The Global Airways Unit: A Multidisciplinary Strategy for Early Diagnosis and Comorbidity Detection

ABSTRACT

Background

Chronic respiratory diseases impose a large global burden of morbidity, mortality, and cost. The concept of a global airway has become increasingly supported by epidemiologic, mechanistic, and clinical evidence. However, clinical care often remains fragmented between ear, nose, and throat (ENT), allergy, and pulmonology.

Methods

A multidisciplinary expert panel composed of allergists, pulmonologists, and otolaryngologists from multiple tertiary care centres was convened. Experts were selected using predefined criteria encompassing clinical experience, academic output, geographic and institutional diversity, and gender balance. The panel performed a structured synthesis of current international guidelines and high‐impact literature, using a modified Delphi consensus process over 3 rounds, with a predefined agreement threshold of ≥ 80% to define the scope of diseases, diagnostic approach, and interdisciplinary care model.

Results

The Global Airways Unit (GAU) framework prioritizes multidisciplinary teamwork, early detection of comorbidities, phenotype‑directed investigations, streamlined imaging, and assignment of a lead specialty with scheduled follow‑up. Expected benefits include earlier diagnosis, improved disease control and quality of life (QoL), reduced duplication of testing, and potential cost‑savings for patients and health systems.

Conclusions

The GAU operationalises the unified airway hypothesis into a reproducible clinical model. We propose the formation of a GAU to coordinate the management of patients with inflammatory airway diseases. Prospective real‑world evaluation of GAU implementation is the next critical step to validate clinical and economic outcomes.

Abbreviations

AERD

aspirin‐exacerbated respiratory disease

AI

artificial intelligence

AR

allergic rhinitis

COPD

chronic obstructive pulmonary disease

CRD

chronic respiratory diseases

CRS

chronic rhinosinusitis

CRSsNP

chronic rhinosinusitis without nasal polyps

CRSwNP

chronic rhinosinusitis with nasal polyps

EMR/EHR

electronic medical record/electronic health record

ENT

ear, nose and throat

FeNO

fractional exhaled nitric oxide

GAU

global airways unit

MDT

multidisciplinary team

OSA

obstructive sleep apnoea

QoL

quality of life

1. Introduction

Chronic Respiratory Diseases (CRDs) are a heterogeneous group of conditions affecting the upper and lower airways, collectively constituting a leading cause of global morbidity. Major CRDs relevant include allergic rhinitis (AR), chronic rhinosinusitis (CRS) with and without nasal polyps (CRSwNP/CRSsNP), asthma (including eosinophilic/type‑2 subtypes), chronic obstructive pulmonary disease (COPD), non‑cystic fibrosis bronchiectasis, and obstructive sleep apnoea (OSA). Each condition individually contributes to symptom burden, impaired function, reduced health‑related QoL, and substantial healthcare utilisation, including OSA, which, although it does not share the same pathophysiological mechanisms, should be considered a factor in the worsening of the overall condition and a factor in the acquisition of new comorbidities [1, 2, 3]. Although patients with this multimorbidity exhibit considerable phenotypic heterogeneity, those with the most severe conditions would benefit most from a synergistic and synchronised multidisciplinary approach [1, 2, 3].

Despite having slightly different and independent immunological functions and specialisations [4, 5], as well as certain nuances in their physiological functions [5, 6], the upper and lower airways are recognized as a functional and immunologic interconnected respiratory tract. Early work in the “one airway, one disease” paradigm emphasised the association between AR and asthma, and the ARIA initiative first codified the importance of assessing upper‐airway disease in patients with asthma [1]. Subsequent mechanistic, epidemiologic, and biomarker studies have supported the concept of “unified airway disease”, in which inflammation in the nasal/sinus mucosa and bronchial tree shares common pathways, especially type 2 eosinophilic inflammation, and co‐occurs more than by chance [7]. Patients with co‐existent upper and lower airway disease frequently experience worse outcomes, higher exacerbation rates, and higher biomarker burdens [8].

Despite growing awareness of airways continuity, care for patients with CRD is often fragmented: allergists manage rhinitis, ENTs manage sinus disease, pulmonologists manage asthma/COPD/bronchiectasis, often without structured coordination. This siloed approach may delay diagnosis of co‐existent pathology, underrecognize comorbid disease, and impair optimal management [7]. While elements of multidisciplinary airway care already exist in clinical practice, for instance joint allergy‐ENT clinics or severe asthma multidisciplinary teams (MDTs), these models typically remain disease‐restricted (e.g., centred on severe asthma or on CRS) and are rarely structured to systematically screen, across specialties, for the full spectrum of inflammatory airway comorbidity. In this context, we propose a dedicated Global Airways Unit (GAU) to deliver integrated diagnostic and management pathways for patients with airway inflammatory disease.

1.1. Rationale and Scope: Why This Matters?

Inflammatory airway diseases represent a major public health challenge. AR, for instance, affects an estimated 10%–30% of the adult global population and up to around 40% in children, with evidence of increasing prevalence [9, 10]. A global review found median prevalences of unspecified rhinitis at 29.4%, allergic rhinitis at 18.1% and non‐allergic rhinitis at 12.0% in adult populations [11]. A Swedish population‐based study of AR estimated annual direct and indirect costs per individual at approximately €961, and a total national annual cost of ~€1.3 billion, with over two‐thirds attributable to productivity loss [12].

