Obstructive sleep apnea is common in patients with interstitial lung disease

Intermittent Versus Sustained Hypoxemia from Sleep-disordered Breathing: Outcomes in Patients with Chronic Lung Disease and High Altitude

In a variety of physiologic and pathologic states, people may experience both chronic sustained hypoxemia and intermittent hypoxemia ("combined" or "overlap" hypoxemia). In general, hypoxemia in such instances predicts a variety of maladaptive outcomes, including excess cardiovascular disease or mortality. However, hypoxemia may be one of the myriad phenotypic effects in such states, making it difficult to ascertain whether adverse outcomes are primarily driven by hypoxemia, and if so, whether these effects are due to intermittent versus sustained hypoxemia.

Untreated Obstructive Sleep Apnea in Interstitial Lung Disease and Impact on Interstitial Lung Disease Outcomes

Subjects with interstitial lung disease (ILD) often suffer from nocturnal cough, insomnia, and poor sleep quality. Subjects with ILD and obstructive sleep apnea (OSA) seem to have relatively mild symptoms from sleep fragmentation compared to subjects with only ILD. The overlap of ILD, OSA, and sleeping hypoxemia may be associated with poor outcome, even though there is no agreement on which sleep parameter is mostly associated with worsening ILD prognosis. Randomized controlled trials are needed to understand when positive airway pressure (PAP) treatment is required in subjects with ILD and OSA and the impact of PAP treatment on ILD progression.

Effects of Obstructive Sleep Apnea on Airway Immunity and Susceptibility to Respiratory Infections

Obstructive sleep apnea is a prevalent sleep disorder characterized by recurrent episodes of partial or complete upper airway collapse during sleep, leading to disrupted breathing patterns and intermittent hypoxia. OSA results in systemic inflammation but also directly affects the upper and lower airways leading to upregulation of inflammatory pathways and alterations of the local microbiome. These changes result in increased susceptibility to respiratory infections such as influenza, COVID-19, and bacterial pneumonia. This relationship is more complex and bidirectional in individuals with chronic lung disease such as chronic obstructive lung disease, interstitial lung disease and bronchiectasis.

Dyspnea and Quality of Life Improvements with Management of Comorbid Obstructive Sleep Apnea in Chronic Lung Disease

Obstructive sleep apnea (OSA) has emerged as a significant and prevalent comorbidity associated with chronic lung diseases, including chronic obstructive pulmonary disease, asthma, and interstitial lung diseases. These overlap syndromes are associated with worse patient-reported outcomes (sleep quality, quality of life measures, mental health) than each condition independently. Observational studies suggest that patients with overlap syndrome who are adherent to positive airway pressure therapy report improved quality of life, sleep quality, depression, and daytime symptoms. Screening for and management of OSA in patients with overlap syndrome should emphasize the interconnected nature of these 2 conditions and the positive impact that OSA management can have on patients' well-being and overall health.

Obstructive Sleep Apnea and Sarcoidosis Interactions

Obstructive sleep apnea (OSA) is very prevalent in sarcoidosis patients. Sarcoidosis of the upper respiratory tract may affect upper airway patency and increase the risk of OSA. Weight gain due to steroid use, upper airway myopathy due to steroids and sarcoidosis itself, and interstitial lung disease with decreased upper airway patency are other reasons for the higher OSA prevalence seen in sarcoidosis. Several clinical manifestations such as fatigue, hypersomnolence, cognitive deficits, and pulmonary hypertension are common to both OSA and sarcoidosis. Therefore, early screening and treatment for OSA can improve symptoms and overall patient quality of life.

Co-existence of OSA and respiratory diseases and the influence of gender

INTRODUCTION

Sleep-disordered breathing (SDB), especially obstructive sleep apnea (OSA), is commonly associated with respiratory diseases, such as COPD, asthma and interstitial lung disease.

AREAS COVERED

This narrative review aims to comprehensively synthesize the existing information on SDB in respiratory diseases, investigate the role of gender in this association, and highlight the importance of OSA management in improving sleep, quality of life, and disease prognosis in these specific patient populations.

EXPERT OPINION

Research indicates a synergistic link between OSA and chronic respiratory diseases, which leads to greater morbidity and mortality compared to each disorder alone. Given the lack of an optimal OSA screening tool for these patients, a comprehensive patient approach and overnight diagnostic sleep study are imperative. Despite the limited evidence available, it seems that gender has an impact on the prevalence, severity, and susceptibility of this coexistence. Recognizing the role of gender in the coexistence of OSA and other respiratory diseases can enhance everyday medical practice and enable clinicians to adopt a more personalized approach toward optimal screening and diagnosis of these patients.

Sleep parameters in patients with chronic hypersensitivity pneumonitis: a case-control study

OBJECTIVE

To compare patients with chronic hypersensitivity pneumonitis (cHP) and controls with normal spirometry in terms of their sleep characteristics, as well as to establish the prevalence of obstructive sleep apnea (OSA) and nocturnal hypoxemia. Secondary objectives were to identify factors associated with OSA and nocturnal hypoxemia; to correlate nocturnal hypoxemia with the apnea-hypopnea index (AHI) and lung function, as well as with resting SpO2, awake SpO2, and SpO2 during exercise; and to evaluate the discriminatory power of sleep questionnaires to predict OSA.

METHODS

A total of 40 patients with cHP (cases) were matched for sex, age, and BMI with 80 controls, the ratio of controls to cases therefore being = 2:1. The STOP-Bang questionnaire, the Epworth Sleepiness Scale (ESS), the Pittsburgh Sleep Quality Index, the Berlin questionnaire and the Neck circumference, obesity, Snoring, Age, and Sex (NoSAS) score were applied to all cases, and both groups underwent full-night polysomnography.

RESULTS

The patients with cHP had longer sleep latency, lower sleep efficiency, a lower AHI, a lower respiratory disturbance index, fewer central apneas, fewer mixed apneas, and fewer hypopneas than did the controls. The patients with cHP had significantly lower nocturnal SpO2 values, the percentage of total sleep time spent below an SpO2 of 90% being higher than in controls (median = 4.2; IQR, 0.4-32.1 vs. median = 1.0; IQR, 0.1-5.8; p = 0.01). There were no significant differences between cases with and without OSA regarding the STOP-Bang questionnaire, NoSAS, and ESS scores.

CONCLUSIONS

The prevalence of OSA in cHP patients (cases) was high, although not higher than that in controls with normal spirometry. In addition, cases had more hypoxemia during sleep than did controls. Our results suggest that sleep questionnaires do not have sufficient discriminatory power to identify OSA in cHP patients.

Sleep quality and clinical association with sleep disturbance in systemic sclerosis

BACKGROUND

Poor sleep quality is a common and potentially debilitating problem in systemic sclerosis (SSc). To date, no data clarifies the potential factors related to poor sleep quality and the clinical associations with sleep disturbance among Thais with SSc-mainly the diffuse cutaneous SSc (dcSSc) subset. We aimed to evaluate sleep quality and identify the clinical association with sleep disturbance among SSc patients.

METHODS

A cross-sectional study was conducted between May 2021 and September 2021. Adult SSc patients were enrolled at the Scleroderma Clinic, Khon Kaen University, Thailand. All patients had their neck circumference measured, underwent airway evaluation using the Mallampati classification, had sleep quality assessed using the Pittsburgh Sleep Quality Index (PSQI), and the Berlin and Patient Health Questionnaire-9 completed. In addition, the clinical association with poor sleep quality (or sleep disturbance) was investigated using the PSQI.

RESULTS

A total of 88 patients were enrolled. Forty-eight (54.6%) patients experienced poor sleep quality (95%CI 43.6-65.2). Digital ulcers and dyspepsia were associated with poor sleep quality as per a logistic regression (OR 10.73: 95%CI 1.09-106.15 and 4.60: 95%CI 1.01-20.89), respectively. Overall pain-evaluated using the visual analog scale (VAS)-was positively correlated with the PSQI score (Rho 0.2586; p = 0.02).

