score (<50) was expressed by 77 patients but only 7 of them used CPAP >4 h daily at 1 year, yielding a specificity of 97 % in predicting CPAP failure. At 1 year, patients with a self-efficacy score >20, expressed prior to CPAP initiation, used CPAP more often than the patients with a score <20 (average use 4.4 ± 2.2 h vs. 3.7 ± 2.3 h, p<0.001). CONCLUSIONS: A low score of willingness to continue CPAP therapy after a short trial predicts CPAP failure and poor CPAP adherence at 1 year.

Genetic Analysis of Obstructive Sleep Apnea and Its Relationship with Severe COVID-19.

Rationale: Although patients with obstructive sleep apnea (OSA) have a higher risk for coronavirus disease (COVID-19) hospitalization, the causal relationship has remained unexplored. Objectives: To understand the causal relationship between OSA and COVID-19 by leveraging data from vaccination and electronic health records, genetic risk factors from genome-wide association studies, and Mendelian randomization. Methods: We elucidated genetic risk factors for OSA using FinnGen (total N = 377,277), performing genome-wide association. We used the associated variants as instruments for univariate and multivariate Mendelian randomization (MR) analyses and computed absolute risk reduction against COVID-19 hospitalization with or without vaccination. Results: We identified nine novel loci for OSA and replicated our findings in the Million Veteran Program. Furthermore, MR analysis showed that OSA was a causal risk factor for severe COVID-19 (P = 9.41 × 10-4). Probabilistic modeling showed that the strongest genetic risk factor for OSA at the FTO locus reflected a signal of higher body mass index (BMI), whereas BMI-independent association was seen with the earlier reported SLC9A4 locus and a MECOM locus, which is a transcriptional regulator with 210-fold enrichment in the Finnish population. Similarly, multivariate MR analysis showed that the causality for severe COVID-19 was driven by BMI (multivariate MR P = 5.97 × 10-6, ß = 0.47). Finally, vaccination reduced the risk for COVID-19 hospitalization more in the patients with OSA than in the non-OSA controls, with respective absolute risk reductions of 13.3% versus 6.3%. Conclusions: Our analysis identified novel genetic risk factors for OSA and showed that OSA is a causal risk factor for severe COVID-19. The effect is predominantly explained by higher BMI and suggests BMI-dependent effects at the level of individual variants and at the level of comorbid causality.

Screening of snoring with an MP3 recorder.

PURPOSE: Snoring patients seeking medical assistance represent a wide range of clinical and sleep study findings from nonsleepy nonapneic snoring to severe obstructive sleep apnea syndrome. The prevalence of snoring is high and it significantly impacts quality of life. Its objective diagnosis usually requires a sleep study. We developed a system to analyze snoring sounds with a Moving Picture Experts Group Layer-3 Audio (MP3) recorder device and present its value in the screening of snoring. METHODS: We recorded snoring sounds during in-lab polysomnography (PSG) in 200 consecutive patients referred for a suspicion of obstructive sleep apnea. Snoring was recorded during the PSG with two microphones: one attached to the throat and the other to the ceiling; an MP3 device was attached to the patient's collar. Snoring was confirmed when the MP3 acoustic signal exceeded twice the median value of the acoustic signal for the entire recording. Results of the MP3 snoring recording were compared to the snoring recordings from the PSG. RESULTS: MP3 recording proved technically successful for 87% of the patients. The Pearson correlation between PSG snoring and MP3 snoring was highly significant at 0.77 (p < 0.001). The MP3 recording device underestimated the snoring time by a mean ± SD of 32 ± 55 min. CONCLUSIONS: The recording of snoring with an MP3 device provides reliable information about the patient's snoring.

CPAP interface: satisfaction and side effects.

