COPD Risk Factor Profiles in General Population and Referred Patients: Potential Etiotypes

Abstract

Purpose

To identify the risk factors for chronic obstructive pulmonary disease (COPD) in view of potential etiotypes in a general population and referred COPD patients.

Patients and Methods

We performed a cross-sectional observational study utilizing two distinct datasets: a dataset of a general population including 2430 subjects with COPD from the Korea National Health and Nutrition Examination Survey (KNHANES) and another dataset of referral clinics including 579 patients with COPD from the Korean Obstructive Lung Disease (KOLD).

Results

The mean age of both groups was 67 years, and 71.2% and 93.8% were male in the COPD subjects from the KNHANES and the KOLD, respectively. The mean forced expiratory volume in 1 second of predicted value was 79.1% (KNHANES) and 55.4% (KOLD). The frequency of risk factors of cigarette smoking (C), infection (I), pollution (P), and asthma (A) was 54.6%, 9.4%, 10.7%, and 7.9%, respectively, in the KNHANES COPD subjects, and 88.4%, 26.6%, 41.6%, and 35.2%, respectively, in the KOLD COPD subjects. Risk factors were unidentified in 32.6% (KNHANES) and 3.1% (KOLD) of COPD subjects. Additionally, 14.1% and 66.2% of subjects with COPD had two or more risk factors in the KNHANES and KOLD, respectively.

Conclusion

The profiles of risk factors C, I, P, and A were identified and appeared to be different among the two COPD groups from a general population or referral clinics. In some of the COPD subjects, risk factors were not identified, so we should endeavour to find out unidentified COPD risk factors, especially in the general population.

Keywords:

• chronic obstructive pulmonary disease
• etiotype
• smoking
• tuberculosis
• asthma
• pollutants

Abbreviations

C, cigarette smoking; I, infection; A, asthma; P, biomass or/and pollution exposure; aOR, adjusted odds ratio; BMI, body mass index; CI, confidence interval; COPD, chronic obstructive pulmonary disease; FEV₁, forced expiratory volume in 1 sec; FVC, forced vital capacity; GOLD, Global Initiative for Chronic Obstructive Lung Disease; KNHANES, the Korea National Health and Nutrition Examination Survey; KOLD, the Korean Obstructive Lung Disease cohort.

Data Sharing Statement

The datasets used or analyzed during the current study are available from the corresponding author upon reasonable request.

Acknowledgments

The study protocol was approved by the Institutional Review Board of the Asan Medical Centre (IRB no.: 2022-1717). The board waived the requirement for obtaining patient informed consent because of the nature of the analysis. The KNHANES and KOLD datasets are, respectively, managed and supervised by the Korea Centers for Disease Control and Prevention and Obstructive Lung Disease Research Foundation for data protection and privacy regulation. All provided information is anonymized in the KNHANES and KOLD datasets. The data accessed complied with relevant data protection and privacy regulations.

Disclosure

The authors report no conflicts of interest in this work.

Additional information

Funding

There is no funding to report.