CONCLUSION

Around half of the SSc patients reported poor sleep quality, and the significantly associated factors were digital ulcers and dyspepsia. The PSQI scores positively correlated with overall pain as evaluated by VAS. With early assessment and treatment of digital ulcers, stomach symptoms, and pain control, sleep problems might be reduced among SSc patients.

Role of sleep questionnaires in predicting obstructive sleep apnea amongst interstitial lung diseases patients

Introduction

The co-existence of obstructive sleep apnea (OSA) and interstitial lung diseases (ILD) results in significant morbidity and mortality. So screening for OSA is important for its early diagnosis among ILD patients. The commonly used questionnaires for screening of OSA are Epworth sleep score (ESS) and STOP-BANG. However, the validity of these questionnaires among ILD patients is not well studied. The aim of this study was to assess the utility of these sleep questionnaires in detection of OSA among ILD patients.

Methods

It was a prospective observational study of one year in a tertiary chest centre in India. We enrolled 41 stable cases of ILD who were subjected to self-reported questionnaires (ESS, STOP-BANG, and Berlin questionnaire). The diagnosis of OSA was done by Level 1 polysomnography. The correlation analysis was done between the sleep questionnaires and AHI. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated for all the questionnaires. The cutoff values of STOPBANG and ESS questionnaire were calculated from the ROC analyses. P value of <0.05 was considered to be significant.

Results

OSA was diagnosed in 32 (78%) patients with mean AHI of 21.8 ± 17.6.The mean age was 54.8 ± 8.9 years with majority being female (78%) and mean body mass index (BMI) was 29.7 ± 6.4 kg/m2. The mean ESS and STOPBANG score were 9.2 ± 5.4 and 4.3 ± 1.8, respectively, and 41% patients showed high risk for OSA with Berlin questionnaire. The sensitivity for detection of OSA was highest (96.1%) with ESS and lowest with Berlin questionnaire (40.6%). The receiver operating characteristics (ROC) area under curve for ESS was 0.929 with optimum cutoff point of 4, sensitivity of 96.9%, and specificity of 55.6%, while ROC area under curve for STOPBANG was 0.918 with optimum cutoff point of 3, sensitivity of 81.2% and specificity of 88.9%.The combination of two questionnaires showed sensitivity of >90%. The sensitivity also increased with the increasing severity of OSA. AHI showed positive correlation with ESS (r = 0.618, P < 0.001) and STOPBANG (r = 0.770, P < 0.001).

Conclusion

The ESS and STOPBANG showed high sensitivity with positive correlation for prediction of OSA in ILD patients. These questionnaires can be used to prioritize the patients for polysomnography (PSG) among ILD patients with suspicion of OSA.

Obstructive Sleep Apnea and Longitudinal Changes in Interstitial Lung Imaging and Lung Function: The MESA Study

Rationale: Obstructive sleep apnea (OSA) has been hypothesized to be a risk factor in interstitial lung disease (ILD) and is associated with radiological markers that may represent the earlier stages of ILD. Prior studies have been limited by their cross-sectional design and potential confounding by body habitus. Objectives: To test the hypothesis that OSA severity is associated with more high-attenuation areas (HAAs) on computed tomography and worse lung function over time among older community-dwelling adults. Methods: We used data from participants in the MESA (Multi-Ethnic Study of Atherosclerosis) who had apnea-hypopnea index (AHI) measured from polysomnography (2010-2013), high attenuation areas (HAAs, -600 to -250 Hounsfield units, n = 784), assessments from exams 5 (2010-2012) and 6 (2016-2018) full-lung computed tomography scans, and spirometry assessments (n = 677). Linear mixed-effects models with random intercept were used to examine associations of OSA severity (i.e., AHI and hypoxic burden) with changes in HAAs, total lung volumes, and forced vital capacity (FVC) between exams 5 and 6. Potential confounders were adjusted for in the model, including age, sex, smoking history, height, and weight. Results: Among those with a higher AHI there were more men and a higher body mass index. Participants with AHI ⩾ 15 events/h and in the highest hypoxic burden quartile each had increases in HAAs of 11.30% (95% confidence interval [CI], 3.74-19.35%) and 9.85% (95% CI, 1.40-19.01%) per 10 years, respectively. There was a more rapid decline in total lung volumes imaged and FVC among those with AHI ⩾ 15 events/h of 220.2 ml (95% CI, 47.8-392.5 ml) and 3.63% (95% CI, 0.43-6.83%) per 10 years, respectively. Conclusions: A greater burden of hypoxia related to obstructive events during sleep was associated with increased lung densities over time and a more rapid decline in lung volumes regardless of body habitus. Our findings suggest OSA may be a contributing factor in the early stages of ILD.

Prognostic Significance of Obstructive Sleep Apnea in a Population of Subjects with Interstitial Lung Diseases

INTRODUCTION

Obstructive sleep apnea (OSA) is often observed in subjects with interstitial lung disease (ILD). It may have a negative impact on the course of ILD, but its prognostic significance in relation to other known indicators of poor outcome is unclear.

METHODS

After a detailed work-up, including overnight unattended type III polygraphy, all subjects newly diagnosed with ILDs referred to our clinics were followed-up for at least 1.5 years or until death or progression of disease [> 10% decline in forced vital capacity (FVC) below baseline]. We analyzed relationships between some prespecified variables of interest, including sleeping results, to establish parameters predictive of progressive course.

RESULTS

Our population consisted of 46 subjects (mean age 59.6 years; males 61%); 23.9% and 41% had idiopathic pulmonary fibrosis and ILD associated with systemic diseases, respectively. Mean baseline forced vital capacity and diffusion capacity of carbon monoxide were 83% and 57% of predicted, respectively. Mean (± SE) Apnea-Hypopnea Index (AHI) was 17 (± 3) events/h. AHI in the ranges 5-14.9, 15-29.9, and ≥ 30 was recorded in 14 (31%), 6 (13%), and 9 (20%) subjects, respectively. Mean distance covered in the 6-MWG walk test (6MWT) was 302 (± 19) m and 26 subjects (57%) showed exertional oxyhemoglobin desaturation. The median follow-up was about 18 months. Multivariate logistic regression analysis showed that exertional desaturation (HR 8.2; 1.8-36.5 95% CI; p = 0.006) and AHI ≥ 30, namely the threshold of severe OSA (HR 7.5; 1.8-30.6; p = 0.005), were the only independent variables related to progressive disease course.

CONCLUSION

We conclude that exertional desaturation and elevated AHI had independent negative prognostic significance in our ILD population.

A Review of a Recent Meta-Analysis Study on Obstructive Sleep Apnea

This paper summarizes a recent meta-analysis of various topics in obstructive sleep apnea (OSA). In addition to cardiovascular disease and neurocognitive dysfunction, a wide variety of diseases have been associated with OSA, and associations with cancer have also been reported. Although continuous positive airway pressure is a very effective treatment, the results have shown that it does not reduce the incidence of various complications. It has been reported that uvulopalatopharyngoplasty was effective, and robotic surgery for the tongue root and hypoglossal nerve stimulation were also effective. The effectiveness of various medications to reduce daytime sleepiness has also been demonstrated. Although exercise lowered the apnea-hypopnea index, it was not related to changes in body composition, and it was also reported that exercise combined with weight control were effective. Additionally, interesting and clinically meaningful meta-analysis results were summarized and presented.

The prevalence of obstructive sleep apnea in sarcoidosis and its impact on sleepiness, fatigue, and sleep-associated quality of life: a cross-sectional study with matched controls (the OSASA study)

STUDY OBJECTIVES

Patients with sarcoidosis experience fatigue and excessive daytime sleepiness (EDS). However, the underlying pathomechanism is unclear. Studies suggested undiagnosed obstructive sleep apnea (OSA) to be an important contributor, but reliable data on prevalence and impact of OSA in sarcoidosis are scarce.

