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pane-page-title" > <div class="pane-content"> <div class="highwire-comments-count-summary" id="comments-summary-wrapper"> <h1 class="highwire-comments-count page-title">341 e-Letters</h1></div> </div> </div> </div> </div> </div> </div>  <div class="panel-row-wrapper clearfix"> <div class="main-content-wrapper grid-17 suffix-1 alpha"> <div class="panel-panel panel-region-content"> <div class="inside"><div class="panel-pane pane-highwire-article-comments-all" > <div class="pane-content"> <div class = "highwire-comments-list-all-wrapper"><div class="hw-comments-filter-wrapper"><form class="hw-comments-filter" action="/eletters" method="post" id="highwire-comments-filters-form" accept-charset="UTF-8"><div><input type="hidden" name="custom_redirect" value="eletters" /> <input type="hidden" name="query_parameters" value="" /> <div class="form-item form-item-label-before form-type-select form-item-pager-limit"> <label for="edit-pager-limit">Results/page </label> <select id="edit-pager-limit" name="pager_limit" class="form-select"><option value="10" selected="selected">10</option><option value="25">25</option><option value="50">50</option><option value="75">75</option><option value="100">100</option></select> </div> <div class="form-item form-item-label-before form-type-select form-item-sort"> <label for="edit-sort">Order by </label> <select id="edit-sort" name="sort" class="form-select"><option value="ASC">Oldest First</option><option value="DESC" selected="selected">Newest First</option></select> </div> <input id="highwire_comments_filter_form_submit" type="submit" name="op" value="Submit" class="form-submit" /><input type="hidden" name="form_build_id" value="form-Rl8D7PFs7PWagaHkOAClmZtpXJb_GxWZIfCo3lLwiuk" /> <input type="hidden" name="form_id" value="highwire_comments_filters_form" /> </div></form></div><div class="highwire-list highwire-article-citation-list"><ul class="highwire-comments"><li class="first odd"><div class="highwire-article-citation highwire-citation-type-highwire-comment" data-node-nid="212519" id="node-2125192095738722"><div class="highwire-cite highwire-cite-highwire-comment highwire-citation-bmjj-comment highwire-comment-view highwire-comment-view-212519 clearfix"> <a href="https://thorax.bmj.com/content/79/12/1145.responses#getting-on-the-front-foot-in-airways-disease-time-to-target-disease-activity" class="highwire-comment-anchor-title-link highwire-cite-linked-title" data-icon-position="" data-hide-link-title="0"><span class="highwire-cite-title highwire-comment-view-title">Getting on the front foot in airways disease: time to target disease activity</span></a> <div class="highwire-cite-metadata"><span class="highwire-cite-metadata-date highwire-cite-metadata">26 November, 2024 </span></div> <div class="highwire-cite-snippet"><div class="highwire-comment-view-body"><div class="highwire-showhide-toggle-short highwire-showhide-toggle"><p>We read with interest very large dataset of Filipow et al1, the conclusions of which were that paediatric asthma should be managed by symptoms not spirometry. The authors interpret the variability in first second forced expired volume (FEV1) between occasions when asthma is well controlled as evidence that a change in spirometry is not useful in the clinical management of asthma. Their data could also be used to show that symptoms are not accurately reported in the clinic (which is well known), and therefore spirometry should be the gold standard! However, in the 21st century, when we treat asthma with anti-inflammatory therapy, should we not be measuring what we are trying to treat, namely inflammation2? Both in adults3 and children4,5, elevated peripheral blood eosinophil count (BEC) and exhaled nitric oxide (FeNO) are established markers of active, high-risk disease, and we need to be exploring strategies to use them effectively in treatment, so that those with active inflammation (raised BEC and FeNO) get more anti-inflammatory therapy to try to prevent attacks, and those with inactive disease (low biomarkers) can wean anti-inflammatory treatment. </p> <p>References<br /> 1. Filipow N, Turner S, Petsky HL, et al. Variability in forced expiratory volume in 1 s in children with symptomatically well-controlled asthma. Thorax 2024; 79(12): 1145-50.</p> <p>2. Pavord ID, Beasley R, Agusti A, et al. After asthma: redefining airways diseases. Lancet (London, England) 2018; 391...</p><a href="#" class="highwire-showhide-toggle-show-more highwire-showhide-toggle-link" data-icon-position="" data-hide-link-title="0">Show More</a></div> <div class="highwire-showhide-toggle-full highwire-showhide-toggle" style="display:none"><p>We read with interest very large dataset of Filipow et al1, the conclusions of which were that paediatric asthma should be managed by symptoms not spirometry. The authors interpret the variability in first second forced expired volume (FEV1) between occasions when asthma is well controlled as evidence that a change in spirometry is not useful in the clinical management of asthma. Their data could also be used to show that symptoms are not accurately reported in the clinic (which is well known), and therefore spirometry should be the gold standard! However, in the 21st century, when we treat asthma with anti-inflammatory therapy, should we not be measuring what we are trying to treat, namely inflammation2? Both in adults3 and children4,5, elevated peripheral blood eosinophil count (BEC) and exhaled nitric oxide (FeNO) are established markers of active, high-risk disease, and we need to be exploring strategies to use them effectively in treatment, so that those with active inflammation (raised BEC and FeNO) get more anti-inflammatory therapy to try to prevent attacks, and those with inactive disease (low biomarkers) can wean anti-inflammatory treatment. </p> <p>References<br /> 1. Filipow N, Turner S, Petsky HL, et al. Variability in forced expiratory volume in 1 s in children with symptomatically well-controlled asthma. Thorax 2024; 79(12): 1145-50.</p> <p>2. Pavord ID, Beasley R, Agusti A, et al. After asthma: redefining airways diseases. Lancet (London, England) 2018; 391(10118): 350-400.</p> <p>3. Couillard S, Laugerud A, Jabeen M, et al. Derivation of a prototype asthma attack risk scale centred on blood eosinophils and exhaled nitric oxide. Thorax 2022; 77(2): 199-202.</p> <p>4. Couillard S, Ducharme FM, Pavord ID. Clinically accessible biomarkers to assess the modifiable risk of asthma/wheezing attacks in toddlers. The Journal of Allergy and Clinical Immunology: In Practice 2023; 11(6): 1984-5.<br /> 5. Bacharier LB, Pavord ID, Maspero JF, Jackson DJ, Fiocchi AG, Mao X, Jacob-Nara JA, Deniz Y, Laws E, Mannent LP, Amin N, Akinlade B, Staudinger HW, Lederer DJ, Hardin M. Blood eosinophils and fractional exhaled nitric oxide are prognostic and predictive biomarkers in childhood asthma. J Allergy Clin Immunol. 2024;154(1):101-110.