Associations of fractional exhaled nitric oxide with airway dimension and mucus plugs on ultra-high-resolution computed tomography in former smokers and nonsmokers with asthma.

BACKGROUND: Associations of fractional exhaled nitric oxide (FeNO) with airway wall remodeling and mucus plugs remain to be explored in smokers and nonsmokers with asthma. Ultra-high-resolution computed tomography (U-HRCT), which allows accurate structural quantification of airways >1 mm in diameter, was used in this study to examine whether higher FeNO was associated with thicker walls of the 3rd to 6th generation airways and mucus plugging in patients with asthma. METHODS: The retrospective analyses included consecutive former smokers and nonsmokers with asthma who underwent U-HRCT in a hospital. The ratio of wall area to summed lumen and wall area was calculated as the wall area percent (WA%). Mucus plugging was visually scored. RESULTS: Ninety-seven patients with asthma (including 59 former smokers) were classified into low (<20 ppb), middle (20-35 ppb), and high (>35 ppb) FeNO groups (n = 24, 26, and 47). In analysis including all patients and subanalysis including nonsmokers or former smokers, WA% in the 6th generation airways was consistently higher in the high FeNO group than in the low FeNO group, whereas WA% in the 3rd to 5th generation airways was not. In multivariable models, WA% in the 6th generation airways and the rate of mucus plugging were higher in the high FeNO group than in the low FeNO group after adjusting for age, sex, body mass index, smoking status, lung volume, and allergic rhinitis presence. CONCLUSIONS: Higher FeNO may reflect the inflammation and remodeling of relatively peripheral airways in asthma in both former smokers and nonsmokers.

Evaluation of elevated plasma fatty acids as relevant factors for adult-onset asthma: The Nagahama Study.

BACKGROUND: Obesity and increased body mass index (BMI) are the known risk factors for adult-onset asthma. Serum free fatty acid (FFA) and other blood lipid levels are generally elevated in patients with obesity and may be involved in the onset of asthma. However, it remains largely unknown. This study aimed to elucidate the relationship between plasma fatty acids and new-onset asthma. METHODS: This community-based Nagahama Study in Japan enrolled 9804 residents. We conducted self-reporting questionnaires, lung function tests, and blood tests at baseline and 5 years later as follow-up. At the follow-up, plasma fatty acids were measured using gas chromatography-mass spectrometry. Body composition analysis was also measured at the follow-up. The associations between fatty acids and new-onset asthma were evaluated using a multifaceted approach, including targeted partial least squares discriminant analysis (PLS-DA). RESULTS: In PLS-DA for new-onset asthma, palmitoleic acid was identified as the fatty acid most associated with asthma onset. In the multivariable analysis, higher levels of FFA, palmitoleic acid, or oleic acid were significantly associated with new-onset asthma, independent of other confounding factors. The high body fat percentage itself was not the relevant factor, but showed a positive interaction with plasma palmitoleic acid for new-onset asthma. When stratified by gender, the impacts of higher levels of FFA or palmitoleic acid on new-onset asthma remained significant in females, but not in males. CONCLUSIONS: Elevated levels of plasma fatty acids, particularly palmitoleic acid, may be a relevant factor for new-onset asthma.

Increased blood eosinophils and airflow obstruction as new-onset asthma predictors in the elderly: The Nagahama study.

