Association between Anemia and COPD in Iranian Population

BACKGROUND AND AIM Chronic obstructive pulmonary disease (COPD) is one of the major causes of morbidity and mortality in adults. Anemia is known as comorbidity in many chronic diseases that can increase morbidity and mortality of COPD. Recent studies have shown that anemia may be more prevalent than expected in COPD patients and can increase disabilities of COPD. In this study we have evaluated the correlation between anemia and the severity of COPD in patients referred to teaching hospitals of the Tehran University of Medical Sciences (TUMS), Tehran, Iran. MATERIALS AND METHODS In this cross-sectional study the severity of COPD in 760 patients with dyspnea who referred to teaching hospitals of Tehran University of Medical Sciences and 96 stable COPD patients were categorize using a GOLD criteria from mild to moderate, severe and very severe. Anemia was determined as hemoglobin <13 g/dL in men and <12 g/dL in women, respectively. Demographic characteristics, spirometry parameters and laboratory findings were compared between anemic and non-anemic groups using Student t-test and regression tests (SPSS v.18 software). RESULTS The Mean age of patients was 65 ± 13.07 years (59.4% male). Overall prevalence of anemia was 27% and there was no correlation between severity of COPD and anemia. Anemic patients were significantly older than non-anemic patients (71.1 ± 8.5 years vs. 65.4± 12.8 years; p = 0.030). RBC count of anemic patients were significantly lower than non-anemic group (4.3 ± 0.5 vs. 5.02± 0.8 ×106/µL; p < 0.001). Erythropoietin levels in anemic group was significantly higher than non-anemic group (16.33±2.43 vs. 10.22 ± 2.67 mu/ml; p < 0.001) and there was a significant inverse correlation of hemoglobin vs erythropoietin (r= -0.8). CONCLUSION There was a high prevalence of anemia in COPD patients. Anemia can increase disabilities of COPD. Thus, treatment of anemia may improve quality of life in these patients. Further comprehensive studies are needed for determination of exact prevalence of anemia and its physiologic effects in COPD.