CRS has a prevalence of 2%–16% in the general population, and the associated comorbidity with lower airway disease, such as asthma, has been increasingly recognised; the impact on QoL is comparable to that of other chronic respiratory conditions [13, 14]. Lower airway diseases also carry a tremendous burden. Asthma affects approximately 260–300 million individuals worldwide, with recent data indicating regional prevalence ranging from 3.44% in Asia to 8.29% in North America [3]. The economic impact is equally significant: in the United States, asthma's direct plus indirect costs exceeded tens of billions of USD [15]. COPD is one of the most expensive respiratory conditions in Europe, with direct costs alone €38.6 billion annually, representing 6% of total healthcare expenditure in the EU [16, 17]. A systematic review estimated per‐patient direct costs in Europe ranging from €1,963 to over €10,700 annually, and substantial additional losses in productivity [18].

The frequent co‑occurrence of upper and lower airway disease is well documented: around half of people with asthma have comorbid AR, and nasal polyps are enriched in severe and eosinophilic asthma phenotypes [3, 7]. Such comorbidity is associated with worse symptom control, increased risk of exacerbations, and higher biomarker burden [8]. The combined epidemiologic prevalence, the frequent comorbidity between upper and lower airway disease (e.g., AR present in up to 49% of asthma cases globally) [7], and the high socioeconomic cost—both direct (healthcare, medications, hospitalisations) and indirect (productivity loss, absenteeism, presenteeism)—make a compelling case for redesigning care delivery [13, 14, 18]. When patients suffer from multiple airway conditions simultaneously, the adverse impact on disease control, QoL, and healthcare utilisation is magnified.

Given this convergence of prevalence, shared pathophysiology and economic burden, a targeted multidisciplinary management, by means of the GAU, aims to prioritise two tiers of conditions. The first tier comprises core inflammatory unified airway diseases, namely AR, CRSwNP/CRSsNP, asthma (with emphasis on the type 2/eosinophilic phenotype), COPD, and non‐cystic‐fibrosis bronchiectasis, which share overlapping type 2 or mixed inflammatory pathways and airway remodelling. The second tier comprises an important airway‐related comorbidity/modifier, OSA, which does not share the same inflammatory pathophysiology but mechanically and clinically aggravates the burden of the core inflammatory diseases and frequently co‐occurs with them (Table 1 summarizes them). First, these diseases involve tight interactions between the upper and lower airways, supporting the unified airway hypothesis of shared inflammatory pathways and mutual influence. Second, each has high prevalence, substantial overlap with other airway conditions, and evidence of significant burden. Third, the evidence most strongly demonstrates that these conditions entail high direct and indirect costs and reduced quality of life. While it is recognised that other comorbidities (such as gastro‐oesophageal reflux disease, anxiety/depression, osteoporosis) may also co‐occur with airway diseases, we limit our active comorbidity screening within the GAU to this defined group because of their substantial prevalence and their relevance to a shared pathophysiology. By focusing on this set, we can standardise our workflow, streamline resources, and ensure that the unit addresses the most relevant airway comorbidities.

Table 1.

Diseases falling under the scope of GAUs.

Diseases falling under the scope of GAUs
Tier	Disease	Affected airway	Common comorbidities	Predominant inflammatory endotype	Main clinical guideline(s)
Tier 1	Allergic rhinitis	Upper airway	Asthma, rhinosinusitis, conjunctivitis, atopic dermatitis	T2	ARIA 2016—Allergic Rhinitis and its Impact on Asthma
Tier 1	Chronic rhinosinusitis (CRSwNP/CRSsNP)	Upper airway	Asthma, AERD, nasal polyposis, COPD	CRSwNP: T2 dominant/CRSsNP: T1, T3	EPOS 2020—European Position Paper on Rhinosinusitis and Nasal Polyps
Tier 1	Asthma (Type 2/Eosinophilic)	Lower airway	Allergic rhinitis, obesity, atopic dermatitis, OSA, COPD	T2‐high or T2 low	GINA 2025—Global Initiative for Asthma Management and Prevention
Tier 1	COPD	Lower airway	Cardiovascular disease, bronchiectasis, rhinitis, OSA	Mainly neutrophilic, but 20 − 40% with T2	GOLD 2026—Global Initiative for Chronic Obstructive Lung Disease
Tier 1	Bronchiectasis	Lower airway	Sinusitis/rhinosinusitis, rhinitis, COPD, asthma, recurrent infections, OSA	Mostly neutrophilic; some with T2	BTS 2019—British Thoracic Society Guideline for Bronchiectasis in Adults 2018
Tier 2	OSA	Upper airway	Obesity, COPD, asthma, rhinitis, hypertension, metabolic syndrome, heart disease	Not classified as T1 ‐ T3; primarily mechanical and ventilatory mechanisms	AASM 2019—American Academy of Sleep Medicine Guidelines SEPAR 2022 ‐ Consensus on obstructive sleep apnoea

Abbreviations: COPD, chronic obstructive pulmonary disease; CRSwNP, chronic rhinosinusitis with nasal polyps; CRSsNP, chronic rhinosinusitis without nasal polyps; GAU, global airways unit; OSA, obstructive sleep apnoea.

