Pre-asthma: a useful concept? A EUFOREA paper. Part 2-late onset eosinophilic asthma.

The concept of pre-diabetes has led to provision of measures to reduce disease progression through identification of subjects at risk of diabetes. We previously considered the idea of pre-asthma in relation to allergic asthma and considered that, in addition to the need to improve population health via multiple measures, including reduction of exposure to allergens and pollutants and avoidance of obesity, there are several possible specific means to reduce asthma development in those most at risk (pre- asthma). The most obvious is allergen immunotherapy (AIT), which when given for allergic rhinitis (AR) has reasonable evidence to support asthma prevention in children (2) but also needs further study as primary prevention. In this second paper we explore the possibilities for similar actions in late onset eosinophilic asthma.

Nasal polyp syndrome: a patient-centred term for CRSwNP by EUFOREA.

Chronic Rhinosinusitis with Nasal Polyps (CRSwNP) is a chronic inflammatory disease of the nose and paranasal sinus cavities that significantly affects well-being and social function, particularly in young adults and middle-aged populations. CRSwNP is a common health condition in the Western world, with an estimated prevalence of 3%. Despite worldwide evidence-based treatment guidelines such as the European Position Paper on Rhinosinusitis and Nasal Polyps (EPOS) 2020 and the European Forum for Research and Education in Allergy and Airway Diseases (EUFOREA) chronic rhinosinusitis (CRS) pocket guide, a significant number of patients remain undiagnosed and/or uncontrolled with repeated oral corticosteroids (OCS) treatments and/or (multiple) endoscopic sinus surgeries (ESS).

Nasal hyperreactivity in allergic rhinitis and chronic rhinosinusitis with polyps: a role for neuronal pathways.

BACKGROUND: Nasal hyperreactivity (NHR) is prevalent in all chronic upper airway inflammatory phenotypes, including allergic rhinitis (AR) and chronic rhinosinusitis with nasal polyps (CRSwNP). Although NHR in patients with non-allergic rhinitis is mediated by neuronal pathways, AR and CRSwNP are mainly characterized by type 2 inflammation. METHODS: Eighteen healthy controls and 45 patients with symptomatic AR/CRSwNP underwent a cold, dry air (CDA) provocation test for objective diagnosis of NHR. Before and after, questionnaires were filled out and nasal secretions and biopsies were collected. Markers for neurogenic inflammation (substance P, calcitonin gene-related peptide, neurokinin A), epithelial activation (IL-33), and histamine were measured in secretions by ELISA; and expression of neuronal markers PGP9.5, TRPV1, and TRPM8 was studied in biopsies by RT-q-PCR. Effects of histamine on TRPV1/A1 were studied with Ca2+-imaging using murine trigeminal neurons. RESULTS: CDA-provocation reduced peak nasal inspiratory flow (PNIF) of patients with subjective NHR but not of non-NHR controls/patients CDA-provocation reduced peak nasal inspiratory flow (PNIF) of patients with subjective NHR but not of non-NHR controls/patients. Subjective (subjectively reported effect of CDA) and objective (decrease in PNIF) effects of CDA were significantly correlated. Levels of neuropeptides and histamine in nasal secretions and mRNA expression of PGP9.5, TRPV1, and TRPM8 correlated with CDA-induced PNIF-reduction. CDA-provocation induced an increase in IL-33-levels. Both TRPV1 and TRPA1 expressed on afferent neurons were sensitized by exposure to histamine. CONCLUSION: NHR is not an on/off phenomenon but spans a continuous spectrum of reactivity. A neurogenic inflammatory background and increased histamine-levels are risk factors for NHR in AR/CRSwNP.

EPOS2020/EUFOREA expert opinion on defining disease states and therapeutic goals in CRSwNP.

Severe chronic rhinosinusitis with nasal polyps (CRSwNP), a form of diffuse bilateral (usually type 2) CRS, is a debilitating disease with a significant impact on quality of life (QoL). With novel knowledge and treatment options becoming available, there is a growing need to update or revise key definitions to enable communication across different specialties dealing with CRS, and to agree on novel goals of care in CRSwNP. The European Forum for Research and Education in Allergy and Airway diseases (EUFOREA) and EPOS expert members discussed how to measure treatment responses and set new treatment goals for CRSwNP. In this paper a consensus on a list of definitions related to CRSwNP is provided: control, remission, cure, recurrence/exacerbation, treatable traits, remodeling, progression, and disease modification. By providing these definitions, the involved experts hope to improve communication between all stakeholders involved in CRSwNP treatment for use in routine care, basic and clinical research and international guidelines aimed to harmonize and optimize standard of care of patients with CRSwNP in the future.