METHODS

71 adult patients with sarcoidosis, 1-to-1 matched to 71 adult controls according to sex, age, and body mass index were included. Participants underwent structured interviews (including Epworth Sleepiness Scale [ESS], Fatigue Assessment Scale [FAS], and Functional Outcome of Sleep Questionnaire [FOSQ-30]) and level-3 respiratory polygraphy. OSA was defined as apnea-hypopnea index ≥ 5 events/h. Prevalence of OSA was assessed and possible risk factors for OSA in sarcoidosis were investigated.

RESULTS

Mild OSA (AHI ≥ 5 events/h) was prevalent in 32 (45%) sarcoidosis patients vs 22 (31%) controls (P = .040). Sarcoidosis patients presented higher ESS compared with matched controls (P = .037). FAS scores (median [quartile] of 21.5 [16, 27.5]) indicated fatigue in sarcoidosis patients. Patients with EDS (ESS ≥ 11) presented reduced FOSQ-30 results (median [quartile] of 16.7 [15.2, 17.8]). ESS, FAS, and FOSQ were not associated with AHI in sarcoidosis patients. Body mass index, sex, neck circumference, and NoSAS score were predictors for OSA in sarcoidosis.

CONCLUSIONS

The risk for mild OSA is 2.5-fold higher in sarcoidosis patients compared with matched controls. OSA seems not to be the reason for increased sleepiness or fatigue in sarcoidosis. Risk factors such as body mass index, sex, neck circumference, and NoSAS score can be used to screen for OSA in sarcoidosis patients.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: Obstructive Sleep Apnoea in Sarcoidosis (OSASA); URL: https://clinicaltrials.gov/ct2/history/NCT04156789?V_2=View; Identifier: NCT04156789.

CITATION

Roeder M, Sievi NA, Schneider A, et al. The prevalence of obstructive sleep apnea in sarcoidosis and its impact on sleepiness, fatigue, and sleep-associated quality of life: a cross-sectional study with matched controls (the OSASA study). J Clin Sleep Med. 2022;18(10):2415-2422.

Overlaps between obstructive sleep apnoea and other respiratory diseases, including COPD, asthma and interstitial lung disease

In the past, there was limited research relating to the role of sleep in respiratory diseases. Physicians treating these patients tended to focus mainly on the daily disabling symptoms, overlooking the possible significant role of coexisting sleep disorders such as obstructive sleep apnoea (OSA). Nowadays, OSA has been recognised as an important, highly prevalent comorbidity for respiratory diseases such as COPD, asthma and interstitial lung diseases (ILDs). Overlap syndrome refers to the coexistence of chronic respiratory disease and OSA in the same patient. Although, in the past, overlap syndromes have been poorly studied, recent data underline that they result in increased morbidity and mortality compared with either underlying disorder alone. OSA and respiratory disease may be of different severity, and this, along with the existence of various clinical phenotypes, points to the necessity of an individualised therapeutic plan. Early recognition and OSA management could offer key benefits, such as improved sleep, quality of life and disease outcomes.

Educational aims

Describe pathophysiological aspects of OSA in chronic respiratory diseases such as COPD, asthma and ILDs.Understand the bidirectional clinical importance when OSA coexists in chronic respiratory diseases.Review current knowledge of treatment strategies towards an individualised therapeutic plan resulting in patient-centric outcomes.

The Association between Idiopathic Pulmonary Fibrosis and Obstructive Sleep Apnea: A Systematic Review and Meta-Analysis

The prevalence of obstructive sleep apnea (OSA) has greatly increased in recent years. Recent data suggest that severe and moderate forms of OSA affect between 6 and 17% of adults in the general population. Many papers are reporting the significantly increased prevalence of OSA in patients suffering from fibrotic diseases, including idiopathic pulmonary fibrosis (IPF). Therefore, we performed a systematic review and meta-analysis regarding the dependency between IPF and OSA. Due to the lack of papers focusing on IPF among OSA patients, we focused on the prevalence of OSA among IPF patients. In the search strategy, a total of 684 abstracts were identified, 496 after the removal of duplicates. After the screening of titles and abstracts, 31 studies were qualified for further full-text analysis for eligibility criteria. The final analysis was performed on 614 IPF patients from 18 studies, which met inclusion criteria. There were 469 (76.38%) IPF patients with OSA and 145 (23.62%) without. The mean age varied from 60.9 ± 8.1 up to 70.3 ± 7.9. The obtained prevalence was 76.4 (95% CI: 72.9–79.7) and 75.7 (95% CI: 70.1–80.9) for fixed and random effects, respectively. The median prevalence of OSA among non-IPF patients for all the ethnics groups included in this study was 16,4% (IQR: 3.4%–26.8%). The study provides strong evidence for the increased prevalence of OSA in IPF patients when comparing with the general OSA prevalence.

OSA and Chronic Respiratory Disease: Mechanisms and Epidemiology

Obstructive sleep apnea (OSA) is a highly prevalent disorder that has profound implications on the outcomes of patients with chronic lung disease. The hallmark of OSA is a collapse of the oropharynx resulting in a transient reduction in airflow, large intrathoracic pressure swings, and intermittent hypoxia and hypercapnia. The subsequent cytokine-mediated inflammatory cascade, coupled with tractional lung injury, damages the lungs and may worsen several conditions, including chronic obstructive pulmonary disease, asthma, interstitial lung disease, and pulmonary hypertension. Further complicating this is the sleep fragmentation and deterioration of sleep quality that occurs because of OSA, which can compound the fatigue and physical exhaustion often experienced by patients due to their chronic lung disease. For patients with many pulmonary disorders, the available evidence suggests that the prompt recognition and treatment of sleep-disordered breathing improves their quality of life and may also alter the course of their illness. However, more robust studies are needed to truly understand this relationship and the impacts of confounding comorbidities such as obesity and gastroesophageal reflux disease. Clinicians taking care of patients with chronic pulmonary disease should screen and treat patients for OSA, given the complex bidirectional relationship OSA has with chronic lung disease.

Respiratory diseases and obesity: special phenotype or independent events: Review

A combination of factors, including Western European eating habits, physical inactivity and genetic predisposition, lead to a dramatic increase in adipose tissue mass. A special place is occupied by abdominal obesity, in which there is an accumulation of adipose tissue in the mesentery of the small intestine and the omentum. Developing in conditions of visceral obesity, insulin resistance, dyslipidemia and systemic inflammation are one of the key components of the pathogenesis of type 2 diabetes mellitus, cardiovascular diseases, non-alcoholic fatty liver and pancreas disease, polycystic ovary disease, some forms of cancer (breast cancer, endometrial cancer, colonic and direct intestines). At the same time, the pathogenetic role of adipose tissue is not limited to its participation in the formation of the cardiometabolic continuum and oncogenesis. The most important role of metabolically active fat in the pathogenesis of many respiratory diseases is known, including bronchial asthma, obstructive sleep apnea and pulmonary hypertension. This paper presents an overview of current data on immunological, pathophysiological and clinical features of the phenotype of the combination of respiratory diseases with overweight and obesity.

Sleep disorders in elderly population suffering from TB and respiratory diseases

Sleep disorders (SD) are more frequent in the elderly population than younger counterparts. The underlying SD has a more severe impact on cardiorespiratory fitness. In elderly population with respiratory disorders, incidence and baneful influence of sleep disorders are extremely high. Insomnia in elderly is very common probably due to age related changes, underlying co morbidities and multiple medications. With aging there is decrease in duration of slow wave sleep and increase in NREM stage 1 and 2 sleep, which increases number of spontaneous arousals. Compared to younger people, elderly individuals tend to sleep earlier and wake up earlier due to changes in their normal circadian rhythm. Poor sleep quality and restless leg syndrome are higher in Tuberculosis patients. Disturbances in immune regulation due to chronic insomnia may exacerbate chronic infections like TB. Because many respiratory diseases and medications are known to cause sleep disturbances, it is important to assess treatable medical conditions and insomnia inducing medications before initiating hypnotics. Diagnosing sleep disordered breathing (SDB) in ILD patients is particularly important as nocturnal oxygen desaturation is associated with poor prognosis and could possibly be a cause of pulmonary hypertension. In patients with pulmonary hypertension (PH) and underlying obstructive sleep apnoea, CPAP therapy may help to reduce the PH. Addressing sleep disorders will be highly beneficial in elderly COPD patients with sleep disorders. This article reviews different SD, its effects and the treatment benefits in improving the quality of life and reducing the risk of progression of respiratory dysfunction in elderly population with TB and respiratory diseases.