In summary, the burden of airway inflammatory diseases is vast, with high prevalence, significant impact on individuals and families, and substantial social and healthcare costs. By integrating care across the airway spectrum into a specialised GAU, we aim to identify disease earlier, treat comorbid airway conditions in a coordinated manner, reduce duplication of investigations and hospitalisations, improve patient reported outcomes, and ultimately reduce the economic and QoL burden associated with airway disease.

2. Materials and Methods

To develop this proposal, a multidisciplinary panel of experts in allergy, pulmonology, and otolaryngology was assembled based on predefined criteria including clinical experience, academic output, and involvement in guideline development. Beyond these criteria, panel composition was also planned to ensure a representation from different levels of care (university‐affiliated and community tertiary centres), and attention to gender balance among invited experts. The panel comprised 17 experts (4 allergists, 8 otolaryngologists, 5 pulmonologists) from 18 institutions. The group employed a structured consensus‐based approach, integrating evidence from international guidelines and key publications, followed by iterative discussions to define the GAU framework, diagnostic pathways, and care model. Specifically, consensus was developed using a modified Delphi method [19], a structured technique widely used to derive group consensus among experts when empirical trial data are limited, chosen over a face‐to‐face nominal group technique because it allowed asynchronous participation of geographically dispersed panel members. The process comprised one round of structured iteration (an initial item‐generation round followed by one further round of anonymous rating and revision); items were retained in the final framework when they reached a predefined agreement threshold of ≥ 80% of panel members rating them as appropriate [19]. Discussion minutes were kept for each round.

To that end, a structured, non‐systematic literature search was conducted in PubMed, Scopus, and Web of Science up to January 2026. Keywords included combinations of “unified airway”, “allergic rhinitis”, “asthma”, “chronic rhinosinusitis”, “COPD”, “bronchiectasis”, “multidisciplinary care,” and “integrated care models”. Searches were restricted to articles published in English or Spanish between January 2000 and April 2026, and titles/abstracts were independently screened by two reviewers, with disagreements resolved by discussion with a third panel member. Priority was given to international guidelines (e.g., ARIA, GINA, GOLD, EPOS), systematic reviews, and high‐impact clinical studies. Articles were selected based on relevance to airway multimorbidity, diagnostic strategies, and multidisciplinary care implementation. Because this was a narrative, consensus‐based synthesis rather than a question‐driven systematic review, a formal evidence‐grading framework such as GRADE or the Oxford Centre for Evidence‐Based Medicine levels of evidence was not applied; such frameworks are designed to grade the certainty of evidence for a specific clinical question than to support the design of an organisational care‐delivery model drawing on heterogeneous sources (guidelines, epidemiological data, and expert opinion). We acknowledge this as a methodological limitation, discussed further below.

Finally, we note explicitly that the design of the GAU framework, including all recommendations herein, was conducted independently of the panel members' individual relationships with pharmaceutical companies, and received no commercial funding, sponsorship, or content input from industry (see Conflicts of Interest).

3. Results

3.1. Scope of Diseases Included

In the design of the GAU, we propose to include a spectrum of conditions that span the anatomical airway continuum—from upper respiratory tract conditions to lower airway disease. Following the conceptual distinction introduced above, we separate these conditions into two tiers (Table 1): (i) core inflammatory unified airway diseases: AR, CRSwNP/CRSsNP, asthma (with particular emphasis on the type 2/eosinophilic endotype), COPD, and non‐cystic‐fibrosis bronchiectasis, which share overlapping type 2‐skewed or mixed inflammatory pathophysiology and airway remodelling mechanisms; and (ii) an important airway‐related comorbidity/modifier, OSA, which is not classified within the type 1–3 inflammatory endotype framework and is instead primarily driven by mechanical and ventilatory factors, but which substantially worsens the burden, comorbidity acquisition, and control of the core inflammatory diseases when it coexists with them. We adopt this two‐tier terminology specifically to avoid implying that OSA shares the type 2/eosinophilic inflammatory mechanism of the other conditions, while still retaining it within the GAU's active screening remit given its clinical relevance and frequent coexistence. This selection is grounded in the recognition that these conditions frequently co‐exist, share pathophysiologic mechanisms (especially type 2 inflammation and airway remodelling) and impose a substantial individual and system burden [2, 7]. The unit's remit, therefore, prioritises those airway diseases with high prevalence, well‐documented comorbidity, and shared pathophysiology across the airway. While we acknowledge that additional comorbidities (for instance, gastro‐oesophageal reflux disease, systemic conditions such as osteoporosis, or emotional disorders such as anxiety, depression, and chronic stress) may be present, the GAU focuses its active comorbidity screening on this defined set because it offers a practical and evidence‐based framework for integrated airway care.