</p> <a href="#" class="highwire-showhide-toggle-show-less highwire-showhide-toggle-link" data-icon-position="" data-hide-link-title="0">Show Less</a></div> </div> </div> </div> </div></li><li class="even"><div class="highwire-article-citation highwire-citation-type-highwire-comment" data-node-nid="210943" id="node-2109431474701584"><div class="highwire-cite highwire-cite-highwire-comment highwire-citation-bmjj-comment highwire-comment-view highwire-comment-view-210943 clearfix"> <a href="https://thorax.bmj.com/content/79/10/970.responses#how-many-grams-of-alcohol-on-average-were-given-to-the-subjects-of-this-study" class="highwire-comment-anchor-title-link highwire-cite-linked-title" data-icon-position="" data-hide-link-title="0"><span class="highwire-cite-title highwire-comment-view-title">How many grams of alcohol on average were given to the subjects of this study?</span></a> <div class="highwire-cite-metadata"><span class="highwire-cite-metadata-date highwire-cite-metadata">18 September, 2024 </span></div> <div class="highwire-cite-snippet"><div class="highwire-comment-view-body"><p>The article states that on average, 114.5 mL of “pure vodka” was administered to the experimental subjects. Without information on the percentage of alcohol by volume of the vodka, it is not possible to know the average number of grams of alcohol given to the subjects in the study.</p> <p>Would the authors kindly supply the information on the percentage of alcohol by volume of the vodka used in this study?</p> </div> </div> </div> </div></li><li class="odd"><div class="highwire-article-citation highwire-citation-type-highwire-comment" data-node-nid="210531" id="node-2105311835350477"><div class="highwire-cite highwire-cite-highwire-comment highwire-citation-bmjj-comment highwire-comment-view highwire-comment-view-210531 clearfix"> <a href="https://thorax.bmj.com/content/79/8/754.responses#bridging-the-gap-between-lung-function-trajectories-and-the-clinic" class="highwire-comment-anchor-title-link highwire-cite-linked-title" data-icon-position="" data-hide-link-title="0"><span class="highwire-cite-title highwire-comment-view-title">Bridging the gap between lung function trajectories and the clinic</span></a> <div class="highwire-cite-metadata"><span class="highwire-cite-metadata-date highwire-cite-metadata">16 July, 2024 </span></div> <div class="highwire-cite-snippet"><div class="highwire-comment-view-body"><div class="highwire-showhide-toggle-short highwire-showhide-toggle"><p>We read with great interest this latest valuable addition by Zhang et al. to the growing evidence describing lung function trajectories. Although a relatively small cohort, this study has remarkable retention of participants with lung function measurements from the age of 3 to 45 years, bridging the existing gap in the literature between birth cohort and mid-adult life studies. The authors identify ten FEV1 trajectories, notably more than previous studies, by using a best fitting model with an upper limit of twelve trajectories. Trajectories which rise and fall are of interest as potential targets for public health intervention. Whilst the parallel course of most trajectories identified thus far by this and other cohorts do not inspire confidence in modifiability, their 10-class model does reveal additional decline and catch-up groups not identified by a 6-class model in the supplement. This raises the question as to whether there has been an oversimplification in lung function trajectory modelling in previous analyses, which select between just three and six classes[1–4]. </p> <p>Our interest was particularly sparked by data in supplementary figure S8 where individual lung function trajectories are displayed by class, in which FEV1 in the ‘persistently low’ trajectory demonstrated considerable variability. For clinicians, this individual variability is the hallmark of asthma, especially when combined with the strong association of childhood airway hyper-responsiveness. Th...</p><a href="#" class="highwire-showhide-toggle-show-more highwire-showhide-toggle-link" data-icon-position="" data-hide-link-title="0">Show More</a></div> <div class="highwire-showhide-toggle-full highwire-showhide-toggle" style="display:none"><p>We read with great interest this latest valuable addition by Zhang et al. to the growing evidence describing lung function trajectories. Although a relatively small cohort, this study has remarkable retention of participants with lung function measurements from the age of 3 to 45 years, bridging the existing gap in the literature between birth cohort and mid-adult life studies. The authors identify ten FEV1 trajectories, notably more than previous studies, by using a best fitting model with an upper limit of twelve trajectories. Trajectories which rise and fall are of interest as potential targets for public health intervention. Whilst the parallel course of most trajectories identified thus far by this and other cohorts do not inspire confidence in modifiability, their 10-class model does reveal additional decline and catch-up groups not identified by a 6-class model in the supplement. This raises the question as to whether there has been an oversimplification in lung function trajectory modelling in previous analyses, which select between just three and six classes[1–4]. </p> <p>Our interest was particularly sparked by data in supplementary figure S8 where individual lung function trajectories are displayed by class, in which FEV1 in the ‘persistently low’ trajectory demonstrated considerable variability. For clinicians, this individual variability is the hallmark of asthma, especially when combined with the strong association of childhood airway hyper-responsiveness. This suggests a potential target for intensification of asthma management in this group and the possibility of inducing a ‘catch-up’ phase. </p> <p>In summary we commend this paper which we feel highlights the need to clinically phenotype abnormal trajectories more thoroughly. To date lung function trajectory studies have relied on questionnaire-based self-reported diagnoses of asthma and chest infections. We would argue this is insufficient and should be enriched with objectives physiological measures and biomarkers, especially given the clinical difficulty of diagnosing asthma[5]. To introduce meaningful interventions we need the information we would rely on as clinicians: clinical records of respiratory disease and treatment, markers of type 2 inflammation, assessment of small airways involvement, and even thoracic imaging. </p> <p>1 Belgrave DCM, Granell R, Turner SW, et al. Lung function trajectories from pre-school age to adulthood and their associations with early life factors: a retrospective analysis of three population-based birth cohort studies. Lancet Respir Med. 2018;6:526–34.<br /> 2 Berry CE, Billheimer D, Jenkins IC, et al. A Distinct Low Lung Function Trajectory from Childhood to the Fourth Decade of Life. Am J Respir Crit Care Med. 2016;194:607–12.<br /> 3 Bui DS, Lodge CJ, Burgess JA, et al. Childhood predictors of lung function trajectories and future COPD risk: a prospective cohort study from the first to the sixth decade of life. Lancet Respir Med. 2018;6:535–44.<br /> 4 Wang G, Hallberg J, Faner R, et al. Plasticity of Individual Lung Function States from Childhood to Adulthood. Am J Respir Crit Care Med. ;207:406–15.<br /> 5 Kavanagh J, Jackson DJ, Kent BD. Over- and under-diagnosis in asthma. Breathe. 2019;15:e20–7.