Polysomnography findings and risk factors for sleep-disordered breathing in patients with systemic sclerosis

Objectives

This study aims to evaluate polysomnography findings and risk factors for sleep-disordered breathing in patients with systemic sclerosis (SSc).

Patients and methods

Thirty-nine patients (2 males, 37 females; mean age: 51.1±12.5 years; range, 21 to 76 years) who attended to the Rheumatology Clinic of Trakya University Medical Faculty between March 2014 and May 2014 were included in the study. Thoracic computed tomography, pulmonary function tests, carbon monoxide diffusion tests, echocardiography, and all-night polysomnography in a sleep laboratory were performed in all patients. Demographic and clinical characteristics of the patients were recorded. The Apnea-Hypopnea Index (AHI) scores were calculated. Disease activity was examined using the Medsger Disease Severity Scale (MDSS). Possible risk factors for sleep-disordered breathing were evaluated.

Results

Using the AHI of ≥5 for obstructive sleep apnea (OSA), 21 (53.8%) of the patients were classified as having OSA. There were no significant differences between the groups with and without OSA in terms of steroid use (p=0.4), CT involvement (p=0.3), and Warrick (p=0.6) and MDSS scores (p=0.5). Age, body mass index (BMI), and mean oxygen desaturation index were found to be significant in the univariate analysis (p<0.1); however, the multivariate analysis revealed only BMI as significant risk factor of OSA (p=0.028). In the multivariate analysis, the mean saturation was found to be significant risk factor for high pulmonary artery pressure (p<0.001).

Conclusion

Although OSA is common in SSc, only increased BMI is a significant risk factor of OSA, but not lung involvement, Warrick scores, or MDSS scores.

The frequency of obstructive sleep apnea in patients with primary Sjogren's syndrome

INTRODUCTION

There is a lack of information about the frequency of obstructive sleep apnea (OSA) in primary Sjogren's syndrome (pSS). Using all-night polysomnography (PSG), this study aimed to investigate the frequency of OSA in pSS and the factors affecting the frequency of OSA in this condition.  METHODS: Consecutive patients with pSS who presented to the Collagen Tissue Diseases follow-up polyclinic of the Department of Chest Diseases between 1 April 2019 and 31 December, 2020, were included in the study. Demographic characteristics, chronic diseases, smoking history in pack-years, anthropometric data, Epworth Sleepiness Scale score, pulmonary function test parameters, current thorax computed tomography findings, and PSG data were recorded. The control group was created by the retrospective screening of patients admitted to the sleep polyclinic and who underwent PSG but did not have pSS.

RESULTS

OSA was detected in 37 (84%) of 44 patients with pSS who underwent PSG. Of 37 patients with OSA, 25 (68%) had moderate or severe OSA. Snoring and witnessed apneas, REM%, snoring index, and maximum apnea and maximum hypopnea duration were statistically significantly lower in the pSS group compared with the control group (p < 0.001, p = 0.003, p = 0.025, p = 0.001, p = 0.028, and p = 0.035, respectively).

CONCLUSION

The frequency of OSA in patients with pSS was 84%, with a decrease in REM%. Although a correlation between symptoms suggesting OSA and the presence of radiological lung involvement, spirometry, and DLCO values with OSA could not be demonstrated, physicians are recommended to be attentive for the presence of OSA in all patients with pSS and to investigate OSA using PSG.

Patients with idiopathic pulmonary fibrosis with and without obstructive sleep apnea: differences in clinical characteristics, clinical outcomes, and the effect of PAP treatment

STUDY OBJECTIVES

Obstructive sleep apnea (OSA) in patients with idiopathic pulmonary fibrosis (IPF) is associated with worse mortality and clinical outcome. We aimed to assess differences between patients with IPF with and without OSA and the effect of positive airway pressure treatment on sleep and overall life quality, morbidity, and mortality in these patients.

METHODS

Forty-five patients with newly diagnosed IPF underwent polysomnography. Using an apnea-hypopnea index ≥ 15 events/h for OSA diagnosis resulted in 16 patients with IPF and 29 with IPF-OSA. The patients completed the Epworth Sleepiness Scale, Pittsburgh Sleep Quality Index, Functional Outcomes in Sleep Questionnaire, Fatigue Severity Scale, Short Form-36 life questionnaire, and Beck Depression Inventory before and at the end of the follow-up period.

RESULTS

Patients with IPF-OSA showed the most severe functional impairments in questionnaires, especially for General Health component of the Short Form-36 life questionnaire (37 vs 58, P = .03). At the 7-year follow-up, 16 (36%) patients had died, 6 (38%) in the IPF group and 10 (35%) in IPF-OSA group. Patients with ≥6-hour positive airway pressure use had better survival compared with patients with <6-hour use (P = .04). Significant improvement was also observed in Epworth Sleepiness Scale (3 vs 6, P = .03), Pittsburgh Sleep Quality Index (5 vs 8, P = .01), and Fatigue Severity Scale (37 vs 48, P = .008) score in patients with ≥4-hour positive airway pressure use.

CONCLUSIONS

OSA plays a significant role on clinical features and quality of life in patients with IPF. Effective positive airway pressure treatment results in a significant improvement in sleepiness, fatigue, sleep quality, and mortality.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: CPAP Therapy in Patients With Idiopathic Pulmonary Fibrosis and Sleep Apnea; URL: https://clinicaltrials.gov/ct2/show/record/NCT01637831; Identifier: NCT01637831.

Morbidity and mortality reduction associated with polysomnography testing in idiopathic pulmonary fibrosis: a population-based cohort study

Background

It is not well-known if diagnosing and treating sleep breathing disorders among individuals with idiopathic pulmonary fibrosis (IPF) improves health outcomes. We evaluated the association between receipt of laboratory-based polysomnography (which is the first step in the diagnosis and treatment of sleep breathing disorders in Ontario, Canada) and respiratory-related hospitalization and all-cause mortality among individuals with IPF.

Methods

We used a retrospective, population-based, cohort study design, analyzing health administrative data from Ontario, Canada, from 2007 to 2019. Individuals with IPF were identified using an algorithm based on health administrative codes previously developed by IPF experts. Propensity score matching was used to account for potential differences in 41 relevant covariates between individuals that underwent polysomnography (exposed) and individuals that did not undergo polysomnography (controls), in order minimize potential confounding. Respiratory-related hospitalization and all-cause mortality were evaluated up to 12 months after the index date.

Results

Out of 5044 individuals with IPF identified, 201 (4.0%) received polysomnography, and 189 (94.0%) were matched to an equal number of controls. Compared to controls, exposed individuals had significantly reduced rates of respiratory-related hospitalization (hazard ratio [HR] 0.43, 95% confidence interval [CI] 0.24–0.75), p = 0.003) and all-cause mortality (HR 0.49, 95% CI 0.30–0.80), p = 0.004). Significantly reduced rate of respiratory-related hospitalization (but not all-cause mortality) was also observed among those with >  = 1 respiratory-related hospitalization (HR 0.38, 95% CI 0.15–0.99) and systemic corticosteroid receipt (HR 0.37, 95% CI 0.19–0.94) in the year prior to the index date, which reflect sicker subgroups of persons.

Conclusions

Undergoing polysomnography was associated with significantly improved clinically-important health outcomes among individuals with IPF, highlighting the potential importance of incorporating this testing in IPF disease management.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01555-x.