PURPOSE: This study aimed to evaluate the care receiver's satisfaction with the continuous positive airway pressure (CPAP) interfaces. METHODS: A questionnaire with visual analog scales was sent to all our CPAP patients (0 = absolutely unsatisfied, 100 = very satisfied). From the ResMed ResScan program, we obtained the CPAP daily use and air leak values. RESULTS: We received 730 answers (70 % of participants); females comprised 22 %. A total of 391 patients had ResMed interfaces, 227 had Respironics, 87 had Fisher & Paykel (F&P), and 25 patients had other interfaces. Interfaces were nasal for 79 %, nasal pillows for 9 %, oronasal for 9 %, and unidentified for 3 % of cases. The mean ± SD satisfaction rate was 68 ± 25. No statistically significant differences were found regarding the type or brand of interface, previous interface experience, or the age or gender of the patient. Users of ResMed interfaces had significantly (p < 0.01) fewer cases of disturbing leaks than did users of Respironics or F&P interfaces (60 vs. 70 and 72 %, respectively). The ResMed Ultra Mirage interface had the fewest cases of disturbing leaks. Values for the measured median leaks were a mean of 5.9 ± 7.2 l/min, and those for the maximum leaks were 39.3 ± 22.2 l/min with no differences between brands. The users of F&P interfaces experienced significantly (p < 0.01) more comfort and used the CPAP device significantly (p < 0.007) more than did users of ResMed or Respironics interfaces (88 % of cases vs. 65 and 57 % and 6.2 ± 2.6 vs. 5.3 ± 2.8 or 5.8 ± 2.8 h/day, respectively). CONCLUSIONS: The majority of patients consider the use of the CPAP interface disturbing even though the satisfaction rate is good with no differences between brands.

Predicting compliance for mandible advancement splint therapy in 96 obstructive sleep apnea patients.

The treatment of choice in obstructive sleep apnea (OSA) is continuous positive airway pressure (CPAP). Mandible advancement splint (MAS) offers an option for patients with mild or moderate OSA, who refuse or are unable to tolerate CPAP. The aim of the study was to find predictive factors in OSA for MAS therapy. The study group comprised 96 consecutive OSA patients who were sent for MAS therapy during 2008. Data were collected on the patients' general and dental condition, diagnosis, and treatment for OSA. Panoramic and cephalometric radiographs were analysed. The treatment compliance rate and problems with the use of the MAS were recorded. This rate was 57% and the significant affecting factors were protrusion of the mandible with MAS during the adaptation to the appliance as well as shorter maxillary and mandible lengths. The compliance of the MAS therapy was best in patients with short maxilla and mandible, which should be taken into consideration when planning MAS therapy for OSA patients. Finally, a sleep study should be part of the follow-up in this patient population.

Migraine may disturb sleep perception during sleep onset: a retrospective data analysis.

STUDY OBJECTIVES: As sleep latency is an important factor in the diagnosis of many disorders, it is important to know whether the patient's self-reported evaluation of sleep latency corresponds with an objectively measured evaluation. Some studies indicate that patients usually overestimate their sleep latency. We sought to determine how comorbidities affect the patient's ability to assess their sleep latency. METHODS: This was a retrospective study of 240 patients who had a polysomnography recorded at our sleep unit or at home in 2017-2020. Data on comorbidities were collected from hospital records. RESULTS: Mean objective sleep latency (29.5 minutes, standard deviation [SD] 35.5) was significantly lower than self-reported sleep (37.4 minutes, SD 41.6) (P < .001). The patients who overestimated their sleep latency had higher mean apnea-hypopnea index (18.8 events/h, SD 21.6, vs 13.4 events/h, SD 12.8; P = .04) and higher mean sleep efficiency (81.7%, SD 13.6%, vs 75.2%, SD 13.9%; P = .004) than those who underestimated their sleep latency. There were significantly more patients with migraine in the overestimation group than in the underestimation group (20/159 patients vs 3/81 patients; P = .035). This difference was not observed in patients with headache without migraine (P = 1.000). CONCLUSIONS: We hypothesize that migraine is markedly associated with overestimation of sleep latency. This overestimation was not observed in patients with other headache types. Further studies are needed to explore the relation between migraine and sleep onset misperception. CITATION: Rantanen O, Hollmen M, Bachour A. Migraine may disturb sleep perception during sleep onset: a retrospective data analysis. J Clin Sleep Med. 2022;18(9):2113-2117.

Changes in the societal burden caused by sleep apnoea in Finland from 1996 to 2018: A national registry study.