</p> <a href="#" class="highwire-showhide-toggle-show-less highwire-showhide-toggle-link" data-icon-position="" data-hide-link-title="0">Show Less</a></div> </div> </div> </div> </div></li><li class="even"><div class="highwire-article-citation highwire-citation-type-highwire-comment" data-node-nid="210438" id="node-210438668010578"><div class="highwire-cite highwire-cite-highwire-comment highwire-citation-bmjj-comment highwire-comment-view highwire-comment-view-210438 clearfix"> <a href="https://thorax.bmj.com/content/79/5/422.responses#response-to-letter-to-editors" class="highwire-comment-anchor-title-link highwire-cite-linked-title" data-icon-position="" data-hide-link-title="0"><span class="highwire-cite-title highwire-comment-view-title">Response to Letter to Editors</span></a> <div class="highwire-cite-metadata"><span class="highwire-cite-metadata-date highwire-cite-metadata">17 April, 2024 </span></div> <div class="highwire-cite-snippet"><div class="highwire-comment-view-body"><div class="highwire-showhide-toggle-short highwire-showhide-toggle"><p>We thank Professors Azuma and Raghu for their excellent suggestions and comments on our paper. Our study demonstrates the importance of pulmonary vascular resistance (PVR) as a prognostic factor in the initial evaluation of patients with interstitial lung disease (ILD) and highlights the greater significance of PVR over mPAP in right heart catheterisation (RHC) (1). We acknowledge that there is generally less emphasis on PVR compared to the more commonly discussed mean pulmonary arterial pressure (mPAP), and it was our intention to address this discrepancy with our study.<br /> It is important to clarify that we do not recommend systematic RHC at initial evaluation of ILD. Historically, our approach was to perform RHC more frequently at diagnosis, but in recent years, we have limited this to cases where pulmonary hypertension (PH) is suspected. We recently reported a system for predicting mPAP > 20mmHg using a Pa/Ao ratio ≥ 0.9, PaO2 < 80 Torr, and DLco percent predicted < 50% in patients with idiopathic pulmonary fibrosis (IPF) (2). We propose using this system to screen patients before undergoing RHC, with assessments of both mPAP and PVR.<br /> As Azuma and colleagues pointed out, exercise tolerance tests, including the 6-minute walk test (6MWT), might help in predicting PH. As patients with PH have significantly worse desaturation and walking distance in the 6MWT, those who show significant desaturation and/or reduced walking distance during 6MWT are likely to...</p><a href="#" class="highwire-showhide-toggle-show-more highwire-showhide-toggle-link" data-icon-position="" data-hide-link-title="0">Show More</a></div> <div class="highwire-showhide-toggle-full highwire-showhide-toggle" style="display:none"><p>We thank Professors Azuma and Raghu for their excellent suggestions and comments on our paper. Our study demonstrates the importance of pulmonary vascular resistance (PVR) as a prognostic factor in the initial evaluation of patients with interstitial lung disease (ILD) and highlights the greater significance of PVR over mPAP in right heart catheterisation (RHC) (1). We acknowledge that there is generally less emphasis on PVR compared to the more commonly discussed mean pulmonary arterial pressure (mPAP), and it was our intention to address this discrepancy with our study.<br /> It is important to clarify that we do not recommend systematic RHC at initial evaluation of ILD. Historically, our approach was to perform RHC more frequently at diagnosis, but in recent years, we have limited this to cases where pulmonary hypertension (PH) is suspected. We recently reported a system for predicting mPAP > 20mmHg using a Pa/Ao ratio ≥ 0.9, PaO2 < 80 Torr, and DLco percent predicted < 50% in patients with idiopathic pulmonary fibrosis (IPF) (2). We propose using this system to screen patients before undergoing RHC, with assessments of both mPAP and PVR.<br /> As Azuma and colleagues pointed out, exercise tolerance tests, including the 6-minute walk test (6MWT), might help in predicting PH. As patients with PH have significantly worse desaturation and walking distance in the 6MWT, those who show significant desaturation and/or reduced walking distance during 6MWT are likely to have PH. We agree that there is a need for the development of non-invasive tests that can detect PH and elevated PVR in an earlier stage.</p> <p>1. Thorax. 2024 Apr 15;79(5):422-429.<br /> 2. Furukawa T, et al. Eur Respir J. 2018 Jan 18;51(1):1701311.</p> <a href="#" class="highwire-showhide-toggle-show-less highwire-showhide-toggle-link" data-icon-position="" data-hide-link-title="0">Show Less</a></div> </div> </div> </div> </div></li><li class="odd"><div class="highwire-article-citation highwire-citation-type-highwire-comment" data-node-nid="210354" id="node-2103541004586470"><div class="highwire-cite highwire-cite-highwire-comment highwire-citation-bmjj-comment highwire-comment-view highwire-comment-view-210354 clearfix"> <a href="https://thorax.bmj.com/content/79/5/422.responses#letter-to-editors" class="highwire-comment-anchor-title-link highwire-cite-linked-title" data-icon-position="" data-hide-link-title="0"><span class="highwire-cite-title highwire-comment-view-title">Letter to Editors</span></a> <div class="highwire-cite-metadata"><span class="highwire-cite-metadata-date highwire-cite-metadata">15 April, 2024 </span></div> <div class="highwire-cite-snippet"><div class="highwire-comment-view-body"><div class="highwire-showhide-toggle-short highwire-showhide-toggle"><p>" We congratulate Sato et al to have undertaken the retrospective stud(y that surfaces clinical significance of pulmonary vascular resistance (PVR) as a predictor of mortality in patients with newly diagnosed ILD with normal mean MAP – i.e., < 30mmhg at rest ( 1) . </p> <p>While their obsrervation is interesting , are the authors advocating right heart catheterization(RHC) for patients with new onset ILD upfront at the time of initial evaluation undergoing diagnostic interventions for diagnosis of ILD ?</p> <p> Indeed, RHC is an invasive procedure, and the potential benefits and risks must be weighed in considering RHC for patients with new onset ILD for prognostication and consideration of possible therapeutic interventions. Are the authors recommending RHC for patients with new onset ILD without clues for pulmonary hypertension ?<br /> Do the authors have additional non invasive clinical variables/data that correlate with PVR > 2 wood units with mean PAP < 20 mmHg- such as decreased DLCO corrected for hemoglobin, oxygen desaturation with walking, extent of interstitial lung abnormalities , specific diagnosis in patients with new onset ILD that can be used to screen patients to undergo RHC ?<br /> Perhaps, a noninvasive method using an exercise test as was used in assessing patient's endurance of exercise in patients with IPF treated with pirfenidone for IPF(2) might be a screening test prior to considering RHC as a routine for patients with new ons...</p><a href="#" class="highwire-showhide-toggle-show-more highwire-showhide-toggle-link" data-icon-position="" data-hide-link-title="0">Show More</a></div> <div class="highwire-showhide-toggle-full highwire-showhide-toggle" style="display:none"><p>" We congratulate Sato et al to have undertaken the retrospective stud(y that surfaces clinical significance of pulmonary vascular resistance (PVR) as a predictor of mortality in patients with newly diagnosed ILD with normal mean MAP – i.e., < 30mmhg at rest ( 1) . </p> <p>While their obsrervation is interesting , are the authors advocating right heart catheterization(RHC) for patients with new onset ILD upfront at the time of initial evaluation undergoing diagnostic interventions for diagnosis of ILD ?