Idiopathic pulmonary fibrosis cluster analysis highlights diagnostic delay and cardiovascular comorbidity association with outcome

Introduction

Idiopathic pulmonary fibrosis (IPF) prognosis is heterogeneous despite antifibrotic treatment. Cluster analysis has proven to be a useful tool in identifying interstitial lung disease phenotypes, which has yet to be performed in IPF. The aim of this study is to identify phenotypes of IPF with different prognoses and requirements.

Methods

Observational retrospective study including 136 IPF patients receiving antifibrotic treatment between 2012 and 2018. Six patients were excluded due to follow-up in other centres. Cluster analysis of 30 variables was performed using approximate singular value-based tensor decomposition method and comparative statistical analysis.

Results

The cluster analysis identified three different groups of patients according to disease behaviour and clinical features, including mortality, lung transplant and progression-free survival time after 3-year follow-up. Cluster 1 (n=60) was significantly associated (p=0.02) with higher mortality. Diagnostic delay was the most relevant characteristic of this cluster, as 48% of patients had ≥2 years from first respiratory symptoms to antifibrotic treatment initiation. Cluster 2 (n=22) had the longest progression-free survival time and was correlated to subclinical patients evaluated in the context of incidental findings or familial screening. Cluster 3 (n=48) showed the highest percentage of disease progression without cluster 1 mortality, with metabolic syndrome and cardiovascular comorbidities as the main characteristics.

Conclusion

This cluster analysis of IPF patients suggests that diagnostic and treatment delay are the most significant factors associated with mortality, while IPF progression was more related to metabolic syndrome and cardiovascular comorbidities.

Diagnostic delay and cardiovascular comorbidities impact IPF outcomeshttps://bit.ly/3lk2Z5y

Nocturnal hypoxaemia in interstitial lung disease: a systematic review

BACKGROUND

Patients with interstitial lung disease (ILD) are at risk of developing nocturnal hypoxaemia due to ventilatory restriction and impaired gas exchange that worsen with supine posture and reduced ventilatory drive during sleep. This systematic review synthesised literature on the diagnostic evaluation, epidemiology, associations, management and prognosis of nocturnal hypoxaemia in ILD.

METHODS

Ovid MEDLINE, Embase and CENTRAL databases were searched for eligible studies. Meta-analyses with subgroup analyses were conducted, where possible.

RESULTS

Fifty-three studies were included (total participant number=2590). The most common definition for clinically significant nocturnal hypoxaemia was ≥10% of total sleep time with oxyhaemoglobin saturation <90%, with pooled prevalence of 37%. There were no significant differences in pooled prevalence according to ILD subtype and comorbid obstructive sleep apnoea status. Study heterogeneity precluded meta-analysis of associations and prognosis. Diffusing capacity for carbon monoxide (DLCO) and echocardiographic features for pulmonary hypertension were consistently associated with nocturnal hypoxaemia. There were inconsistent associations between nocturnal hypoxaemia with ILD subtype and severity. Multivariable analyses in most studies demonstrated significant associations of nocturnal hypoxaemia with survival. Two small short-term intervention studies demonstrated that supplemental oxygen of 1-3 L/min corrected nocturnal hypoxaemia, with improved heart rate control during in-laboratory observation and increased serum antioxidant levels after 1 month of therapy.

CONCLUSION

Nocturnal hypoxaemia is common, associated with DLCO impairment and markers suggestive of pulmonary hypertension, and a potential prognostic factor in patients in ILD. There is a need to establish a consensus definition of nocturnal hypoxaemia and evaluate long-term effects of nocturnal supplemental oxygen in ILD.

Obstructive sleep apnea in pulmonary fibrosis

PURPOSE OF REVIEW

In previous years, there was limited research related to the role of sleep in interstitial lung diseases (ILDs). Physicians treating ILD patients tended to focus mainly on the daily disabling symptoms overlooking the possible significant role of coexisting sleep disorders, such as obstructive sleep apnea (OSA). However, recently, there has been a growing interest in OSA in ILDs, as well as OSA effect on sleep, life quality and outcome in these patients with emphasis on idiopathic pulmonary fibrosis (IPF).

RECENT FINDINGS

OSA has been recognized as an important, high-prevalence comorbidity for the diagnosis and management of IPF. This publication provides a summary of the most relevant recent evidence with regard to OSA in various ILDs and especially IPF, including prevalence, clinical presentation, complications, screening and diagnosis. It also provides updated evidence on the role of OSA therapy in improving sleep, quality of life and disease outcome.

SUMMARY

It is too early to characterize OSA and ILDs association as an 'overlap' syndrome. In depth research is needed, including studies with large numbers of ILDs and IPF patients. The main priority is to increase the awareness among physicians for early diagnosis of OSA in ILDs patients.

Prevalence and impact of comorbid obstructive sleep apnoea in diffuse parenchymal lung diseases

Objective

Obstructive sleep apnea (OSA) are increasingly recognized as important features in diffuse parenchymal lung diseases (DPLDs) with differed prevalence and impact reported. The aim of this study is to systematically review the prevalence of comorbid OSA and characterize its impact on clinical and outcome measurements in adults with DPLDs.

Methods

Publications addressing the prevalence of OSA in DPLDs and its impacts on DPLDs were selected from electronic databases. A random-effect model was used to estimate the pooled prevalence of OSA. Odds ratios (ORs) or mean differences (MDs) were used to assess the associations of OSA with clinical and outcome measurements. Heterogeneity was quantified by I² with 95% confidence interval (95% CI).

Results

4 studies comprising 643 participants were included. Overall, the pooled prevalence of OSA among DPLDs was 72% (95% CI: 65–79%; I² = 75.4%). Moderate-severe OSA was observed in 40% patients (95% CI: 28–52%; I² = 90.8%). The prevalence was higher as 76% in idiopathic pulmonary fibrosis (IPF) patients than in connective tissue associated-ILD or sarcoidosis (60%). Although oxygen desaturation during sleep was greater in OSA group compared with non-OSA patients, there was no difference in lung function or systematic comorbidities between the two groups. The associations between OSA and the mortality or disease progression of DPLDs were also systematically reviewed.

Conclusion

In conclusion, OSA is a common comorbidity in DPLD patients, affecting approximately three in four patients, which may exacerbate the nocturnal desaturation and have negative influence on the outcomes. Larger studies with more homogeneous samples are warranted.

Interstitial lung disease and obstructive sleep apnea

Obstructive sleep apnea (OSA) is one of the most common comorbidities in patients with interstitial lung disease (ILD). Growing evidence highlights the significance of sleep disturbance on health outcomes in this population. The relationships between ILD and OSA are complex and possibly bidirectional, with multiple mechanisms postulated for the pathogenic and physiologic links. This review synthesizes current evidence and hypotheses regarding different aspects of the relationships between ILD and OSA, emphasizing the interactions between epidemiology, pathogenesis, and pathophysiology.

The prevalence of obstructive sleep apnea in interstitial lung disease: a systematic review and meta-analysis

PURPOSE

To evaluate the overall prevalence of obstructive sleep apnea (OSA) in interstitial lung disease (ILD).

METHODS

We performed a systematic search of the academic literature while adhering to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines on four scientific databases including EMBASE, CENTRAL, Scopus, and MEDLINE. We performed a meta-analysis to evaluate the prevalence and severity of OSA. Severity was defined by apnea-hypopnea index (AHI) as mild (AHI ≥ 5 to < 15/h), moderate (AHI ≥ 15 to < 30/h), and severe (AHI ≥ 30/h).

RESULTS

From 1397 studies, we found 10 eligible studies with 569 patients with ILD (mean age: 65.3 ± 6.0 years). Among these patients, 332 (61%) suffered from OSA with 32% categorized as mild, 17% moderate, and 9% severe.  CONCLUSION: This systematic review and meta-analysis provides preliminary evidence regarding the high prevalence of OSA in ILD.

An Integrated Approach Toward the Clinical and Polysomnographic Characteristics of OSA Accompanying IPF

OBJECTIVES

Coincidance of idiopathic pulmonary fibrosis (IPF) and the obstructive sleep apnea syndrome (OSA) may have important effects on the pathogenesis of each other. Our aim is to define clinical characteristics of patients with IPF and OSA and to identify a combined index to determine the severity of both diseases together.

