biostudies-literatureUnknown148(1)Apperley SCanadian Institutes of Health Research<h4>Background</h4>COPD is a chronic inflammatory disorder associated with oxidative stress. Serum bilirubin has potent antioxidant actions, and higher concentrations have been shown to protect against oxidative stress. The relation between serum bilirubin and COPD progression is unknown.<h4>Methods</h4>Serum bilirubin was measured in 4,680 smokers aged 35 to 60 years old with mild to moderate airflow limitation. The relationship of serum bilirubin to postbronchodilator FEV₁ and rate of FEV1 decline over 3 to 9 years was determined using regression modeling. Total and disease-specific mortality were also ascertained.<h4>Results</h4>Serum bilirubin was positively related to FEV₁ (P < .001). Serum bilirubin was also negatively related to the annual decline in FEV₁ when adjusted for baseline Chest169-175https://www.ebi.ac.uk/biostudies/studies/S-EPMC4493872biostudies-literatureSerum Bilirubin and Disease Progression in Mild COPD.PMC4493872Tashkin DMan SFPSin DDWise RAConnett JEPark HYApperley SHolmes DTfalseSerum Bilirubin and Disease Progression in Mild COPD.<h4>Background</h4>COPD is a chronic inflammatory disorder associated with oxidative stress. Serum bilirubin has potent antioxidant actions, and higher concentrations have been shown to protect against oxidative stress. The relation between serum bilirubin and COPD progression is unknown.<h4>Methods</h4>Serum bilirubin was measured in 4,680 smokers aged 35 to 60 years old with mild to moderate airflow limitation. The relationship of serum bilirubin to postbronchodilator FEV₁ and rate of FEV1 decline over 3 to 9 years was determined using regression modeling. Total and disease-specific mortality were also ascertained.<h4>Results</h4>Serum bilirubin was positively related to FEV₁ (P < .001). Serum bilirubin was also negatively related to the annual decline in FEV₁ when adjusted for baseline 2015-01-01T00:00:00Z2015 Jul2025-05-18T12:28:35.985Z2025-05-18T12:28:35.985ZS-EPMC44938722553928510.1378/chest.14-2150