</p> <p> Indeed, RHC is an invasive procedure, and the potential benefits and risks must be weighed in considering RHC for patients with new onset ILD for prognostication and consideration of possible therapeutic interventions. Are the authors recommending RHC for patients with new onset ILD without clues for pulmonary hypertension ?<br /> Do the authors have additional non invasive clinical variables/data that correlate with PVR > 2 wood units with mean PAP < 20 mmHg- such as decreased DLCO corrected for hemoglobin, oxygen desaturation with walking, extent of interstitial lung abnormalities , specific diagnosis in patients with new onset ILD that can be used to screen patients to undergo RHC ?<br /> Perhaps, a noninvasive method using an exercise test as was used in assessing patient's endurance of exercise in patients with IPF treated with pirfenidone for IPF(2) might be a screening test prior to considering RHC as a routine for patients with new onset ILD " .</p> <p>1. Sato T, et al Thorax 2024<br /> 2. Azuma A, et al AJRCCM 2005</p> <a href="#" class="highwire-showhide-toggle-show-less highwire-showhide-toggle-link" data-icon-position="" data-hide-link-title="0">Show Less</a></div> </div> </div> </div> </div></li><li class="even"><div class="highwire-article-citation highwire-citation-type-highwire-comment" data-node-nid="209298" id="node-2092981350690178"><div class="highwire-cite highwire-cite-highwire-comment highwire-citation-bmjj-comment highwire-comment-view highwire-comment-view-209298 clearfix"> <a href="https://thorax.bmj.com/content/79/3/281.responses#continuous-positive-airway-pressure-in-chronic-hypercapnic-respiratory-failure" class="highwire-comment-anchor-title-link highwire-cite-linked-title" data-icon-position="" data-hide-link-title="0"><span class="highwire-cite-title highwire-comment-view-title">Continuous positive airway pressure in chronic hypercapnic respiratory failure</span></a> <div class="highwire-cite-metadata"><span class="highwire-cite-metadata-date highwire-cite-metadata">15 February, 2024 </span></div> <div class="highwire-cite-snippet"><div class="highwire-comment-view-body"><div class="highwire-showhide-toggle-short highwire-showhide-toggle"><p>Dear editor,<br /> I read with interest the state-of-the-art review article by Shah et al1. on the effects of non-invasive ventilation (NIV) on sleep in chronic hypercapnic respiratory failure. However, I wish to delve deeper into the topic of Continuous Positive Airway Pressure (CPAP) especially in patients with Chronic Obstructive Pulmonary Disease-Obstructive Sleep Apnea (COPD-OSA) overlap syndrome and obesity hypoventilation syndrome (OHS).<br /> COPD-OSA overlap syndrome was first described by Professor Flenley2, which is associated with an increased frequency and severity of COPD exacerbations3, hospitalizations3, and mortality4. Current data indicates that CPAP improves these outcomes5.<br /> Similarly, in OHS, OSA is highly prevalent, affecting an estimated 90% of patients with OHS6. CPAP has been demonstrated to offer similar benefits to NIV6 7 and is recommended as the initial treatment for stable OHS patients8. CPAP therapy enhances outcomes by improving ventilation, reducing air-trapping, enhancing diaphragmatic function, improving hypercapnic response, and decreasing CO2 production resulting from excessive respiratory muscle work9. Given its advantages and cost-effectiveness compared to NIV, CPAP devices should be considered the initial treatment option7 for both disease before NIV. </p> <p>Reference<br /> 1. Shah NM, Steier J, Hart N, Kaltsakas G. Effects of non-invasive ventilation on sleep in chronic hypercapnic respiratory failure. Thorax 2023 doi: 10.1136...</p><a href="#" class="highwire-showhide-toggle-show-more highwire-showhide-toggle-link" data-icon-position="" data-hide-link-title="0">Show More</a></div> <div class="highwire-showhide-toggle-full highwire-showhide-toggle" style="display:none"><p>Dear editor,<br /> I read with interest the state-of-the-art review article by Shah et al1. on the effects of non-invasive ventilation (NIV) on sleep in chronic hypercapnic respiratory failure. However, I wish to delve deeper into the topic of Continuous Positive Airway Pressure (CPAP) especially in patients with Chronic Obstructive Pulmonary Disease-Obstructive Sleep Apnea (COPD-OSA) overlap syndrome and obesity hypoventilation syndrome (OHS).<br /> COPD-OSA overlap syndrome was first described by Professor Flenley2, which is associated with an increased frequency and severity of COPD exacerbations3, hospitalizations3, and mortality4. Current data indicates that CPAP improves these outcomes5.<br /> Similarly, in OHS, OSA is highly prevalent, affecting an estimated 90% of patients with OHS6. CPAP has been demonstrated to offer similar benefits to NIV6 7 and is recommended as the initial treatment for stable OHS patients8. CPAP therapy enhances outcomes by improving ventilation, reducing air-trapping, enhancing diaphragmatic function, improving hypercapnic response, and decreasing CO2 production resulting from excessive respiratory muscle work9. Given its advantages and cost-effectiveness compared to NIV, CPAP devices should be considered the initial treatment option7 for both disease before NIV. </p> <p>Reference<br /> 1. Shah NM, Steier J, Hart N, Kaltsakas G. Effects of non-invasive ventilation on sleep in chronic hypercapnic respiratory failure. Thorax 2023 doi: 10.1136/thorax-2023-220035 [published Online First: 20231118]<br /> 2. Flenley DC. Sleep in chronic obstructive lung disease. Clin Chest Med 1985;6(4):651-61.<br /> 3. Brennan M, McDonnell MJ, Walsh SM, et al. Review of the prevalence, pathogenesis and management of OSA-COPD overlap. Sleep Breath 2022;26(4):1551-60. doi: 10.1007/s11325-021-02540-8 [published Online First: 20220116]<br /> 4. Marin JM, Soriano JB, Carrizo SJ, et al. Outcomes in patients with chronic obstructive pulmonary disease and obstructive sleep apnea: the overlap syndrome. Am J Respir Crit Care Med 2010;182(3):325-31. doi: 10.1164/rccm.200912-1869OC [published Online First: 20100408]<br /> 5. Srivali N, Thongprayoon C, Tangpanithandee S, et al. The use of continuous positive airway pressure in COPD-OSA overlap syndrome: A systematic review. Sleep Med 2023;108:55-60. doi: 10.1016/j.sleep.2023.05.025 [published Online First: 20230608]<br /> 6. Masa JF, Corral J, Alonso ML, et al. Efficacy of Different Treatment Alternatives for Obesity Hypoventilation Syndrome. Pickwick Study. Am J Respir Crit Care Med 2015;192(1):86-95. doi: 10.1164/rccm.201410-1900OC<br /> 7. Masa JF, Mokhlesi B, Benitez I, et al. Cost-effectiveness of positive airway pressure modalities in obesity hypoventilation syndrome with severe obstructive sleep apnoea. Thorax 2020;75(6):459-67. doi: 10.1136/thoraxjnl-2019-213622 [published Online First: 20200326]<br /> 8. Mokhlesi B, Masa JF, Brozek JL, et al. Evaluation and Management of Obesity Hypoventilation Syndrome. An Official American Thoracic Society Clinical Practice Guideline. Am J Respir Crit Care Med 2019;200(3):e6-e24. doi: 10.1164/rccm.201905-1071ST<br /> 9. McNicholas WT. COPD-OSA Overlap Syndrome: Evolving Evidence Regarding Epidemiology, Clinical Consequences, and