MATERIALS AND METHODS

The clinical and polysomnographic characteristics of 22 patients with OSA and IPF who underwent nocturnal polysomnography (NPSG) were retrospectively evaluated and compared with 23 OSA patients without any other pulmonary comorbidities.

RESULTS

We demonstrated high frequency of OSA within our study group (94,7%) all of whom had at least one of the majör symptoms of OSA. Lower AHI, lower neck circumference, higher percentage of deep sleep (nREM3) and less comorbidities were observed in the study group when compared to OSA with no other pulmonary comorbidities (p<0,05). When restaged into a compound index according to the gender, age and physiology (GAP) index, the patients with mild IPF and OSA showed the same life and sleep quality with the patients who have higher GAP index.

CONCLUSION

All patients with IPF must be questioned for the major symptoms of sleep related breathing disorders (SRBD). Clinical suspicion for OSA must prompt NPSG. With the presence of moderate-severe OSA, the life and sleep quality of patients with mild IPF can be at the same level of patients with severe IPF.

Obstructive sleep apnea in patients with interstitial lung disease: Prevalence and predictive factors

Interstitial lung diseases (ILDs) are chronic, progressive, parenchymal lung diseases with high morbidity and mortality. In recent studies, the prevalence of obstructive sleep apnea (OSA) in patients with ILD has been reported to be high. However, the prevalence and predictive factors of OSA in Korean ILD patients are not well defined. Therefore, the aim of this study was to evaluate the prevalence and predictive factors of OSA in Korean patients with ILD. Clinical data from 86 patients with ILD enrolled from December 2017 to April 2019 at Haeundae-Paik Hospital, Busan, South Korea, were retrospectively analyzed. OSA was monitored with a level 4 portable device and defined as an apnea-hypopnea index of more than 5 per hour of sleep. The median follow-up period was 7 months. The mean age was 69.8 years, and 64% of participants were men. Among the ILDs, idiopathic pulmonary fibrosis (IPF) was the most common (66.3%), followed by connective tissue disease-associated ILD (16.3%) and cryptogenic organizing pneumonia (5.8%). Forty-six ILD patients (53.5%) were diagnosed with OSA, and IPF patients had OSA more frequently (64.9% vs. 31.0%, p = 0.003) than those with other ILDs. Older age (odds ratio [OR], 1.11, 95% CI 1.04-1.19, p = 0.002), higher body weight (OR 1.05, 95% CI 1.01-1.10, p = 0.012), and diabetes mellitus (OR 4.03, 95% CI 1.26-12.91, p = 0.019) were independent risk factors for OSA in the multivariable logistic regression analysis. In the multivariable Cox analysis, an IPF diagnosis was a significant risk factor for one-year mortality (hazard ratio [HR] 7.92, 95% CI: 1.01-61.83, p = 0.048) in ILD patients; however, OSA was not. In conclusion, half of Korean patients with ILD had OSA. Older age, higher body weight, and diabetes mellitus were risk factors for OSA in patients with ILD.

Frequency of Obstructive Sleep Apnea in Stage I and II Sarcoidosis Subjects Who Had No Corticosteroid Therapy

OBJECTIVES

The number of studies on the frequency of obstructive sleep apnea (OSA) in subjects with sarcoidosis is low. Therefore, we aimed to investigate the frequency and predictors of OSA in subjects with clinically stable stage I and II sarcoidosis who were not taking corticosteroid and/or immunosuppressive drugs. We also evaluated restless legs syndrome (RLS) and periodic leg movements in sleep (PLMS).

MATERIALS AND METHODS

Subjects with clinically stable stage I and II sarcoidosis and not receiving corticosteroid and/or immunosuppressive therapy were included in the study. Upper airway examination, lung function tests (forced vital capacity [FVC], forced expiratory volume in 1 second [FEV1], diffusing capacity of the lungs for carbon monoxide [DLCO]), and polysomnography were performed on all subjects. In addition, subjects' Epworth Sleepiness Scale (ESS) scores and the Pittsburgh Sleep Quality Index (PSQI) were recorded.

RESULTS

Of the total number of 46 sarcoidosis subjects (35 women, 11 men; age: 44.4±10.7 years; body mass index (BMI): 29.3±5 kg/m2), 28 (60.9%) were detected with OSA (67.8% mild OSA). The recorded ESS score of the subjects was low (2.6±3.2), whereas the sleep quality was poor in 36.9% of these subjects. Rapid eye movements (REM) related OSA was diagnosed in 14.2% of the OSA subjects. Age was the only factor related to OSA diagnosis in a logistic regression analysis (p=0.048). None of the subjects were diagnosed with RLS and PLMS.

CONCLUSION

OSA is common in stage I and II sarcoidosis subjects who did not receive corticosteroid therapy. The frequency of OSA diagnosis increases as the age of the subjects increases. Therefore, sarcoidosis subjects should be evaluated for OSA throughout the follow-up.

Sleep-related breathing disorders and pulmonary hypertension

Sleep-related breathing disorders (SBDs) include obstructive apnoea, central apnoea and sleep-related hypoventilation. These nocturnal events have the potential to increase pulmonary arterial pressure (PAP) during sleep but also in the waking state. "Pure" obstructive sleep apnoea syndrome (OSAS) is responsible for a small increase in PAP whose clinical impact has not been demonstrated. By contrast, in obesity hypoventilation syndrome (OHS) or overlap syndrome (the association of chronic obstructive pulmonary disease (COPD) with obstructive sleep apnoea (OSA)), nocturnal respiratory events contribute to the development of pulmonary hypertension (PH), which is often severe. In the latter circumstances, treatment of SBDs is essential in order to improve pulmonary haemodynamics.Patients with pulmonary arterial hypertension (PAH) or chronic thromboembolic pulmonary hypertension (CTEPH) are at risk of developing SBDs. Obstructive and central apnoea, as well as a worsening of ventilation-perfusion mismatch, can be observed during sleep. There should be a strong suspicion of SBDs in such a patient population; however, the precise indications for sleep studies and the type of recording remain to be specified. The diagnosis of OSAS in patients with PAH or CTEPH should encourage treatment with continuous positive airway pressure (CPAP). The presence of isolated nocturnal hypoxaemia should also prompt the initiation of long-term oxygen therapy. These treatments are likely to avoid worsening of PH; however, it is prudent not to treat central apnoea and Cheyne-Stokes respiration (CSR) with adaptive servo-ventilation in patients with chronic right-heart failure because of a potential risk of serious adverse effects from such treatment.In this review we will consider the current knowledge of the consequences of SBDs on pulmonary haemodynamics in patients with and without chronic respiratory disease (group 3 of the clinical classification of PH) and the effect of treatments of respiratory events during sleep on PH. The prevalence and consequences of SBDs in PAH and CTEPH (groups 1 and 4 of the clinical classification of PH, respectively), as well as therapeutic options, will also be discussed.

Managing Fatigue in Patients With Interstitial Lung Disease

Fatigue is one of the most burdensome symptoms in interstitial lung disease (ILD) and can have a major impact on quality of life, social interactions, and work capacity. The cause of fatigue is complex; it is caused or aggravated by a combination of different predisposing, precipitating, and perpetuating factors. There is no uniform definition of fatigue, but it is often divided in physical and mental components. Several validated questionnaires can be used for structural assessment of fatigue in daily care. Although the high burden of fatigue in ILD is recognized increasingly, studies that have investigated pharmacologic and nonpharmacologic treatment options are scarce. Because fatigue in ILD is often a multifactorial problem, therapeutic interventions ideally should be aimed at different domains. One of the first steps is to optimize treatment of the underlying disease. Subsequently, treatable causes of fatigue should be identified and treated. Recently, an increasing number of studies showed that supportive measures have the potential to improve fatigue. However, evidence-based treatment guidelines are lacking, and more research is highly needed in this field. In clinical practice, a comprehensive, multidisciplinary, and individually tailored approach seems best fit to optimize treatment of fatigue in patients with ILD.

