Is oxidative stress associated with disease severity, pulmonary function and metabolic syndrome in chronic obstructive pulmonary disease? / ¿Está el estrés oxidativo asociado a la gravedad de la enfermedad, a la función pulmonar y al síndrome metabólico en la enfermedad pulmonar obstructiva crónica?

OBJECTIVE: To investigate associations between oxidant/antioxidant biomarkers with the disease severity, pulmonary function and diagnosis of metabolic syndrome (MetS) in patients with COPD. METHODS: Seventy-four subjects were included, 39 with COPD (age 69±7 years; female 41%) and 35 for control group (age 69±7 years; female 43%). They were diagnosed with MetS and allocated in one of 4 subgroups: COPD and control, with and without MetS, respectively. Advanced oxidation protein products (AOPP), paraoxonase-1, catalase activity, sulfhydryl group and total lipid hydroperoxide were assayed. Pulmonary function was performed with a plethysmograph. RESULTS: COPD severity (GOLD≥3) and pulmonary function were associated with sulfhydryl group and AOPP (P≤.03 for all). The prevalence of MetS was associated with AOPP in COPD (P=.04). Individuals with COPD and MetS showed higher AOPP compared to COPD without MetS (P<.0001). CONCLUSION: COPD severity, worse pulmonary function and presence of metabolic syndrome are associated with oxidative stress in individuals with COPD.