Correspondence Response to Letter Regarding Article, “Endogenous Erythropoietin and Outcome in Heart Failure” We thank Dr Incalzi and coauthors for their thorough reading of our article. 1 They raise an important issue on chronic obstructive pulmonary disease (COPD)–related arterial hypoxemia and its influ- ence on erythropoietin production. We agree that besides the presence of heart failure (and its known comorbidities), other factors can influence the level of erythropoietin. However, in several clinical studies, no increase in erythropoietin was found in nonanemic patients with COPD compared with healthy control subjects. 2,3 In our heart failure study population, 28% (167 of 605) were diagnosed with COPD, which is consistent with data from other heart failure studies. 4 The presence of COPD did not influence erythropoietin levels in our study as assessed by univariable linear regression analysis (=0.026; P=0.53). To evaluate whether COPD influenced mortality of all causes in this heart failure cohort, we adjusted our multivariable Cox regression model for the presence of COPD. The addition of COPD did not strengthen our model, and more important, COPD was not an independent predictor of prog- nosis (hazard ratio, 1.18; 95% confidence interval, 0.90 to 1.56; P=0.24). Finally, the presence of COPD in patients with higher- than-expected erythropoietin levels based on their hemoglobin value was not significantly higher compared with patients with low or normal levels of erythropoietin. From these results, we conclude that the presence of COPD had no significant influence on the data that we presented. Disclosures Dr Voors has received unrestricted research grants from Amgen and Ortho Biotech. Dr van Veldhuisen has received lecture fees from Amgen and is a member of the Executive Committee of the Darbepoetin Morbidity/Mortality Heart Failure Trial (RED-HF). The other authors report no conflicts. Anne M.S. Belonje, MD Adriaan A. Voors, MD, PhD Peter van der Meer, MD, PhD Tiny Jaarsma, PhD Dirk J. van Veldhuisen, MD, PhD Department of Cardiology University Medical Center Groningen Groningen, the Netherlands Wiek H. van Gilst, PhD Department of Experimental Cardiology University Medical Center Groningen Groningen, the Netherlands References 1. Belonje AM, Voors AA, van der Meer P, van Gilst WH, Jaarsma T, van Veldhuisen DJ. Endogenous erythropoietin and outcome in heart failure. Circulation. 2010;121:245–251. 2. John M, Hoernig S, Doehner W, Okonko DD, Witt C, Anker SD. Anemia and inflammation in COPD. Chest. 2005;127:825– 829. 3. Sala E, Balaguer C, Villena C, Rios A, Noguera A, Nunez B, Agusti A. Low erythropoietin plasma levels during exacerbations of COPD. Respiration. 2010;80:190 –197. 4. Hawkins NM, Petrie MC, Jhund PS, Chalmers GW, Dunn FG, McMurray JJ. Heart failure and chronic obstructive pulmonary disease: diagnostic pitfalls and epidemiology. Eur J Heart Fail. 2009;11:130 –139. (Circulation. 2010;122:e450.) © 2010 American Heart Association, Inc. Circulation is available at http://circ.ahajournals.org DOI: 10.1161/CIRCULATIONAHA.110.960831 e450 by guest on June 25, 2017 http://circ.ahajournals.org/ Downloaded from