Not all patients with airway disease require evaluation in a GAU. The model is primarily intended for patients with moderate‐to‐severe disease, multimorbidity (coexisting upper and lower airway conditions), poor disease control despite guideline‐based therapy, frequent exacerbations, or diagnostic uncertainty. In contrast, patients with mild, well‐controlled conditions (e.g., allergic rhinitis adequately managed with oral antihistamines alone) can typically be managed effectively in primary care or single‐specialty settings.

3.2. Positioning of the GAU Relative to Existing Multidisciplinary Models

Multidisciplinary care of airway disease is not a new concept: joint allergy‐ENT clinics, severe asthma MDTs, and CRS multidisciplinary clinics are already established in several centres and have demonstrated benefits including improved diagnostic accuracy, reduced exacerbations, optimisation of high‐cost biologic therapy, and reduced corticosteroid exposure [20, 21, 22]. What distinguishes the GAU from these precedents is its breadth and its structure: rather than being organised around a single index disease with secondary referral to other specialties when needed, the GAU is designed from the outset as a tri‐specialty entry point (allergy, ENT, pulmonology) for the full core inflammatory airway spectrum, with predefined essential/reserved diagnostic tiers, an explicit lead‐specialty assignment mechanism, and a structured follow‐up schedule applied irrespective of which disease triggered referral. Table 2 compares the GAU with existing multidisciplinary formats across these dimensions. This comparison illustrates that the GAU's incremental contribution lies not in the principle of multidisciplinary collaboration itself, which is well established, but in generalising and standardising that principle across the entire unified airway, rather than restricting it to a single disease entry point.

Table 2.

Positioning of the GAU relative to existing multidisciplinary airway models.

Dimension	Severe asthma MDT	CRS multidisciplinary clinic	Generic joint allergy‐ENT clinic	Global Airways Unit (GAU)
Entry point/target population	Severe, uncontrolled asthma	Refractory/recurrent CRS, mainly pre‐ or post‐surgical (2)	Patients with combined upper‐airway and allergic symptoms	Any of the core inflammatory airway diseases, or diagnostic uncertainty across them, evaluated jointly from first referral
Specialties routinely involved	Pulmonology ± specialist nurse/allergy	ENT ± allergy	Allergy + ENT	Allergy + ENT + pulmonology as a fixed core team
Eligibility criteria	Disease‐severity thresholds for the index disease	Endoscopic/CT‐defined refractory disease	Variable, institution‐dependent	Moderate‐to‐severe, multimorbid, poorly controlled, frequently exacerbating, or diagnostically uncertain airway disease (any core diagnosis)
Lead‐specialty assignment	Implicit (pulmonology)	Implicit (ENT)	Not formally defined	Explicit, assigned after joint intake based on dominant phenotype/comorbidity burden
Diagnostic structure	Asthma‐specific work‐up	Sinonasal work‐up (endoscopy ± CT)	Variable	Predefined two‐tier essential/reserved pathway spanning upper and lower airway, with trigger criteria (Tables 3, 4)
Follow‐up protocol	Variable, often asthma‐outcome‐focused	Variable	Variable	Standardised: 6‐month initial review, then annual if stable, with predefined outcome metrics

3.3. Diagnostic Panel

Our proposed diagnostic panel for the GAU adopts a tiered approach to maximise efficiency while ensuring comprehensiveness: all patients will undergo a core set of “essential“ investigations in order to confirm diagnosis and define airway involvement, while a second set of “reserved” investigations is deployed when diagnostic uncertainty persists or more precise endotype/phenotype classification is required. In practice, essential investigations include nasal endoscopy (or rhinoscopy) and spirometry with bronchodilator testing, as well as skin‐prick testing and/or serum‐specific IgE when AR is suspected or fractional exhaled nitric oxide (FeNO) for the assessment of type 2 inflammation or confirmation of the asthma diagnosis. Chest radiography is included for patients with lower airway symptomatology, in patients exhibiting a smoking habit of more than 10 packs per year and/or displaying abnormal spirometric values, and sinus computed tomography is reserved for those with sinus disease red‐flags or pre‐surgical planning.

Although defined as “essential”, these investigations are not intended to be universally applied to every patient. Instead, they represent a core diagnostic toolbox from which tests are selected based on clinical presentation and pre‐test probability. Table 3 includes a dedicated “trigger criteria/applicable population” column specifying the clinical indication for each test. This flexible approach ensures that investigations are tailored to individual patient characteristics, thereby avoiding unnecessary testing and optimising resource utilisation.

Table 3.

Essential Investigations.

Essential Investigations (First line)
Area	Investigation	Purpose	Trigger criteria/applicable population	Approx. relative cost/diagnostic value
Upper airway	Nasal endoscopy or anterior rhinoscopy	Identify nasal polyps, mucosal oedema, purulence, rhinorrhoea, deviated septum, and nasopharynx evaluation	Patients with upper‐airway symptoms or suspected CRS/AR	Low cost; gold‐standard diagnostic yield for CRS
	Skin prick testing, radioallergosorbent test or serum‐specific IgE (in patients with suspected allergic rhinitis)	Confirm allergic sensitization	Suspected AR, or atopic phenotype driving lower‐airway disease	Low‐to‐moderate cost; high specificity for sensitization
Lower airway	FeNO (Fractional exhaled nitric oxide)	Assessment of type 2 inflammation/asthma diagnosis	Suspected asthma, or phenotyping prior to biologic candidacy	Low‐moderate cost; moderate accuracy for eosinophilic asthma
	Spirometry with bronchodilator response	Diagnose obstructive pattern, assess reversibility (asthma/COPD)	Any patient with lower‐airway symptoms or smoking history	Low cost; high sensitivity/specificity for obstruction
Sleep questionnaires	Sleep questionnaire (e.g., STOP‐BANG, Epworth Sleepiness Scale, SNOT‐22, and Pittsburgh Sleep Questionnaire)	Screen for OSA suspicion. Refer if positive.	All GAU patients as part of joint intake, given the high background prevalence of OSA comorbidity	Negligible cost; screening tool only, not diagnostic

