J Korean Med Sci.  2024 Mar;39(10):e96. 10.3346/jkms.2024.39.e96.

Nationwide Study of the Epidemiology, Diagnosis, and Treatment of Hypersensitivity Pneumonitis in Korea

• Jung HI
• Nam DR
• You SH
• Jung JW
• Gu KM
• Jung SY

• KMID: 2554199
• DOI: http://doi.org/10.3346/jkms.2024.39.e96

Abstract

Background
Hypersensitivity pneumonitis (HP) is a condition with an uncertain global incidence, and information on its diagnosis and management is limited. This study aimed to address these knowledge gaps.
Methods
This study utilized customized claims data from the Health Insurance Review and Assessment Service (HIRA) in South Korea from January 2010, to December 2021. Patients with HP were identified based on the diagnosis code (International Classification of Diseases, 10th Revision, J67) between 2011 and 2020. Incident HP cases were defined as new HP claims, excluding those with claims in the previous year. The study examined various factors such as age, sex, comorbidities, diagnostic methods, and treatment patterns. Additionally, multivariate logistic regression analysis was performed to identify risk factors associated with treatment initiation.
Results
A total of 8,678 HP incident cases were confirmed, with age- and sex-adjusted annual incidence rates ranging from 1.14/100,000 in 2020 to 2.16/100,000 in 2012. The mean age of patients with incident HP was 52 years, with a higher incidence observed among males. Additionally, the most common comorbidity was asthma. Bronchoscopy was performed on 16.9% of patients, and 25.4% of patients did not receive treatment within 1 year of diagnosis. Among those who received treatment, prednisone was the most used systemic steroid, and azathioprine was the most commonly used second-line immunosuppressant. Factors associated with treatment initiation included the female sex, having asthma or gastroesophageal reflux disease (GERD), and undergoing bronchoscopy.
Conclusion
This study provides valuable insights into the incidence, diagnosis, and treatment patterns of HP in South Korea using nationwide medical claims data.

Keyword

Incidence; Diagnosis; Bronchoscopy; Treatment; Hypersensitivity Pneumonitis

Figure

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  Fig. 1 Identification of cases of hypersensitivity pneumonitis from the Health Insurance Review and Assessment Service database.HP = hypersensitivity pneumonitis.

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  Fig. 2 Annual trend of the incidence of hypersensitivity pneumonitis in Korea, 2011–2020.

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  Fig. 3 Multivariate logistic regression analysis of factors associated with the treatment initiation of patients with hypersensitivity pneumonitis.COPD = chronic obstructive pulmonary disease, GERD = gastroesophageal reflux disease, aOR = adjusted odds ratio, CI = confidence interval.

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