Reasons for rejection of rhinoplasty seeking patients: a multicentre observational study.

BACKGROUND: To date, research on preoperative patient selection has mainly focused on patient personality, with body dysmorphic disorder (BDD) being the most studied. Despite the many reasons for not planning a rhinoplasty, no data are available on the nature of these reasons. Our aim is to conduct a multicentre international observational study on the reasons for rejection of patients seeking rhinoplasty in 5 tertiary rhinoplasty care centres. METHODS: Surgeons documented the reasons for not scheduling a rhinoplasty in consecutive patients who consulted them between January 2021 and March 2022 using a predefined list of reasons for rejection. Surgeons were also asked to report on the patient attitudes after rejection, and about the advice given to patients in the event of refusal. RESULTS: 186 patients seeking rhinoplasty were included. Multiple reasons for rejection were present in 76% of patients, with a mean of 2.9 reasons for rejection per patient. Overall, patient-related factors were most frequently associated with rejection (64.3%), followed by nose-related factors (28.4%), surgeon-related factors (6.0 %) and surgery-related factors (1.3%). The presence of severe BDD symptoms was reported in only 11.3% of the rejected patients. Patients rejected for rhinoplasty were advised to reconsider the surgery (32.8 %) and/or were referred to another surgeon (32.8%). No further action was taken in 39.8% of the patients. Of the patients who were rejected, most had a neutral (39.2 %) or positive (37.1 %) attitude in relation to the lack of rhinoplasty planning. CONCLUSION: This study highlights the variety of reasons for which patients seeking rhinoplasty are not considered good candidates for a rhinoplasty, with patient-related factors being more prevalent than nose-related and other factors. Increasing awareness on the impact of adequate patient selection for rhinoplasty may contribute to better outcomes in rhinoplasty.

Consensus criteria for chronic rhinosinusitis disease control: an international Delphi Study.

BACKGROUND: Chronic rhinosinusitis (CRS) disease control is a global metric of disease status for CRS. While there is broad acceptance that it is an important treatment goal, there has been inconsistency in the criteria used to define CRS control. The objective of this study was to identify and develop consensus around essential criteria for assessment of CRS disease control. METHODS: Modified Delphi methodology consisting of three rounds to review a list of 24 possible CRS control criteria developed by a 12-person steering committee. The core authorship of the multidisciplinary EPOS 2020 guidelines was invited to participate. RESULTS: Thirty-two individuals accepted the invitation to participate and there was no dropout of participants throughout the entire study (3 rounds). Consensus essential criteria for assessment of CRS control were: overall symptom severity, need for CRS-related systemic corticosteroids in the prior 6 months, severity of nasal obstruction, and patient-reported CRS control. Near-consensus items were: nasal endoscopy findings, severity of smell loss, overall quality of life, impairment of normal activities and severity of nasal discharge. Participants’ comments provided insights into caveats of, and disagreements related to, near-consensus items. CONCLUSIONS: Overall symptom severity, use of CRS-related systemic corticosteroids, severity of nasal obstruction, and patient-reported CRS control are widely agreed upon essential criteria for assessment of CRS disease control. Consideration of near-consensus items to assess CRS control should be implemented with their intrinsic caveats in mind. These identified consensus CRS control criteria, together with evidence-based support, will provide a foundation upon which CRS control criteria with wide-spread acceptance can be developed.

EUFOREA summit in Brussels 2023: inspiring the future of allergy & respiratory care.

In March 2023, the European Forum for Research and Education in Allergy and Airways diseases (EUFOREA) organized its bi-annual Summit in Brussels with expert panel members of EUFOREA, representatives of the EUFOREA patient advisory board, and the EUFOREA board and management teams. Its aim was to define the research, educational and advocacy initiatives to be developed by EUFOREA over the next 2 years until the 10th anniversary in 2025. EUFOREA is an international non-for-profit organization forming an alliance of all stakeholders dedicated to reducing the prevalence and burden of chronic allergic and respiratory diseases via research, education, and advocacy. Based on its medical scientific core competency, EUFOREA offers an evidence-supported platform to introduce innovation and education in healthcare leading to optimal patient care, bridging the gap between latest scientific evidence and daily practice. Aligned with the mission of improving health care, the expert panels of asthma, allergic rhinitis (AR), chronic rhinosinusitis (CRS) & European Position Paper on Rhinosinusitis and Nasal Polyps (EPOS), allergen immunotherapy (AIT) and paediatrics have proposed and elaborated a variety of activities that correspond to major unmet needs in the allergy and respiratory field. The current report provides a concise overview of the achievements, ambitions, and action plan of EUFOREA for the future, allowing all stakeholders in the allergy and respiratory field to be up-dated and inspired to join forces in Europe and beyond.