Should the initial assessment leave ambiguity regarding the type of inflammation (e.g., neutrophilic vs eosinophilic) or the presence of structural airway disease, reserved investigations are introduced: peripheral blood eosinophil count for type 2 inflammatory profiling [23, 24, 25] induced sputum cell counts or microbiologic analysis in presence of symptoms suggestive of bronchiectasis or frequent‐exacerbator cases; high‐resolution chest CT for structural airway evaluation; and respiratory polygraphy or full polysomnography when OSA is under consideration. This tiered structure allows resource‐sparing while ensuring that more advanced diagnostics are applied only when clinically indicated.

The selected diagnostic tests are supported by well‐established performance characteristics. For instance, spirometry with bronchodilator response demonstrates high sensitivity and specificity for obstructive airway disease, while FeNO provides a non‐invasive marker of type 2 inflammation with moderate diagnostic accuracy for eosinophilic asthma [20]. Similarly, nasal endoscopy remains the gold standard for CRS diagnosis. From a health‐economic perspective, the tiered approach is designed to improve cost‐effectiveness by prioritising high‐yield, low‐cost investigations and reserving advanced imaging or specialised tests for selected cases. This strategy aims to reduce unnecessary testing, minimise duplication, and optimise resource allocation, which are key drivers of cost savings in integrated care models. Tables 3 and 4 include an approximate relative‐cost category for each investigation, alongside its principal diagnostic yield.

Table 4.

Reserved investigations.

Reserved Investigations (If diagnosis remains unclear)
Area	Investigation	Indication	Approx. relative cost/incremental value
Upper airway	Nasal cytology/Blood eosinophil count	Assist with phenotyping in recurrent CRS or treatment failure	Low‐moderate cost; incremental value mainly for biologic candidacy discussions
	Paranasal sinus CT	In unclear CRS diagnosis despite endoscopy, or pre‐surgical planning	Moderate‐high cost; high incremental value when endoscopy is inconclusive
Lower airway	Chest X‐ray	Rule out alternative diagnoses or structural abnormalities	Low cost; low specificity, mainly used to exclude alternative pathology
	Blood eosinophil count	Phenotyping of asthma/COPD for endotype‐specific management	Low cost; moderate incremental value for T2‐targeted therapy selection
	Induced sputum cell count	Assessment of type 2 inflammation	Moderate cost; high incremental value but limited availability
	Sputum culture	Indicated in patients with symptoms suggestive of bronchiectasis and/or frequent exacerbations of infectious nature	Low‐moderate cost; high incremental value for antibiotic stewardship
	High‐resolution CT chest	If bronchiectasis, interstitial lung disease, or small airway involvement is suspected	High cost; high incremental diagnostic value, reserved for selected cases
Sleep related	Overnight oximetry/polysomnography	If OSA is suspected by screening questionnaire and clinical symptoms	Moderate (oximetry) to high (polysomnography) cost; polysomnography remains diagnostic gold standard

3.4. Referral, Discharge, and Step‐Down Criteria

To operationalise patient stratification, we propose the following explicit, structured criteria (rather than narrative description alone):

• Referral to GAU is indicated when one or more of the following are present: (i) coexistence of confirmed or strongly suspected upper and lower airway disease; (ii) poor disease control despite ≥ 3 months of guideline‐concordant therapy for the index condition; (iii) ≥ 2 exacerbations/year of the index condition; (iv) diagnostic uncertainty regarding the predominant inflammatory endotype or the presence of an unrecognised comorbidity; or (v) candidacy for biologic therapy, where confirmation of phenotype/endotype across the airway is required.

• Discharge/step‐down to single‐specialty or primary care follow‐up is appropriate once: (i) the diagnosis and predominant endotype are established and a lead specialty has been assigned; (ii) disease control is achieved and maintained for ≥ 6 months on stable therapy; and (iii) no further multidisciplinary input is anticipated for comorbidity management, with re‐referral pathways kept open should control deteriorate.

• Patients with mild, single‐organ, well‐controlled disease (e.g., intermittent AR responsive to oral antihistamines) should not be referred to the GAU and are managed in primary care or single‐specialty settings, as previously stated.

These criteria are intended as a starting decision framework; we anticipate refining them into a formal algorithm once pilot implementation data are available (see Discussion).