Management. Chest 2017;152(6):1318-26. doi: 10.1016/j.chest.2017.04.160 [published Online First: 20170423]</p> <a href="#" class="highwire-showhide-toggle-show-less highwire-showhide-toggle-link" data-icon-position="" data-hide-link-title="0">Show Less</a></div> </div> </div> </div> </div></li><li class="odd"><div class="highwire-article-citation highwire-citation-type-highwire-comment" data-node-nid="209734" id="node-2097341167226139"><div class="highwire-cite highwire-cite-highwire-comment highwire-citation-bmjj-comment highwire-comment-view highwire-comment-view-209734 clearfix"> <a href="https://thorax.bmj.com/content/79/2/144.responses#baseline-post-pe-assessment" class="highwire-comment-anchor-title-link highwire-cite-linked-title" data-icon-position="" data-hide-link-title="0"><span class="highwire-cite-title highwire-comment-view-title">Baseline post-PE assessment</span></a> <div class="highwire-cite-metadata"><span class="highwire-cite-metadata-date highwire-cite-metadata">07 February, 2024 </span></div> <div class="highwire-cite-snippet"><div class="highwire-comment-view-body"><p>Thank you to the authors for the excellent and very interesting work published. </p> <p>I would like to ask about the protocol routine follow-up of patients following an acute pulmonary embolus mentioned in the paper: what did this entail, and how did it differ from the protocol implemented as part of the trial? </p> <p>Secondly, how did the authors select a follow-up telephone at 2 years post acute pulmonary embolus? As is pointed out in the limitations of section of the paper, this could have missed patients with clinically significant CTEPH who did not survive those 2 years. Would an earlier symptom assessment have led to a greater incidence of false positive echocardiograms showing pulmonary hypertension, or would it lead to patients being missed as not enough time would have passed to allow CTEPH to establish?</p> <p>Thank you in advance for your clarifications</p> </div> </div> </div> </div></li><li class="even"><div class="highwire-article-citation highwire-citation-type-highwire-comment" data-node-nid="208222" id="node-208222696572429"><div class="highwire-cite highwire-cite-highwire-comment highwire-citation-bmjj-comment highwire-comment-view highwire-comment-view-208222 clearfix"> <a href="https://thorax.bmj.com/content/78/12/1240.responses#underrepresentation-of-low--and-middle-income-countries-in-core-outcome-set-for-pulmonary-rehabilitation-of-patients-with-copd-results-of-a-modified-delphi-survey" class="highwire-comment-anchor-title-link highwire-cite-linked-title" data-icon-position="" data-hide-link-title="0"><span class="highwire-cite-title highwire-comment-view-title">Underrepresentation of low- and middle-income countries in "Core outcome set for pulmonary rehabilitation of patients with COPD: results of a modified Delphi survey"</span></a> <div class="highwire-cite-metadata"><span class="highwire-cite-metadata-date highwire-cite-metadata">20 November, 2023 </span></div> <div class="highwire-cite-snippet"><div class="highwire-comment-view-body"><div class="highwire-showhide-toggle-short highwire-showhide-toggle"><p>If a core outcome set (COS) to a global burden of disease is to be globally relevant and applicable, methodological efforts to ensure equal representation of low- and middle-income countries (LMICs) and high-income countries (HICs) at all stages of its development are needed (1, 2). This is due to the differences in disease patterns, healthcare resources, culture, and biomedical beliefs, which may influence outcome priorities (3, 4). A case in point is a study by Van Rijssen et al (5), where participants from Europe, the USA, and Asia did not reach the same consensus on the final patient-reported COS for pancreatic cancer, and Asian participants did not reach a consensus on any outcomes included in the final set.</p> <p>We read with interest your COS for pulmonary rehabilitation (PR) of patients with COPD in the 2023 September issue of Thorax "(6). We noticed the under-representation of LMICs, especially in Asia and Africa, in your development of the COS. Of the 29 and 27 countries where you recruited participants in the first and second rounds of your Delphi survey, respectively, Asia was represented by only one participant from India, whilst no participant was recruited from Africa. Most participants were from HICs in Europe including the Netherlands, Portugal, United Kingdom, Australia, and Spain.</p> <p>This underrepresentation of LMICs is noteworthy given that, firstly, the burden of chronic respiratory diseases (including COPD) is greater in LMICs, both in terms...</p><a href="#" class="highwire-showhide-toggle-show-more highwire-showhide-toggle-link" data-icon-position="" data-hide-link-title="0">Show More</a></div> <div class="highwire-showhide-toggle-full highwire-showhide-toggle" style="display:none"><p>If a core outcome set (COS) to a global burden of disease is to be globally relevant and applicable, methodological efforts to ensure equal representation of low- and middle-income countries (LMICs) and high-income countries (HICs) at all stages of its development are needed (1, 2). This is due to the differences in disease patterns, healthcare resources, culture, and biomedical beliefs, which may influence outcome priorities (3, 4). A case in point is a study by Van Rijssen et al (5), where participants from Europe, the USA, and Asia did not reach the same consensus on the final patient-reported COS for pancreatic cancer, and Asian participants did not reach a consensus on any outcomes included in the final set.</p> <p>We read with interest your COS for pulmonary rehabilitation (PR) of patients with COPD in the 2023 September issue of Thorax "(6). We noticed the under-representation of LMICs, especially in Asia and Africa, in your development of the COS. Of the 29 and 27 countries where you recruited participants in the first and second rounds of your Delphi survey, respectively, Asia was represented by only one participant from India, whilst no participant was recruited from Africa. Most participants were from HICs in Europe including the Netherlands, Portugal, United Kingdom, Australia, and Spain.</p> <p>This underrepresentation of LMICs is noteworthy given that, firstly, the burden of chronic respiratory diseases (including COPD) is greater in LMICs, both in terms of mortality (90%) and disability-adjusted life years (7). Secondly, the unmet needs for PR (such as unavailability of expertise, equipment, access, awareness, low uptake, and lack of training) are more profound in LMICs (8-11). Thirdly, the lack of participation from Africa does not reflect the growing body of PR literature on the continent (12, 13). Fourthly, choosing appropriate outcomes to measure is a topic most important to researchers in LMICs (14). Given these facts, there is a need for greater involvement of LMICS in the development of COS.</p> <p>You acknowledged the underrepresentation of LMICs in your paper but did not acknowledge limitations in your participant recruitment methods that might have resulted in such underrepresentation. The lack of representation from Africa is of concern to us as Africa-based PR researchers/practitioners. The use of a more rigorous and appropriate methodology in qualitative research has the potential to increase the community’s confidence in COS (15). Your COS was partly informed by two qualitative studies (16, 17) but most of their participants (people with COPD and healthcare professionals) were from HICs in Europe, Pacific/Oceania, and North America. Again, no participant was recruited from Africa despite the existence of PR evidence in the continent as shown in your own systematic review (18) and ours (12, 13).