BACKGROUND: Asthma in the elderly needs more attention in an aging society. However, it is likely to remain underdiagnosed and undertreated. This study aimed to clarify clinical characteristics of new-onset asthma in the elderly, describing the prevalence, predictive factors, and comorbidities after asthma diagnosis of new-onset asthma in the elderly in the general population. METHODS: This community-based prospective cohort study enrolled 9804 generally healthy participants (30-74 years old) in Nagahama City, and conducted a follow-up assessment after 5 years. Elderly participants were those aged ≥65 years at baseline. Patients with new-onset asthma were defined as participants without asthma at baseline assessment and with asthma at the follow-up assessment. RESULTS: Among the 7948 participants analyzed in this study, 28 (1.4%) elderly and 130 (2.2%) non-elderly had new-onset asthma. Multiple logistic regression analysis revealed low forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) and high blood eosinophil counts at baseline as predicting factors for new-onset asthma in the elderly. Additionally, subsequent incidence of new-onset asthma was higher in elderly participants with both predictors (high blood eosinophil counts and low FEV1/FVC at baseline) than those with none or one of the predictors before asthma diagnosis. Lastly, elderly patients with new-onset asthma had more frequent comorbidity of moderate to severe sleep disordered breathing than those non-elderly. CONCLUSIONS: Eosinophilic inflammation and airflow obstruction may predict subsequent new-onset asthma after the age of 65 years. Revealing the characteristics of new-onset asthma in the elderly can aid in the prevention of underdiagnosed asthma.

Sleep disordered breathing and haemoglobin A1c levels within or over normal range and ageing or sex differences: the Nagahama study.

Recently an association between blood glucose dysregulation and sleep disruption was suggested. The association between sleep disordered breathing, most of which is due to obstructive sleep apnea (OSA) in the general population, and diabetic severity, as well as the impact of antidiabetic treatment, remains unclear. This study aimed to investigate these associations as well as age and sex differences. This cross-sectional study evaluated 7,680 community participants as the main cohort (population-based cohort). OSA was assessed by the 3% oxygen desaturation index from pulse oximetry, which was corrected for sleep duration obtained by wrist actigraphy. For arguing the limitations for using pulse oximetry, 597 hospitalised patients, who were assessed by the apnea-hypopnea index from attended polysomnography, were also evaluated as the validation cohort (hospital-based cohort). Moderate-to-severe OSA was more prevalent as haemoglobin A1c (HbA1c) levels increased (<5.6%/5.6%-<6.5%/6.5%-<7.5%/≥7.5%, respectively) in both cohorts (p < 0.001), but only in those without antidiabetic treatment. The HbA1c level was an independent factor for moderate-to-severe OSA (population-based cohort, odds ratio [OR] 1.26, 95% confidence interval [CI] 1.10-1.45; hospital-based cohort, OR 1.69, 95% CI 1.22-2.33, per 1% increase). These associations were more prominent in the middle-aged (aged <60 years) than in the elderly (aged ≥60 years) and in women than in men in both cohorts. The prevalence of moderate-to-severe OSA in patients with antidiabetic treatment in the hospital-based cohort was ≥75% regardless of HbA1c levels. In conclusion, an association between the prevalence of OSA and HbA1c level even within or over the normal range was found only in patients without antidiabetic treatment and was more prominent in the middle-aged and in women.

Nationwide survey of refractory asthma with bronchiectasis by inflammatory subtypes.

RATIONALE: Bronchiectasis and bronchiolitis are differential diagnoses of asthma; moreover, they are factors associated with worse asthma control. OBJECTIVE: We determined clinical courses of bronchiectasis/bronchiolitis-complicated asthma by inflammatory subtypes as well as factors affecting them. METHODS: We conducted a survey of refractory asthma with non-cystic fibrosis bronchiectasis/bronchiolitis in Japan. Cases were classified into three groups, based on the latest fractional exhaled NO (FeNO) level (32 ppb for the threshold) and blood eosinophil counts (320/µL for the threshold): high (type 2-high) or low (type 2-low) FeNO and eosinophil and high FeNO or eosinophil (type 2-intermediate). Clinical courses in groups and factors affecting them were analysed. RESULTS: In total, 216 cases from 81 facilities were reported, and 142 were stratified: 34, 40 and 68 into the type 2-high, -intermediate and -low groups, respectively. The frequency of bronchopneumonia and exacerbations requiring antibiotics and gram-negative bacteria detection rates were highest in the type 2-low group. Eighty-seven cases had paired latest and oldest available data of FeNO and eosinophil counts; they were analysed for inflammatory transition patterns. Among former type 2-high and -intermediate groups, 32% had recently transitioned to the -low group, to which relatively low FeNO in the past and oral corticosteroid use contributed. Lastly, in cases treated with moderate to high doses of inhaled corticosteroids, the frequencies of exacerbations requiring antibiotics were found to be higher in cases with more severe airway lesions and lower FeNO. CONCLUSIONS: Bronchiectasis/bronchiolitis-complicated refractory asthma is heterogeneous. In patients with sputum symptoms and low FeNO, airway colonisation of pathogenic bacteria and infectious episodes are common; thus, corticosteroids should be carefully used.

