{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T22:35:00Z","timestamp":1792103700914,"version":"4.4.0"},"reference-count":57,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,7,16]],"date-time":"2026-07-16T00:00:00Z","timestamp":1784160000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medicina"],"abstract":"<jats:p>Background and Objectives: Oxidative stress is widely recognized as a key contributor to both the development and progression of chronic obstructive pulmonary disease (COPD), particularly during acute exacerbations (AECOPD). 8-Hydroxy-2\u2032-deoxyguanosine (8-OHdG), a marker of oxidative DNA damage, has been insufficiently investigated as a systemic biomarker in this setting. This study evaluated the relationship between serum 8-OHdG levels, airflow limitation severity, and smoking status in patients hospitalized with AECOPD. Materials and Methods: We conducted a cross-sectional study including 176 patients admitted for AECOPD and stratified according to Global Initiative for Chronic Obstructive Lung Disease (GOLD) stages. The study population comprised patients with comparable distributions of age, sex, smoking status, diabetes, cardiovascular comorbidities, and area of residence across GOLD categories. Serum 8-OHdG, leukocyte count, neutrophil percentage, C-reactive protein (CRP), fibrinogen, and procalcitonin were measured. Group comparisons, multivariable logistic regression analyses, and smoking-status subgroup analyses were performed. Results: Serum 8-OHdG levels increased significantly with advancing airflow limitation severity (p = 0.038), with higher concentrations observed in patients with GOLD 4 disease compared to GOLD 1\u20132 disease (p = 0.023). In multivariable analysis, 8-OHdG was the only biomarker independently associated with GOLD stage (OR = 2.44, 95% CI: 1.12\u20135.31, p = 0.025). Higher serum 8-OHdG levels were also independently associated with smoking status (OR = 1.20, 95% CI: 1.05\u20131.37, p = 0.022). Ever-smokers demonstrated significantly higher 8-OHdG concentrations than never-smokers in GOLD 1\u20132 and GOLD 3 disease, whereas procalcitonin levels were higher among never-smokers with advanced COPD. Conclusions: Serum 8-OHdG levels measured during AECOPD are associated with both airflow limitation severity and smoking status. These findings support the potential role of oxidative DNA damage as a clinically relevant component of COPD pathophysiology and suggest that serum 8-OHdG may represent a useful biomarker for disease characterization in patients experiencing acute exacerbations.<\/jats:p>","DOI":"10.3390\/medicina62071369","type":"journal-article","created":{"date-parts":[[2026,7,16]],"date-time":"2026-07-16T08:08:34Z","timestamp":1784189314000},"page":"1369","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Serum 8-OHdG as a Marker of Oxidative DNA Damage in Acute Exacerbations of COPD: Associations with GOLD Stage and Smoking Status\u2014A Cross Sectional Study"],"prefix":"10.3390","volume":"62","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-1281-9862","authenticated-orcid":false,"given":"Larisa Alexandra","family":"Rus","sequence":"first","affiliation":[{"name":"Department of Internal Medicine, Faculty of Medicine, \u201cVasile Goldi\u0219\u201d Western University of Arad, B-dul Revolu\u021biei nr. 94\u201396, 310025 Arad, Romania"},{"name":"Arad County Emergency Clinical Hospital, Str. Andr\u00e9nyi K\u00e1roly Nr. 2\u20134, 310037 Arad, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-1192-1452","authenticated-orcid":false,"given":"Romana Olivia","family":"Pope\u021biu","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Faculty of Medicine, \u201cVasile Goldi\u0219\u201d Western University of Arad, B-dul Revolu\u021biei nr. 94\u201396, 310025 Arad, Romania"},{"name":"Arad County Emergency Clinical Hospital, Str. Andr\u00e9nyi K\u00e1roly Nr. 2\u20134, 310037 Arad, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2512-2691","authenticated-orcid":false,"given":"Simona Maria","family":"Borta","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Faculty of Medicine, \u201cVasile Goldi\u0219\u201d Western University of Arad, B-dul Revolu\u021biei nr. 94\u201396, 310025 Arad, Romania"},{"name":"Arad County Emergency Clinical Hospital, Str. Andr\u00e9nyi K\u00e1roly Nr. 2\u20134, 310037 Arad, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-6627-2648","authenticated-orcid":false,"given":"Anamaria","family":"V\u00eelcea","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Faculty of Medicine, \u201cVasile Goldi\u0219\u201d Western University of Arad, B-dul Revolu\u021biei nr. 94\u201396, 310025 Arad, Romania"},{"name":"Arad County Emergency Clinical Hospital, Str. Andr\u00e9nyi K\u00e1roly Nr. 2\u20134, 310037 Arad, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9824-3112","authenticated-orcid":false,"given":"Nicolae C\u0103t\u0103lin","family":"Hreniuc","sequence":"additional","affiliation":[{"name":"Arad County Emergency Clinical Hospital, Str. Andr\u00e9nyi K\u00e1roly Nr. 2\u20134, 310037 Arad, Romania"},{"name":"Department of Neurology, Faculty of Medicine, \u201cVasile Goldi\u0219\u201d Western University of Arad, B-dul Revolu\u021biei nr. 94\u201396, 310025 