</p> <p>To explore barriers and enablers to PR in LMICs, Bickton et al interviewed PR professionals from these countries (10). To identify potential participants from these countries, they reviewed papers included in two systematic reviews on PR in LMICs and sent invitation/recruitment emails to their corresponding authors. You should have used a similar purposive sampling approach to ensure participation from Africa. You would then use the PR professionals from Africa identified this way to locally interview (19) patients with spirometry-confirmed COPD and/or their caregivers in their native languages where necessary, for English translation later. Another example is the RECHARGE project, which used consensus meetings between PR researchers from the UK and four LMICs to establish a COS for PR in LMICs (20). Their limitation was not following rigorous methods (21), but they demonstrated the feasibility of HIC–LMIC research partnerships in developing a COS for PR. Finally, on respiratory health matters, Africa is continentally represented by the Pan-African Thoracic Society (PATS; <a href="https://panafricanthoracic.org/">https://panafricanthoracic.org/</a>). Recently, PATS inaugurated its PR Working Group to further give a voice and platform for African PR professionals to promote PR in Africa. Of the 21 societies/associations that you contacted to recruit participants; PATS was not one of them. </p> <p>Underrepresentation of LMICs in COS development studies has been previously acknowledged (2, 4, 22-24). If we are to attain good health and wellbeing for all (SDG 3) and move towards global health, it is time that COS development researchers start addressing the underrepresentation of LMICs. This is in line with a Core Outcome Measures in Effectiveness Trials (COMET) recommendation (25).</p> <p>References </p> <p>1. Davies PA, Davies AK, Kirkham JJ, Young AE. Secondary analysis of data from a core outcome set for burns demonstrated the need for involvement of lower income countries. J Clin Epidemiol. 2022;144:56-71.</p> <p>2. Davis K, Gorst SL, Harman N, Smith V, Gargon E, Altman DG, et al. Choosing important health outcomes for comparative effectiveness research: An updated systematic review and involvement of low and middle income countries. PLoS One. 2018;13(2):e0190695.</p> <p>3. Jan RB, Rusham Zahra R, Jamie JK, Louise R, Gina A, Corrado B, et al. Development of a core outcome set for multimorbidity trials in low/middle-income countries (COSMOS): study protocol. BMJ Open. 2022;12(2):e051810.</p> <p>4. Lee A, Davies A, Young AE. Systematic review of international Delphi surveys for core outcome set development: representation of international patients. BMJ Open. 2020;10(11):e040223.</p> <p>5. van Rijssen LB, Gerritsen A, Henselmans I, Sprangers MA, Jacobs M, Bassi C, et al. Core Set of Patient-reported Outcomes in Pancreatic Cancer (COPRAC): An International Delphi Study Among Patients and Health Care Providers. Annals of Surgery. 2019;270(1).</p> <p>6. Souto-Miranda S, Saraiva I, Spruit MA, Marques A. Core outcome set for pulmonary rehabilitation of patients with COPD: results of a modified Delphi survey. Thorax. 2023.</p> <p>7. Global burden of chronic respiratory diseases and risk factors, 1990-2019: an update from the Global Burden of Disease Study 2019. EClinicalMedicine. 2023;59:101936.</p> <p>8. Gimigliano F, Negrini S. The World Health Organization "Rehabilitation 2030: a call for action". Eur J Phys Rehabil Med. 2017;53(2):155-68.</p> <p>9. Singh SJ, Halpin DMG, Salvi S, Kirenga BJ, Mortimer K. Exercise and pulmonary rehabilitation for people with chronic lung disease in LMICs: challenges and opportunities. Lancet Respir Med. 2019;7(12):1002-4.</p> <p>10. Bickton FM, Shannon H. Barriers and Enablers to Pulmonary Rehabilitation in Low- and Middle-Income Countries: A Qualitative Study of Healthcare Professionals. Int J Chron Obstruct Pulmon Dis. 2022;17:141-53.</p> <p>11. Bilungula A-MM, Orme MW, Bickton FM, Kirenga B, Rylance J, Pina I, et al. Distinguishing pulmonary rehabilitation from chest physiotherapy in the African context. Journal of the Pan African Thoracic Society.4.</p> <p>12. Bickton FM, Fombe C, Chisati E, Rylance J. Evidence for pulmonary rehabilitation in chronic respiratory diseases in sub-Saharan Africa: a systematic review. The International Journal of Tuberculosis and Lung Disease. 2020;24(10):991-9.</p> <p>13. Bilungula AM, Katoto P, Gosselink R, Kayembe JN, Langer D. Pulmonary rehabilitation in Africa: where are we? a multimethod study. Pan Afr Med J. 2022;42:78.</p> <p>14. Rosala-Hallas A, Bhangu A, Blazeby J, Bowman L, Clarke M, Lang T, et al. Global health trials methodological research agenda: results from a priority setting exercise. Trials. 2018;19(1):48.</p> <p>15. Keeley T, Williamson P, Callery P, Jones LL, Mathers J, Jones J, et al. The use of qualitative methods to inform Delphi surveys in core outcome set development. Trials. 2016;17(1):230.</p> <p>16. Souto-Miranda S, Marques A. Triangulated perspectives on outcomes of pulmonary rehabilitation in patients with COPD: a qualitative study to inform a core outcome set. Clin Rehabil. 2019;33(4):805-14.</p> <p>17. Souto-Miranda S, Vaes AW, Gloeckl R, Grongstad A, Spruit MA, Marques A. International perspectives on outcome measurement in pulmonary rehabilitation of people with COPD: A qualitative study. Respir Med. 2022;201:106936.</p> <p>18. Souto-Miranda S, Rodrigues G, Spruit MA, Marques A. Pulmonary rehabilitation outcomes in individuals with chronic obstructive pulmonary disease: A systematic review. Ann Phys Rehabil Med. 2022;65(3):101564.</p> <p>19. Babaji HU, Sulaiman SK, Shittu A, Abubakar Y, Mohammed J. Pulmonary rehabilitation implementation in Northwest Nigeria: A qualitative study of the views of respiratory health-care professionals. Journal of the Pan African Thoracic Society.3.</p> <p>20. Orme MW, Free RC, Manise A, Jones AV, Akylbekov A, Barton A, et al. Global RECHARGE: Establishing a standard international data set for pulmonary rehabilitation in low- and middle-income countries. J Glob Health. 2020;10(2):020316.</p> <p>21. Kirkham JJ, Davis K, Altman DG, Blazeby JM, Clarke M, Tunis S, et al. Core Outcome Set-STAndards for Development: The COS-STAD recommendations. PLOS Medicine. 2017;14(11):e1002447.</p> <p>22. Jamlick K, Sarah LG, David G, Elizabeth G, Bridget Y, Paula RW. Inclusion of participants from low-income and middle-income countries in core outcome sets development: a systematic review. BMJ Open. 2021;11(10):e049981.</p> <p>23. Susan MS, Emma W, Chris S, Maxime S, Elizabeth B, Martin F. A Core Outcome Set for Multimorbidity Research (COSmm). The Annals of Family Medicine. 2018;16(2):132.</p> <p>24. Deshmukh SR, Kirkham JJ, Karantana A. Developing a core outcome set for hand fractures and joint injuries in adults. Bone Jt Open. 2023;4(2):87-95.</p> <p>25. Williamson PR, Altman DG, Bagley H, Barnes KL, Blazeby JM, Brookes ST, et al. The COMET Handbook: version 1.0. Trials. 