Chronic obstructive pulmonary disease (COPD) is a progressive respiratory disorder associated with substantial morbidity and healthcare costs. Effective outpatient management can prevent exacerbations and reduce hospitalizations [1,2]. In South Korea, the government conducts an annual quality assessment of medical benefits to enhance healthcare quality across 36 areas, including primary care, chronic disease management, acute care, mental health, and long-term care [3]. In chronic disease management, COPD quality assessments focus on sustained patient follow-ups, medication adherence, and laboratory testing to ensure effective disease control. Since 2014, COPD quality assessments have been conducted to improve disease management, prevent disease progression, and ensure appropriate healthcare. The results of the 9th COPD quality assessment conducted between January and December 2023 have recently been published. This evaluation targeted outpatients with COPD across various healthcare settings, including tertiary hospitals, general hospitals, mid-sized hospitals, clinics, long-term care hospitals, psychiatric hospitals, and public health institutions. The evaluation criteria included pulmonary function test (PFT) rates, rate of continuous outpatient visits, and inhaled bronchodilator prescription rates, which are critical indicators of the quality of COPD management. PFTs are essential for the diagnosis of COPD, assessment of disease severity, and objective evaluation of treatment efficacy. The rate of continuous outpatient visits is evaluated by monitoring whether patients with COPD receive regular medical consultations, which is crucial for long-term disease management. The inhaled bronchodilator prescription rate serves as an indicator of treatment appropriateness, because these medications are the cornerstone of COPD management [4]. The aim of our study was to evaluate the outcomes and trends of the COPD quality assessment program in Korea from 2014 to 2023, focusing on changes in disease management achieved through this program and highlighting ongoing challenges in outpatient care.

The COPD quality assessment, conducted by the Health Insurance Review and Assessment Service, included healthcare institutions that billed outpatient services for COPD (International Classification of Diseases 10th Revision [ICD-10] codes J43, J44 excluding J43.0) under the national health insurance, medical aid, or veterans’ benefits programs. Eligible patients were those aged ≥40 years with at least two outpatient visits with COPD medication prescription or one hospitalization requiring systemic corticosteroid administration, and an outpatient visit with COPD medication prescription. Patients who died during the assessment period were excluded from all denominators. The quality assessment evaluated the appropriateness and continuity of COPD care using five performance indicators.

The rate of PFT implementation was defined as the proportion of eligible patients who underwent at least one PFT during the assessment period. The numerator included patients who received either of the following procedure codes: F6001 (basic PFT without flow-volume curve) or F6002 (flow-volume curve including basic PFT).

PFT rate (%)=(number of COPD patients who received a PFT at least once/total number of eligible COPD patients)×100

The rate of continuous outpatient visits assessed care continuity by calculating the proportion of patients who had at least three COPD-related outpatient visits at the same healthcare institution during the evaluation period. Each visit was defined as a claim with a COPD diagnosis (ICD-10 J43-J44, excluding J43.0) as the primary or first secondary diagnosis and a prescription for COPD-related medication. The denominator included patients who consistently received care from a single institution throughout the evaluation period and also visited the same institution at the end of the previous year. Those who received COPD care from multiple institutions were excluded.

Continuous visit rate (%)=(number of patients with ≥3 COPD visits to the same institution/total number of eligible patients for continuity assessment)×100

The rate of inhaled bronchodilator prescriptions reflected the proportion of COPD patients prescribed at least one inhaled bronchodilator during the assessment period. Included medications were long-acting beta2 agonists (LABA), short-acting beta2 agonists, and long-acting muscarinic antagonists (LAMA).

Inhaled bronchodilator prescription rate (%)=(number of patients prescribed inhaled bronchodilators at least once/total number of eligible COPD patients)×100

For the monitoring index, the rate of COPD-related hospitalizations was defined as the proportion of patients who were hospitalized at least once due to COPD. COPD-related hospitalization was identified by the presence of a COPD diagnosis (ICD-10 J43-J44, excluding J43.0) as the primary or first secondary diagnosis and the prescription of a COPD-related medication during the hospital stay. Hospital admissions at both index and external institutions were included in this analysis.

COPD-related hospitalization rate (%)=(number of patients with ≥1 COPD-related hospitalization/total number of eligible COPD patients)×100

The rate of COPD-related emergency room (ER) visits served measured the proportion of patients who visited the ER at least once due to COPD. A qualifying ER visit required a COPD diagnosis (J43-J44, excluding J43.0) as the primary or first secondary diagnosis, a prescription for COPD-related medication, and an associated emergency medical care fee code. ER visits at both index and external institutions were included.

COPD-related ER visit rate (%)=(number of patients with ≥1 COPD-related ER visit/total number of eligible COPD patients)×100

Finally, the composite performance score was calculated on a 100-point scale by summing the weighted scores of the key performance indicators. Each indicator score was multiplied by assigned weight—PFT rate (0.4), rate of continuous outpatient visits (0.2), and rate of inhaled bronchodilator prescriptions (0.4)—and the weighted scores were then summed to yield the final composite score. COPD quality assessment results were classified into five grades based on their performance scores: grade 1 (≥80 points), grade 2 (65-79.9 points), grade 3 (50-64.9 points), grade 4 (35-49.9 points), and grade 5 (<35 points), with a lower grade indicating a higher quality of care at the institution. These results have been publicly disclosed to promote transparency and encourage quality improvement [4].

