| |
|
|
|
|
|
|
|||
|
Blood, 1 March 2008, Vol. 111, No. 5, pp. 2941.
CORRESPONDENCE Defining anemia by race using epidemiologic dataTo the editor:We laud Patel and colleagues' thoughtful analysis and important contribution to the sparse literature on the racial variation in the relationship of anemia and outcome in older adults.1 The authors suggest that "alternative criteria are warranted" for defining anemia in blacks. They intimate that we should consider a threshold lower in blacks than the World Health Organization anemia criteria of hemoglobin (Hb) less than 130 g/L for men and less than 120 g/L for women based on their observation that anemia did not predict for increased mortality in blacks. However, we believe lowering the Hb threshold defining anemia based on this epidemiologic study is premature. Because the data conflict with Denny and colleagues' report showing increased mortality in older blacks having anemia, we must consider study limitations.2 In the manuscript by Dr Patel, the recruitment strategies for blacks and whites differed (whites were randomly selected whereas blacks were recruited) as did the number of patients lacking baseline Hb values (56% in blacks compared with 39% in whites). This may have introduced bias that abrogated the mortality impact of anemia. The authors also state that restricting the analysis to well-functioning individuals strengthens the study by negating confounding factors. However, to redefine population-based Hb thresholds in a nonpopulation-based analysis is problematic. Finally, it remains unknown whether anemia in older blacks increases the risk of other health-related outcomes such as hospitalization, quality of life, or institutionalization.
Even if anemia in older blacks is shown to have no impact on outcomes, defining anemia based solely on epidemiologic data may have unintended consequences. Anemia has long served as a clinically important sign of other conditions. Applying a lower Hb concentration to diagnose anemia would desensitize physicians and patients about when to evaluate anemia and/or may lead payors to refuse reimbursement for "mildly" low Hb values. As the authors point out, genetic traits, such as Authorship Conflict-of-interest disclosure: A.A. has served on an advisory board to Amgen and has received research support from Amgen. X.D. declares no competing financial interests. Correspondence: Andrew Artz, University of Chicago, 5841 S Maryland Avenue, MC 2115, Chicago, IL 60637; e-mail: aartz{at}medicine.bsd.uchicago.edu.
References
Related Article in Blood Online:
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Copyright © 2008 by American Society of Hematology Online ISSN: 1528-0020 | |||||||||