2017;18(3):280.</p> <a href="#" class="highwire-showhide-toggle-show-less highwire-showhide-toggle-link" data-icon-position="" data-hide-link-title="0">Show Less</a></div> </div> </div> </div> </div></li><li class="odd"><div class="highwire-article-citation highwire-citation-type-highwire-comment" data-node-nid="208233" id="node-208233571728312"><div class="highwire-cite highwire-cite-highwire-comment highwire-citation-bmjj-comment highwire-comment-view highwire-comment-view-208233 clearfix"> <a href="https://thorax.bmj.com/content/78/12/1240.responses#response-to-underrepresentation-of-low--and-middle-income-countries" class="highwire-comment-anchor-title-link highwire-cite-linked-title" data-icon-position="" data-hide-link-title="0"><span class="highwire-cite-title highwire-comment-view-title">Response to "Underrepresentation of low- and middle-income countries"</span></a> <div class="highwire-cite-metadata"><span class="highwire-cite-metadata-date highwire-cite-metadata">20 November, 2023 </span></div> <div class="highwire-cite-snippet"><div class="highwire-comment-view-body"><div class="highwire-showhide-toggle-short highwire-showhide-toggle"><p>We thank Bickton and colleagues for their interest in reading our article and their commentary.<br /> We recognize the need to have a balanced representation of low- and middle-income countries (LMICs) in core outcome sets (COS), specifically in pulmonary rehabilitation (PR) as resources for measurement instruments may vary globally and the burden of COPD and need for pulmonary rehabilitation in these regions are undeniable.<br /> According to the World Bank categories (1), we have included some middle-income countries in our study, from south America (Argentina, Brazil, Colombia, Cuba) and from Asia (not only India, but also the Philippines). Nonetheless, as acknowledged in our COS paper (2), the African and Asian continents were underrepresented.<br /> Although not stated throughout our paper, with the a priori knowledge of the need to include these continents and LMICs, we took some methodological steps to try to ensure their representation. Indeed, we have contacted several professional and patient associations from these regions to help us recruit participants. The Pan African Thoracic Society was contacted directly. Nonetheless, the procedure to contact is a form on a website (<a href="https://panafricanthoracic.org/about-us/contact-us">https://panafricanthoracic.org/about-us/contact-us</a>), with no other form of contact provided. No response was ever obtained. We congratulate the newly formed PR Working Group, and we look forward to enhancing our communication chan...</p><a href="#" class="highwire-showhide-toggle-show-more highwire-showhide-toggle-link" data-icon-position="" data-hide-link-title="0">Show More</a></div> <div class="highwire-showhide-toggle-full highwire-showhide-toggle" style="display:none"><p>We thank Bickton and colleagues for their interest in reading our article and their commentary.<br /> We recognize the need to have a balanced representation of low- and middle-income countries (LMICs) in core outcome sets (COS), specifically in pulmonary rehabilitation (PR) as resources for measurement instruments may vary globally and the burden of COPD and need for pulmonary rehabilitation in these regions are undeniable.<br /> According to the World Bank categories (1), we have included some middle-income countries in our study, from south America (Argentina, Brazil, Colombia, Cuba) and from Asia (not only India, but also the Philippines). Nonetheless, as acknowledged in our COS paper (2), the African and Asian continents were underrepresented.<br /> Although not stated throughout our paper, with the a priori knowledge of the need to include these continents and LMICs, we took some methodological steps to try to ensure their representation. Indeed, we have contacted several professional and patient associations from these regions to help us recruit participants. The Pan African Thoracic Society was contacted directly. Nonetheless, the procedure to contact is a form on a website (<a href="https://panafricanthoracic.org/about-us/contact-us">https://panafricanthoracic.org/about-us/contact-us</a>), with no other form of contact provided. No response was ever obtained. We congratulate the newly formed PR Working Group, and we look forward to enhancing our communication channels to work more closely with them.<br /> We also contacted the Asian Pacific Society of Respirology (APSR), the Philippine College of Chest Physicians, Alpha-1 Israel, Alpha-1 South Africa, and the Global Allergy and Airways Patient Platform. However, to our knowledge, the only institutions disseminating our project were the Philippine College of Chest Physicians, Alpha-1 South Africa and the Global Allergy and Airways Patient Platform.<br /> Furthermore, we had the two main societies of the field disseminating our study within their working groups, the European Respiratory Society and the American Thoracic Society, which are not exclusive to members of Europe or North America. It would also be beneficial for researchers from LMICs to engage, if not already, with these two societies to increase their representativeness in PR assemblies and studies.<br /> Lastly, to increase the outreach, our study was disseminated on social media, specifically Twitter, which was a great resource for recruitment of participants, especially from North and South America. Hence, we encourage African and Asian researchers, healthcare professionals and PR working groups to connect with internationally known societies and researchers on this platform, as they commonly disseminate studies.<br /> We appreciate the suggestion of including in our recruitment strategy the identification of participants from LMICs in PR papers, which we will follow in the future.<br /> We were not aware of other initiatives aiming to develop a COS for PR such as the RECHARGE project, as this project has not been registered in the COMET initiative database (<a href="https://www.comet-initiative.org/Studies">https://www.comet-initiative.org/Studies</a>), which informs researchers of planned, ongoing, or finished COS. Ours was registered in 2017 and since then only another initiative for post-tuberculosis lung disease has been registered (3). Indeed, if we had previous knowledge, it would have been of great interest for us to collaborate with you. Having different COS, and therefore possible divergent recommendations on outcome measurement within the same intervention and disease, will only perpetuate the heterogeneity in outcome measurement in PR (4).<br /> A stronger engagement of LMICs is imperative in international studies, and communication from both ends (LMICs – HICs) needs to improve. A global PR network is much needed where researchers worldwide can connect and unite efforts into more representative PR studies.</p> <p>References<br /> 1. Bank W. World Bank Country and Lending Groups 2023 [Available from: <a href="https://datahelpdesk.worldbank.org/knowledgebase/articles/906519-world-bank-country-and-lending-groups">https://datahelpdesk.worldbank.org/knowledgebase/articles/906519-world-b...</a>.