Impact of concomitant obstructive sleep apnea on pulmonary involvement and main pulmonary artery diameter in adults with scleroderma

Purpose

Pulmonary involvement is common in adults with scleroderma. The effect of concomitant obstructive sleep apnea (OSA) on risk for pulmonary hypertension in scleroderma is unknown. An enlarged main pulmonary artery diameter (mPAD) derived from chest computer tomography (CT) is a useful predictor of pulmonary hypertension. We addressed the effect of OSA on pulmonary involvement and enlarged mPAD in adults with scleroderma.

Methods

All participants underwent pulmonary function testing, carbon monoxide diffusion capacity, chest CT, and overnight sleep recording with home sleep apnea testing. OSA diagnosis was based on an apnea-hypopnea index (AHI) ≥ 15/h. Oxygen desaturation index (ODI) was also recorded. Scleroderma involvement of the lungs was defined as the Warrick score ≥ 7 based on the CT findings. Enlarged mPAD was defined as an mPAD ≥ 29 mm in men and ≥ 27 mm in women.

Results

After exclusions, 62 patients (58 women) were included. OSA was found among 20 (32%), 17/42 (38%) in the limited cutaneous type, and 3/20 (15%) in the diffuse cutaneous type (p = 0.08). Scleroderma involvement of the lungs was observed in 40 participants (65% in OSA vs 64% in no-OSA; n.s.). Enlarged mPAD was measured in 16 participants, 10 of 20 (50%) in the OSA group and 6 of 17 (14%) in the no-OSA group (p = 0.003). OSA was associated with enlarged mPAD (odds ratio 4.7, 95% confidence interval 1.1–20.9; p = 0.042) independent of age, body mass index, and pulmonary involvement. There was a linear relationship between mPAD and AHI (r = 0.37; p = 0.003) as well as ODI (r = 0.41; p < 0.001).

Conclusions

In this cohort, OSA was associated with risk for pulmonary hypertension independent of pulmonary involvement. These findings suggest that assessing the effect of therapy for concomitant OSA in patients with scleroderma is warranted.

Trial registration

NCT 02740569

Obstructive sleep apnea in patients with interstitial lung disease: Prevalence and predictive factors

Interstitial lung diseases (ILDs) are chronic, progressive, parenchymal lung diseases with high morbidity and mortality. In recent studies, the prevalence of obstructive sleep apnea (OSA) in patients with ILD has been reported to be high. However, the prevalence and predictive factors of OSA in Korean ILD patients are not well defined. Therefore, the aim of this study was to evaluate the prevalence and predictive factors of OSA in Korean patients with ILD. Clinical data from 86 patients with ILD enrolled from December 2017 to April 2019 at Haeundae-Paik Hospital, Busan, South Korea, were retrospectively analyzed. OSA was monitored with a level 4 portable device and defined as an apnea-hypopnea index of more than 5 per hour of sleep. The median follow-up period was 7 months. The mean age was 69.8 years, and 64% of participants were men. Among the ILDs, idiopathic pulmonary fibrosis (IPF) was the most common (66.3%), followed by connective tissue disease-associated ILD (16.3%) and cryptogenic organizing pneumonia (5.8%). Forty-six ILD patients (53.5%) were diagnosed with OSA, and IPF patients had OSA more frequently (64.9% vs. 31.0%, p = 0.003) than those with other ILDs. Older age (odds ratio [OR], 1.11, 95% CI 1.04-1.19, p = 0.002), higher body weight (OR 1.05, 95% CI 1.01-1.10, p = 0.012), and diabetes mellitus (OR 4.03, 95% CI 1.26-12.91, p = 0.019) were independent risk factors for OSA in the multivariable logistic regression analysis. In the multivariable Cox analysis, an IPF diagnosis was a significant risk factor for one-year mortality (hazard ratio [HR] 7.92, 95% CI: 1.01-61.83, p = 0.048) in ILD patients; however, OSA was not. In conclusion, half of Korean patients with ILD had OSA. Older age, higher body weight, and diabetes mellitus were risk factors for OSA in patients with ILD.

Prevalence and profile of sleep-disordered breathing and obstructive sleep apnea in patients with interstitial lung disease at the pulmonary medicine department of a tertiary care hospital in Mumbai

Background:

Sleep-disordered breathing (SDB), predominantly obstructive sleep apnea (OSA), is a frequent phenomenon in interstitial lung disease (ILD) and may be associated with significant morbidity and mortality.

Methodology:

A prospective, observational, hospital-based study was conducted in a tertiary care hospital after ethics committee permission. The study group consisted of 100 consecutive ILD patients diagnosed by a multidisciplinary diagnosis. They were evaluated for the prevalence of SDB with a polysomnography after a comprehensive history, detailed clinical examination, calculation of various pretest probability scores, and relevant prerequisite workup.

Results:

Out of the total 100 ILD patients, 44 were male (44%) and 56 were female (56%). SDB was present in 57 (57%) patients. Of these, 29 (29%) were found to have only nocturnal oxygen desaturation (NOD), while 28 (28%) had OSA. The 28 cases of OSA were distributed as 15 mild OSA (53.57%), 10 moderate OSA (35.71%), and 3 severe OSA (10.71%). The patients were divided into the following four groups: total study Group (A), patients with OSA (Group B), patients with NOD without OSA (Group C), and no SDB (Group D). The mean forced vital capacity values predicted in the four groups were 53.67%, 50%, 45.56%, and 57.87%, respectively. The mean body mass index in the four groups was 24.56, 27, 26.98, and 24.89 kg/m², respectively. The mean 6-min walk distance in the four groups was 280.7, 250, 256.65, and 311.4 m, respectively. The mean partial pressure of oxygen in the four groups was 65.65, 60, 62.10, and 75.66 mmHg, respectively. The mean apnea–hypopnea index in the study group was 2.98/h, 8.6/h with mild OSA, 21.69/h with moderate OSA, 48.78/h with severe OSA, 3.89/h in patients having NOD without OSA, and 2.54/h in patients with no SDB.

Conclusion:

SDB in ILD is associated with a significant impact on the cardinal determinants of functional capacity, lung function, and quality of life.

The uses of overnight pulse oximetry

Overnight pulse oximetry (OPO) has proven to be an effective and beneficial technique to determine the cardiorespiratory status of patients in both the inpatient and outpatient settings. It is a cheap, safe, reliable, simple, and accurate method of patient monitoring as compared to the expensive and labor-intensive method of multichannel polysomnography for detecting sleep-disordered breathing. It provides accurate information about patient's oxygenation status and also helps in monitoring the response to continuous positive airway pressure and in the surgical treatment of obstructive sleep apnea (OSA). Nocturnal hypoxemia portends a poor prognosis in patients of chronic obstructive pulmonary disease (COPD), interstitial lung disease (ILD), and neuromuscular diseases. OPO can help its early detection and management.

Obstructive Sleep Apnea in Patients With Fibrotic Interstitial Lung Disease and COPD

STUDY OBJECTIVES

Despite the clinical and prognostic significance of obstructive sleep apnea (OSA) in chronic respiratory diseases (CRDs), there have been few studies about the possible predictors of OSA and the effect of OSA on quality of life in patients with CRDs. The objectives were to identify physiological and clinical parameters that predict the occurrence and severity of OSA and to investigate the effect of OSA on quality of life in patients with CRDs.

METHODS

Seventy-three patients with chronic obstructive pulmonary disease (COPD) and 77 patients with fibrotic interstitial lung disease (ILD) underwent overnight polysomnography (PSG) and pulmonary function testing and completed clinical questionnaires. The oximetry tracing was interpreted blindly with respect to the PSG results.