EPOS/EUFOREA update on indication and evaluation of Biologics in Chronic Rhinosinusitis with Nasal Polyps 2023.

Severe chronic rhinosinusitis with nasal polyps (CRSwNP) is a debilitating disease with a significant impact on the quality of life (QoL). It is typically characterized by a type 2 inflammatory reaction and by comorbidities such as asthma, allergies and NSAID-Exacerbated Respiratory Disease (N-ERD). Here, the European Forum for Research and Education in Allergy and Airway diseases discusses practical guidelines for patients on biologic treatment. Criteria for the selection of patients who would benefit from biologics were updated. Guidelines are proposed concerning the monitoring of the drug effects that provide recognition of responders to the therapy and, subsequently, the decision about continuation, switching or discontinuation of a biologic. Furthermore, gaps in the current knowledge and unmet needs were discussed.

The EUFOREA pocket guide for chronic rhinosinusitis.

Chronic rhinosinusitis (CRS) is known to affect around 5 % of the total population, with major impact on the quality of life of those severely affected (1). Despite a substantial burden on individuals, society and health economies, CRS often remains underdiagnosed, under-estimated and under-treated (2). International guidelines like the European Position Paper on Rhinosinusitis and Nasal Polyps (EPOS) (3) and the International Consensus statement on Allergy and Rhinology: Rhinosinusitis 2021 (ICAR) (4) offer physicians insight into the recommended treatment options for CRS, with an overview of effective strategies and guidance of diagnosis and care throughout the disease journey of CRS.

Occupational exposure influences control of disease in patients with chronic rhinosinusitis.

BACKGROUND: Chronic rhinosinusitis (CRS) is a frequent condition that is treated by endoscopic sinus surgery (ESS) when medical treatment fails. Irritating or sensitizing airborne agents can contribute to uncontrolled CRS. A prior study showed a linear correlation between occupational exposure and the number of ESS. METHODS: In this cross-sectional study we tested the hypothesis that occupational exposure is a risk for undergoing ESS. We sent questionnaires enquiring occupational exposure in patients with CRS with nasal polyps (CRSwNP) or CRS without nasal polyps (CRSsNP). An expert assessed blindly the reported work exposures to inhaled agents. The relationship between occupational exposure on undergoing ESS was analysed. RESULTS: Among all patients who underwent ESS (n=343), 30% reported a relevant occupational exposure, which is significantly higher than the 4.8% found among CRS patients that underwent no prior sinus surgery (n=21). Besides occupational exposure, self-reported doctor-diagnosed asthma were independent variables contributing to the chance of undergoing ESS. CONCLUSION: In our study we confirm occupational exposure as a risk factor for uncontrolled CRS, if defined by undergoing ESS. In CRS patients with uncontrolled symptoms, despite maximal conservative therapy, the clinician should explore the possible contribution of occupational exposure.

Dupilumab reduces systemic corticosteroid use and sinonasal surgery rate in CRSwNP.

BACKGROUND: Chronic rhinosinusitis with nasal polyps (CRSwNP) is a type 2 inflammatory disease with a high symptom burden and poor quality of life. Treatment options include recurrent surgeries and/or frequent systemic corticosteroids (SCS). Dupilumab, a fully human monoclonal antibody, blocks the shared receptor component for interleukin-4 and interleukin-13, key drivers of type 2-mediated inflammation. We report results of pooled analyses from 2 randomised, double-blind, placebo-controlled phase 3 studies (SINUS 24 [NCT02912468]; SINUS-52 [NCT02898454]) to evaluate dupilumab effect versus placebo in adults with CRSwNP with/without SCS use and sinonasal surgery. METHODOLOGY: SINUS-24 patients were randomised 1:1 to subcutaneous dupilumab 300 mg (n=143) or placebo (n=133) every 2 weeks (q2w) for 24 weeks. SINUS-52 patients were randomised 1:1:1 to 52 weeks of subcutaneous dupilumab 300 mg q2w (n=150), 24 weeks q2w followed by 28 weeks of dupilumab 300 mg every 4 weeks (n=145) or 52 weeks of placebo q2w (n=153). RESULTS: Dupilumab reduced the number of patients undergoing sinonasal surgery (82.6%), the need for in-study SCS use (73.9%), and SCS courses (75.3%). Significant improvements were observed with dupilumab vs placebo regardless of prior sinonasal surgery or SCS use in nasal polyp, nasal congestion, Lund-MacKay, and Sinonasal Outcome Test (22-items) scores, and the University of Pennsylvania Smell Identification Test. CONCLUSIONS: Dupilumab demonstrated significant improvements in disease signs and symptoms and reduced the need for sino-nasal surgery and SCS use versus placebo in patients with severe CRSwNP, regardless of SCS use in the previous 2 years, or prior sinonasal surgery.

