Imbalance of Endogenous Hydrogen Sulfide and Homocysteine in Chronic Obstructive Pulmonary Disease Combined with Cardiovascular Disease.

Considerable studies showed associations between chronic obstructive pulmonary disease (COPD) and cardiovascular disease (CVD), we evaluated the role of endogenous hydrogen sulfide (HS)/homocysteine (Hcy) in patients with COPD combined with CVD. Fifty one stable patients with COPD were enrolled (25 COPD, 26 COPD + CVD). Lung function, sputum, peripheral blood samples, serum HS, Hcy, high-sensitivity C-reactive protein (hs-CRP) and tumor necrosis factor-α (TNF-α) levels were measured. Dyspnea, symptoms and quality of life were quantified by modified Medical Research Council dyspnea scale (mMRC), COPD assessment test (CAT) and St. George's Respiratory Questionnaire (SGRQ). Compared with COPD group, waist circumference and body mass index (BMI) were higher in COPD + CVD group, mMRC, CAT and activity scores were also higher, high density lipoprotein cholesterol (HDL-C) was lower, total cells, neutrophils (%) in sputum and serum hs-CRP level were higher, whereas macrophages (% ) in sputum was lower. HS and Hcy levels from COPD + CVD group were higher than those from COPD group, but HS/Hcy ratio was lower. With increasing COPD severity, HS level was decreased, however, Hcy level was increased. HS level was positively correlated with FEV/FVC, FEV% predicted, lymphocytes (%) and macrophages (%) in sputum, but negatively correlated with smoking pack-years and neutrophils (%) in sputum. Hcy level was positively correlated with BMI and total cells in sputum. The ratio of HS/Hcy was also positively correlated with FEV/FVC, but negatively correlated with total cells in sputum. The imbalance of HS/Hcy may be involved in the pathogenesis of COPD combined with CVD and provide novel targets for therapy.