Arad, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-4374-4248","authenticated-orcid":false,"given":"Adrian Silviu","family":"Cri\u0219an","sequence":"additional","affiliation":[{"name":"Arad County Emergency Clinical Hospital, Str. Andr\u00e9nyi K\u00e1roly Nr. 2\u20134, 310037 Arad, Romania"},{"name":"Department of Critical Care and Emergency Medicine, Faculty of Medicine, \u201cVasile Goldi\u0219\u201d Western University of Arad, B-dul Revolu\u021biei nr. 94\u201396, 310025 Arad, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carla Melania","family":"Tama\u0219","sequence":"additional","affiliation":[{"name":"Arad County Emergency Clinical Hospital, Str. Andr\u00e9nyi K\u00e1roly Nr. 2\u20134, 310037 Arad, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paula Alexandra","family":"Vulciu","sequence":"additional","affiliation":[{"name":"Department of Biochemistry, Faculty of Medicine, \u201cVasile Goldi\u0219\u201d Western University of Arad, B-dul Revolu\u021biei nr. 94\u201396, 310025 Arad, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Oana","family":"\u0218tirbu","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Faculty of Medicine, \u201cVasile Goldi\u0219\u201d Western University of Arad, B-dul Revolu\u021biei nr. 94\u201396, 310025 Arad, Romania"},{"name":"Arad County Emergency Clinical Hospital, Str. Andr\u00e9nyi K\u00e1roly Nr. 2\u20134, 310037 Arad, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cecilia","family":"Avram","sequence":"additional","affiliation":[{"name":"Arad County Emergency Clinical Hospital, Str. Andr\u00e9nyi K\u00e1roly Nr. 2\u20134, 310037 Arad, Romania"},{"name":"Department of Biology and Life Science, Faculty of Medicine, \u201cVasile Goldi\u0219\u201d Western University of Arad, B-dul Revolu\u021biei nr. 94\u201396, 310025 Arad, Romania"},{"name":"Clinical Laboratory of Medical Analyses, Arad County Emergency Clinical Hospital, Str. Andr\u00e9nyi K\u00e1roly nr 2\u20134, 310037 Arad, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Denisa","family":"Goldi\u0219","sequence":"additional","affiliation":[{"name":"Arad County Emergency Clinical Hospital, Str. Andr\u00e9nyi K\u00e1roly Nr. 2\u20134, 310037 Arad, Romania"},{"name":"Department of Biology and Life Science, Faculty of Medicine, \u201cVasile Goldi\u0219\u201d Western University of Arad, B-dul Revolu\u021biei nr. 94\u201396, 310025 Arad, Romania"},{"name":"Clinical Laboratory of Medical Analyses, Arad County Emergency Clinical Hospital, Str. Andr\u00e9nyi K\u00e1roly nr 2\u20134, 310037 Arad, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Darius Radu","family":"Roman","sequence":"additional","affiliation":[{"name":"<roman>Doctoral School of Biomedical Sciences, Faculty of Medicine, and Pharmacy, <\/roman>University of Oradea, Str. Universit\u0103\u021bii nr 1, 410087 Oradea, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexandru","family":"Chioreanu","sequence":"additional","affiliation":[{"name":"Department of Otorinolaryngology, Faculty of Medicine, \u201cVasile Goldi\u0219\u201d Western University of Arad, B-dul Revolu\u021biei nr. 94\u201396, 310025 Arad, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Radmila-Anca","family":"Bugari","sequence":"additional","affiliation":[{"name":"Department of Otorinolaryngology, Faculty of Medicine, \u201cVasile Goldi\u0219\u201d Western University of Arad, B-dul Revolu\u021biei nr. 94\u201396, 310025 Arad, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dana","family":"Zdrem\u021ban","sequence":"additional","affiliation":[{"name":"Department of Biochemistry, Faculty of Medicine, \u201cVasile Goldi\u0219\u201d Western University of Arad, B-dul Revolu\u021biei nr. 94\u201396, 310025 Arad, Romania"},{"name":"Department of Otorinolaryngology, Faculty of Medicine, \u201cVasile Goldi\u0219\u201d Western University of Arad, B-dul Revolu\u021biei nr. 94\u201396, 310025 Arad, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cristina Georgiana","family":"Firu","sequence":"additional","affiliation":[{"name":"Department of Heamatology, Faculty of Medicine, \u201cVasile Goldi\u0219\u201d Western University of Arad, B-dul Revolu\u021biei nr. 94\u201396, 310025 Arad, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-9542-0035","authenticated-orcid":false,"given":"Imola","family":"Donath-Miklos","sequence":"additional","affiliation":[{"name":"Department of Biology and Life Science, Faculty of Medicine, \u201cVasile Goldi\u0219\u201d Western University of Arad, B-dul Revolu\u021biei nr. 94\u201396, 310025 Arad, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-0163-5698","authenticated-orcid":false,"given":"Lumini\u021ba","family":"Pilat","sequence":"additional","affiliation":[{"name":"Department of Biochemistry, Faculty of Medicine, \u201cVasile Goldi\u0219\u201d Western University of Arad, B-dul Revolu\u021biei nr. 94\u201396, 310025 Arad, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria","family":"Pu\u0219chi\u021b\u0103","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Faculty of Medicine, \u201cVasile Goldi\u0219\u201d Western University of Arad, B-dul Revolu\u021biei nr. 94\u201396, 310025 Arad, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Barnes, P.J. 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