State-of-the-art overview on biological treatment for CRSwNP.

BACKGROUND: The majority of patients with uncontrolled severe CRSwNP, asthma and atopic dermatitis share a similar T helper 2 type inflammation linked to their underlying phenotype. This discovery has triggered new research around treatments targeting specific cytokines driving inflammation in CRSwNP like IL-4, IL-13, IL-5 and IgE. Biologicals are increasingly tested as additional tre- atment for patients suffering from severe chronic rhinosinusitis with nasal polyps (CRSwNP). Their efficacy has been demonstrated in multiple studies. All studies differ in terms of baseline characteristics of included patients and outcome parameters analysed. AIMS: A comparative analysis of the efficacy of reported biologicals for CRSwNP based on the published data for phase 2 and 3 studies. The aim was to provide a comprehensive overview across the different biologicals and outcome parameters. METHODS: In a first step we critically selected out of all available phase 2 and 3 clinical trials the ones containing the most rigorous and compatible study designs. Meaning studies that comply with a need for a clear definition of CRSwNP, at least two administra- tion doses, comparable timeframes and the same outcome parameters studied. This assessment was performed using a PRISMA search. We retained 7 studies with significant data for dupilumab, mepolizumab and omalizumab. In a second step the effect-sizes of treatment with those biologicals were compared for the most important outcome parameters both patient relevant (nasal con- gestion, smell loss and SNOT-22 scores) and patient irrelevant (CT scan Lund-Mackay, smell test and nasal polyp scores). Therapy duration of 16 to 25 weeks was chosen for evaluation of efficacy. RESULTS: A direct comparison of efficacy between dupilumab, mepolizumab and omalizumab is challenging given differences in inclusion criteria, outcome parameters and time-points of analyses. We have been able to conclude that effect sizes of dupilumab, mepolizumab and omalizumab seem large enough to reflect a major reduction in symptom burden as experienced by patients suffering from refractory CRSwNP. The effect size of dupilumab on both patient relevant and patient irrelevant parameters of smell loss are clearly significant and reflect the clinical experience of major reduction of smell impairment in treated patients. CONCLUSION: Despite the heterogeneity of protocols, dosages and time-points of analyses of biological trials in CRSwNP, this over- view highlights outcomes of biological treatment in CRSwNP in a comprehensive way. Real-life registries, comparative trials and/ or endotype-driven treatment plans are needed to provide the answers to the multiple questions that are still open today.

Patients Unmet Needs in Chronic Rhinosinusitis With Nasal Polyps Care: A Patient Advisory Board Statement of EUFOREA.

Background: European patients with chronic rhinosinusitis with nasal polyps (CRSwNP) have had only limited occasions to unite to have their voices heard, hence missing the opportunity to contribute to the improvement of CRSwNP care. Aims: To identify unmet needs in CRSwNP from the perspective of CRSwNP patients from the Patient Advisory Board (PAB) of the European Forum for Research and Education in Allergy and Airways diseases (EUFOREA). Methodology: Semi-structured interviews were conducted individually with 15 European patients with CRSwNP and with a disease history of more than 2 years. Patients shared their burden of the disease and frustrations related to CRSwNP care, experiences with key pillars of current treatment options, shortcomings of the current care pathways and recommendations for improvement of care. A panel of 30 members of the Patient Advisory Board reviewed the interview report and provided further input during 2 virtual meetings. Results: CRSwNP patients indicated the need for greater awareness from society and physicians of the disease burden with impact on social function and well-being. Along with a loss of ability to smell and the continuous presence of secretions in the nose, most patients reported poor sleep quality and psychological impact as the most bothersome symptoms. Patients' frustrations relate primarily to the underestimation of the disease burden, the lack of coordination of care and the limited treatment options available to them. Treatment options with oral corticosteroids and/or sinus surgery both have positive and negative aspects, including the lack of long-lasting efficacy. Better coordination of care, more patient-centered care, greater public awareness, increases in research on the disease mechanisms and better therapeutic options would be warmly welcomed by CRSwNP patients. Conclusions: This statement of the EUFOREA Patient Advisory Board on CRSwNP provides novel insights on the underestimation of the burden of CRSwNP and shortcomings of current care. Multiple recommendations made by the patients can underpin action plans for implementation of better care for CRSwNP among all physicians treating patients with this disabling disease.

