Vlahakos Vassilios, Marathias Katerina, Lionaki Sofia, Loukides Stelios, Zakynthinos Spyros, Vlahakos Demetrios
1st Department of Intensive Care Medicine, National and Kapodistrian University of Athens, School of Medicine, Evangelismos General Hospital, Athens, Greece.
Department of Intensive Care Unit, Onassis Cardiac Surgery Center, Athens, Greece.
Expert Rev Respir Med. 2022 Apr;16(4):391-398. doi: 10.1080/17476348.2022.2045958. Epub 2022 Mar 1.
Although polycythemia has been considered a common adverse event in COPD, anemia is reported more often and has gained more importance than polycythemia over the last thirty years.
Factors considered to be associated with the development of anemia in COPD have included: Aging and kidney dysfunction with erythropoietin deficiency and bone marrow suppression due to uremic toxins; heart failure (HF), often encountered in COPD and accompanied by anemia in one-third of the cases; Low-grade chronic inflammation, directly suppressing bone marrow and diminishing iron absorption and utilization via increased hepcidin levels; long-term oxygen therapy (LTOT), ameliorating chronic hypoxia, and most important, RAS inhibitors, which are widely used for the comorbidities associated with COPD (hypertension, HF, CKD, diabetes) and have previously been shown to lower hematocrit values or cause anemia in various clinical conditions.
Introduction of LTOT in COPD and especially the established use of RAS inhibitors form the basis for the shift from polycythemia to anemia in COPD. Interestingly, when the SGLT2 inhibitors are introduced for cardiorenal protection in COPD, one could anticipate correction of anemia or even reemergence of polycythemia, since this new class of drugs can augment erythropoietin secretion and increase hematocrit values.
尽管红细胞增多症一直被认为是慢性阻塞性肺疾病（COPD）中常见的不良事件，但在过去三十年中，贫血的报道更为频繁，且比红细胞增多症更为重要。
被认为与COPD患者贫血发生相关的因素包括：衰老和肾功能不全导致促红细胞生成素缺乏以及尿毒症毒素引起的骨髓抑制；心力衰竭（HF），在COPD中经常出现，三分之一的病例伴有贫血；低度慢性炎症，直接抑制骨髓并通过增加铁调素水平减少铁的吸收和利用；长期氧疗（LTOT），改善慢性缺氧，以及最重要的是RAS抑制剂，其广泛用于与COPD相关的合并症（高血压、HF、慢性肾脏病、糖尿病），并且先前已显示在各种临床情况下会降低血细胞比容值或导致贫血。
COPD中LTOT的引入，尤其是RAS抑制剂的既定使用，构成了COPD从红细胞增多症向贫血转变的基础。有趣的是，当引入SGLT2抑制剂用于COPD的心脏肾脏保护时，可以预期贫血会得到纠正，甚至红细胞增多症会再次出现，因为这类新药可以增加促红细胞生成素的分泌并提高血细胞比容值。
