Elevated C-reactive protein levels are a sign of pulmonary arterial hypertension in AECOPD

Background: In chronic obstructive pulmonary disease (COPD) patients, the serum levels of C-reactive protein (CRP) are elevated and an increase of CRP is more exaggerated in the acute exacerbation form of COPD (AECOPD) than in stable COPD. Pulmonary arterial hypertension is a common complication of COPD. An increased level of CRP is known to be associated with the risk of systemic cardio-vascular disorders. However, few findings are available on the potential role of CRP in pulmonary arterial hypertension due to COPD. Methods: This study was performed prospectively and the study population was composed of 72 patients that were hospitalized due to AECOPD. After receiving acute management for AECOPD, serum CRP levels were evaluated, arterial oxygen pressure (PaO ₂), was measured, and the existence of pulmonary arterial hypertension under room air inhalation was determined in the patients. Results: The number of patients with pulmonary arterial hypertension was 47 (65.3%)., There was an increased prevalence of pulmonary arterial hypertension and an increase of serum CRP levels in patients with the higher stages of COPD (e.g., patients with stage 3 and stage 4 disease; P<0.05). The mean serum CRP levels of patients with pulmonary arterial hypertension and without pulmonary arterial hypertension were 37.6±7.4 mg/L and 19.9±6.6 mg/L, respectively (P<0.05). However, there was no significant difference of the mean values of PaO₂ between patients with pulmonary arterial hypertension and without pulmonary arterial hypertension statistically (77.8±3.6 mmHg versus 87.2±6.0 mmHg). Conclusion: We conclude that higher serum levels of CRP can be a sign for pulmonary arterial hypertension in AECOPD patients.