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Rectifying COPD management: A critical analysis
of the GOLD strategy
Kwang Joo Park
Please cite this article as: Park KJ. Rectifying COPD management: A critical analysis of the
GOLD strategy. ERJ Open Res 2025; in press (https://doi.org/10.1183/23120541.01059-2025).
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Review
Rectifying COPD management: A critical analysis of the GOLD strategy
Kwang Joo Park
Department of Pulmonology and Critical Care Medicine, Ajou University School of Medicine,
Suwon, South Korea
Correspondence author: Kwang Joo Park (parkkj@ajou.ac.kr)
Author Contribution: KJP confirms sole responsibility for all aspects of this review article,
including the conception, literature search, writing, and final approval of the manuscript .
Funding: The author has not declared a specific grant for this research from any funding agency
in the public, commercial or not-for-profit sectors.
Competing interests: None declared.
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Abstract
The Global Initiative for Obstructive Lung Disease (GOLD) has greatly contributed to the
management of chronic obstructive pulmonary disease (COPD). However, several important
issues persist. The initial conception of chronic bronchitis as a short-term illness caused by
1950s air pollution differs significantly from the current understanding of COPD. COPD and
asthma are often diagnosed subjectively due to the lack of definitive diagnostic criteria. Asthma
patients who lack classic features may be misclassified as having chronic bronchitis,
contributing to diagnostic overlap and unnecessary heterogeneity. The inclusion of asthma
patients in COPD studies may have introduced significant bias, leading to misguided
management recommendations. Notably, studies that attempted to minimize asthma
misclassification—such as by excluding patients with elevated blood eosinophil counts—
demonstrated more favourable outcomes in the absence of inhaled corticosteroids compared to
studies that applied no such exclusion criteria. COPD patients with blood eosinophilia respond
to inhaled corticosteroids precisely because they likely have asthma. Bronchodilator
reversibility and airway hyperresponsiveness tests have limited utility in ruling out asthma.
Despite their limitations, lung function tests remain central to the assessment and management
of COPD. Their clinical value is limited by measurement variability and controversies
regarding their interpretation. The current “combined assessment” tool may have limited
validity, particularly as treatment strategies have become increasingly standardized,
emphasising early initiation of dual bronchodilators and avoidance of corticosteroids. Existing
strategy documents remain subject to future revisions, as has occurred with previous versions.
Realising their full potential requires critical engagement and thoughtful revision, particularly
in addressing persistent areas of controversy.
Keywords: Chronic obstructive pulmonary disease; asthma; global initiative for obstructive
lung disease; GOLD reports; combined initial assessment; lung function tests.
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Introduction
Chronic obstructive pulmonary disease (COPD) is one of the greatest burdens and health
threats worldwide [1]. COPD management is challenging due to its chronic, irreversible
progression, frequent exacerbations, and limited treatment responses [2]. The Global Initiative
for Obstructive Lung Disease (GOLD) was established in 1997 to improve awareness and
standardize COPD diagnosis and treatment [3].
The development of effective inhaled drugs and combinations thereof for COPD treatment is
promising [4]. For nearly 30 years, the freely accessible, annually updated GOLD reports have
guided clinicians [5]. Since their initial issuance, significant revisions have been made,
particularly regarding severity grading for optimal treatment, combination drug strategies, and
the role of corticosteroids [3, 5-9].
Given the frequent revisions, further changes are expected [5, 6, 9, 10]. The current strategy
document should not be viewed as definitive. Ensuring effective future COPD management
through the GOLD strategy will require ongoing constructive feedback and collaborative
refinement. Although critical perspectives regarding these issues exist, these perspectives have
not resulted in adequate changes to the GOLD reports [11-13]. A comprehensive evaluation of
current and potential issues is necessary to maintain their relevance. This review does not
intend to negate the importance of the GOLD reports. Rather, it aims simply to open a
discussion on issues that could be considered to improve the understanding and management
of COPD.
The COPD–asthma overlap: Diagnostic challenges and therapeutic implications
Diagnosing COPD and asthma is challenging due to their overlapping clinical features and
symptoms, and the lack of clearly defined diagnostic criteria for both [14, 15]. Despite
extensive research on, and development of, inhaled drugs over the past 50 years [4, 5, 10],
accurate differentiation between COPD and asthma remains a crucial prerequisite for valid
clinical studies. Inclusion of undiagnosed asthma patients in COPD cohorts may significantly
bias research outcomes.