Corrigendum: Patients Unmet Needs in Chronic Rhinosinusitis With Nasal Polyps Care: A Patient Advisory Board Statement of EUFOREA.

[This corrects the article DOI: 10.3389/falgy.2021.761388.].

Rhinology on the move despite Covid-19!

The October 2020 issue of Rhinology is a very interesting edition as it illustrates how world-wide colleagues pave the way for a better future of patients affected by nose and sinus diseases. After the successful launch of EPOS2020 in Spring 2020, the editorial team of Rhinology is proud to present to you the latest and most exciting data in Rhinology research. Getting insight into the complexity and relevance of proteomics in CRS, epithelial-mesenchymal contribution to CRS, zinc levels in nasal and systemic compartment of CRS, nasal biomarkers of CRSwNP that predict recurrence of disease after sinus surgery, and the odor identification test for children, called "U-Sniff", and FID scores (Frequency, Intensity and Duration) scores for epistaxis are all in the 2020 October issue and highly relevant for Rhinology practice. These studies build further on the solid grounds of previous Rhinology research meeting the unmets needs in the field.

Executive summary of EPOS 2020 including integrated care pathways.

The European Position Paper on Rhinosinusitis and Nasal Polyps 2020 is the update of similar evidence based position papers published in 2005 and 2007 and 2012(1-3). The core objective of the EPOS2020 guideline is to provide revised, up-to-date and clear evidence-based recommendations and integrated care pathways in ARS and CRS. EPOS2020 provides an update on the literature published and studies undertaken in the eight years since the EPOS2012 position paper was published and addresses areas not extensively covered in EPOS2012 such as paediatric CRS and sinus surgery. EPOS2020 also involves new stakeholders, including pharmacists and patients, and addresses new target users who have become more involved in the management and treatment of rhinosinusitis since the publication of the last EPOS document, including pharmacists, nurses, specialised care givers and indeed patients themselves, who employ increasing self-management of their condition using over the counter treatments. The document provides suggestions for future research in this area and offers updated guidance for definitions and outcome measurements in research in different settings.

European Position Paper on Rhinosinusitis and Nasal Polyps 2020.

The European Position Paper on Rhinosinusitis and Nasal Polyps 2020 is the update of similar evidence based position papers published in 2005 and 2007 and 2012. The core objective of the EPOS2020 guideline is to provide revised, up-to-date and clear evidence-based recommendations and integrated care pathways in ARS and CRS. EPOS2020 provides an update on the literature published and studies undertaken in the eight years since the EPOS2012 position paper was published and addresses areas not extensively covered in EPOS2012 such as paediatric CRS and sinus surgery. EPOS2020 also involves new stakeholders, including pharmacists and patients, and addresses new target users who have become more involved in the management and treatment of rhinosinusitis since the publication of the last EPOS document, including pharmacists, nurses, specialised care givers and indeed patients themselves, who employ increasing self-management of their condition using over the counter treatments. The document provides suggestions for future research in this area and offers updated guidance for definitions and outcome measurements in research in different settings. EPOS2020 contains chapters on definitions and classification where we have defined a large number of terms and indicated preferred terms. A new classification of CRS into primary and secondary CRS and further division into localized and diffuse disease, based on anatomic distribution is proposed. There are extensive chapters on epidemiology and predisposing factors, inflammatory mechanisms, (differential) diagnosis of facial pain, allergic rhinitis, genetics, cystic fibrosis, aspirin exacerbated respiratory disease, immunodeficiencies, allergic fungal rhinosinusitis and the relationship between upper and lower airways. The chapters on paediatric acute and chronic rhinosinusitis are totally rewritten. All available evidence for the management of acute rhinosinusitis and chronic rhinosinusitis with or without nasal polyps in adults and children is systematically reviewed and integrated care pathways based on the evidence are proposed. Despite considerable increases in the amount of quality publications in recent years, a large number of practical clinical questions remain. It was agreed that the best way to address these was to conduct a Delphi exercise . The results have been integrated into the respective sections. Last but not least, advice for patients and pharmacists and a new list of research needs are included. The full document can be downloaded for free on the website of this journal: http://www.rhinologyjournal.com.