The 2023 assessment evaluated data from 6,339 institutions and 158,906 patients. The PFT rate increased from 58.7% in 2014 to 80.3% in 2023, with the highest rates observed in tertiary hospitals (92.0%) and the lowest in clinics (53.6%). The inhaled bronchodilator prescription rate reached 91.5%, reflecting a continuous improvement in pharmacological therapy. However, the continuity of outpatient care declined to 80.2%, while COPD-related hospitalization (10.8%) and ER visit rates (6.4%) increased, highlighting persistent gaps in outpatient management. Although quality assessment programs have significantly improved diagnostic and pharmacological care, regional disparities and declining the rate of continuous outpatient visits suggest a need for enhanced primary care support, patient education, and self-management strategies.

The COPD adequacy assessment results serve as fundamental data for government policy development and are shared with relevant academic societies to encourage voluntary improvements in healthcare quality. Certification as a high-performing institution is awarded to grade 1 clinics. This evaluation is designed to promote self-directed quality enhancement by linking financial support to performance outcomes. The evaluation results were disseminated to relevant departments at the headquarters and regional offices for administrative use and integration into the policy and review domains. To support quality improvement initiatives, targeted quality improvement programs have been implemented for institutions ranked in the lower tiers of assessment. Furthermore, the Korean Academy of Tuberculosis and Respiratory Diseases plays a role in promoting education for primary care physicians and conducting public awareness campaigns on COPD including events such as ‘lung day.’ Promotional materials, such as posters and leaflets on chronic respiratory diseases, have been continuously distributed by academic society to enhance disease awareness and proactive management.

The observed decline in COPD-related hospitalization rates in Korea over the past decade may reflect the impact of this national quality assessment initiative. When compared with OECD data, Korea demonstrated a steeper and more sustained reduction in hospitalization rates, particularly between 2016 and 2021. The divergence between Korea and the OECD average became more pronounced following the sixth assessment cycle. This trend suggests that Korea’s policy-driven approach, which emphasizes regular performance evaluation, public disclosure, and financial incentives for high-performing institutions, may have played a meaningful role in improving outpatient management and reducing the burden on acute care services. Although cross-country comparisons should be interpreted with caution due to differences in healthcare systems and data definitions, this finding provides valuable international context that supports the interpretation of the program’s effectiveness

Hospitalization and ER visit rates for COPD decreased from 2020 to 2021 but subsequently rebounded in 2023. Ahn and Park [8] conducted a systematic review and meta-analysis of 23 studies, revealing a significant increase in in-hospital mortality and a concurrent decline in hospitalization rates during the COVID-19 pandemic. These findings highlight the challenges posed by reduced hospital accessibility and delays in timely patient screening and classification. The recent resurgence in COPD-related hospitalizations and ER visits in 2023 may, in part, reflect the easing of public health measures following the COVID-19 pandemic. The relaxation of social distancing, mask mandates, and other non-pharmaceutical interventions in 2022-2023 likely contributed to re-emergence of common respiratory infections, such as upper respiratory tract infections, influenza, and pneumonia, which are known triggers for acute exacerbations of COPD [9]. Increased community transmission of these pathogens could have heightened the vulnerability of COPD patients, particularly older adults with comorbidities, leading to increased acute-care utilization. However, other explanations should also be considered. These include the accumulated burden of delayed care during the pandemic years, under-treatment in primary care, or coding shifts associated with healthcare system normalization. Our data align with the results of this meta-analysis, emphasizing the need for improved healthcare strategies and pandemic preparedness to manage chronic respiratory conditions during future public health crises. In addition, the plateau of ER visit rates requires continuous monitoring to assess future trends.

Several factors should be considered when interpreting these findings. First, COPD was operationally defined on the basis of administrative claims and pharmacotherapy records, without confirming persistent airflow limitation by post-bronchodilator spirometry. This surrogate definition may have misclassified asthma or other chronic airway diseases as COPD, thereby introducing diagnostic heterogeneity. Second, individual pulmonary function parameters (e.g., forced expiratory voulme in 1 second, forced vital capacity, Global Initiative for Chronic Obstructive Lung Disease [GOLD] stage) were not captured in the claims database, precluding stratification by disease severity and assessment of treatment appropriateness relative to lung function impairment. Third, patients who died during the assessment period were excluded from all denominators, which could have removed the sickest individuals and thereby underestimated the true burden of suboptimal care. Finally, reliance on reimbursement data renders the analysis susceptible to miscoding, incomplete records, and residual confounding by unmeasured variables such as smoking status, socioeconomic factors, or comorbid conditions. Future studies that integrate claims with spirometry registries and clinical datasets are warranted to validate disease definitions, enable severity-specific analyses, and mitigate these sources of bias.

To increase PFT implementation in primary care settings, spirometry should be included in screening programs for high-risk groups. Strengthening early detection and disease monitoring through increased PFT implementation, enhancing treatment adherence and rate of continuous outpatient visits, and reducing hospital admissions by optimizing outpatient management strategies are essential for improving COPD outcomes. Additionally, incorporating COPD into primary care chronic disease management pilot programs and ensuring appropriate reimbursement for inhaler education are crucial for improving patient outcomes.

The decade-long COPD quality assessment from 2014 to 2023 indicated significant progress in COPD management, particularly in diagnostic testing and pharmacological therapy, but also emphasized the need for improved rate of continuous outpatient visits in outpatient strategies. The rise in COPD-related hospitalizations and ER visits underscores the persistent gaps in outpatient care. Several factors may have contributed to these trends, including issues with treatment adherence, inadequate patient education on disease management, and the impact of the COVID-19 pandemic. Regional variations further emphasize the need for targeted interventions to support lower-performing areas. Enhancing public awareness and implementing healthcare provider initiatives are crucial for optimizing COPD outcomes. Policymakers should focus on strengthening primary care support and integrating personalized self-management programs to address these challenges.