BACKGROUND: In the current century, sleep apnoea has become a significant public health problem due to the obesity epidemic. To increase awareness, improve diagnostics, and improve treatment, Finland implemented a national sleep apnoea programme from 2002 to 2010. Here, we present changes in the societal burden caused by sleep apnoea from 1996 to 2018. METHODS: National register data were collected from the Care Register for Health Care, Statistics Finland, the Social Insurance Institution of Finland, and the Finnish Centre for Pensions. Disease prevalence, use of healthcare and social services, and societal costs were estimated. FINDINGS: The number of sleep apnoea patients increased in secondary care from 8 600 in 1996 to 61 000 in 2018. There was a continuous increase in outpatient visits in secondary care from 9 700 in 1996 to 122 000 in 2018 (1 160%) and in primary care from 10 000 in 2015 to 29 000 in 2018 (190%). Accordingly, the cumulative annual number of days off work for sleep apnoea increased from 1 100 to 46 000. However, disability pensions for sleep apnoea decreased from 820 to 550 (33%) during the observation period. Societal costs per patient decreased over 50% during the observation period (€2 800 to €1 200). INTERPRETATION: The number of sleep apnoea patients in Finland increased remarkably during the observation period. To control this burden, diagnostic methods and treatment were revised and follow up was reorganised. Consequently, there was a significant decrease in societal costs per patient. The decrease in disability pensions suggests earlier diagnosis and improved treatment. The national sleep apnoea programme was one of the initiators for these improved outcomes. FUNDING: The Finnish Institute for Health and Welfare and the Hospital District of Helsinki and Uusimaa (HUH), Helsinki, Finland.

No changes in nocturnal respiration with hypoglossal neurostimulation therapy for obstructive sleep apnoea.

STUDY OBJECTIVES: We initiated Hypoglossal Neurostimulation therapy (HGNS) at the Helsinki University Hospital in late 2014. Here, we report our experience. METHODS: We included all 15 HGNS patients. All patients had previously failed both CPAP and oral appliance therapy for sleep apnoea. Overnight polysomnography parameters were analysed before and at 1.5 years with HGNS. RESULTS: Mean ± SD patient age was 53 ± 6 years; 2 women and 13 men were included. Mean ± SD efficient CPAP level was 11.4 ± 3.4 cm H2 O. Implantation technically succeeded in all patients. There were no significant changes of AHI and ODI4 after HGNS [median (quartile) 29.2/h (19.8-38.7) versus 30.1/h (15.6-52.6) and 15.0/h (5.9-20) versus 12.5/h (6.9-30.2) respectively]. CONCLUSION: We did not observe significant changes in AHI and ODI4 indices with HGNS therapy. Larger multicentre randomised controlled trials are necessary before wider international use of HGNS.

Evaluation of CPAP mask performance during 3 years of mask usage: time for reconsideration of renewal policies?

BACKGROUND: Continuous positive airway pressure (CPAP) mask renewal policies vary inside and between countries. There are no independent studies on the optimal mask renewal frequency. We aimed to evaluate CPAP mask function over time in a real-life clinical setting, and to compare the results against current renewal policies. METHODS: Daily performance data of 1846 CPAP masks (65% nasal, 22% nasal pillows, 12% oronasal) were recorded from 450 participants (68% male, mean age 59 years) with obstructive sleep apnoea. The unintentional leak, Apnoea-Hypopnoea Index (CPAP-AHI) and usage data were exported from the CPAP device. RESULTS: Of 656 324 nights of CPAP usage, the mean renewal time was 497 days (SD 327), mean leak 5.7 L/min (SD 8.1) and CPAP-AHI 3.8 events/h (SD 3.6). The difference in mean leak between one (5.2 L/min, SD 7.5), 12 (6.0 L/min, SD 10.2) and 24 months (5.8 L/min, SD 7.5) was minimal (p=0.59). Mean CPAP-AHI remained normal and unchanged in nasal masks and pillows up to 30 months, and was highest in oronasal masks. Different mask manufacturers performed similarly. Masks' daily or total usage did not affect the results. Shifting the mask renewal policy to 24 months could reduce the mask-related cost up to 50%-88%. CONCLUSIONS: Nasal masks and pillows could be used at least 2 years without significant changes in unintentional leak and CPAP-AHI. We suggest updating the mask renewal policies of nasal masks and pillows; results on oronasal masks and other manufacturers CPAP devices need further verification.