The influence of anemia on one-year exacerbation rate of patients with COPD-PH

BACKGROUND: Anemia is prevalent not only in COPD but also in pulmonary hypertension. We postulated that anemia may have certain prognostic value in COPD concomitant with PH due to COPD (COPD-PH). METHODS: We performed a 12-month prospective investigation to follow up COPD patients with or without PH assessed by right heart catheterization. Eligible patients were enrolled, stratified into COPD-PH-anemia group (n = 40), COPD-PH group (n = 42), COPD-anemia group (n = 48), and COPD group(n = 50), and then followed up for 12 months. RESULTS: After the follow-up, for both of the actual variation value and variation rate, the increase of NT-pro BNP (P<0.001; P = 0.03) and CAT score (P = 0.001; 0.002), as well as the decrease of PaO(2) (P = 0.03; 0.086) and Peak VO(2) (P = 0.021; 0.009) in COPD-PH-anemia group were highest among four groups. The cumulative one-year survival rates were similar among four groups (P = 0.434). The cumulative exacerbation-free rate was lowest in COPD-PH-anemia group among four groups (P<0.001). Hemoglobin was an independent promoting factor for the probability of hospitalization due to exacerbation ≧ 1/year in patients with COPD-PH-anemia [HR 3.121(2.325–5.981); P<0.001]. CONCLUSIONS: Anemia is a promoting factor for the worsening of exercise capacity, deterioration of hypoxemia, declining of life quality, and aggravation of exacerbations in patients with COPD-PH-anemia, by contrast with COPD-PH, COPD-anemia, and COPD.