While inhaled corticosteroids (ICS) are a cornerstone of asthma management , their role in
COPD is controversial and has diminished [2, 16]. However, corticosteroids remain a
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significant component of COPD treatment, particularly during acute exacerbations [2]. This
apparent inconsistency in corticosteroid efficacy may stem, in part, from the ambiguous
diagnostic criteria for COPD and asthma.
Diagnosing asthma remains inherently subjective due to the absence of a definitive diagnostic
gold standard. In COPD treatment research, excluding asthma is crucial, yet challenging.
COPD clinical studies often use the criterion “prior history of asthma or current diagnosis of
asthma” to exclude patients with asthma, and yet that diagnosis of asthma may depend on
subjective physician assessment [17-21]. Asthma is frequently underdiagnosed and
misdiagnosed due to various physician and patient factors [22, 23].
Although the diagnostic criteria for COPD are generally more detailed than those for asthma
in clinical studies, comprehensive and standardized definitions are still lacking [24]. The
definition of emphysema remains largely restricted to pathological findings, with limited
attention to its clinical manifestations [25]. Similarly, the current definition of chronic
bronchitis is impractical, and no clinically applicable diagnostic criteria have been established
for nearly 70 years [3, 10, 25, 26]. Despite these limitations, COPD diagnosis primarily relies
on spirometric thresholds [10].
Although the diagnostic limitations of both COPD and asthma are recognized, they are often
frequently overlooked due to the perceived lack of immediate solutions. However, this
“elephant in the room” situation can no longer be tolerated, given the seriousness of these
diseases. The foundation of COPD management efforts will be threatened if these issues remain
unaddressed. While immediate solutions may be elusive, these problems must be
acknowledged and addressed. Clinical investigators and physicians have a responsibility to
ensure that pharmaceutical advancements translate into improved patient outcomes.
Salient features of asthma are well-established and used for diagnosis. The Global Initiative for
Asthma (GINA) guideline describes characteristic symptoms, clinical history, and spirometry
findings to support asthma diagnosis [27]. Although these criteria are designed to enhance
diagnostic accuracy, they may paradoxically hinder it. Asthma is characterized by considerable
clinical heterogeneity, and typical features or supportive test results are not consistently
observed in all patients [28].
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Symptom and obstructive-lung-function reversibility is a hallmark of asthma. However,
reversibility tests have low sensitivity, and full reversibility may be complicated by factors
such as long-standing, severe, poorly controlled, and non-allergic asthma [29, 30].
Bronchodilator reversibility (BDR) tests yield positive results in < 20% of asthma patients [31].
Notably, BDR rates of 18.4% have been reported in COPD patients, compared to 17.3% in
subjects with asthma [32], and nearly two-thirds of patients with moderate-to-very-severe
COPD tend to have positive BDR results [33].
Airway hyperreactivity (AHR) provocation tests are considered sensitive and specific for
asthma, but in white Americans, sensitivity of 69% was reported, and was as low as 52% in
non-atopic asthma [34]. Furthermore, more than 25% of COPD patients exhibit positive AHR
[35]. Methacholine challenge test results vary with technical factors, and interpretation is
controversial due to a wide borderline range [36]. BDR and AHR positivity rates in asthma
may be even lower when underdiagnosed cases are taken into account [22]. Considering these
limitations, the clinical utility of BDR and AHR assessments is likely overestimated [28].
As corticosteroids were recognized to be of limited utility and to have potential
adverse effects, including pneumonia, researchers explored reducing or discontinuing their use,
while emphasising the emerging dual bronchodilator combination of long-acting beta-agonist
(LABA) and long-acting muscarinic antagonist (LAMA) [19].
To clarify the role of ICS in COPD, numerous global studies have been conducted. However,
the results were potentially influenced by the inclusion of asthma patients in COPD cohorts.