Gastroesophageal reflux disease is a risk factor for sputum production in the general population: the Nagahama study.

BACKGROUND: Chronic sputum production in the general population is historically associated with clinical indices including male sex and smoking history. However, its relationship with gastroesophageal reflux disease (GERD), which may prove an underlying factor in sputum production, is unclear. We aimed to clarify factors associated with sputum production in the general population in cross-sectional and longitudinal manners. METHODS: In the Nagahama study, a community-based cohort study, 9804 subjects were recruited between 2008 and 2010 (baseline assessment), 8293 of whom were followed from 2013 to 2015 (follow-up assessment). This study contained a self-completed questionnaire which included medical history, assessment of sputum production, and a frequency scale for symptoms of GERD. A Frequency Scale for Symptoms of Gastroesophageal Reflux Disease score of ≥ 8 was defined as GERD. In addition to the frequency of sputum production at each assessment, frequency of persistent sputum production defined as sputum production at both assessments was examined. RESULTS: Frequency of sputum production was 32.0% at baseline and 34.5% at follow-up. Multivariable analysis demonstrated that sputum production at baseline was significantly associated with GERD [odds ratio (OR), 1.92; 95% confidence interval (CI) 1.73-2.13] and post-nasal drip (PND) (OR, 2.40; 95% CI 2.15-2.68), independent of other known factors such as older age, male sex and smoking history. These associations between sputum production and GERD or PND were also observed at follow-up. In longitudinal analysis, 19.4% had persistent sputum production and 12.3% had transient sputum production, i.e., at baseline only. Multivariable analysis for risk of persistence of sputum production revealed that persistent sputum production was associated with GERD and PND, in addition to the known risk factors listed above. The proportion of subjects with GERD at both assessments was highest among subjects with persistent sputum production. CONCLUSIONS: Cross-sectional and longitudinal analysis demonstrated an association in the general population between sputum production and GERD, as well as PND, independent of known risk factors. The presence of GERD should be assessed in patients complaining of sputum production.

Role of serum periostin in severe obstructive sleep apnea with albuminuria: an observational study.

BACKGROUND: Periostin is a matricellular protein and is a useful marker in respiratory diseases. However, the roles of periostin in patients with obstructive sleep apnea (OSA) remain unclear. Several in vitro studies have suggested that mechanical stress, hypoxia, impaired metabolism, and kidney injury, which often accompany OSA, may upregulate the expression of periostin. Meanwhile, serum periostin level has been negatively associated with body mass index (BMI) in the general population. In this study, we hypothesized that a high level of serum periostin despite being overweight/obese may discriminate severe OSA or OSA with comorbidities from mild OSA with obesity alone. We aimed to clarify the roles of periostin in patients with OSA to assist in elucidating the heterogeneity of OSA with comorbidities. METHODS: Among patients diagnosed as OSA, we examined the associations between serum periostin levels and clinical indices, including the severity of OSA, BMI, and comorbidities, using a multifaceted approach. The serum periostin levels and clinical indices were assessed after 3 months of continuous positive airway pressure (CPAP) treatment. RESULTS: In 96 patients with OSA, serum periostin level was negatively correlated with BMI, albeit marginally, and tended to be higher in severe OSA than in others when adjusted for BMI. Cluster analysis identified four clusters, including two severe OSA clusters, one of which was characterized by high serum periostin levels and the presence of comorbidities, including albuminuria. In a comparative analysis of severe OSA cases (n = 53), the level of serum-free fatty acids and the frequency of albuminuria were higher in patients with high serum periostin level of ≥87 ng/mL, which was the highest quintile among all participants, than in those with low serum periostin levels (< 87 ng/mL, n = 41). In patients with severe OSA and high serum periostin levels, the levels of serum periostin and urinary albumin significantly decreased after 3 months of CPAP treatment. CONCLUSIONS: Elevated serum periostin in patients with OSA despite being overweight/obese may be an indicator of severe OSA with comorbidities, particularly albuminuria.

