CRP and pulmonary arterial hypertension: Previous studies used clinical factors (age, gender, smoking status, finger clubbing, dyspnea, 6-minute walking distance, and hospitalization), pulmonary function tests (PFTs), change in PFT, high-resolution computed tomography (HRCT) findings or scores, pulmonary hypertension, molecular biomarkers (metalloproteinase-7 and C-reactive protein [CRP]), and pathologic finding as variables in predictive models5–11.