Diagnostic importance of natriuretic peptide in chronic obstructive pulmonary disease with chronic hypoxemic respiratory failure
Authors:   Research Institute of Pulmonology of the I.P. Pavlov First St. Petersburg State Medical University,  St. Petersburg, Russian Federation, Kuzubova N.A. , Titova O.N. ,   Research Institute of Pulmonology of the I.P. Pavlov First St. Petersburg State Medical University,  St. Petersburg, Russian Federation, Volchkov V.A. ,   St. Petersburg State University, St. Petersburg, Russian Federation, Sklyarova D.B. ,   Research Institute of Pulmonology of the I.P. Pavlov First St. Petersburg State Medical University,  St. Petersburg, Russian Federation
Published: October 2020

Background: the progression of chronic obstructive pulmonary disease (COPD) is accompanied by pulmonary hypertension and right ventricular failure as well as left ventricular failure that can be associated with the elevated levels of N-terminal pro b-type natriuretic peptide (NT-proBNP). Aim: to evaluate the diagnostic importance of NT-proBNP in COPD with chronic hypoxemic respiratory failure. Patients and Methods: 60 patients with COPD GOLD stage 3 and 4 (group D, mixed phenotype: emphysematous bronchitic) during remission were examined. Mean age was 64.78±6.9 years. The patients were divided into three groups. Group 1 included 20 COPD patients with hypoxemia who received long-term oxygen therapy (LTOT). Group 2 included 20 COPD patients with hypoxemia who did not receive LTOT. Group 3 included 20 COPD patients with normoxemia. After the primary examination, group 1 patients were prescribed with in-home LTOT (16 hours daily). Group 2 and 3 patients were not prescribed with LTOT. All patients received basic treatment, i.e., a combined drug containing an inhaled corticosteroid and β2-agonist (budesonide/formoterol 400/12 μg twice daily) and a long-acting muscarinic antagonist (tiotropium bromide 2.5 μg, 2 inhalations once daily). The patients were reexamined after 12 months. Arterial blood gases and serum NT-proBNP concentration were measured, spirometry and Doppler echocardiography were performed. Results: NT-proBNP levels in COPD patients with hypoxemia were significantly elevated. The associations between NT-proBNP and partial oxygen arterial pressure (r= -0.71, p<0.05), NT-proBNP and pulmonary artery systolic pressure (PASP) (r=0.61, p<0.05) were revealed. ROC analysis of NT-proBNP demonstrated its sensitivity and specificity in COPD patients with the different severity of respiratory failure. LTOT for COPD with hypoxemia reduces PASP, improves left ventricular diastolic function, and decreases NT-proBNP levels. Conclusions: as chronic hypoxemic respiratory failure progresses in COPD, NT-proBNP concentration increases. ROC analysis demonstrates that NT-proBNP can be considered as a promising marker of hypoxemia and pulmonary hypertension. LTOT reduces NT-proBNP levels by improving pulmonary cardiac hemodynamics. KEYWORDS: COPD, hypoxemia, natriuretic peptide, long-term oxygen therapy, pulmonary hypertension, diastolic dysfunction, right ventricle. FOR CITATION: Kuzubova N.A., Titova O.N., Volchkov V.A., Sklyarova D.B. Diagnostic importance of natriuretic peptide in chronic obstructive pulmonary disease with chronic hypoxemic respiratory failure. Russian Medical Inquiry. 2020;4(4):174–179. DOI: 10.32364/2587-6821- 2020-4-4-174-179.