Correlation between eosinophil count, its genetic background and body mass index: The Nagahama Study.

BACKGROUND: Obesity affects the pathogenesis of various chronic diseases, including asthma. Research on correlations between obesity/BMI and eosinophilic inflammation in asthma has yielded contradictory results, which could be partly ascribed to the absence of epidemiological data on the correlations. We aimed to elucidate the correlations between blood eosinophil count, its genetic backgrounds, and BMI in the general population. METHODS: This community-based Nagahama study in Japan enrolled 9789 inhabitants. We conducted self-reporting questionnaires, lung function tests, and blood tests in the baseline and 5-year follow-up studies. A genome-wide association study (GWAS) was performed in 4650 subjects at the baseline and in 4206 of these at the follow-up to determine single-nucleotide polymorphisms for elevated blood eosinophil counts. We assessed the correlations between BMI and eosinophil counts using a multifaceted approach, including the cluster analysis. RESULTS: Eosinophil counts positively correlated with BMI, observed upon the interchange of an explanatory variable, except for subjects with the highest quartile of eosinophils (≥200/µL), in whom BMI negatively correlated with eosinophil counts. GWAS and human leukocyte antigen (HLA) imputation identified rs4713354 variant (MDC1 on chromosome 6p21) for elevated eosinophil counts, independent of BMI and IgE. Rs4713354 was accumulated in a cluster characterized by elevated eosinophil counts (mean, 498 ± 178/µL) but normal BMI. CONCLUSIONS: Epidemiologically, there may be a positive association between blood eosinophil counts and BMI in general, but there was a negative correlation in the population with high eosinophil counts. Factors other than BMI, particularly genetic backgrounds, may contribute to elevated eosinophil counts in such populations.

The prevalence and disease burden of severe eosinophilic asthma in Japan.

Background: There are limited data on the prevalence and burden of severe eosinophilic asthma (SEA) both in Japan and globally. This study aimed to assess the prevalence and burden of SEA in Japan. Methods: This study was a retrospective, observational cohort analysis using health records or health insurance claims from patients with severe asthma treated at Kyoto University Hospital. The primary outcome was the prevalence of SEA, defined as a baseline blood eosinophil count ≥300 cells/µL. Secondary outcomes included frequency and risk factors of asthma exacerbations, and asthma-related healthcare resource utilization and costs. Results: Overall, 217 patients with severe asthma were included; 160 (74%) had eosinophil assessments. Of these, 97cases (61%), 54cases (34%), and 33cases (21%) had a blood eosinophil count ≥150, ≥300, and ≥500 cells/µL, respectively. Proportion of SEA was 34%. Blood eosinophil count was not associated with a significantly increased frequency of exacerbations. In the eosinophilic group, lower % forced expiratory volume in 1 second and higher fractional exhaled nitric oxide were predictive risk factors, while the existence of exacerbation history was a predictive risk factor for asthma exacerbations in the non-eosinophilic group. Severe asthma management cost was estimated as ¥357,958/patient-year, and asthma exacerbations as ¥26,124/patient-year. Conclusions: Approximately, one-third of patients with severe asthma in Japan have SEA. While risk factors for exacerbations differed between SEA and severe non-eosinophilic asthma, both subgroups were associated with substantial disease and economic burden. From subgroup analysis, blood eosinophil counts could be an important consideration in severe asthma management.