3.5. Interdisciplinary Care Model

Primary care physicians play a key role in the early identification of patients who may benefit from GAU referral. Screening should include recognition of persistent or poorly controlled airway symptoms, coexistence of upper and lower airway complaints, frequent exacerbations, or suboptimal response to standard therapy. The use of simple tools such as symptom checklists and validated questionnaires (e.g., asthma control tests, rhinitis scores, or sleep questionnaires) may help identify patients requiring multidisciplinary evaluation.

The model does not assume that all specialists independently manage the full spectrum of airway diseases. Instead, it relies on structured collaboration, where initial assessment is complemented by multidisciplinary review. This reduces the risk of misclassification or missed alternative diagnoses, particularly in complex presentations such as dyspnoea, where pulmonary, upper airway, and systemic causes must be considered.

The GAU's workflow (Represented in Figure 1) begins in the primary care or specialty clinic setting, where patients with upper airway or lower airway symptoms (as detailed in Table 5) are identified. Referral is then made to the GAU, where allergists, otolaryngologists, and pulmonologists conduct a joint intake: a detailed clinical history is taken, a comprehensive physical examination is performed, and essential/reserved investigations are ordered (Table 3 and Table 4). Following completion of these studies, the multidisciplinary team convenes to confirm the diagnosis of one or more of the target airway diseases, assess airway phenotype/endotype, and map relevant comorbidities. Subsequently, targeted comorbidity screening is undertaken (tailored to the primary diagnosis) for instance, sinus evaluation in asthma, sleep‐disordered breathing in upper airway disease, aspirin‐exacerbated respiratory disease (AERD) in CRS/asthma and emotional disorders such as anxiety, depression, and chronic stress. Following the establishment of diagnosis and comorbid profile, the unit assigns a lead specialty (allergy, ENT, or pulmonology) for each patient and institutes a monitoring plan with scheduled reviews 6 months initially and annually thereafter if stable. Outcomes monitored include lung function metrics, QoL and disease‐specific questionnaires, exacerbation frequency, and biomarkers (where relevant). This integrated model (anchored in the unified airway concept) intends to break down the silos of sub‐specialty care, facilitate earlier detection of comorbidity, optimise diagnostics, and streamline patient pathways [7, 26].

Figure 1.

Global airways unit operational algorithm.

Table 5.

Clinical suspicion based on key signs and symptoms.

Clinical suspicion based on key signs and symptoms
Disease	Signs and symptoms
Allergic rhinitis	Sneezing, nasal itching, rhinorrhea, nasal obstruction, ocular symptoms like itch, redness or tearing; symptoms often seasonal or triggered by exposure to allergens (e.g., dust, pollen)
CRSwNP	Smell dysfunction (hyposmia/anosmia) as leading symptom, nasal obstruction/congestion, nasal secretions (rhinorrhoea and/or postnasal drip), and facial pain/headache; presence of bilateral visible polyps on nasal endoscopy. Symptoms persist > 12 weeks
CRSsNP	Similar to CRSwNP but without visible polyps; nasal obstruction and facial pressure predominate, characteristic mucopurulent nasal discharge.
Asthma (type 2/eosinophilic predominant)	Episodic wheezing, shortness of breath, chest tightness, cough; often worse at night or with exercise. May co‐occur with rhinitis; history of atopy common. Symptoms often improve with bronchodilators.
COPD	Persistent dyspnea, activity limitation and/or cough with or without sputum production. Patients may experience acute respiratory events characterized by exacerbations.
Bronchiectasis	Chronic productive cough, frequent respiratory infections, hemoptysis, or crackles on auscultation; may coexist with asthma or COPD. History of repeated antibiotics often present.
OSA	Snoring, observed apnoeas, excessive daytime sleepiness, irritability, insomnia; often associated with obesity, hypertension or cardiopulmonary comorbidities, ictus, or nasal obstruction.

Abbreviations: CRSsNP, chronic rhinosinusitis without nasal polyps; CRSwNP, chronic rhinosinusitis with nasal polyps; COPD, chronic obstructive pulmonary disease; OSA, obstructive sleep apnoea.

3.6. The Central Role of Otolaryngology Within the GAU

Although the GAU is by design a tri‐specialty model, otolaryngology occupies a structurally central position. First, nasal endoscopy performed by the otolaryngologist constitutes the diagnostic gold standard for CRSwNP/CRSsNP and is the single investigation in the essential panel capable of directly visualising the upper‐airway inflammatory phenotype (polyp burden, mucosal oedema, purulence) that anchors much of the unified‐airway hypothesis [2, 7]. Second, ENT assessment is frequently the first point at which red‐flag, alternative, or coexisting upper‐airway diagnoses (e.g., unilateral disease, structural abnormality, suspected malignancy) are identified, with direct implications for the safety of the overall diagnostic pathway. Third, the otolaryngologist is typically best placed to evaluate and coordinate OSA‐related upper‐airway structural contributors (e.g., septal deviation, turbinate hypertrophy, adenotonsillar disease) that interact with the GAU's lower‐airway and inflammatory work‐up. Fourth, in patients being considered for biologic therapy for severe CRSwNP or comorbid type 2 disease, the otolaryngologist's longitudinal endoscopic monitoring provides an objective, reproducible outcome measure that complements pulmonary‐function and patient‐reported metrics used by allergy and pulmonology. For these reasons, while lead‐specialty assignment within the GAU is phenotype‐driven, otolaryngology input is essential for any patient in whom upper‐airway involvement is suspected or confirmed.

