Impact of anaemia and iron deficiency on outcomes in cardiogenic shock complicating acute myocardial infarction

Aims Anaemia and iron deficiency (ID) are common comorbidities in cardiovascular patients and are associated with a poor clinical status, as well as a worse outcome in patients with heart failure and acute myocardial infarction (AMI). Nevertheless, data concerning the impact of anaemia and ID on clinical outcomes in patients with cardiogenic shock (CS) are scarce. This study aimed to assess the impact of anaemia and ID on clinical outcomes in patients with CS complicating AMI.Methods and results The presence of anaemia (haemoglobin <13 g/dl in men and <12 g/dl in women) or ID (ferritin <100 ng/ml or transferrin saturation <20%) was determined in patients with CS due to AMI from the CULPRIT-SHOCK trial. Blood samples were collected in the catheterization laboratory during initial percutaneous coronary intervention. Clinical outcomes were compared in four groups of patients having neither anaemia nor ID, against patients with anaemia with or without ID and patients with ID only. A total of 427 CS patients were included in this analysis. Anaemia without ID was diagnosed in 93 (21.7%), anaemia with ID in 54 study participants (12.6%), ID without anaemia in 72 patients (16.8%), whereas in 208 patients neither anaemia nor ID was present (48.9%). CS patients with anaemia without ID were older (73 +/- 10 years, p = 0.001), had more frequently a history of arterial hypertension (72.8%, p = 0.01), diabetes mellitus (47.8%, p = 0.001), as well as chronic kidney disease (14.1%, p = 0.004) compared to CS patients in other groups. Anaemic CS patients without ID presence were at higher risk to develop a composite from all-cause death or renal replacement therapy at 30-day follow-up (odds ratio [OR] 3.83, 95% confidence interval [CI] 2.23-6.62, p < 0.001) than CS patients without anaemia/ID. The presence of ID in CS patients, with and without concomitant anaemia, did not increase the risk for the primary outcome (OR 1.17, 95% CI 0.64-2.13, p = 0.64; and OR 1.01, 95% CI 0.59-1.73, p = 0.54; respectively) within 30 days of follow-up. In time-to-event Kaplan-Meier analysis, anaemic CS patients without ID had a significantly higher hazard ratio (HR) for the primary outcome (HR 2.11, 95% CI 1.52-2.89, p < 0.001), as well as for death from any cause (HR 1.90, 95% CI 1.36-2.65, p < 0.001) and renal replacement therapy during 30-day follow-up (HR 2.99, 95% CI 1.69-5.31, p < 0.001).Conclusion Concomitant anaemia without ID presence in patients with CS at hospital presentation is associated with higher risk for death from any cause or renal replacement therapy and the individual components of this composite endpoint within 30 days after hospitalization. ID has no relevant impact on clinical outcomes in patients with CS.