BACKGROUND Iron deficiency is frequent in patients undergoing cardiac surgery. The relevance of iron deficiency, however, is ill defined. Therefore, our study aimed to investigate the impact of iron deficiency (ferritin <100 μg L-1) with or without concomitant anaemia on clinical outcome after cardiac surgery. METHODS In this prospective observational study, 730 patients undergoing elective cardiac surgery were assigned into four groups according to their iron status and anaemia. Mortality, serious adverse events (SAEs), major cardiac and cerebrovascular events (MACCEs), allogenic blood transfusion requirements, and length of hospital stay were assessed during a 90-day follow-up period. The effect of iron deficiency on these outcomes was first calculated in models adjusting for anaemia only, followed by two multivariate models adjusting for anaemia and either the EuroSCORE II or any possible confounders. RESULTS The presence of iron deficiency (ferritin <100 μg L-1) was associated with an increase in 90-day mortality from 2% to 5% in patients without anaemia, and from 4% to 14% in patients with anaemia. Logistic regression resulted in an odds ratio of 3.5 (95% confidence interval: 1.5-8.4); P=0.004. The effect persisted in both multivariate models. Moreover, iron deficiency was associated with an increased incidence of SAEs, MACCEs, transfusion, and prolonged hospital stay. CONCLUSIONS Preoperative iron deficiency (ferritin <100 μg L-1) was independently associated with increased mortality, more SAEs, and prolonged hospital stay after cardiac surgery. These findings underline the importance of preoperative iron deficiency screening in the context of a comprehensive patient blood management programme, and highlight its importance as a research topic in cardiac surgery. CLINICAL TRIAL REGISTRATION NCT02031289.

中文翻译：

---

一项前瞻性研究表明，缺铁与接受心脏手术的患者死亡率较高有关。

背景技术在进行心脏手术的患者中经常缺铁。然而，铁缺乏症的相关性定义不清。因此，我们的研究旨在调查缺铁或缺铁（铁蛋白<100μgL-1）伴或不伴贫血对心脏手术后临床结局的影响。方法在这项前瞻性观察性研究中，根据铁状态和贫血将730例接受心脏择期手术的患者分为四组。在90天的随访期内评估了死亡率，严重不良事件（SAE），主要心脏和脑血管事件（MACCE），异体输血需求以及住院时间。铁缺乏对这些结果的影响首先是在仅针对贫血进行调整的模型中计算的，其次是两个针对贫血症进行调整的多元模型，以及EuroSCORE II或任何可能的混杂因素。结果缺铁（铁蛋白<100μgL-1）的存在与无贫血患者90天死亡率从2％增加到5％以及贫血患者从4％增加到14％有关。Logistic回归的比值比为3.5（95％置信区间：1.5-8.4）；P = 0.004。该效果在两个多元模型中均持续存在。此外，铁缺乏症与SAE，MACCE，输血和住院时间延长的发生率相关。结论术前铁缺乏（铁蛋白<100μgL-1）与死亡率增加，SAE增多和心脏手术后住院时间延长独立相关。这些发现强调了在全面的患者血液管理计划的背景下进行术前铁缺乏症筛查的重要性，并强调了其作为心脏外科手术研究主题的重要性。临床试验注册NCT02031289。