The GALEN rhinosinusitis cohort: chronic rhinosinusitis with nasal polyps affects health-related quality of life.

BACKGROUND: Chronic rhinosinusitis (CRS) significantly affects health-related quality of life (HRQoL). Few multinational observational studies have evaluated the impact of CRS with nasal polyps (CRSwNP) on patients’ HRQoL. This study aimed to assess HRQoL outcomes (including analyses by disease severity and impact of comorbidities and refractory disease) in CRSwNP patients from a large European database. METHODOLOGY: Data were analysed from the Global Allergy and Asthma European Network (GALEN) Rhinosinusitis Cohort, including sociodemographic data, patient-reported disease severity (visual analogue scale), and scores on the 36-Item ShortForm Health Survey (SF-36) questionnaire. Differences in mean SF-36 scores were evaluated between patients with CRSwNP and population norms and between subgroups of interest (disease severity, comorbidity, and refractory disease, defined by a history of sinonasal surgery). RESULTS: Patients with CRSwNP (N = 445) had significantly lower mean SF-36 Physical Component Summary (PCS) and Mental Component Summary (MCS) scores vs population norms, demonstrating that CRSwNP negatively affects HRQoL. The presence of comorbidities affected HRQoL, as shown by significant differences in PCS scores in patients with asthma or non-steroidal antiinflammatory drug-exacerbated respiratory disease, compared with patients without asthma. Patients with moderate-to-severe disease had significantly lower PCS scores than patients with mild disease. Severe disease had a significant impact on MCS score. History of surgery had a clinically meaningful negative effect on HRQoL compared with no history of surgery. CONCLUSIONS: CRSwNP patients have significantly lower HRQoL compared with population norms. The impact is greater in patients with greater disease severity, comorbidities, or refractory disease.

IL-1ß, IL-23, and TGF-ß drive plasticity of human ILC2s towards IL-17-producing ILCs in nasal inflammation.

Innate lymphoid cells (ILCs) are crucial for the immune surveillance at mucosal sites. ILCs coordinate early eradication of pathogens and contribute to tissue healing and remodeling, features that are dysfunctional in patients with cystic fibrosis (CF). The mechanisms by which ILCs contribute to CF-immunopathology are ill-defined. Here, we show that group 2 ILCs (ILC2s) transdifferentiated into IL-17-secreting cells in the presence of the epithelial-derived cytokines IL-1ß, IL-23 and TGF-ß. This conversion is abrogated by IL-4 or vitamin D3. IL-17 producing ILC2s induce IL-8 secretion by epithelial cells and their presence in nasal polyps of CF patients is associated with neutrophilia. Our data suggest that ILC2s undergo transdifferentiation in CF nasal polyps in response to local cytokines, which are induced by infectious agents.

The Global Allergy and Asthma European Network (GALEN rhinosinusitis cohort: a large European cross-sectional study of chronic rhinosinusitis patients with and without nasal polyps.

BACKGROUND: Chronic rhinosinusitis (CRS) is a common yet under-recognised chronic inflammatory disease of the nose and paranasal sinuses that is classified according to the presence (CRSwNP) or absence (CRSsNP) of nasal polyps. METHODS: This paper reports the methodology and descriptive results of the Global Allergy and Asthma European Network (GALEN) rhinosinusitis cohort. We established a large CRS cohort within the GALEN consortium (European FP6 research initiative) to identify inflammatory endotypes, the natural disease course, and its impact on health-related quality of life (HRQoL). Detailed information on the impact of CRS on HRQoL, comorbidity incidence, objective disease measures, and medical and surgical treatments were collected. RESULTS: This multicentre cross-sectional case-control study recruited 935 adults (869 eligible for analysis: 237 CRSsNP; 445 CRSwNP; 187 controls [reference group]). Comorbidities such as asthma, allergy, eczema, food allergy, urticaria, and chronic obstructive pulmonary disease were significantly more frequent in CRS patients. Nasal corticosteroids, antibiotics, and oral corticosteroids were the most common treatments. Significantly more CRSwNP patients reported previous sinonasal surgery. CONCLUSIONS: This study provides detailed information that facilitates studying CRS and its main phenotypes. However, patient distribution of this study does not necessarily reflect disease distribution in the general population.