Seri Hong1, Eun-Cheol Park2,3, Tae Hyun Kim3,4, Jeoung A Kwon1, Ki-Bong Yoo5, Kyu-Tae Han2,3, Ji Won Yoo6, Sun Jung Kim7. 1. National Cancer Control Institute, National Cancer Center, Goyang, Korea. 2. Department of Preventive Medicine, Yonsei University College of Medicine, Seoul, Korea. 3. Institute of Health Services Research, Yonsei University College of Medicine, Seoul, Korea. 4. Department of Hospital Administration, Graduate School of Public Health, Yonsei University, Seoul, Korea. 5. Department of Healthcare Management, Eulji University, Seongnam, Korea. 6. Department of Internal Medicine, University of Nevada School of Medicine, Las Vegas, Nevada, USA. 7. Department of Health Administration and Management, College of Medical Science, Soonchunhyang University, Asan, Korea.
Abstract
BACKGROUND: Common diseases with potential to increase the risk of death from lung cancer have so far not been studied in large populations. METHODS: We did a population-based retrospective cohort study using nationwide health insurance claims data from 2005 to 2012 in Korea including 205 403 lung cancer patients. Multivariate-adjusted hazard ratios (aHRs) of lung cancer mortality by presence, time intervals with lung cancer diagnosis and combinations of pre-existing chronic obstructive pulmonary disease (COPD), pneumonia, asthma and tuberculosis were calculated using the Cox-proportional hazards model. RESULTS: The total number of person-years of follow-up was 397 780 and 60.2% of patients died (mean survival 23.2 months after lung cancer diagnosis). Lung cancer patients with previous respiratory disease had increased aHR for mortality (COPD, hazard ratio [HR] = 1.32, CI 1.29-1.35; pneumonia, HR = 1.14, CI 1.08-1.19; and asthma, HR = 1.11, CI 1.06-1.16). Risks were positively associated with longer duration of pre-existing disease diagnosis; cases with >5 years since diagnosis compared to <2 years: COPD, HR = 2.91, CI 2.82-3.00; pneumonia, HR = 1.67, CI 1.51-1.85; asthma, HR = 1.56, CI 1.45-1.68; and tuberculosis, HR = 2.03, CI 1.90-2.17. Furthermore, elevated HRs of death were found among patients with multiple pre-existing co-morbidities. CONCLUSION: Hazards of death from lung cancer are significantly increased in cases with pre-existing lung disease, and worse with longer durations, and with multiple combinations before cancer diagnosis. Patients and physicians should be aware of these meaningful risk/prognostic factors for lung cancer when identifying high-risk patient groups.
BACKGROUND: Common diseases with potential to increase the risk of death from lung cancer have so far not been studied in large populations. METHODS: We did a population-based retrospective cohort study using nationwide health insurance claims data from 2005 to 2012 in Korea including 205 403 lung cancerpatients. Multivariate-adjusted hazard ratios (aHRs) of lung cancer mortality by presence, time intervals with lung cancer diagnosis and combinations of pre-existing chronic obstructive pulmonary disease (COPD), pneumonia, asthma and tuberculosis were calculated using the Cox-proportional hazards model. RESULTS: The total number of person-years of follow-up was 397 780 and 60.2% of patients died (mean survival 23.2 months after lung cancer diagnosis). Lung cancerpatients with previous respiratory disease had increased aHR for mortality (COPD, hazard ratio [HR] = 1.32, CI 1.29-1.35; pneumonia, HR = 1.14, CI 1.08-1.19; and asthma, HR = 1.11, CI 1.06-1.16). Risks were positively associated with longer duration of pre-existing disease diagnosis; cases with >5 years since diagnosis compared to <2 years: COPD, HR = 2.91, CI 2.82-3.00; pneumonia, HR = 1.67, CI 1.51-1.85; asthma, HR = 1.56, CI 1.45-1.68; and tuberculosis, HR = 2.03, CI 1.90-2.17. Furthermore, elevated HRs of death were found among patients with multiple pre-existing co-morbidities. CONCLUSION: Hazards of death from lung cancer are significantly increased in cases with pre-existing lung disease, and worse with longer durations, and with multiple combinations before cancer diagnosis. Patients and physicians should be aware of these meaningful risk/prognostic factors for lung cancer when identifying high-risk patient groups.