3.7. Expected Impact

The proposed integrated consultation model seeks to dismantle the fragmentation of care for patients with CRDs, particularly in resource‐constrained settings. By facilitating early intervention and adopting a unified perspective on airway disease, the model aims to reduce the progression towards more severe forms of the underlying disease or its comorbidities [3, 7]. In addition, it seeks to optimise resource use by minimising repeated studies and unnecessary referrals, thereby enhancing clinical efficiency. Several health economic analyses across CRDs demonstrate substantial direct medical costs (hospitalisations, medications) and sizable indirect costs (lost productivity), supporting the rationale for interventions that reduce exacerbations and improve disease control [13, 14, 18]. The unified clinical vision may also improve treatment adherence by presenting patients with a coordinated care strategy rather than disjointed specialty visits. Finally, by producing a replicable, evidence‐based model, the GAU could be adapted across diverse clinical settings and health system contexts, thereby broadening its potential impact and sustainability.

4. Discussion

This manuscript presents a conceptual and practice‐informed model for the implementation of a GAU, rather than a report of a single‐centre experience. This group understand that multidisciplinary collaboration around airway disease is an established principle: severe asthma MDTs, CRS multidisciplinary clinics, and joint allergy‐ENT services already exist and have demonstrated clinical benefit [20, 21, 22]. The contribution of this work is therefore the standardisation of that principle into a single, reproducible, tri‐specialty model spanning the entire core inflammatory airway spectrum, with an explicit two‐tier diagnostic pathway, a defined lead‐specialty assignment mechanism, and predefined follow‐up and referral/discharge criteria (Table 2), elements that, to our knowledge, are not jointly specified in existing single‐disease multidisciplinary formats.

Although some authors have implemented elements of multidisciplinary airway care in their respective institutions, the framework proposed here reflects a consensus‐derived model intended for broader applicability. The structure of the GAU was developed through expert consensus, informed by existing multidisciplinary care models, guideline recommendations, and clinical experience across different healthcare settings.

The author group includes clinicians from different institutions and healthcare systems, ensuring that the proposed model is not limited to a single institutional workflow but is adaptable to diverse clinical environments.

The GAU model offers a practical translation of the unified airway concept into a clinic‑based pathway prioritising early comorbidity detection, phenotype identification, and resource optimisation. It presents several potential advantages. First, early detection of comorbid upper or lower airway disease may permit more complete inflammation control and fewer exacerbations [8]. Second, phenotype/endotype‐based care (Type 2 vs. neutrophilic) becomes more practical when allergists, ENTs, and pulmonologists collaborate [20]. Third, resource efficiency: an integrated clinic may reduce diagnostic duplication and streamline care pathways. Fourth, by addressing economic burden: reducing exacerbations, hospitalisations, and productivity loss, the GAU could generate cost‐savings across individuals and systems. Published multidisciplinary models in respiratory care provide precedent for improved outcomes with integrated services [26, 27]. Implementation, however, requires institutional support (joint clinic space and shared electronic records), and prospective data are necessary to document the benefits of the outcome.

Translating the GAU from a conceptual framework into routine practice, particularly within public hospital systems, will encounter institutional barriers that merit explicit discussion. Departmental cost‐center accounting commonly attributes activity and revenue to a single referring specialty, creating disincentives for joint consultations in which workload and outcomes are shared across allergy, ENT, and pulmonology; this can be partially mitigated by negotiating a shared activity code or block‐funded joint clinic slot at the outset, rather than retrofitting funding after implementation. Conflicting outpatient scheduling systems across departments represent a further practical obstacle, since a true joint intake requires simultaneous appointment slots across three specialties; a pragmatic facilitator is to begin with a single weekly joint‐clinic slot rather than attempting full‐scale rollout, expanding capacity once workflow is validated. Disputes over performance‐based compensation distribution among specialties can be reduced by predefining, in advance and in writing, how joint‐consultation activity is credited to each participating department. Finally, non‐interoperable electronic medical record (EMR) platforms are a well‐documented and frequently underestimated barrier to integrated care more broadly: a scoping review of EMR/EHR implementation identified resource constraints, insufficient technical/educational support, and poor workflow integration across professional groups as recurring barriers to adoption [28], while organisational barriers such as unclear governance and lack of clinical leadership have similarly been identified as obstacles to client‐ and professional‐shared electronic records [28]. Pending full EMR interoperability, a shared structured intake/outcomes form can serve as an interim facilitator for data continuity across specialties.

Based on these considerations, we propose a phased implementation roadmap: (Phase 1) establishment of a single joint clinic slot at one pilot centre, using existing staff and a shared paper or spreadsheet‐based intake form, to validate workflow and referral criteria; (Phase 2) formal allocation of a shared activity/funding code and expansion to weekly or twice‐weekly joint sessions, with prospective collection of the outcome metrics proposed in the Conclusion; (Phase 3) integration of the GAU intake/outcome dataset into the institutional EMR (or a bridging structured data tool) to enable systematic, multicentre data pooling; and (Phase 4) multicentre roll‐out informed by the pilot data, with adaptation of eligibility and follow‐up criteria as local evidence accrues. We consider this phased approach, rather than simultaneous full‐scale implementation, the most realistic path given the institutional barriers outlined above.