Sensitization to Staphylococcus aureus enterotoxins in smokers with asthma.

BACKGROUND: Sensitization to Staphylococcus aureus enterotoxins (SEs) augments eosinophilic inflammation in asthma. Recent epidemiologic studies demonstrate that sensitization to SEs is increased in healthy smokers; however, there is no evidence on the association between sensitization to SEs and eosinophilic inflammation in smokers with asthma. OBJECTIVE: To clarify the role of SEs on clinical indexes, including eosinophilic inflammation and lung function in smokers with asthma. METHODS: The frequency of atopic sensitization to SEs was examined in adult patients with asthma. In current or ex-smokers with asthma, the association of sensitization to SEs with eosinophilic inflammation, airflow limitation, or treatment steps was determined. Clinical indexes were examined at the first visit, and treatment steps were assessed 6 months after enrollment. RESULTS: Overall, 23 current smokers, 40 ex-smokers, and 118 never smokers with asthma were enrolled. The frequency of sensitization to SEs, but not to other aeroallergens, was significantly higher in current, ex-, and never smokers, in decreasing order. In current or ex-smokers with asthma, patients with sensitization to SEs exhibited higher serum levels of total and specific IgE to aeroallergens, higher blood eosinophil counts, greater airflow limitation, and more severe disease 6 months later than those without sensitization to SE. A longer smoking abstinence period was associated with serum specific IgE levels to SEs, and 3 years was the best cutoff of abstinence period to predict the absence of sensitization to SEs. CONCLUSION: Sensitization to SEs is increased in smokers with asthma, and it may be a marker of eosinophilic inflammation and severe asthma in smokers with asthma. TRIAL REGISTRATION: umin.ac.jp Identifier: UMIN000007818.

Sleep Restfulness in Patients with Obstructive Sleep Apnea Undergoing Continuous Positive Airway Pressure Therapy.

Objective Sleep restfulness is closely associated with mortality. Thus, it is an important sleep-related symptom in the general population. However, it is rarely evaluated in patients with obstructive sleep apnea (OSA) syndrome. The present study examined the importance of sleep restfulness in patients with OSA receiving continuous positive airway pressure (CPAP) therapy. Materials and Methods We administered sleep-related questionnaires, which included items such as subjective sleep duration and sleep restfulness, to 775 patients with OSA receiving CPAP therapy. Sleep restfulness was rated using a 5-point Likert-type scale, with the score of 5 indicating restfulness. Good adherence to CPAP therapy was defined as the use of CPAP therapy for at least 4 h per night in 70% of nights. Results We excluded 105 patients with lacking data. Thus, 670 patients were finally examined. In total, 29 (4.3%), 124 (18.5%), 139 (20.8%), 235 (35.1%), and 143 (14.3%) patients answered restless (1), somewhat restless (2), neither (3), somewhat restful (4), and restful (5) respectively. A total of 467 (69.7%) patients had good adherence to CPAP therapy. Multivariate logistic regression analysis showed that sleep restfulness was independently and positively associated with subjective sleep duration (≥ 7 hours) and good adherence to CPAP therapy. Conclusion Sleep restfulness was associated with subjective sleep duration and good adherence to CPAP therapy in patients with OSA. Favorable outcomes are significantly correlated with good adherence to CPAP therapy. Thus, sleep restfulness can be an indicator of a subtype that has favorable outcomes in patients after CPAP therapy.

Sputum microbiota and inflammatory subtypes in asthma, COPD, and its overlap.