Some studies attempted to exclude asthma based on participants’ blood eosinophil counts,
revealing significant outcome differences. The landmark FLAME study that directly compared
LABA/LAMA and ICS/LABA for exacerbation prevention, surprisingly demonstrated
superior outcomes without ICS [19]. That study excluded patients with a history of asthma and
blood eosinophil counts exceeding 600 cells/µL. A prior study, LANTERN, using the same
blood eosinophil criteria, also showed LABA/LAMA superiority [37]. The SUNSET study
found no exacerbation risk after ICS withdrawal from triple therapy in COPD patients with
similar blood eosinophil exclusion criteria [38]. Only the AFFIRM study, which lacked
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statements regarding specific asthma exclusion strategies, showed comparable exacerbation-
protective effects for LABA/LAMA without ICS [39].
The large-scale WISDOM study evaluated the consequences of gradual ICS withdrawal from
triple therapy in COPD patients [20]. While not employing blood eosinophil criteria, it found
no increased exacerbation risk after de-escalation to LABA/LAMA. However, a rescue
procedure that allowed ICS addition at the physician’s discretion may have filtered out some
asthma patients from the final analysis. The unexpected significant decrease in forced
expiratory volume in 1 second (FEV1) after ICS withdrawal may reflect the influence of
remaining asthma patients. Single-inhaler triple therapy (SITT) with ICS/LABA/LAMA was
developed and popularized for both COPD and asthma management. Several large studies have
evaluated SITT against other drug combinations, comparing inhaler regimens with and without
ICS [17, 18, 21, 40]. However, those studies did not specifically implement asthma-exclusion
procedures, such as blood eosinophil criteria, and consistently failed to replicate the
exacerbation prevention efficacy of dual bronchodilators without ICS seen in earlier studies
like FLAME. Recent real-world studies have been conducted that evaluated SITT in COPD
[41, 42]. In these settings, asthma-patient inclusion is less of a concern, as clinicians are more
likely to prescribe ICS-containing inhaler combinations. Additionally, patients who experience
inappropriate or undesirable drug effects may withdraw from the cohort.
Notably, both real-world and controlled SITT studies have consistently demonstrated that ICS-
responsive patients exhibit blood eosinophilia. However, such COPD patients may in fact have
undiagnosed asthma. Their exclusion based solely on a lack of a prior asthma diagnosis, one
that often relies on subjective assessment, is questionable. Blood eosinophilia and
corticosteroid responsiveness are characteristic features of asthma, while COPD, including
emphysema, lacks a clear pathogenic or pathophysiologic explanation for eosinophilia [43].
Some ambiguous conditions such as cough-variant asthma, asthma-COPD overlap syndrome,
and eosinophilic bronchitis, which may be asthma, are often misclassified due to an incomplete
presentation of classic asthma features. Although the above analyses suggest that the inclusion
of asthma may have influenced study outcomes, further studies are needed to distinguish
definitively between misdiagnosed asthma and the eosinophilic phenotype of COPD.
Given the issues outlined above, the potential inclusion of asthma patients in COPD trial
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populations may undermine the accurate evaluation of ICS in COPD. Additionally, biologics,
which have become integral to asthma management [44], have shown promise in selected
COPD patients, particularly those with eosinophilia [45-47]. However, their apparent
effectiveness in COPD may be confounded by the inclusion of asthma patients within COPD
cohorts. Therefore, concerted efforts are needed to derive more robust criteria for
differentiating asthma from COPD, thereby ensuring the validity of appropriate therapeutic
strategies.
Despite declining smoking rates, the incidence of COPD has not decreased [1]. This
phenomenon may be partly attributed to the long latency period of COPD, which typically
requires decades of exposure, as well as to other contributing risk factors, including air
pollution [2]. Furthermore, the inclusion of the asthma patients lacking classic features,
misdiagnosed as having chronic bronchitis, may also account for this observation. Regardless,
if factors unrelated to smoking are increasingly contributing to COPD development, current
COPD studies, which typically use a “more than 10 pack-years of smoking history” inclusion
criterion, should be reconsidered so that, in future studies, the COPD population may be
represented more accurately.