<br /> 2. Sara S-M, Isabel S, Martijn AS, et al. Core outcome set for pulmonary rehabilitation of patients with COPD: results of a modified Delphi survey. Thorax 2023:thorax-2023-220522. doi: 10.1136/thorax-2023-220522<br /> 3. Migliori GB, Marx FM, Ambrosino N, et al. Clinical standards for the assessment, management and rehabilitation of post-TB lung disease. The International Journal of Tuberculosis and Lung Disease 2021;25(10):797-813. doi: 10.5588/ijtld.21.0425<br /> 4. Souto-Miranda S, Rodrigues G, Spruit MA, et al. Pulmonary rehabilitation outcomes in individuals with chronic obstructive pulmonary disease: A systematic review. Ann Phys Rehabil Med 2022;65(3):101564. doi: 10.1016/j.rehab.2021.101564 [published Online First: 20211115]</p> <a href="#" class="highwire-showhide-toggle-show-less highwire-showhide-toggle-link" data-icon-position="" data-hide-link-title="0">Show Less</a></div> </div> </div> </div> </div></li><li class="last even"><div class="highwire-article-citation highwire-citation-type-highwire-comment" data-node-nid="207515" id="node-2075152121301961"><div class="highwire-cite highwire-cite-highwire-comment highwire-citation-bmjj-comment highwire-comment-view highwire-comment-view-207515 clearfix"> <a href="https://thorax.bmj.com/content/78/11/1126.responses#letter-to-the-editors-the-effect-of-vibrotactile-pt-on-patient-with-positional-obstructive-sleep-apnoea-posa" class="highwire-comment-anchor-title-link highwire-cite-linked-title" data-icon-position="" data-hide-link-title="0"><span class="highwire-cite-title highwire-comment-view-title">Letter to the editors. The effect of vibrotactile PT on patient with positional obstructive sleep apnoea (POSA).</span></a> <div class="highwire-cite-metadata"><span class="highwire-cite-metadata-date highwire-cite-metadata">17 October, 2023 </span></div> <div class="highwire-cite-snippet"><div class="highwire-comment-view-body"><div class="highwire-showhide-toggle-short highwire-showhide-toggle"><p>The systematic review and meta-analysis by Abdullah ALQarni et al. on the effect of positional vibrotactile therapy for positional obstructive sleep apnoea shows that this treatment modality is effective, reducing time in the supine position, severity of obstructive sleep apnoea and daytime sleepiness. (1) It also highlights the lack of patient-centered outcomes beyond daytime sleepiness, which is very important to achieve good adherence to treatment, one of the main limitations of obstructive sleep apnoea treatment to achieve greater health benefits for patients as shown by different clinical trials that have failed to show significant results of continuous airway pressure (CPAP) in the prevention of cardiovascular events in intention-to-treat analyses but did show significant results in patients with good adherence to treatment (2).<br /> Based on this statement, we would like to refer you to our last publication (3), a RCT, which shows high good compliance rates for the active device (mean value of 85% ± 36.6%, defined as device use for more than 4 hours per night and more than 70% of nights per week), values above the usual ones for CPAP treatment, (generally 40%–50% in the long term)(4,5), from the first day and sustained form over time. Patient ́s satisfaction was high and minor side effects were reported.<br /> Our previous research showed their efficacy in terms of reduction of Apnoea-Hypopnoea Index, total sleep time in the supine position; improve oxygen saturati...</p><a href="#" class="highwire-showhide-toggle-show-more highwire-showhide-toggle-link" data-icon-position="" data-hide-link-title="0">Show More</a></div> <div class="highwire-showhide-toggle-full highwire-showhide-toggle" style="display:none"><p>The systematic review and meta-analysis by Abdullah ALQarni et al. on the effect of positional vibrotactile therapy for positional obstructive sleep apnoea shows that this treatment modality is effective, reducing time in the supine position, severity of obstructive sleep apnoea and daytime sleepiness. (1) It also highlights the lack of patient-centered outcomes beyond daytime sleepiness, which is very important to achieve good adherence to treatment, one of the main limitations of obstructive sleep apnoea treatment to achieve greater health benefits for patients as shown by different clinical trials that have failed to show significant results of continuous airway pressure (CPAP) in the prevention of cardiovascular events in intention-to-treat analyses but did show significant results in patients with good adherence to treatment (2).<br /> Based on this statement, we would like to refer you to our last publication (3), a RCT, which shows high good compliance rates for the active device (mean value of 85% ± 36.6%, defined as device use for more than 4 hours per night and more than 70% of nights per week), values above the usual ones for CPAP treatment, (generally 40%–50% in the long term)(4,5), from the first day and sustained form over time. Patient ́s satisfaction was high and minor side effects were reported.<br /> Our previous research showed their efficacy in terms of reduction of Apnoea-Hypopnoea Index, total sleep time in the supine position; improve oxygen saturation without deteriorating sleep quality. (6,7). This treatment modality could be used as a primary therapy in Positional Obstructive Sleep Apnoea patients (POSA) or as an alternative in patients who cannot tolerate or are not compliant with the standard CPAP treatment. (3)<br /> Thus, we agree with Abdullah ALQarni et al. (1) that it is important to evaluate patient-centered results that favor treatment compliance, in addition to assessing its effectiveness, that help overcome the current limitations of CPAP and thus contribute to improving the health of patients with POSA.<br /> REFERENCES<br /> 1. ALQarni AS, Turnbull CD, Morrell MJ, Kelly JL. Efficacy of vibrotactile positional therapy devices on patients with positional obstructive sleep apnoea: a systematic review and meta-analysis. Thorax. 21 de junio de 2023;thoraxjnl-2021-218402.<br /> 2. Javaheri S, Martinez-Garcia MA, Campos-Rodriguez F, Muriel A, Peker Y. Continuous Positive Airway Pressure Adherence for Prevention of Major Adverse Cerebrovascular and Cardiovascular Events in Obstructive Sleep Apnea. Am J Respir Crit Care Med. 2020 Mar 1;201(5):607-610. doi: 10.1164/rccm.201908-1593LE. PMID: 31644880.<br /> 3. Hidalgo-Armas L, Inglés S, Vaca R, Cordero-Guevara J, Durán-Carro J, Ullate J, et al. Patient compliance and satisfaction with a new forehead device for positional obstructive sleep apnoea treatment: a post hoc analysis of a randomised controlled trial. BMJ Open Respir Res. junio de 2023;10(1):e001503.<br /> 4. Rotenberg BW, Murariu D, Pang KP. Trends in CPAP adherence over twenty years of data collection: a flattened curve. J Otolaryngol Head Neck Surg 2016;45:43.<br /> 5. Barnes H, Edwards BA, Joosten SA, et al. Positional modification techniques for supine obstructive sleep apnea: A systematic review and meta-analysis. Sleep Med Rev 2017;36:107–15.<br /> 6. Hidalgo Armas L, Turino C, Cordero-Guevara J, Manjón JL, Durán-Carro J, Barbé F, et al. A new postural device for the treatment of positional obstructive sleep apnea. A pilot study. Respir Med. May 2019;151:111-7.<br /> 7. Hidalgo Armas L, Ingles S, Vaca R, Cordero-Guevara J, Duran Carro J, Ullate J, et al. New forehead device in positional obstructive sleep apnoea: a randomised clinical trial. Thorax. 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