Changhwan Kim1,2, Yousang Ko2,3, Su Hee Kim4, Hyun Ju Yoo4, Jae Seung Lee2,5, Chin Kook Rhee2,6, Jin Hwa Lee2,7, Ji-Hyun Lee2,8, Tae-Hyung Kim2,9, Seong Yong Lim2,10, Kwang Ha Yoo2,11, Joon Beom Seo12, Yeon-Mok Oh2,5, Sang-Do Lee2,5, Yong Bum Park2,3. 1. Department of Internal Medicine, Jeju National University Hospital, Jeju National University School of Medicine, Jeju, Republic of Korea. 2. Clinical Research Center for Chronic Obstructive Airway Diseases, Seoul, Republic of Korea. 3. Department of Pulmonary and Critical Care Medicine, Hallym University Kangdong Sacred Heart Hospital, Seoul, Republic of Korea. 4. Department of Convergence Medicine, Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea. 5. Department of Pulmonary and Critical Care Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea. 6. Department of Internal Medicine, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea. 7. Department of Internal Medicine, Ewha Womans University Mokdong Hospital, College of Medicine, Ewha Womans University, Seoul, Republic of Korea. 8. Department of Internal Medicine, CHA Bundang Medical Center, CHA University, Seongnam, Republic of Korea. 9. Division of Pulmonology, Department of Internal Medicine, Hanyang University Guri Hospital, Hanyang University College of Medicine, Guri, Republic of Korea. 10. Division of Pulmonary and Critical Care Medicine, Department of Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea. 11. Department of Internal Medicine, Konkuk University School of Medicine, Seoul, Republic of Korea. 12. Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
Abstract
BACKGROUND AND OBJECTIVE: Matrix degradation is a key feature of chronic obstructive pulmonary disease (COPD). Desmosine and isodesmosine (desmosines) are excreted in urine following matrix degradation. The main purpose of this study was to investigate the association between computed tomography (CT) emphysema indices and urinary desmosines in patients with COPD. METHODS: A total of 152 subjects were selected from the Korean Obstructive Lung Disease cohort. Their urine samples were assayed for desmosines using liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods. The cohort was divided into emphysema-dominant (n = 80) and non-emphysema dominant- (n = 72) groups according to the CT emphysema index. RESULTS: The level of urinary desmosines was significantly higher in the emphysema-dominant group. Significant differences were also observed between the two groups for body mass index and lung function. Multivariate analysis indicated that a high level of urinary desmosines was a significant independent predictor of emphysema (relative risk: 2.6; 95% CI: 1.11-6.09; P = 0.028). The percentage of frequent exacerbators was significantly higher in the high urinary desmosine group in the first year of follow-up (P = 0.041). The mean number of exacerbations was higher in the high urinary desmosine group, although this difference was not statistically significant (P = 0.067). The changes in emphysema index did not differ between the two urinary desmosine groups over 3 years of follow-up. CONCLUSION: This study indicates that the level of urinary desmosines measured by LC-MS/MS methods is associated with the CT emphysema index. Urinary desmosine can be a useful predictor in identifying frequent exacerbators.
BACKGROUND AND OBJECTIVE: Matrix degradation is a key feature of chronic obstructive pulmonary disease (COPD). Desmosine and isodesmosine (desmosines) are excreted in urine following matrix degradation. The main purpose of this study was to investigate the association between computed tomography (CT) emphysema indices and urinary desmosines in patients with COPD. METHODS: A total of 152 subjects were selected from the Korean Obstructive Lung Disease cohort. Their urine samples were assayed for desmosines using liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods. The cohort was divided into emphysema-dominant (n = 80) and non-emphysema dominant- (n = 72) groups according to the CT emphysema index. RESULTS: The level of urinary desmosines was significantly higher in the emphysema-dominant group. Significant differences were also observed between the two groups for body mass index and lung function. Multivariate analysis indicated that a high level of urinary desmosines was a significant independent predictor of emphysema (relative risk: 2.6; 95% CI: 1.11-6.09; P = 0.028). The percentage of frequent exacerbators was significantly higher in the high urinary desmosine group in the first year of follow-up (P = 0.041). The mean number of exacerbations was higher in the high urinary desmosine group, although this difference was not statistically significant (P = 0.067). The changes in emphysema index did not differ between the two urinary desmosine groups over 3 years of follow-up. CONCLUSION: This study indicates that the level of urinary desmosines measured by LC-MS/MS methods is associated with the CT emphysema index. Urinary desmosine can be a useful predictor in identifying frequent exacerbators.