Questionable origins of chronic bronchitis
The identification and characterization of chronic bronchitis primarily originated in the United
Kingdom during the 1950s, remaining largely unknown elsewhere. This phenomenon has been
linked to severe air pollution associated with industrialization, excessive coal use, and specific
meteorological conditions, all occurring in the absence of effective environmental controls,
particularly during the 1952 Great Smog [48-51]. At that time, chronic bronchitis was
considered a short-term illness characterized by toxic inflammation of the respiratory tract or
exacerbation of pre-existing respiratory conditions. The event resulted in widespread
respiratory distress, with over 12,000 deaths and 150,000 hospitalizations. The British Medical
Research Council (MRC) established the Air Pollution Unit to assess and manage this public
health crisis [26]. The MRC played a pivotal role in developing and administering
comprehensive questionnaires to evaluate the affected population [52]. This effort led to the
widely accepted definition of chronic bronchitis as “the presence of a chronic productive cough
and sputum production for ≥ 3 months out of a year for a 2-year period” [52, 53]. However,
this traditional definition is difficult to apply in clinical practice, and a more practical, clinically
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applicable definition remains to be established.
At the 1958 CIBA Guest Symposium, efforts were made to define and classify chronic
obstructive respiratory diseases [25]. British representatives played a pivotal role in
establishing chronic bronchitis as a major component of what was then termed as chronic non-
specific lung disease, alongside asthma and emphysema. At the time, participants from other
countries were unfamiliar with the clinical utility of chronic bronchitis [25, 54]. Subsequently,
emphysema and chronic bronchitis were combined to form COPD, whereas asthma was
categorized separately. This historical progression has likely had a lasting influence on current
concepts of disease classification and clinical characterization. However, the chronic bronchitis
of that era differed significantly from the current understanding of COPD. While air pollution
can contribute to COPD, the underlying pathophysiology is distinct from the long-term,
irreversible structural damage now associated with COPD [2]. A study that used questionnaires
to evaluate and validate the definition of chronic bronchitis focused on postal workers exposed
to high levels of air pollution. However, it did not report specific measures to exclude asthma
and emphysema, nor did it adequately address smoking as a contributing factor [52]. The
historical context remains poorly understood within the respiratory community. When chronic
asthma patients lack classic features, they may be misdiagnosed as having chronic bronchitis,
leading to diagnostic controversies. It is necessary to reconsider and redefine chronic bronchitis,
taking into account the potential for diagnostic overlap with asthma and the disconnect between
its historical background and current clinical understanding.
COPD is currently considered an “umbrella term” that encompasses “diverse phenotypes” due
to the combination of emphysema and chronic bronchitis, two structurally and clinically
distinct diseases, into a heterogeneous disease entity [55]. From a historical perspective, this
heterogeneity may be, to some extent, an artificial construct. However, the terminology of
chronic bronchitis is increasingly used in contemporary clinical phenotyping efforts, extending
beyond its origin as a historical artifact. It should be recognized that a productive cough remains
a relevant clinical feature in a subset of patients with COPD and has been associated with
outcomes such as exacerbation risk. Further studies are needed to establish a clinically
meaningful and historically informed definition of chronic bronchitis.
Emphysema, currently defined solely as “destruction of alveolar septa distal to terminal
bronchioles”, neglects inflammatory changes [56]. Expanding asthma criteria to include
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diverse clinical manifestations would resolve confusion regarding corticosteroid
responsiveness and eosinophilia, which are better explained by asthma. Steroid responsiveness
and blood eosinophilia could even serve as adjunctive diagnostic criteria for asthma. Based on
these concepts, the diagnostic boundaries of emphysema and asthma may be broadened to
include certain features of chronic bronchitis. However, current studies suggest that steroid-
responsive COPD cannot be fully attributed to undiagnosed asthma alone, without considering
the possibility of a distinct eosinophilic COPD phenotype.
The evolving landscape of GOLD patient stratification
Throughout the GOLD era, significant changes have occurred in patient stratification. Initially,
disease severity was classified into four stages based on FEV1 in 2007 [57]. In 2011, symptom
severity and exacerbation history were incorporated to create a two-dimensional “combined
initial assessment” (ABCD grades), as FEV1 alone did not adequately reflect symptom severity,
health status, functional limitation, quality of life, or outcome [58, 59]. Exacerbation history
also emerged as a strong predictor of future exacerbation risk [60]. By 2017, FEV1 was
removed from the scheme, and the assessment tool was solely on symptom scores and
exacerbation risks [9]. In 2023, the four-sector design was simplified to a three-sector ABE
grade system [10].