This group recognises that this manuscript is a descriptive proposal and that empirical evidence from a functioning GAU is currently lacking. The absence of prospective, real‑world data from an operational GAU represents a weakness of the present work. Establishing pilot GAUs with systematically collected outcome and health‑economic metrics is the immediate next step planned by our group to validate the clinical effectiveness, QoL benefits, and cost‑savings hypothesised here.

In this context, and looking to the near future, the implementation of these units could benefit from existing technologies, such as telemedicine, to streamline processes, including initial interviews with nursing staff, review and follow‐up interviews, among others. Similarly, implementing artificial intelligence (AI) to unify clinical information and process data in clusters for statistical and research purposes may be the next logical step towards a unified data collection and analysis system.

4.1. Strengths and Limitations

This manuscript has several strengths. It proposes a clinically applicable and structured model to operationalise the global airway concept, integrating current guideline recommendations with expert consensus across allergy, pulmonology, and otolaryngology. The framework emphasises pragmatic elements such as a tiered diagnostic approach, multidisciplinary collaboration, and resource optimisation, making it adaptable to different healthcare settings. In addition, it addresses an important gap between theoretical concepts of airway multimorbidity and their real‐world clinical implementation.

However, several limitations should be acknowledged. First, this is a consensus‐based proposal supported by a structured but non‐systematic literature review, which may introduce selection bias; we did not apply a formal evidence‐grading framework such as GRADE, which limits formal appraisal of the certainty of the underlying evidence. Second, the model has not yet been validated in prospective real‐world settings, and therefore its clinical effectiveness and cost‐effectiveness remain to be demonstrated; the relative‐cost categories presented in Tables 3 and 4 are approximate and not derived from a formal health‐economic analysis. Third, while the framework aims to optimise resource utilisation through a triage‐based and flexible diagnostic approach, implementation challenges may impact feasibility. Finally, the proposed model does not apply to all patients with airway disease, but rather targets those with more complex, uncontrolled, or multimorbid conditions.

5. Conclusion

A GAU integrates diagnostics and specialty expertise across the airway continuum to improve early detection of comorbidity, enable phenotype‑driven management, and potentially reduce healthcare and societal costs. We recommend pilot implementation of this model, with outcome evaluation including time‐to‐diagnosis of comorbid disease, exacerbation frequency, healthcare utilisation, and patient‐reported outcomes. Further research should assess cost‐effectiveness and refine phenotype/endotype pathways across airway diseases.

Author Contributions

All the authors have made substantial contributions to the conception or design of the work, the acquisition, analysis, and interpretation of data for the work. They have drafted the work and revised it critically for important intellectual content, have provided approval for publication of the content, and have agreed to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Funding

The authors have nothing to report.

Ethics Statement

The authors have nothing to report.

Conflicts of Interest

D.M.C.: Serves as Academic Manager at the European Forum for Research and Education in Allergy and Airway Diseases (EUFOREA) and as Review Editor at Frontiers in Allergy, Rhinology Section. E.J.C.: No conflicts of interest related to this initiative. A.D.C.: Consulting fees from AstraZeneca, Sanofi/Regeneron, GSK, MSD, Menarini, and Meda. Payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events from AstraZeneca, Sanofi, GSK, MSD, Regeneron, Menarini, and Meda. Payment for expert testimony from Sanofi, GSK, AstraZeneca, and Menarini. Support for attending meetings and/or travel from Sanofi, Menarini, and FAES. Current president at the Commission on Rhinology, Allergy and Anterior Skull Base of the Spanish Society of Otolaryngology and Head and Neck Surgery. J.D.A.: No conflicts of interest related to this initiative. F.J.A.: Declares that he has received fees in recent years for consulting work, lecturing, attending conferences and scientific meetings, and receiving materials from AstraZeneca, Chiesi, GlaxoSmithKline, Menarini, Orion Pharma, and Sanofi/Regeneron. R.C.C.: No conflicts of interest related to this initiative. S.C.: Received fees as a speaker for GSK, Astra Zeneca, Novartis, Chiesi, and Sanofi. R.C.M.: No conflicts of interest related to this initiative. A.G.F.: Declares that in the last 3 years has received fees for lectures, attendance at meetings, research grants and consultancy from Astra‐Zeneca, Chiesi, Gebro, GSK, Menarini and Sanofi. D.P.C.: No conflicts of interest related to this initiative. F.P.G.: Has received fees in the last year for giving presentations for GSK, Astra‐Zeneca, Sanofi‐Regeneron, Gebro, and Menarini. A.E.R.: No conflicts of interest related to this initiative. M.A.R.: Collaborations with AstraZeneca, GSK, Chiesi and Menarini. M.S.: Speaker for Sanofi and Glaxo. J.G.S.: No conflicts of interest related to this initiative. R.B.S.: No conflicts of interest related to this initiative. J.M.S.: No conflicts of interest related to this initiative.

Data Availability Statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.