RESULTS

The prevalence of OSA was 44% and 62% in COPD and ILD, respectively. The COPD assessment test item scores related to sleep quality and daily vitality were worse among patients with OSA than among patients without OSA. The STOP-BANG questionnaire (cutoff point ≥ 3) and oxygen desaturation index from the oximetry recording (oxygen desaturation index (ODI) were associated with OSA in CRDs. The STOP-BANG questionnaire with a cutoff point ≥ 3 or 6 had the highest sensitivity and specificity, respectively, in detecting OSA in CRDs. ODI had the best accuracy in identifying OSA and was independently associated with the apnea-hypopnea index in CRDs.

CONCLUSIONS

We found OSA to be common and associated with worse sleep quality and less daily vitality in patients with advanced CRDs. The STOP-BANG questionnaire with different cutoff points may help rule in or rule out OSA. Overnight oximetry can be used as a screening tool for OSA and can assist the clinical evaluation of OSA in patients with CRDs.

First Description of the Hyperpnea-Hypopnea Periodic Breathing in Patients with Interstitial Lung Disease-Obstructive Sleep Apnea: Treatment Implications in a Real-Life Setting

There is evidence that hypopneas are more common than apneas in obstructive sleep apnea (OSA) related to idiopathic pulmonary fibrosis (IPF). We investigated the frequency distribution of hypopneas in 100 patients with interstitial lung diseases (ILDs) (mean age 69 yrs ± 7.8; 70% males), including 54 IPF cases, screened for OSA by home sleep testing. Fifty age- and sex-matched pure OSA patients were included as controls. In ILD-OSA patients the sleep breathing pattern was characterized by a high prevalence of hypopneas that were preceded by hyperpnea events configuring a sort of periodic pattern. This finding, we arbitrarily defined hyperpnea–hypopnea periodic breathing (HHPB), was likely reflecting a central event and was completely absent in control OSA. Also, the HHPB was highly responsive to oxygen but not to the continuous positive pressure support. Thirty-three ILD-OSA patients (42%) with a HHPB associated with a hypopnea/apnea ratio ≥3 had the best response to oxygen with a median residual AHI of 2.6 (1.8–5.6) vs. 28.3 (20.7–37.8) at baseline (p < 0.0001). ILD-OSA patients with these characteristics were similarly distributed in IPF (54.5%) and no-IPF cases (45.5%), the most of them being affected by moderate–severe OSA (p = 0.027). Future studies addressing the pathogenesis and therapy management of the HHPB should be encouraged in ILD-OSA patients.

Pulmonary hypertension due to interstitial lung disease

PURPOSE OF REVIEW

Pulmonary hypertension has been reported to complicate the course of a number of fibrotic lung diseases, including idiopathic pulmonary fibrosis, chronic hypersensitivity pneumonitis and nonspecific interstitial pneumonitis. Most commonly, mild elevations in the mean pulmonary artery pressure are seen in patients with advanced pulmonary fibrosis. However, some patients may develop severe pulmonary hypertension, which appears out of proportion to the degree of their restrictive lung disease.

RECENT FINDINGS

The benefits of pulmonary vasodilator therapy have yet to be established in pulmonary hypertension complicating fibrotic lung disease. In fact, one recent clinical trial examining riociguat in patients with pulmonary hypertension complicating idiopathic interstitial pneumonias was terminated early for an increased risk of death or hospitalization. Multiple clinical trials on this topic are currently ongoing, including studies examining inhaled pulmonary vasodilator therapies.

SUMMARY

The development of pulmonary hypertension is associated with increased exertional oxygen requirements, worsened functional capacity and attenuated life expectancy. It is hoped that continued research will find an effective therapy for this condition, which will improve quality of life and extend life expectancy in patients with this condition.

The prevalence of poor sleep quality and its associated factors in patients with interstitial lung disease: a cross-sectional analysis

Background

Many patients with interstitial lung disease (ILD) experience poor sleep quality, which may contribute to decreased quality of life. Sleep disordered breathing is commonly associated with ILD but there is less information on other factors that may contribute to poor sleep quality.

Methods

We conducted a cross-sectional analysis of 101 patients with a diagnosis of ILD at a pulmonary rehabilitation assessment clinic. We assessed the prevalence of poor sleep quality using the Pittsburgh Sleep Quality Index (PSQI) and performed multivariable logistic regression analysis to determine factors independently associated with poor sleep quality.

Results

Median forced expiratory volume in 1 s was 64% predicted (interquartile range (IQR) 50–77%) and vital capacity was 62% predicted (IQR 48–78%). 67 (66%) out of 101 patients reported poor sleep quality. The median PSQI was 8 units (IQR 4–11 units). There were no significant differences in physical or physiological parameters including age, sex distribution, body mass index or spirometry values between subjects with good sleep quality and those with poor sleep quality (all p>0.1). Multivariable logistic regression showed that depression (p=0.003) and Epworth Sleepiness Scale (p=0.03) were independently associated with poor sleep quality.

Conclusion

Poor sleep quality is common in patients with ILD and is independently associated with increasing symptoms of depression and sleepiness. Routine assessment of sleep quality should be undertaken and interventions targeting depression and coexisting sleep disorders may be required in symptomatic patients to determine if sleep quality and ultimately, health-related quality of life improves as a result.

Poor sleep quality is common in patients with interstitial lung disease and is independently associated with increasing symptoms of depression and sleepinesshttp://bit.ly/2WeQbzw

Pulmonary Manifestations of Systemic Sclerosis and Mixed Connective Tissue Disease

Systemic sclerosis (SSc) is a rare disease characterized by widespread collagen deposition resulting in fibrosis. Although skin involvement is the most common manifestation and also the one that determines the classification of disease, mortality in SSc is usually a result of respiratory compromise in the form of interstitial lung disease (ILD) or pulmonary hypertension (PH). Clinically significant ILD is seen in up to 40% of patients and PH in up to 20%. Treatment with either cyclophosphamide or mycophenolate has been shown to delay disease progression, whereas rituximab and lung transplantation are reserved for refractory cases.

Diagnosing complications and co-morbidities of fibrotic interstitial lung disease

Introduction: Interstitial lung diseases (ILDs) represent a heterogeneous group of rare disorders that include more than 200 entities, mostly associated with high mortality. In recent years, the progress regarding the understanding of the pathogenesis of these diseases led to the approval of specific treatments. In ILDs, the presence of comorbidities has a significant impact on the quality of life and the survival of patients and, therefore, their diagnosis and treatment has a pivotal role in management and could improve overall outcome. Areas covered: We discuss key diagnostic issues with regard to the most frequent comorbidities in ILDs. Treatment options are also discussed as the decision to investigate more definitively in order to identify specific comorbidities (including lung cancer, pulmonary hypertension, GE reflux, and obstructive sleep apnoea) is critically dependent upon whether comorbidity-specific treatments are likely to be helpful in individual patients, judged on a case by case basis. Expert opinion: The extent to which clinicians proactively pursue the identification of comorbidities depends on realistic treatment goals in individual patients.

Obesity and sarcoidosis: consequence or contributor?

PURPOSE OF REVIEW

Sarcoidosis is a multisystem disease of unknown cause. Obesity can affect many physiological factors. The relationship between obesity and sarcoidosis is unclear, and can been described as posing a 'chicken and egg' scenario for the patient as it is not always clear whether it is a consequence of, or a risk factor for any disease. The purpose of this review is to examine the dual roles of obesity on sarcoidosis morbidity and the incidence.

RECENT FINDINGS

Obesity magnifies the symptoms of sarcoidosis and corticosteroid therapy increases BMI. Prospective epidemiologic studies started to explore the role of obesity as a potential risk factor for sarcoidosis. Three studies in the United States, and one study in Denmark, have demonstrated significantly increased risks of sarcoidosis among obese compared with nonobese patients; risk estimates ranged from 1.42 [95% confidence interval (CI), 1.07-1.89] to 3.59 (95% CI, 2.31-5.57).

SUMMARY

Obesity can be both a consequence of sarcoidosis treatment, and a contributor to disease risk likely through the pro-inflammatory environment of obesity. Prospective epidemiologic cohort studies are needed to explore the cause of sarcoidosis and insight into possible avenues of treatment development and prevention.