These revisions raise several concerns. First, FEV1 remains an important objective measure
for treatment guidance. Numerous studies have demonstrated the significance of FEV1 for
outcome prediction [61, 62]. The new combined assessment system has failed to outperform
the older staging system in terms of mortality prediction [63, 64]. Furthermore, strong
correlations exist between FEV1 changes and patient-reported health status [65-67]. The
GOLD report’s assertion that “FEV1 may be useful for population levels, but not individual
evaluation” is contradicted by the individual-level studies that have found superior
performance of lung function tests over the ABCD assessment [7, 63, 64, 68]. Statistical
analysis of grouped populations aims to elucidate the significance for individual application,
not solely for population characterization.
Second, the combined assessment grouping may be limited in terms of clinical distinction, as
early dual bronchodilator (LABA/LAMA) therapy is widely recommended, despite the GOLD
report’s advocacy for the use of single bronchodilators in group A. Treatment options have
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increasingly converged across groups, favouring dual bronchodilators and discouraging ICS
use.
Third, the division of a wide scoring range into only two sectors is arbitrary. The COPD
assessment test (CAT), with scores ranging from 0 to 40, assigns patients with scores of 9 and
10 to different groups, despite similar symptom severity. Fourth, the horizontal axis, based on
CAT or modified MRC (mMRC) scores, yields significantly different patient groupings near
the border [69]. Finally, the vertical axis, based on exacerbation frequency, lacks universally
defined acute exacerbation and frequent exacerbator criteria [12, 70, 71]. Exacerbation
frequency varies yearly in individuals [72, 73]. Dividing exacerbation risk into two sectors
oversimplifies the significance of each incremental exacerbation [74].
Finding better lung function test criteria for COPD
The 2025 GOLD report addresses several key issues related to spirometry interpretation [75].
BDR testing is no longer routinely recommended, reflecting its limited clinical utility. Airflow
obstruction is often defined as an FEV1/forced vital capacity (FVC) ratio of < 0.7, particularly
in COPD diagnosis. However, this fixed ratio should not be considered an absolute criterion,
as it naturally decreases with age and can be influenced by various conditions and diseases [76-
79]. Minor restrictive conditions, such as interstitial lung abnormalities, senile pulmonary
fibrosis, pleural thickening, obesity, muscular weakness, and insufficient effort during testing,
can also affect the ratio by decreasing FVC [77, 80].
The normal FEV1 range, traditionally 80–120% of predicted values based on the coefficient of
variation (CV), applies primarily to young, healthy adults in their 20s. Younger and older
individuals exhibit wider ranges [76, 81]. Furthermore, predicted normal spirometric values
vary significantly depending on race and the reference standards applied [81]. Preserved ratio
impaired spirometry (PRISm), a recently discussed phenomenon, may be a product of
variability rather than a distinct entity, given the aforementioned lung-function-test limitations
[82]. The American Thoracic Society (ATS)/European Respiratory Society (ERS) technical
standards advise against using a fixed FEV1/FVC ratio < 0.7 for airflow obstruction and an
FEV1 > 80% of predicted value for normality [79]. However, GOLD continues to advocate for
the fixed ratio. While the 80% predicted normality limit is not explicitly mentioned in the
GOLD report, it remains common in clinical practice and research. The ATS/ERS technical
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standards recommend z-scores as a statistically robust methodology [83]. However, the GOLD
report has not fully endorsed the use of z-score, citing a lack of sufficient supporting evidence
[75].
Establishing normal criteria for human performance measurements, including lung function, is
challenging. More important than reference selection is the understanding that results should
be interpreted cautiously, acknowledging the potential for misjudgement, regardless of the
chosen reference and criteria. However, spirometry results are often applied too rigidly in
COPD diagnosis and assessment, despite existing controversies.
Conclusion
The GOLD strategy played a pivotal role in shaping COPD management worldwide through
sustained global collaboration. Proper COPD understanding and management are long-term
endeavours that require reasonable and prudent approaches for future generations. For this
significant disease, objective evaluation and critical analysis of controversial issues are
essential.
Collaborative efforts that promote open discussion and constructive criticism are essential for
advancing the understanding of COPD. Clear and distinct definitions of asthma and COPD,
particularly chronic bronchitis, are critical prerequisites for refining treatment principles and
strategies. In addition, clinical diagnostic criteria and lung function testing require thorough re-
evaluation to improve the accuracy of COPD assessment and optimize patient management.
Provenance: Submitted article, peer reviewed.
Conflict of interest: The author has nothing to disclose.
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