Aims: The prevalence, incidence, and prognostic value of anaemia in patients with an acute myocardial infarction (AMI) complicated by heart failure is unclear.
Methods and results: We analysed the relationship between haemoglobin (Hb) and outcome in 5010 patients with AMI complicated by heart failure in the OPTIMAAL study. In 3921 patients, follow-up Hb levels were available at 365 (+/-90) days. In a subgroup of 224 patients, iron-related haematinics were assessed at baseline and during follow-up. At baseline, mean Hb was 12.6 +/- 1.3 g/dL in women and 13.7 +/- 1.4 g/dL in men. Hb < 11.5 g/dL was found in 9.3% of patients (women: 18.2%, men: 5.8%). Lower haemoglobin at baseline was clearly associated with female gender and the presence of diabetes, higher age and Killip class, lower body mass index, systolic blood pressure, total cholesterol, and the absence of current smoking (all P < 0.05). Higher Hb [per one standard deviation (SD)] related to lower mortality [adjusted hazard ratios (HR) 0.88; 95% confidence interval (CI) 0.83-0.93], CHF hospitalizations [HR 0.85 (0.77-0.93)], and all-cause hospitalizations [HR 0.96 (0.92-0.99), all P < 0.05]. In patients without anaemia at baseline, the anaemia incidence after 1 year of follow-up was 10.1% in women and 10.0% in men. Of patients with anaemia at baseline, 65% did not have anaemia at 12 months and 46% did not have anaemia at any time during follow-up (median 3.0 years, inter-quartile range, Q1-Q3 = 2.7-3.3 years). At 12 months, an increase in Hb (per SD) was related to lower mortality [HR 0.73 (0.63-0.85; P < 0.0001)] independent of baseline Hb and other clinical characteristics.
Conclusion: In patients with complicated AMIs, anaemia on admission and/or reductions in haemoglobin during follow-up are independent risk factors for mortality and hospitalization. Studies are warranted to determine whether correcting anaemia after a complicated AMI improves outcome.