Background: Airway microbiota in asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO) remains unknown. Objective: This study with ACO-enriched population aimed to clarify airway microbiota in ACO and in mixed granulocytic inflammation, often detected in ACO and chronic airway diseases. Methods: This is an observational cross-sectional study. Patients with asthma with airflow limitation, ACO, and COPD were enrolled. Blood tests, pulmonary function, exhaled nitric oxide, and sputum tests were conducted. Sputum microbiota was evaluated using the 16S rRNA gene sequencing technique. Results: A total of 112 patients (13 asthma, 67 ACO, and 32 COPD) were examined. There were no significant differences in α-diversity among the 3 diseases. The relative abundances of phylum Bacteroidetes, class Bacteroidia, and genus Porphyromonas were associated with decreased eosinophilic inflammation, and were significantly lower in ACO than in COPD. In a comparison of sputum inflammatory subtypes, the proportion of Haemophilus was numerically highest in the mixed granulocytic subtype, followed by the neutrophilic subtype. Likewise, the proportion of Haemophilus was the highest in the intermediate-high (2%-8%) sputum eosinophil group and lowest in the severe (≥8%) eosinophil group. Clinically, Haemophilus proportion was associated with sputum symptoms. Finally, the proportion of Streptococcus was associated with higher blood eosinophil counts and most severe airflow limitation. Conclusions: Bacteroidia and Porphyromonas abundances in sputum are associated with the eosinophil-low phenotype, and ACO may be characterized by a decrease in these taxa. A mild elevation in sputum eosinophil does not preclude the presence of Haemophilus, which should be noted in the management of obstructive airway diseases.

Associations between Nocturnal Hypoxemia and Retinal Nerve Fiber Layer Thinning: The Nagahama Study.

Rationale: There have been meta-analyses that showed reduced retinal nerve fiber layer (RNFL) thickness, which is a surrogate marker of glaucoma, in patients with obstructive sleep apnea (OSA). However, the sample sizes in these reports were small (<300), and the mechanism of RNFL thinning in patients with OSA was not revealed.Objectives: To investigate the relationship of RNFL thickness with nocturnal hypoxemia or hypoxemic burden in a large-scale study.Methods: In this epidemiological study, 8,309 community residents were enrolled. The actigraphy-modified 3% oxygen desaturation index (acti-ODI3%) and cumulative percentage of sleep time with oxygen saturation <90% (acti-CT90) modified by objective sleep duration using actigraphy were measured. The hypoxemic burden is shown as acti-CT90. Circumpapillary RNFL thickness was determined using optical coherence tomography.Results: Multivariable logistic analysis models revealed that an increase in acti-CT90 was significantly associated with mean RNFL thinning after adjusting for several factors in participants without glaucoma diagnosed or treated previously (ß = -0.037; P = 0.009). There were significant differences in mean RNFL thickness among participants stratified according to acti-CT90 (>1.5 vs. ⩽1.5; P = 0.04). Although acti-ODI3% was significantly associated with acti-CT90 (ß = 0.72; P < 0.0001), acti-ODI3% was not significantly associated with mean RNFL thickness in the multivariable logistic analysis (ß = -0.011; P = 0.48). In addition, acti-CT90 was significantly associated with mean RNFL thickness both in the elderly (⩾60 yr; ß = -0.058; P = 0.002) and nonelderly (<60 yr; ß = -0.054; P = 0.007).Conclusions: Acti-CT90, but not acti-ODI3%, was associated with mean RNFL thinning in participants irrespective of age in the elderly or nonelderly. Further prospective studies are required to investigate whether the prevention of hypoxic burden, which was shown as acti-CT90 in this study, is favorable for RNFL thinning.

Phase II study of pemetrexed and erlotinib in pretreated nonsquamous, non-small-cell lung cancer patients without an EGFR mutation.

BACKGROUND: Preclinical data indicated that the combination of erlotinib and pemetrexed is synergistic when erlotinib is administered after pemetrexed. PATIENTS AND METHODS: This was a phase II study of pemetrexed and erlotinib in patients with pretreated advanced non-squamous non-small-cell lung cancer (NSCLC) with wild-type epidermal growth factor receptor (EGFR). Chemotherapy consisted of pemetrexed (500 mg/m(2)) on day 1 and erlotinib (150 mg/body) on days 2-15 every 3 weeks. The protocol treatment was repeated until disease progression or intolerable toxicities occurred. RESULTS: Seventeen patients were enrolled between January 2010 and January 2013, and 15 patients were evaluable for both safety and efficacy. The study was terminated due to slow patient accrual. There was 1 complete response. There was a partial response in 3 patients, stable disease in 4 and progressive disease in 7. The response rate was 27% and disease control rate was 53%. The median progression-free survival and overall survival were 2.5 months and 6.7 months, respectively. CONCLUSIONS: Statistical interpretation could not been made due to the early termination of the study. Further studies are needed to clarify the efficacy of this regimen in NSCLC patients without EGFR mutation (UMIN-CTR No. 0000024531).

The Effects of Changing Continuous Positive Airway Pressure Devices in Japanese Patients with Obstructive Sleep Apnea: A Case Series.

Objective The effects of continuous positive airway pressure (CPAP) devices on obstructive sleep apnea (OSA) in Japanese patients have not been reported. We assessed the effects of changing CPAP devices (from the Philips Respironics device to the ResMed device) on the control of OSA. Methods We retrospectively examined 13 patients with OSA who voluntarily changed from the Philips Respironics device to the ResMed device due to a Philips Respironics CPAP device recall. Data on the apnea-hypopnea index (AHI) were obtained from the CPAP devices for three months before and after changing the devices. Results The AHI obtained from the CPAP devices significantly decreased from 4.4 (3.1-10.7) events/h to 2.0 (0.8-3.6) events/h when patients changed devices (p=0.022). The AHI decreased to <5 events/h after changing devices in 4 patients, whereas it had been ≥5 events/h before changing devices in 6 patients. Conclusion Changing CPAP devices can decrease the AHI.

Good clinical response achieved by changing servo-ventilation devices in a patient with central sleep apnea: a case report.

Servo-ventilation (SV) was developed for treating central sleep apnea. To date, primarily SV devices manufactured by Philips Respironics and ResMed are used. However, the difference in reaction to sleep-disordered breathing events between bilevel positive airway pressure AutoSV devices from Philips and adaptive SV devices from ResMed in clinical settings is unknown. Herein, we describe a case of central sleep apnea in which sleep-disordered breathing events were successfully controlled and sleepiness, sleep quality, and tolerance of the device were improved by changing from the bilevel positive airway pressure AutoSV device from Philips to the adaptive SV device from ResMed. Changing the SV devices can be a clinical option to appropriately control sleep-disordered breathing events in patients receiving SV therapy who present with persistent sleep-disordered breathing. CITATION: Hamada S, Togawa J, Sunadome H, Nagasaki T, Hirai T, Sato S. Good clinical response achieved by changing servo-ventilation devices in a patient with central sleep apnea: a case report. J Clin Sleep Med. 2023;19(8):1557-1561.

Effects of using in-line bacterial filters with continuous positive airway pressure devices in patients with sleep disordered breathing.

In June 2021, Philips Respironics first advised the use of in-line bacterial filters in response to a recall of continuous positive airway pressure (CPAP) devices. However, the effects of using in-line filters with CPAP devices have not yet been examined in a clinical setting. Here, we retrospectively evaluated 160 patients with sleep-disordered breathing (SDB) who voluntarily used in-line bacterial filters. Patients' perceptions of CPAP pressure after using in-line filters were investigated via a verbal interview. Patients described CPAP pressure as very weak (13, 8.1%), somewhat weak (42, 26.2%), unchanged (103, 64.4%), or somewhat strong (2, 1.3%). Five of the thirteen patients (38.5%) who described CPAP pressure as very weak discontinued the use of in-line filters. The apnea-hypopnea index obtained from the CPAP devices did not change after using in-line filters (n = 129, p = 0.85). Hence, although in-line bacterial filters could change patients' perceptions of CPAP pressure, they did not influence SDB control.